text:
General Authors Guidelines (PDF)
Home All issues Volume 1 (2014) Manufacturing Rev., 1 (2014) 9 Full HTML
Manufacturing Rev.
https://doi.org/10.1051/mfreview/2014007
2. Lightweight materials
3. Particular forming methods
4. Fundamental research ...
Manufacturing Rev. 2014, 1, 9
A critical review on special forming processes and associated research for lightweight components based on sheet and tube materials
Lang Lihui, Liu Kangning*, Gaoshen Cai, Xiying Yang, Chan Guo and Guoliang Bu
School of Mechanical Engineering and Automation, Beihang University, Beijing 100191, China
* e-mail: lkn_buaa@163.com
Received: 4 May 2014
Accepted: 1 July 2014
Lightweight materials, such as ultra-high strength steel, titanium alloys and aluminum alloys, are used widely in aerospace and automobile industries leading to increasing demands for advanced forming technologies. Recently many innovative sheet- and tube-forming methods have been proposed by researchers and R&D facilities around the word. These methods can greatly improve the formability of materials with low plasticity and can produce complex-shaped parts with good surface qualities. This review aims at providing an insight into the latest developments of particular sheet- or tubular-metal forming process and shows basic applications in modern industry.
Key words: Review / Lightweight material / Sheet forming / Tube forming
© L. Lihui et al., Published by EDP Sciences, 2014
A current widespread trend is to use lightweight materials with the advantage of producing lightweight components to achieve the goal of reduction of emissions and energy. However, the poor formability of advanced lightweight materials at room temperature has seriously hampered their wider application. Lightweight materials, such as ultra-high-strength steel [1], titanium alloys [2, 3] and aluminum alloys [4] are used extensively in aerospace and automobile industries leading to increasing demands for advanced forming technologies, as conventional forming methods lack the ability to meet the need for fabricating lightweight structures. In the 21st century, in metal forming area, many researchers and business R&D facilities have proposed many advanced innovative forming methods dealing with this problem. These particular forming methods have both strengths and weaknesses in their suitability for different types of sheet metal forming processes.
This paper first categories three kinds of lightweight materials and then gives a detailed introduction to some of the particular sheet forming methods, including hydroforming, viscous pressure forming, solid granular-medium forming, superplastic forming, impact hydroforming and asymmetric incremental sheet forming. The state-of-the-art and current applications of these processes are also discussed in addition to some current developments on the forming mechanisms.
2.1. Aluminum alloys
Aluminum alloys are effective materials for the reduction of vehicle weight and are expanding their applications over years (see Figure 1). Naka et al. [6, 7] investigated the effects of forming speed and temperature on the experimental forming limit diagram (FLD) for a fine grain Al-Mg alloy sheet by performing stretch-forming tests at various forming speeds at several temperatures. Li et al. [8, 9] investigated the uniaxial tensile deformation behavior of three aluminum sheet alloys including Al 5182, Al 5754 and Al 6111-T4 in the warm-forming temperature range using the torsion test method, Cavaliere [10] studied the hot and warm formability of 2618 aluminum alloy, precipitation being found during deformation.
Average use of aluminum [5].
2.2. Titanium alloys
Titanium alloys possess the beneficial properties of high specific strength and excellent corrosion resistance. Therefore, titanium alloys are found in aerospace applications where the combination of weight, strength, corrosion resistance and high temperature stability is highly valued [11].
Figure 2 shows the percentage of structural weight for various material classes in modern large commercial aircraft, distinguished between airframe and engine materials. The fuselage of the Airbus A330/340, for example, is manufactured of nearly two thirds aluminum. At about 7%, titanium alloys have a similar share of the structural weight to that of steels. However, at over a third of the structural weight, titanium is the second most common material in the jet engine, following Ni-based superalloys; and by volume, titanium alloys are the most abundant material in the engine [12].
Percentage of aluminum, titanium, and steel alloys and carbon fiber reinforce plastic (CFRP) of the structural weight of modern large commercial aircraft and gas turbine engines [12].
2.3. High-strength steels
In order to reduce vehicle weight and improve security, the increasing use of ultra-high-strength steels such as 22MnB5, 27MnCrB5, and 37MnB4 in the automotive industry has become an inevitable trend [13], Within this trend, advanced high-strength steel (AHSS) alloys have seen particularly fast growth [14], being used mainly in chassis components, such as the A-pillar, B-pillar, bumper, roof rail, rocker rail and tunnel (see Figure 3). Such prominent AHSS materials include dual phase, martensitic and boron steels [15]. Individual vehicle models and some companies have incorporated these advanced steels much more quickly than the fleet average: the Mercedes C-class jumped from 38% to 74% HSS in its body redesign, and the BMW X6 has 32% of its body and closure structures composed of AHSS [16]. Estimates from Ducker Worldwide indicate that the automobile industry will see an annual increase in AHSS of about 10% through to 2020 [17].
High strength steel used in a typical middle class car [13].
3.1. Hydroforming process (HF)
Hydroforming is a well-known long established process which was employed first to form sheets by the use of fluid medium as a soft punch before World War II. In recent years, with the reduction of cycle time and improvement of process controls, the fields of application of hydroforming have become broader. Hydroforming technology has gained increased interest in the world because of its many advantages.
Basically, the hydroforming process can be classified into two categories, sheet hydroforming and tube hydroforming [18], according to the different process features and the usage of different original blanks.
As shown in Figure 4a, a typical method in sheet hydroforming is hydraulic deep drawing (HDD). When the punch pushes the sheet metal into the die cavity, where oil or other liquids are contained, the established high pressure can press the sheet metal tightly onto the punch and a complex part will be formed. Another method is conventional sheet hydroforming (see Figure 4b), where, on the contrary, a rigid punch is replaced by pressurized liquids and the blank is bulged against a die.
Sheet hydroforming process [19]. (a) hydraulic deep drawing, (b) conventional sheet hydroforming.
Sheet hydroforming attracted widespread attention in the automobile industry when it was first applied to automotive parts as it provides products with relatively good surface quality compared with that of traditional deep drawing. Figure 5 [18] shows some automobile panels fabricated by the sheet hydroforming (SHF) process.
Application of sheet hydroforming (SHF) [18]. (a) Alfa Romeo hood, (b) Maybach roof.
Recently, the enthusiasm generated by HDD technology has cooled down, mainly due to the reasons discussed below [18], miscalculations on these two aspects keeping the SHF process away from series production:
The cycle time of the SHF process is too long compared to that of conventional deep drawing or stretch drawing, restricting the SHF process to niche applications.
Special controlling parameters are needed in the process and these parameters have to be acquired by car manufacturers before application in commercialized production. However, the optimized data is not easy to obtain, this being the key point in making full use of the technique.
Figure 6 presents a schematic diagram of a typical tube hydroforming process. A seamless tube or a welded tube is used to form the shape of the die cavity by internal pressure with the corresponding movements of the side punches.
Typical THF process [20].
Tube hydroforming has many advantages [21, 22] such as part consolidation, weight reduction, improved part strength. The process was first used in the automobile field for non-structural components, such as exhaust and intake systems or cooling pipes (see Figure 7), since hydroforming is able to fabricate very complex part in a single operation, therefore reducing assembly cost and weight. Applying this process to structural components is a big challenge, but due to the R&D investment of the automobile industry, many parts, such as suspension frames, A-pillars and engine cradles, have been successfully developed (see Figures 8 and 9) which not only have the characteristic of being of light weight but also maintain the same structural performance.
Exhaust parts produced by hydroforming (Schuler Hydroforming, Germany) [23].
Engine cradle [23].
An aluminum lower rail for the Volvo car (AP&T, Sweden) [23].
Among these, one of the first research programs on this application was carried out in the early 2000 s as an EU-funded project and successfully produced the prototype of an A-pillar reinforcement realized by bending and hydroforming a conical tube (see Figure 10).
Comparison between a conventional A-pillar (left) and a hydroformed A-pillar (right) [18].
In addition to the automotive industry, hydroforming has also gained growing interest in the aerospace industry in the production of some complicated structural parts. The group led by Wang and Yuan in HIT (Harbin Institute of Technology) [23] has done many relevant researches on the application of hydroforming aircraft parts (see Figure 11), and many parts have been formed out of aluminum alloys or welded stainless tube blanks.
Hydroformed parts used in the aerospace industry (HIT, China) [23].
Another new trend is to combine warm forming with sheet/tube hydroforming: the resultant process is called warm hydroforming, and can improve the formability of materials significantly. The tooling for conventional sheet metal forming at elevated temperature has been studied and developed for many years, all of which tooling is almost the same as that shown in Figure 12 [24].
Deep drawing tool at elevated temperature [24]. (a)
Using 1050, 5754 and 6016 series aluminum sheets, Bolt et al. [25] investigated the formability at elevated temperatures of from 100 to 250 °C. Both box and conical rectangular products were made with a tool with a heated die and blank holder. It was shown that forming at elevated temperature can yield a significant increase in product height, especially for conical products. The minimum die temperature for a significant effect on the process limit is lower for the Al6016 alloy than for the Al5751 alloy. The hardness of the warm-formed products does not differ significantly from that of products shaped at room temperature. Figure 13 shows the deepest-formed conical boxes using Al5754 and Al6016.
Formed aluminum boxes [25]. (a) Using 5754-O at room temperature (left) and 250 °C (right). (b) Using 6016-T4 at room temperature (left) and 175 °C (right).
Kleiner et al. [24] conducted bulging tests of tube hydroforming at elevated temperatures. The tube material was an Al alloy (AlMg3.5Mn) and was welded and annealed before the tests in order to secure good formability. Figure 14 shows the pressure curve versus the injected volume for warm tube hydroforming at room and elevated temperature. At room temperature, the pressure increased very quickly and failure of the tube occurred very soon in the process. By increasing the tool temperature to 275 °C and the temperature of the pressurized medium within the tube to 225 °C, the formability of the tube increased significantly.
tube warm hydroforming test at room temperature and 220 °C [24].
3.2. Viscous pressure forming (VPF)
The VPF process was invented in 1992 in the form of a patent and it is differed from conventional deep-drawing processes by applying viscous materials as the force-transmitting medium. Specifically, in the VPF process, high pressure exerted by viscous medium is applied on one side of a sheet metal blank to replace rigid punches, whilst back-pressure is also exerted to improve formabilities (see Figure 15). The viscous-medium forming method can make complex-shaped components with good surface quality and high dimensional accuracy, and at the same time reduce leakage [27]. Furthermore, the VPF process also has the advantage of producing parts made of high strength and in other light metals which are difficult to form by conventional sheet metal forming methods [28, 29].
A schematic diagram of VPF [26]: (1) medium injection cylinder;(2) upper die; (3) blank sheet; (4) viscous medium; (5) die; (6) medium outlet cylinder; (7) blank holder cylinder.
Ahmetoglu et al. [30] conducted VPF experiments on a non-symmetrical part at the ERC/NSM laboratory using three different materials, namely AKDQ steel, aluminum alloy 6111-T4 and Inco 718 SPF and studied the influence of process parameters, such as clamping load, forming speed and sheet metal blank material, on the technique (see Figure 16). Shulkin et al. [31] introduced an eight-point BHF control system to an experimental VPF machine and studied the formability by both simulation and experiment. Contrast experiments of bulging tests with three kinds of pressure-carrying media, viscous medium, polyurethane and steel, was studied by Wang et al. [32], the results showing that specimens formed with VPF have less wall-thinning and consequently have a more uniform wall thickness distribution compared with those formed with polyurethane and steel (see Figure 17).
SPF parts formed in VPF tooling [30]. (a) AKDQ steel, (b) Aluminum alloy 6111-T4, (c) Inco 718.
Parts obtained in the bulging experiment [32]. (a) Viscous medium bulging part, (b) polyurethane bulging part, (c) steel bulging part.
Liu et al. [33] improved VPF technology by using the process at elevated temperature to form an aluminum alloy sheet metal (see Figure 18). The limiting dome height (LDH) of test specimens was measured to evaluate the formability of VPF at different temperatures. Results showed that the LDH of bulging specimen at 200 °C attained 17.4 mm, 10.3% higher than that at room temperature. The influence of forming temperature on thickness distribution, forming load and failure location of sheet metal was also investigated. To the present day, the VPF process has basically remained in the research stage and has not been used extensively in the aerospace or automotive industries.
VPF specimens at elevated temperature [33].
3.3. Solid granular medium forming (SGMF)
The innovative technology of Solid Granular Medium Forming (SGMF) was proposed to overcome the disadvantages of leakage problems and poor heat resistibility of hydroforming by Zhao et al. [34–36]. In this process, a granular medium replaces water or oil or viscous materials as the force-transmitting medium. Considering that fluids normally used at room temperature are only temperature stable up to about 350 °C, using solid granular medium allow high temperatures and can totally reduce the risk of leakage. Similarly to the hydroforming method, this technology can fabricate both tubular parts (see Figure 19) and sheet parts (see Figure 20). Moreover, the non-uniform distribution of the internal pressure of solid granules can significantly improve the formability of the process, in addition, the interaction between the solid granular medium and the sheet metal surface can also greatly reduce the thinning of the workpiece [35].
Photo of deformed typical parts [34].
Schematic diagram of deep drawing and experimental equipment of AZ31B magnesium alloy [36]: (a) Diagram of deep drawing, (b) experimental equipment of deep drawing.
By conducting SGMF tests at warm temperatures, Cao et al. studied the granular medium forming performance of magnesium alloy sheet (see Figure 21) and determined that AZ31B magnesium alloy sheet achieves the best deep drawing performance under the conditions of a forming temperature of from 250 °C to 300 °C. These authors also found that the granular medium can apply axial friction on the cylinder wall to further improve the forming performance of metal sheet [36].
Deep drawing workpiece and contours band of thickness [36].
Merklein et al. [37, 38] used ceramic beads as a forming medium and designed and assembled an experimental apparatus (see Figure 22) to conduct the process at elevated temperatures. The apparatus can make SGMF parts at temperatures of up to 600 °C, when the lightweight materials such as high- and ultra-high-strength steel or titanium are suitable for forming.
Experimental tool for hydroforming using granular material as a medium at elevated temperatures [37].
3.4. Superplastic forming (SPF/DB)
Superplasticity is a characteristic of some fine-grained (3–5 μm) alloys when specimens under low stress conditions can exhibit neck-free elongations of very large values [39, 40]. Since the first superplastic part was made pneumatically from a sheet of superplastic Al-Zn eutectoid alloy 50 years ago [41] (see in Figure 23), this technology has been actively pursued in academic, research organizations and industrial R&D facilities around the world due to its special advantages of meeting some unique requirements in the aerospace and automobile industry.
The first superplastically formed bubble [41].
A schematic diagram of the SPF process can be seen in Figure 24, where a thin piece of sheet is put into the tools on a press and sealed at the edges, then the chamber is filled with high pressure gas at elevated temperature. The sheet is gradually deformed in a like manner to the blowing of bubble gum. The commercially available alloys for the SPF process are usually non-ferrous metals such as: aluminum alloy, titanium alloy and magnesium alloy [43].
Schematic of SPF process [42].
In general, the SPF process can produce parts with complex geometry and thus replace multi-piece assemblies with one monolithic component, without the need for welding or riveting parts together. Moreover, the components made by the SPF process can contain very little residual stress and have no spring-back [44]. The technology for SPF with aluminum alloys has progressed significantly in recent years. More often a non-planar clamp line tooling arrangement comprising an upper and a lower tool is used to replace planar tools to manufacture complex parts with curving edges (see Figure 25).
Non-planar clamp line SPF forming [43].
Perhaps aircraft manufacturing companies may have the most interest in this technique. The first SPF aluminum component fabricated by Boeing for civil aircraft was in 1992 [45], shown in Figure 26. Up to now, the emphasis at Boeing has focused on developing applications for the 5083 alloy because of its non-heat-treatable property, and many parts such as the 737 wing-tip light housing, the 767 moisture shroud, etc. [44] are manufactured in the SPF process, to save both cost and weight. SPF technology is often used along with diffusion bonding (SPF/DB) to further enhance the forming ability. After applying the SPF/DB process in building the F-15E fighter, it is estimated that about 726 parts and 10,000 fasteners are eliminated (Figure 27). The SPF process also made the wide-chord hollow fan blade possible in aero-engines (see Figure 28).
737 blowout door [45].
The use of superplastic forming-diffusion bonding to reduce the fuselage part count in F-15E aft fuselage (blats SPF-DB) showing (a-left) before and (b-right) after SPF-DF [46].
The titanium fan blade for Trent 900 engine.
The promotion of the SPF process is limited in the automobile industry and only niche markets, including specialist vehicles and limited-series sports cars, are suitable for SPF applications [47]. Figure 29 shows the 2006 limited-series reproduction of the 1954 classic Jaguar C-Type in which the SPF process is applied [43]. The reasons why the SPF process is not suitable for Production cars are listed below:
The production rate is low and usually for low/medium volume applications.
Unique requirements for the materials, which are relatively expensive.
The advantage of forming complex part is not highly valued in high-volume models.
The 2006 limited series reproduction of the 1954 classic Jaguar C-Type [43].
Today the materials used for the SPF process are not limited to metal alloys. Non-metal materials, such as superplastic ceramics [47] (see Figure 30) and glassy metals [49], also demonstrate their ability in the SPF process.
First bubbles superplastically formed from ceramic sheet.
3.5. Impact hydroforming method (IHF)
The innovative method of impact hydroforming (IHF) was proposed by Lang et al. [50] to meet the requirements of forming complex parts with small features which are very common in the automotive and aircraft industries. In the process, most of the geometrical features are formed by hydroforming (see Figure 31b) and some small fillet radius features are rapidly reshaped by high intensity impact energy (see Figure 31c) in a very short time. They also designed an IHF test setup (see Figure 32) to conduct experiments into the process (see Figure 33).
Steps of impact hydroforming technology [50]. (a) Preparation before forming. (b) The hydroforming step. (c) The impact forming step.
The IHF equipment.
Formed part by IHF process.
The original idea of impulsive pressure forming can be traced back into the 1960s [50], thus the IPF process can be viewed as a developed method in combination with hydroforming. Moreover, compared with traditional hydroforming methods, impact hydroforming technology can greatly improve the forming speed and the forming accuracy of sheet-metal component. The loading is quite short – less than 10 ms – and strict sealing is not required for the equipment. Moreover, the uniformity of wall thickness of the components can also be assured, as liquid medium fills the whole die cavity and establishes well-distributed pressure [50].
3.6. Asymmetric incremental sheet forming (AISF)
The Asymmetric Incremental Sheet Forming (AISF) process was first described by Mason in 1978 [52] and was developed mainly for the needs of the low volume production of sheet-metal parts. In the AISF process, a metal sheet is placed in the tooling and clamped at the edges, then a tool moves following the required shape in space under CNC control by a succession of "planar" contours or a single "spiral" contour so that the part is obtained as the result of accumulated localized plastic deformations [53]. The AISF process (see Figure 34) is similar to the spinning process but, with the absence of workpiece rotation, asymmetric components can be manufactured by the independent controlling of the X, Y and Z axis movements. One significant advantage of this technology is the ability to form asymmetric shapes at low cost, without the need of expensive dies.
Process principle of AISF process [54].
Basically, two main variations of conventional AISF are distinguished: "single point incremental forming" (SPIF) and "two point incremental forming" (TPIF) [54]. Figure 35 shows the different configurations that are included in the group of ASIF techniques. In the SPIF process, the blank edge is clamped without any further support except for the forming tool (see Figure 35a) [55]; whilst Figure 35b presents a special AISF process with counter tools. Up to now, considerable achievements of this process have been made by Kim and Yang [56], Leach et al. [57], and Felici et al. [58]. In the TPIF process (also called the backward bulge method by Matsubara [59]), there may be a simple support or a partial or full die (see Figures 35c and 35d.) Both symmetric and asymmetric shapes can be fabricated using the TPIF or SPIF processes. The configuration shown in Figures 35c and 35d are usually associated with machines dedicated to the incremental forming process, and those in Figures 35a and 35b are usually modified in a CNC milling machine [60].
Four categories of AISF process [55]. (a) Single point incremental forming; (b) Incremental forming with counter tools; (c) Two point incremental forming (partial die); (d) Two point incremental forming (full die).
As mentioned above, the major advantage of asymmetric incremental forming is the property of making asymmetric parts quickly and economically, without using expensive dies. Shapes used to demonstrate the abilities of the process are shown in Figure 36 [60]. Now the AISF process has been used for designs that were made as Rapid Prototypes for the automotive industry [61] (see Figure 37) and the medical industry [62] (see Figure 38).
Shapes used to demonstrate the ability of the process and for experiments [60].
Rapid prototypes for automotive industries [61].
The manufacture of an ankle support [62].
4. Fundamental research for special sheet and tube forming
In addition to the specific methods of implementing these special sheet and tube forming processes, emphasis has also been paid on the fundamental research concerning those techniques, such as the deformation mechanism, forming limit study, macro-deformation and micro-structure evolution of the forming process. All the work was done in order to further enhance the formability and help to obtain the optimum processing parameters.
4.1. Mechanism of the HF process
It is widely believed that the main reason why the hydroforming process greatly improves the formability of the material is the introduction of through-thickness normal stress which causes superimposed hydrostatic pressure on the sheet metal.
Wu et al. [63] carried out a detailed analysis of uniaxial tension under superimposed hydrostatic pressure (see Figure 39) and demonstrated that the superimposed hydrostatic pressure lowers the true stress level at yielding by the amount of the superimposed hydrostatic pressure without affecting work-hardening; the increase of sheet metal limit strains for any strain path under superimposed hydrostatic pressure has also been observed.
Schematic representation of a tensile sample in a pressure vessel [63].
Fuchs [64] found that the forming limit of tube can be improved remarkably by applying liquid pressure to the inside and outside of the tube simultaneously. Cui et al. [65] designed a special experimental setup (see Figure 40) for double-sided tube hydroforming; the result shows that increase of external pressure has an effect on the fraction of grain boundaries, and on the number and size of the microvoids in the transition zone, and thus increases the critical effective strain in the transition zone. Liu et al. [66] simulated the effect of through-thickness normal stress on the sheet formability using the finite element software based on the ductile fracture criterion.
Experimental setup of double-sided tube hydroforming process [65].
Assempour et al. [67] studied the effect of normal stress on the prediction of the forming limit diagrams (FLDs) based on the Marciniak and Kuczynski (M-K) model with some modifications on the stress states for consideration of the normal stress effects; as expected, the compressive normal stress shifts the FLD upwards (see Figure 41). Michel and Picart [68] conducted tensile and hydraulic bulging tests (see Figure 42) to investigate the size effects on the constitutive behaviour of brass in sheet metal forming; both experiments showed the same trends, in that the flow curve decreases with a decrease of thickness: a new model considering the size effect was established.
Effect of normal stress on shifting the FLDs for DP600 [67] (S is normalized normal stress).
Hydraulic bulging machine [68].
4.2. Mechanism of the SPF process
The deformation mechanism of fine-grain aluminum alloys is generally accepted as grain-boundary-sliding (GBS) creep, which supplies a high strain-rate sensitivity for successful commercial superplastic forming operations [69, 70]. Aluminum alloy 5083 is the most common material in SPF operations and many researches have been focused on it.
Kulas et al. [70] studied the plastic deformation of seven 5083 commercial aluminum materials and found two mechanisms governing plastic deformation in AA5083: grain-boundary-sliding (GBS) creep and solute-drag (SD) creep. Quantitative analysis of stress transients following different strain rates offers conclusive proof that SD creep dominates deformation at high strain rates and low temperature, whereas GBS creep occurs at high temperatures and low strain rates. Furthermore, deformation mechanism maps characterizing deformation in the fine-grained AA5083 materials were also constructed.
Kulas and Green [71] further investigated the failure mechanisms in AA5083 materials under uniaxial tension at elevated temperatures (see Figure 43) and discovered that the deformation dominated by grain-boundary-sliding creep leads to failure controlled by cavitation and the deformation dominated by solute-drag creep leads to failure controlled by flow localization. Further, the cavitation growth rate under SD creep is significantly less than that under GBS creep.
The failure regions of specimens are shown for (a) failure controlled by necking when deformation is by SD creep, (b) failure controlled by cavitation when deformation is by GBS creep [71].
Li et al. [72] studied the superplastic behavior and microstructure of rolled Mg-Gd-Y-Zr alloy sheet and established that the high ductility of Mg-Gd-Y-Zr alloy can be attributed to grain boundary sliding accommodated by dislocation motion assisted by lattice diffusion. Microstructural analysis indicated that the second phases exhibited the significant effect of pinning grain boundaries (see Figure 44).
TEM images of the fractured specimen tested at 435 °C and 0.0005 s−1. (a) An example of grain boundary and subgrain boundary, (b) a strip recrystallized grain, (c) dislocation network within the β phase [72].
4.3. Mechanism of the AISF process
The asymmetric single- and two-point incremental sheet forming processes are still in their infancy. Much research work remains to be done and to do this appropriate design of shapes (see Figure 36) need to be developed for the tests of FLDs, springback and roughness.
Jackson and Allwood [73] conducted special tests similar to those designed by Kalpakcioglu [74] using brazed plates in which a grid pattern was machined onto the cross-section of a half-plate (see Figure 45), which was then formed before being separated by heating. The deformation pattern of SPIF, TPIF and pressing was observed and it was revealed that the deformation mechanisms of both SPIF and TPIF are increasing stretching and shear in the radial-axial plane (perpendicular to the tool direction) and shear in the tool direction. Among these, shear in the tool direction, which is likely to be a result of friction between the tool and workpiece, is the most significant strain component. Silva et al. [75] studied the influence of process variables such as the tool radius to propose a new unified view on formability limits in the principal strain space and identified a critical threshold for the ratio between the thickness of the sheet and the radius of the tool that distinguishes between fracture with and without previous necking.
Schematic diagram of method for measuring through-thickness deformation by Jackson et al [73]. (a) Copper plate with gridded cross-section; (b) Plate with brazed joint; (c) Formed plate; (d) Separated plate with distorted grid pattern.
Young and Jeswiet [76] used more than one shape to develop a non-traditional FLD for 1.21 mm thick AA 3003-0 formed by the AISF process. The non-traditional FLD could provide the designer with an additional method of judging if a design can be made in one pass with AISF. (The boundary for safe forming is shown by the dashed line in Figure 46). Both Filice et al. [77] and Young [76] have found the same tendency of the boundary slope in the composite FLD.
Non-traditional FLD formed by AISF method of 1.21 mm thick AA 3003-0 [76].
Surface roughness is a major concern in a final product. In AISF the incremental step size, ∆z, is the major factor in determining surface roughness [78, 79] which is shown in Figure 47. Junk et al. [79] also studied the effect of pitch ∆z and tool radius upon surface roughness and found the interrelationship between these parameters in the AISF process.
illustration of how the pitch size, ∆z, influences roughness [60].
The springback effect is the main cause of the dimensional accuracy problems in the AISF process and has been widely investigated by several authors [80–83] Lasunon and Knight [80] developed a model to compare the accuracy of single-point incremental forming and double-point incremental forming and found the FE model was in good agreement with experimental data (see Figure 48). Several strategies have been proposed to overcome accuracy problems such as systems with flexible programmable back support structures [82] and systems with a localized heating device [83].
Comparison of profile plots gained from FEM and experimental results [80].
4.4. The issues to be addressed
A large amount of researches on these particular techniques has been undertaken to further enhance the formability of sheet and tube metal, although many problems still remains to be solved or improvements made to the aforementioned processes, among which some issues are listed below:
The accurate simulation of forming processes requires in-depth comprehension of the friction mechanism between the blank and the tool, considering the effects of lubrication. With the application of lubrication, formability of metal sheet is increased as a consequence of reduced friction and it is possible to get more homogeneous thickness distributions [84].
Some of the special forming methods are conducted under relatively high temperatures, which may affect the microscopic and mechanical properties of the deformed components, so thermal influence should also be identified.
The FLD under complex strain paths is very important in forming sheet or tubular components with complex geometries has not yet been investigated. Also the influences of temperature and viscoplastic effect on FLD have attracted great interests from researchers recently [85].
Further research targeting onto improved hardware, tool path generation and control strategy development would be helpful in securing industrial opportunities.
Lightweight materials such as ultra-high-strength steel, titanium alloys and aluminum alloys are used widely to help to achieve the goal of emissions- and energy-reduction. In this review, recent developments on some particular sheet forming methods and their forming mechanisms (HF, VPF, SGMF, SPF/DB, IHF and AISF) are critically summarized with the objective of evaluating the different research results and indicating the current applications in the aerospace and automotive industries.
In general, some of these techniques have been used extensively to fabricate hard-to-form and complex-shaped components, i.e. hydroforming and superplastic forming processes, on the occasions where conventional forming methods cannot fulfill the requirements of the manufacturers. Some other techniques remain at the stage of laboratory research and need to be refined before spreading into modern industries.
J. Aspacher, Forming hardening concepts, 1st International Conference on Hot Sheet Metal Forming of High Performance Steel, Kassel, Germany, 2008, pp. 77–81. [Google Scholar]
R.R. Boyer, Applications of beta titanium alloys in airframes, Beta Titanium Alloys in the I990's, Warrendale, PA, TMS, 1993, pp. 335–346. [Google Scholar]
M. Peters, J. Kumpfert, C.H. Ward, C. Leyens, Titanium alloys for aerospace applications, Advanced Engineering Materials 5, 6 (2003) 419–427. [CrossRef] [Google Scholar]
K. Martchek, Modelling more sustainable aluminium, The International Journal of Life Cycle Assessment 11, 1 (2006) 34–37. [CrossRef] [Google Scholar]
S. Toros, F. Ozturk, I. Kacar, Review of warm forming of aluminum-magnesium alloys, Journal of Materials Processing Technology 207, 1 (2008) 1–12. [CrossRef] [Google Scholar]
T. Naka, G. Torikai, R. Hino, F. Yoshida, The effects of temperature and forming speed on the forming limit diagram for type 5083 aluminum-magnesium alloy sheet, Journal of Materials Processing Technology 113, 1 (2001) 648–653. [CrossRef] [Google Scholar]
T. Naka, Y. Nakayama, T. Uemori, R. Hino, F. Yoshida, Effects of temperature on yield locus for 5083 aluminum alloy sheet, Journal of Materials Processing Technology 140, 1 (2003) 494–499. [CrossRef] [Google Scholar]
D. Li, A. Ghosh, Tensile deformation behavior of aluminum alloys at warm forming temperatures, Materials Science and Engineering: A 352, 1 (2003) 279–286. [CrossRef] [Google Scholar]
D. Li, A. Ghosh, Biaxial warm forming behavior of aluminum sheet alloys, Journal of Materials Processing Technology 145, 3 (2004) 281–293. [CrossRef] [MathSciNet] [Google Scholar]
P. Cavaliere, Hot and warm forming of 2618 aluminium alloy, Journal of Light Metals 2, 4 (2002) 247–252. [CrossRef] [Google Scholar]
R.R. Boyer, An overview on the use of titanium in the aerospace industry, Materials Science and Engineering: A 213, 1 (1996) 103–114. [CrossRef] [Google Scholar]
C. Leyens, M. Peters, Titanium and titanium alloys, Wiley-VCH, Weinheim, 2003. [CrossRef] [Google Scholar]
H. Karbasian, A.E. Tekkaya, A review on hot stamping, Journal of Materials Processing Technology 210, 15 (2010) 2103–2118. [CrossRef] [Google Scholar]
D. Keith, HSS, AHSS and aluminum jockey for position in the race to cut auto curb weight, American Metal Market Monthly (2010) 1. [Google Scholar]
R. Kuziak, R. Kawalla, S. Waengler, Advanced high strength steels for automotive industry, Archives of Civil and Mechanical Engineering 8, 2 (2008) 103–117. [CrossRef] [Google Scholar]
N.P. Lutsey, Review of technical literature and trends related to automobile mass-reduction technology, Institute of Transportation Studies, University of California, Davis, CA, 2010. [Google Scholar]
D. Anderson, New study finds increased use of advanced high-strength steels helps decrease overall vehicle weight, AISI News Release, Detroit, 2009. [Google Scholar]
M. Tolazzi, Hydroforming applications in automotive: a review, International Journal of Material Forming 3, 1 (2010) 307–310. [CrossRef] [Google Scholar]
M. Koç, Hydroforming for advanced manufacturing, Woodhead Publishing, UK, 2008. [Google Scholar]
M. Koç, A. Taylan, An overall review of the tube hydroforming (THF) technology, Journal of Materials Processing Technology 108, 3 (2001) 384–393. [CrossRef] [Google Scholar]
M. Ahmetoglu, K. Sutter, X.J. Li, T. Altan, Tube hydroforming: current research, applications and need for training, Journal of Materials Processing Technology 98, 2 (2000) 224–231. [CrossRef] [Google Scholar]
B. Constantine, R. Roth, J.P. Clark, Substituting tube-hydroformed parts for automotive stampings: an economic model, Journal of Modeling 53, 8 (2001) 33–38. [Google Scholar]
L.H. Lang, Z.R. Wang, D.C. Kang, S.J. Yuan, S.H. Zhang, J. Danckert, K.B. Nielsen, Hydroforming highlights: sheet hydroforming and tube hydroforming, Journal of Materials Processing Technology 151, 1 (2004) 165–177. [CrossRef] [Google Scholar]
M. Kleiner, M. Geiger, A. Klaus, Manufacturing of lightweight components by metal forming, CIRP Annals-Manufacturing Technology 52, 2 (2003) 521–542. [CrossRef] [Google Scholar]
P.J. Bolt, N.A.P.M. Lamboo, P.J.C.M. Rozier, Feasibility of warm drawing of aluminium products, Journal of Materials Processing Technology 115, 1 (2001) 118–121. [CrossRef] [Google Scholar]
L.J. Rhoades, M.L. Rhoades, Die forming metallic sheet materials, US Patent No. 5,085,068, 4 Feb. 1992. [Google Scholar]
Z.J. Wang, J.G. Liu, X.Y. Wang, Z.Y. Hu, B. Guo, Viscous pressure forming (VPF): state-of-the-art and future trends, Journal of Materials Processing Technology 151, 1 (2004) 80–87. [CrossRef] [Google Scholar]
Z.J. Wang, Z.R. Wang, H.F. Yang, Experimental investigation for viscous medium drawing of sheet metal under the condition of non-uniform blank holder force, Journal of Plasticity Engineering 6, 2 (1999) 50–52. [Google Scholar]
Z.R. Wang, X.Y. Wang, Z.J. Wang, Numerical simulation and experimental research on the forming of thin-walled complex parts with viscous pressure forming VPF, NUMISHEET, Korea, 2002, pp. 249–252. [Google Scholar]
M. Ahmetoglu, J. Hua, S. Kulukuru, T. Altan, Hydroforming of sheet metal using a viscous pressure medium, Journal of Materials Processing Technology 146, 1 (2004) 97–107. [CrossRef] [Google Scholar]
L.B. Shulkin, R.A. Posteraro, M.A. Ahmetoglu, G.L. Kinzel, T. Altan, Blank holder force (BHF) control in viscous pressure forming (VPF) of sheet metal, Journal of Materials Processing Technology 98, 1 (2000) 7–16. [CrossRef] [Google Scholar]
X.Y. Wang, J.C. Xia, G.A. Hu, Z.J. Wang, Z.R. Wang, Sheet bulging experiment with a viscous pressure-carrying medium, Journal of Materials Processing Technology 151, 1 (2004) 340–344. [CrossRef] [Google Scholar]
J. Liu, Q. Peng, Y. Liu, Z. Wang, Viscous pressure bulging of aluminum alloy sheet at warm temperatures, Journal of Mechanical Science and Technology 21, 10 (2007) 1505–1511. [CrossRef] [Google Scholar]
C.C. Zhao, G.J. Dong, H. Xiao, Y.S. Wang, New process of solid granule medium forming, Journal of Mechanical Engineering 8 (2009) 046. [Google Scholar]
G.J. Dong, C.C. Zhao, M.Y. Cao, Flexible-die forming process with solid granule medium on sheet metal, Transactions of Nonferrous Metals Society of China 23, 9 (2013) 2666–2677. [CrossRef] [Google Scholar]
M.Y. Cao, C.C. Zhao, G.J. Dong, Numerical simulation on granules medium drawing process parameters of magnesium alloy sheet, The Chinese Journal of Nonferrous Metals 22, 11 (2012) 2992–2999. [Google Scholar]
M. Grüner, M. Merklein, Numerical simulation of hydro forming at elevated temperatures with granular material used as medium compared to the real part geometry, International Journal of Material Forming 3, 1 (2010) 279–282. [CrossRef] [Google Scholar]
M. Grünerak, M. Merklein, Influences on the molding in hydroforming using granular material as a medium, AIP Conference Proceedings 1383 (2011) 645–652. [Google Scholar]
J. Bonet, A. Gil, R.D. Wood, R. Said, R.V. Curtis, Simulating superplastic forming, Computer Methods in Applied Mechanics and Engineering 195, 48 (2006) 6580–6603. [CrossRef] [MathSciNet] [Google Scholar]
G.J. Davies, J.W. Edington, C.P. Cutler, K.A. Padmanabhan, Superplasticity: a review, Journal of Materials Science 5, 12 (1970) 1091–1102. [CrossRef] [Google Scholar]
W.A. Backofen, I.R. Turner, D.H. Avery, Superplasticity in an Al-Zn alloy, Transactions of ASM 57, 4 (1964) 980–990. [Google Scholar]
A.J. Barnes, Superplastic forming 40 years and still growing, Journal of Materials Engineering and Performance 16, 4 (2007) 440–454. [CrossRef] [Google Scholar]
L.D. Hefti, Commercial airplane applications of superplastically formed AA5083 aluminum sheet, Journal of Materials Engineering and Performance 16, 2 (2007) 136–141. [CrossRef] [Google Scholar]
L.D. Hefti, Using superplastic forming as a means of achieving cost benefits as well as enhancing aircraft performance, High Performance Metallic Materials for Cost Sensitive Applications, John Wiley and Sons, Hoboken, NJ, 2002 pp. 64–72. [Google Scholar]
R. Martin, D. Evans, Reducing costs in aircraft: the metals affordability initiative consortium, Journal of Modeling 52, 3 (2000) 24–28. [Google Scholar]
A.J. Barnes, Superplastic aluminum forming-expanding its techno-economic niche, Materials Science Forum 304 (1999) 785–796. [CrossRef] [Google Scholar]
J. Wittenauer, T.G. Nieh, J. Wadsworth, A first report on superplastic gas-pressure forming of ceramic sheet, Scripta Metallurgica et Materialia 26, 4 (1992) 551–556. [CrossRef] [Google Scholar]
T. Waniuk, J. Schroers, W.L. Johnson, Timescales of crystallization and viscous flow of the bulk glass-forming Zr-Ti-Ni-Cu-Be alloys, Physical Review B 67, 18 (2003) 184203. [CrossRef] [Google Scholar]
L.H. Lang, S.H. Wang, C.L. Yang, Investigation on the innovative impact hydroforming technology, The 11th International Conference on Numerical Methods in Industrial Forming Processes: NUMIFORM 2013 1532, 1 (2013) 791–798. [Google Scholar]
H. Tominga, M. Takamatsu, Hydropunch, a pneumatic-hydraulic-forming machine, International Conference of the Center for High Energy Forming, Estes Park, USA, 1969. [Google Scholar]
B. Mason, Sheet metal forming for small batches, Bachelor thesis, University of Nottingham, May 1978. [Google Scholar]
W.C. Emmens, G. Sebastiani, A.H.V.D. Boogaard, The technology of incremental sheet forming – a brief review of the history, Journal of Materials Processing Technology 210, 8 (2010) 981–997. [CrossRef] [Google Scholar]
B.T. Araghi, A. Göttmann, M. Bambach, G. Hirt, G. Bergweiler, J. Diettrich, M. Steiners, A. Saeed-Akbari, Review on the development of a hybrid incremental sheet forming system for small batch sizes and individualized production, Production Engineering 5, 4 (2011) 393–404. [CrossRef] [Google Scholar]
M. Bambach, G. Hirt, S. Junk, Modelling and experimental evaluation of the incremental CNC sheet metal forming process, 7th International Conference on Computational Plasticity, Barcelona, Spain, 2003. [Google Scholar]
T.J. Kim, D.Y. Yang, Improvement of formability for the incremental sheet metal forming process, International Journal of Mechanical Sciences 42, 7 (2000) 1271–1286. [CrossRef] [Google Scholar]
D. Leach, A.J. Green, A.N. Bramley, A new incremental sheet forming process for small batch and prototype parts, 9th International Conference on Sheet Metal, Leuven, 2001. [Google Scholar]
L. Filice, L. Fratini, F. Micari, Analysis of material formability in incremental forming, CIRP Annals-Manufacturing Technology 51, 1 (2002) 199–202. [CrossRef] [Google Scholar]
S. Matsubara, Incremental backward bulge forming of a sheet metal with a hemispherical head tool-a study of a numerical control forming system II, Journal-Japan Society for Technology of Plasticity 35 (1994) 1311–1311. [Google Scholar]
J. Jeswiet, F. Micari, G. Hirt, A. Bramley, J. Duflou, J. Allwood, Asymmetric single point incremental forming of sheet metal, CIRP Annals-Manufacturing Technology 54, 2 (2005) 88–114. [CrossRef] [Google Scholar]
J. Jeswiet, E. Hagan, Rapid prototyping of a headlight with sheet metal, Canadian Institute of Mining, Metallurgy and Petroleum, Canada, 2001, pp. 109–114. [Google Scholar]
F. Micari, Single point incremental forming: recent results, Seminar on Incremental Forming, Cambridge University, Cambridge, 22 October, 2004. [Google Scholar]
P.D. Wu, J.D. Embury, D.J. Lloyd, Y. Huang, K.W. Neale, Effects of superimposed hydrostatic pressure on sheet metal formability, International Journal of Plasticity 25, 9 (2009) 1711–1725. [CrossRef] [Google Scholar]
F. Fuchs, Hydrostatic pressure – its role in metal forming, Mechanical Engineering 88, 4 (1966) 34–40. [Google Scholar]
X.L. Cui, X.S. Wang, S.J. Yuan, Deformation analysis of double-sided tube hydroforming in square-section die, Journal of Materials Processing Technology 214, 7 (2014) 1341–1351. [CrossRef] [Google Scholar]
J.G. Liu, Z.J. Wang, Q.Y. Meng, Numerical investigations on the influence of superimposed double-sided pressure on the formability of biaxially stretched AA6111-T4 sheet metal, Journal of Materials Engineering and Performance 21, 4 (2012) 429–436. [CrossRef] [Google Scholar]
A. Assempour, H.K. Nejadkhaki, R. Hashemi, Forming limit diagrams with the existence of through-thickness normal stress, Computational Materials Science 48, 3 (2010) 504–508. [CrossRef] [Google Scholar]
J.F. Michel, P. Picart, Size effects on the constitutive behaviour for brass in sheet metal forming, Journal of Materials Processing Technology 141, 3 (2003) 439–446. [CrossRef] [Google Scholar]
T.G. Nieh, J. Wadsworth, O.D. Sherby, Superplasticity in metals and ceramics, Cambridge University Press, Cambridge, 2005. [Google Scholar]
M.A. Kulas, W.P. Green, E.M. Taleff, P.E. Krajewski, T.R. McNelley, Deformation mechanisms in superplastic AA5083 materials, Metallurgical and Materials Transactions A 36, 5 (2005) 1249–1261. [CrossRef] [Google Scholar]
M.A. Kulas, W.P. Green, E.M. Taleff, P.E. Krajewski, T.R. McNelley, Failure mechanisms in superplastic AA5083 materials, Metallurgical and Materials Transactions A 37, 3 (2006) 645–655. [CrossRef] [Google Scholar]
L. Li, X. Zhang, Y. Deng, C. Tang, Superplasticity and microstructure in Mg-Gd-Y-Zr rolled sheet, Journal of Alloys and Compounds 485, 1 (2009) 295–299. [CrossRef] [Google Scholar]
K. Jackson, J. Allwood, The mechanics of incremental sheet forming, Journal of Materials Processing Technology 209, 3 (2009) 1158–1174. [CrossRef] [Google Scholar]
S. Kalpakcioglu, On the mechanics of shear spinning, Journal of Engineering for Industry 83, 2 (1961) 125–130. [CrossRef] [Google Scholar]
M.B. Silva, P.S. Nielsen, N. Bay, P.A.F. Martins, Failure mechanisms in single-point incremental forming of metals, The International Journal of Advanced Manufacturing Technology 56, 9–12 (2011) 893–903. [CrossRef] [Google Scholar]
J. Jeswiet, D. Young, Forming limit diagrams for single-point incremental forming of aluminium sheet, Proceedings of the Institution of Mechanical Engineers, Part B: Journal of Engineering Manufacture 219, 4 (2005) 359–364. [CrossRef] [Google Scholar]
E. Hagan, J. Jeswiet, Analysis of surface roughness for parts formed by computer numerical controlled incremental forming, Proceedings of the Institution of Mechanical Engineers, Part B: Journal of Engineering Manufacture 218, 10 (2004) 1307–1312. [CrossRef] [Google Scholar]
S. Junk, G. Hirt, I. Chouvalova, Forming strategies and tools in incremental sheet forming, Proceedings of the 10th International Conference on Sheet Metal, Belfast, 2003. [Google Scholar]
O. Lasunon, W.A. Knight, Comparative investigation of single-point and double-point incremental sheet metal forming processes, Proceedings of the Institution of Mechanical Engineers, Part B: Journal of Engineering Manufacture 221, 12 (2007) 1725–1732. [CrossRef] [Google Scholar]
S. Junk, G. Hirt, I. Chouvalova, Forming strategies and process modelling for CNC incremental sheet forming, CIRP Annals-Manufacturing Technology 53, 1 (2004) 203–206. [CrossRef] [Google Scholar]
H. Meier, V. Smukala, O. Dewald, J. Zhang, Two point incremental forming with two moving forming tools, Key Engineering Materials 344 (2007) 599–605. [CrossRef] [Google Scholar]
J.R. Duflou, B. Callebaut, J. Verbert, H.D. Baerdemaeker, Improved SPIF performance through dynamic local heating, International Journal of Machine Tools and Manufacture 48, 5 (2008) 543–549. [CrossRef] [Google Scholar]
H.Y. Wu, C.H. Chiu, J.Y. Wang, S. Lee, Effect of lubrication on deformation characteristics of a superplastic 5083 Al alloy during bi-axial deformation, Materials Science and Engineering: A 427, 1 (2006) 268–273. [CrossRef] [Google Scholar]
M. Serenelli, M. Bertinetti, P. Turner, J. Signorelli, A theoretical study on forming limit diagram predictions using viscoplastic polycrystalline plasticity models, Key Engineering Materials 473 (2011) 327–334. [CrossRef] [Google Scholar]
Cite this article as: Lihui L, Kangning L, Cai G, Yang X, Guo C & Bu G: A critical review on special forming processes and associated research for lightweight components based on sheet and tube materials. Manufacturing Rev. 2014, 1, 9.
ePUB (833.2 KB)
Forming limit diagram prediction of 6061 aluminum by GTN damage model
Mechanics & Industry 19, 202 (2018)
Experimental Research of the Usability on Double Acting Intensifiers in Hydroforming
Analysis of the strain behaviour of a friction stir processed superplastic aluminium alloy
Deformation behaviour of laser-welded tube blank of TA15 Ti-alloy for gas forming at elevated temperature
A technology to improve formability for aluminum alloy thin-wall corrugated sheet component hydroforming
Manufacturing Review
Editor-in-Chief: Yi Qin (UK) - Editorial board


text:
IMPROVEMENT OF HEAT BALANCE OF SAND-LIME BRICK FAÇADE
Betonseal is the official representation of Innerseal and Topseal for Germany, Austria, Holland, Belgium and Luxemburg and is the leading company for Bio Gas Silo all over Europe.
www.betonseal.de
CONTROLL®TOPSEAL
The facade of a single-family house was cleaned with a high-pressure Jet device and after the complete drying once treated with Controll®Topseal. To prove that by draining with Controll®Topseal also heating and energy costs can be reduced, a thermograph examination of the facade conducted prior to treatment to the 07.03.2009 and a year later the 03.03.2010. 2009, temperatures were for example at the entrance test point T1 at 1.6 ° C, 2010 at 0.1 ° C. Point T2, 1.2 ° C was measured in 2009, in 2010, there were 0.5 º C. T3 2009 amounted to 2.0 ° C, 2010 at 1.7 ° C. Therefore, an improvement was achieved by an average of 51%.
Controll®Topseal includes water-soluble potassium Methylsilanetriolate with organic catalyst, which a deep penetrating allows up to 6 cm. As a result are back circulating prevents and frost spalling (E.g. through chill - dew - change) impossible. In addition, it increases the chemical resistance of mineral building materials.
Controll®Topseal is non-toxic and therefore not distinguishing mark according to the hazardous substances regulation. It is colourless, odourless, solvent-free, non-flammable and bio-degradable. Leave no film coating, but a transparent, clear and natural interface.
Controll®Topseal makes a strong water and dirt-resistant surface that prevents moss, fungus or algae infestation and is very easy to clean. The subsoil treated with Controll®Topseal is still protected against efflorescence, environmental factors (air pollution) and UV rays.

redpajama_set_name: RedPajamaCommonCrawl


text:
<?xml version="1.0" encoding="utf-8" ?>
<Recipe xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  xmlns:xsd="http://www.w3.org/2001/XMLSchema"
  Name="UnsecuredApplicationPage"
  xmlns="http://schemas.microsoft.com/pag/gax-core"
  Bound="false">
	<DocumentationLinks>
		<Link Caption="UnsecuredApplicationPage" Url="http://msdn.microsoft.com/en-us/library/ms463449.aspx" Kind="Documentation"/>
	</DocumentationLinks>
	<xi:include href="../../../TypeAlias.xml" xmlns:xi="http://www.w3.org/2001/XInclude" />
	<Caption>Unrestricted Layouts Page</Caption>
	<Description>Add a unsecured layouts page to the project inherited from LayoutsPageBase</Description>
	<HostData>
		<Icon File="Help/Icons/icon_UnrestrictedPage.ico" />
		<CommandBar Menu="SPSFProjectApplicationPages"/>
		<spsf:MetaData
		  Visible="true"
		  BindingType="CustomizationReference"
		  BindingTypeTemplate="CustomizationReferenceTemplate"
		  TestType="BaseCustomizationRecipeRunner"
		  Enabled="true"
		  CreateVSTemplate="true"
		  NotSandboxSupported="true"
		  Category="ApplicationPages" xmlns:spsf="http://spsf.codeplex.com">
			<spsf:Authors>
				<spsf:Author>Torsten Mandelkow</spsf:Author>
			</spsf:Authors>
			<spsf:VersionHistory>
				<spsf:VersionHistoryEntry>1.0 Initial Recipe</spsf:VersionHistoryEntry>
			</spsf:VersionHistory>
			<spsf:WebPageContent>
				<![CDATA[]]>
			</spsf:WebPageContent>
			<spsf:Test>
				<spsf:TestCases>
					<spsf:TestCase Name="DefaultApplicationPage">
						<spsf:TestCaseArguments>
							<spsf:TestCaseArgument Name="ApplicationPageName">DefaultUnsecuredApplicationPage</spsf:TestCaseArgument>
							<spsf:TestCaseArgument Name="ApplicationPageTitle">Custom Unsecured Application Page</spsf:TestCaseArgument>
							<spsf:TestCaseArgument Name="ApplicationPageDescription">Description of Custom Unsecured Application Page</spsf:TestCaseArgument>
						</spsf:TestCaseArguments>
						<spsf:TestExpectedDeployResults>
							<spsf:TestExpectedDeployResult Type="ManualCheck">Application Page with title 'Unsecured Application Page' exists in site /_layouts/SolutionName/DefaultUnsecuredApplicationPage.aspx</spsf:TestExpectedDeployResult>
						</spsf:TestExpectedDeployResults>
					</spsf:TestCase>
					<spsf:TestCase Name="AnonymousApplicationPage" Type="SolutionTestCase">
						<spsf:TestCaseArguments>
							<spsf:TestCaseArgument Name="ApplicationPageName">AnonymousApplicationPage</spsf:TestCaseArgument>
							<spsf:TestCaseArgument Name="ApplicationPageTitle">Anonymous Application Page</spsf:TestCaseArgument>
							<spsf:TestCaseArgument Name="ApplicationPageDescription">Description of Anonymous Application Page</spsf:TestCaseArgument>
							<spsf:TestCaseArgument Name="ApplicationPageAllowAnonymous">True</spsf:TestCaseArgument>
						</spsf:TestCaseArguments>
						<spsf:TestExpectedDeployResults>
							<spsf:TestExpectedDeployResult Type="ManualCheck">Application Page with AllowAnonymous = true and title 'Anonymous Application Page' exists in site /_layouts/SolutionName/DefaultUnsecuredApplicationPage.aspx</spsf:TestExpectedDeployResult>
						</spsf:TestExpectedDeployResults>
					</spsf:TestCase>
				</spsf:TestCases>
			</spsf:Test>
		</spsf:MetaData>
	</HostData>
	<Arguments>

		<xi:include href="../../BaseArguments.include" parse="xml" xpointer="xmlns(p=http://schemas.microsoft.com/pag/gax-core) xpointer(/p:Arguments/*)" xmlns:xi="http://www.w3.org/2001/XInclude" />

		<Argument Name="ResourceKeyPrefix" Required="true">
			<!-- provides the unique key with removed special chars -->
			<ValueProvider Stage="OnBeforeActions" RecipeArgument="ApplicationPageName" Type="ConvertedStringProvider" />
		</Argument>

		<Argument Name="ApplicationPageName"  Required="true">
			<Converter Type="NamespaceStringConverter" />
			<ValueProvider Type="VisualStudioCreateItemName" DefaultValue="ApplicationPage1" />
		</Argument>
		<Argument Name="ApplicationPageTitle" Required="true">
			<ValueProvider Type="Evaluator" Expression="Page Title" />
		</Argument>
		<Argument Name="ApplicationPageDescription" Required="true">
			<ValueProvider Type="Evaluator" Expression="Page Description" />
		</Argument>

		<Argument Name="ApplicationPageAllowAnonymous" Type="System.Boolean">
			<ValueProvider Type="Evaluator" Expression="false" />
		</Argument>

	</Arguments>
	<GatheringServiceData>
		<Wizard xmlns="http://schemas.microsoft.com/pag/gax-wizards" SchemaVersion="1.0">
			<Pages>
				<Page Width="600" Height="400">
					<Title>Layouts Page Name</Title>
					<Fields>
						<Field Label="Branding" ValueName="SPSFBranding" PanelType="SPALM.SPSF.Library.BrandingPanel, SPALM.SPSF.Library" />
						<Field ValueName="ApplicationPageName" Label="Page Name" >
							<Help>Enter name of the application page without extension (.aspx)</Help>
						</Field>
						<Field ValueName="ApplicationPageTitle" Label="Title" >
							<Help>Enter the title of page (displayed on top of the page and in the title of the html).</Help>
						</Field>
						<Field ValueName="ApplicationPageDescription" Label="Description" >
							<Help>Enter the description of page (displayed on top of the page).</Help>
						</Field>
						<Field ValueName="ApplicationPageAllowAnonymous" Label="Allow Anonymous Access" />
					</Fields>
				</Page>
			</Pages>
		</Wizard>
	</GatheringServiceData>
	<Actions CoordinatorServiceType="ConditionalCoordinator">

		<xi:include href="../../BaseStartingActions.include" parse="xml" xpointer="xmlns(p=http://schemas.microsoft.com/pag/gax-core) xpointer(/p:Actions/*)" xmlns:xi="http://www.w3.org/2001/XInclude" />

    <Action
		  Name="AddASPXPage"
		  Type="AddSPDataTemplateAction"
      SPDataName="$(ApplicationPageName)"
      SPDataCategory="ApplicationPages"
      SPDataTemplate="Text\GenericSPData\SharePointProjectItem.spdata.t4"
		  TemplateFileName="Text\UnsecuredApplicationPage\UnsecuredApplicationPage.aspx.t4"
		  TargetFileName="$(ApplicationPageName).aspx"
      DeploymentType="TemplateFile"
		  DeploymentPath="Layouts\$(SafeAppName)"
		  Open="true">
      <Output Name="CreatedProjectItem" />
      <Output Name="CreatedProjectFolder" />
    </Action>

		<Action
		  Name="AddASPXCode"
		  Type="AddTemplateToItemAction"
		  DeploymentType="CustomCode"
		  TemplateFileName="Text\UnsecuredApplicationPage\UnsecuredApplicationPage.cs.t4"
		  TargetFileName="$(ApplicationPageName).cs">
			<Input Name="ParentProjectItem" ActionOutput="AddASPXPage.CreatedProjectItem" />
		</Action>

		<Action
		  Condition="$(AutoCreateResxFiles)"
		  Name="AddResources"
		  Type="AddTemlateToResourcesFileAction"
		  ApplicationResources="true"
		  TemplateFileName="Text\UnsecuredApplicationPage\Resources.resx.t4"
		  ResourcesFileName="$(ResourceFilename).resx">
		</Action>

		<xi:include href="../../BaseFinalActions.include" parse="xml" xpointer="xmlns(p=http://schemas.microsoft.com/pag/gax-core) xpointer(/p:Actions/*)" xmlns:xi="http://www.w3.org/2001/XInclude" />

	</Actions>

</Recipe>

redpajama_set_name: RedPajamaGithub


This study identifies the Malaysian suburban young teenagers' behavior on internet usage: types of information, online activities, and internet topic of interest. This study also investigates the relationship between gender and internet usage behavior. A set of 350 questionnaires have been distributed to a group of young teenagers' age 11-12 years old in Year Six of primary schools in suburbs of Selangor. A total of 297 completed responses have been received and analyzed using Microsoft Excel and SPSS. The findings indicate that although young teenagers at suburban prefer to search entertainment information, do leisure activities and are interested in non-serious topic, most of the time, they still search information, do online activities and interested on educational information at other time. Further research can be conducted on information content preferences of young teenagers in other parts of Malaysia.


Inventory as of Feb. 1, 2018: 5000 Seeds.
The Eastern White Pine is a beautiful landscape pine widely used throughout much of North America. It is a fast growing species with bluish or greenish foliage depending on the individual tree. Both Maine and Missouri have chosen it as their state tree. It ranges in height from 50 to 80 ft. It's width ranges from 25-35 ft. It's cold hardy to zone 3. It prefers moist, well-drained soil and cool conditions. It also preferes full sun.
Scarification: Soak in water for 48 hours, change water each day. Stratification: Cold stratify for 60 days. Germination: Sow seed 1/4" deep, tamp soil, and mulch seed bed.


text:
Buffalo Man Previously Convicted On Federal Drug Charge Arrested For Possessing Guns | USAO-WDNY
BUFFALO, N.Y.-U.S. Attorney Trini E. Ross announced today that Nikita Burt, 38, of Buffalo, NY, was arrested and charged by criminal complaint with being a felon in possession of firearms. The charge carries a maximum penalty of 10 years in prison and a $250,000 fine.
Assistant U.S. Attorney Timothy C. Lynch, who is handling the case, stated that according to the complaint, members of the Drug Enforcement Administration and the Buffalo Police Department executed a search warrant at a Mortimer Street residence, an address known to be utilized by Burt. During the search, three handguns with defaced serial numbers were recovered. In 2013, Burt was convicted on a federal charge of distributing crack cocaine and is legally prohibited from possessing firearms.
The defendant made an initial appearance before U.S. Magistrate Judge H. Kenneth Schroeder, Jr. and is being held pending a detention hearing on January 19, 2022, at 3:00 p.m. before Judge Schroeder.
The criminal complaint is the result of an investigation by the Drug Enforcement Administration, under the direction of Acting Special Agent-in-Charge Timothy Foley, New York Field Division, the Buffalo Police Department, under the direction of Commissioner Byron Lockwood, and the Bureau of Alcohol, Tobacco, Firearms, and Explosives, under the direction of Special Agent-in-Charge John B. Devito, New York Field Division.


Fill out our contact form and we'll be happy to make an offer, or we can advise you on what it is probably worth.
What Is Your Cask Worth?
Please complete as much information as you can and we will e-mail you, by return, with a valuation. Please note that we may need to contact you for further information before making our final valuation. We may also need to re-gauge your cask before a valuation can be made.
If the cask is older than about 10 years old not many people would be willing to buy it off you without having recently checked the quantity in the cask. This usually costs about £25.00, depending on the warehouse where your cask is stored, but it is beneficial to both the buyer and yourself to know the quantity involved.
Prices tend to be "per litre of pure alcohol" so as the whisky gets older, say above 15-20 years, 5-10 litres of alcohol (10-20 litres) difference between an estimate and what is actually in the cask can be the difference between a profit or a very large loss. Taking such risks is not for the faint hearted so re-gauging is the only way for buyer and seller to both be confident.
If the cask is mature we are happy to consider deals where you get a specified number of bottles from the cask; labelled and Duty Paid. This allows you to taste the final product from your investment while not being stuck with 300 bottles of the same whisky in your garage!
We do not, as a general rule, sell bottles for other people, splitting shares of profits etc. This is too complicated and we are unlikely to agree on the value or selling price of the bottles because at Whiskybroker, we prefer to sell bottles cheaply and sell them quickly.


Microsoft is not only working hard on Windows 7 and SP2 for Windows Vista and Windows Server 2008. In fact, a new variant of Windows Server 2008, Windows Server 2008 R2 is been actively developed, and is been introduced at the 2008 PDC (Professional Developers Conference) as the server variant of Windows 7 (download 32-bit Windows 7 pre-beta or 64-bit Windows 7 pre-beta).
Microsoft Windows Server 2008 R2 will be the next version of the Windows Server operating system from Microsoft. Building on the features and capabilities of the current Windows Server 2008 release version, Windows Server 2008 R2 enhances on the features, security, reliability and performance to make the operating system that are easier to plan, deploy, and manage than previous versions of Windows Server.
Some of the features of Windows Server R2 include improved web application platform, enhanced virtualization and consolidation capabilities, reduced power consumption, streamlined management with new set of management tools, decreasing boot time, improved efficiency of I/O operations, improved speed of storage devices, especially iSCSI, new Active Directory capabilities such as a "recycle bin" for deleted AD objects, a new FTP server, and an increase in the number of supported processing cores from 64 to 256, scalability and reliability. There is also improvements to the Server Core installation option, which include the complete removal of the graphical environment from the operating system, and support for the .NET Framework, including ASP.NET applications and Windows PowerShell support.
For system administrators or clients who want to know more about Windows Server 2008 R2, the Windows Server 2008 R2 Reviewers Guide provides a technical overview of the incremental features and functions that make Windows Server 2008 R2 the next-generation Microsoft Windows Server operating system and successor to Microsoft Windows Server 2008. This guide also provides information about the benefits Windows Server 2008 R2 offers diverse users, as well as information about different scenarios. Current, it's a pre-beta draft.


What does it mean to be a loyal shopper in today's market?
With so many options at retail it's understandably difficult to truly drive customer loyalty. Only 12-15% of customers are loyal to a single retailer. Interestingly, those customers generate 55-70% of sales. When a retailer does convert loyal customers, the benefits are exponential. With that said, developing an effective loyalty program in today's market means more than tracking just one consumer purchase. Marketers and retailers have to track the entire customer journey.
You need to understand your customer before they even step foot in your store— like when they're dreaming of a better product, a better service, or even a better life. For example, if you want to get fit, Lululemon has crafted a loyalty program for you. They offer free "Sweat With Us" classes around the world. No points. No jargon. Lulu understands you and wants to help you realize a lifestyle—come to a class, see your peers wearing the gear, and leave with a positive connection with the brand.
The opportunities for big wins and customer loyalty exist across the customer journey spectrum.
Loyalty programs offer brands the opportunity to truly know and understand their customer. To tailor offers and events reaching their target demographic in new ways. A popular trend amongst coffee shops is the Disloyalty Card. This program encourages and rewards exploration of "competitors." The sentiment being that if you're a coffee lover, you'll appreciate the trial and become loyal to the shop that gave you the opportunity to explore.
In some cases, making public business decisions that align with your brand and reflect your mission statement are a loyalty program all on their own. Consumers today want brands that are authentic, and are able to connect with their own lifestyles. REI's #OptOutside initiative is a great example. When it started, it was an internal program to give employees a paid day off to enjoy the outdoors instead of slogging through Black Friday. Today, it has evolved into something much larger: it's both a campaign and a rallying cry for those who choose to live a life outdoors. #OptOutside is the foundation of the REI Co-Op membership which invests in the future of the outdoors by giving back nearly 70% of its' profits. REI is winning loyalty by encouraging customers to do more than find the next best product, but to also find their passions in nature.
So what does this mean for your brand? Develop a program that helps customers achieve their dreams while also bringing them back to your brand again and again. That program will turn the customer journey into a customer cycle. Brands like Nike take achievement seriously. Your workouts now unlock rewards. Earn rewards by making healthy lifestyle choices. This is a far cry from the points systems of the past.
Social currency is hard to define but continues to be the future of brand loyalty. The opportunities for big wins and customer loyalty exist across the customer journey spectrum. Decide what your brand stands for and take advantage of some of these novel approaches. Don't simply reward brand purchases, reward brand engagement. That will help your reward program stand out in the sea of sameness and help increase your sales exponentially.


text:
Q: Cannot update my existing older answer (S,PCCTC error) I am trying to be a good community member and update my answer to https://stackoverflow.com/questions/4055838/best-commercial-html-to-pdf-c-sharp-component on SO with the latest information from my current research.  However, the blacklist rules have changed since my last update and now I can't update my answer with the latest Q1 2012 information.
An experiment to remove all of the content and slowly add it back in section by section (to determine the offending nuggets) carries the risk that the existing answer would not be allowed back in, so I am cautious to undertake that bit of science.
My question is, do I have too many links (21)?  Are there blacklisted sites among the links?  Should I remove the links and let users find the companies on their own in the hopes that the content will pass muster?  I figured it would be a timesaver and I have already done the research.
I totally understand the rationale behind the design choice behind restricting content, blacklisting sites and NOT telling the user why their content is offending SO.  I've also read the following:
I am trying to fix up an answer, but I am told that "posts can't contain that content."
Why do I get: Sorry, posts can't contain that content
"Posts can't contain that content" messages fail to point out the offending part of the content
"Sorry, posts can't contain that content" message is a guessing game with no shells
"Sorry, posts can't contain that content." what content exactly (besides lmgtfy)
Comments can't contain this content?

redpajama_set_name: RedPajamaStackExchange


In the simplest terms, a landing page is any web page that a visitor can arrive (or, you know,"property on"). Landing pages would be the ideal way for companies to turn internet visitors into either leads or salesnonetheless, while many companies use landing pages, these pages are under-utilized. Research suggests that 62 percent of these businesses use only six or fewer landing pages within their marketing strategies.
Too frequently, website visitors fail to convert since their click sends them to the homepage rather than a particular landing page that guides them through the sales funnel. An effective strategy can enhance conversions by 48 percent or more. Don't get left behind. Here's why every modern marketer needs to incorporate landing pages in their digital marketing strategy. Conversions – Your website is to provide customers with an engaging and tailored encounter since it is those experiences that cause sales. Landing pages are the bread and butter of website endings. When people receive targeted content, they are more likely to take another step, like filling out a contact form or buying a product. Lead generation – Nothing leaves gathering online leads easier than landing pages on your website. Links which are distributed through different channels such as social websites, email, and search traffic are dropped to your website's homepage. Reclaim those lost leads by steering visitors to your landing pages. SEO value – When is the last time you visited the second page of search results? Do you remember? More landing pages means more opportunities to rank high in searches. If you rank high, you convert high. It is worth it to be in the top. Literally. Collect demographic information – If a lead becomes a conversion, then you get valuable information about who is visiting your site. That information allows you to target your audience in a more direct and efficient method. Content to pair with advertising features – Marketing offers can have a hard time finding a house on your website. Offers seek to incentivize users to purchase your service or product. So naturally, the ideal location to put them would be with webpages designed to convert. If you are searching to generate more prospects, rank high in research, score more conversions, pinpoint your demographic, and increase the effectiveness of your marketing offers, then it is time to develop a killer landing page strategy.
ClickFunnels, a sales funnel building applications, gives companies an easier way to market and deliver their services and products. ClickFunnels makes the process much simpler for a company to market, by offering pre constructed funnel options for products and services.
With ClickFunnels, it's easy to make a marketing and sales funnel from the ground as it incorporates all the core elements necessary to possess practical and effective sales funnel. Typically using the older more traditional revenue funneling softwares, you might need to fret about all of the components. Together with ClickFunnels, this really is all in 1 place, which makes it much simpler and cheaper than conventional funnels. ClickFunnels incorporates all these and much more, offering them at a comprehensive, unified bundle so you won't have to manage them one by one. So long as you have a company, ClickFunnels has that funnel that's great for you.
ClickFunnels is our favorite tool, as|since} it simplifies the whole revenue and marketing funnel procedure for businesses.There are so many different sorts of revenue funnels. Every one of these needing to be created specifically for a specific client. Consequently, they should be assembled in a manner that they draw your preferred customer. There are funnels for webinars, revenue, membership websites, and contributor listing and every 1 is quite different from another. Inside ClickFunnels, users can select from many different pre-built attachment options. It is as straightforward as choosing the one which aligns best with your company. If you're attempting to push an e-book, the approach should be much different than if you're expecting to market a subscription. Even if the last result of attempting to generate a sale is the same. ClickFunnels saves you time and attempt to start organizing your earnings funnels from scratch and accelerate your sales funnel installment. At any time you've chosen your funnel, then you need to acquire a template. With ClickFunnels, you're treated to many different templates and all of these are tested and proven to work. Having a throng of tested and proven templates available, ClickFunnels accelerates your A/B testing interval as you don't need to weed out templates which aren't performing. You can easily integrate videos, videos or animations in your template utilizing ClickFunnels easy to use interface. Then you may start doing your A/B testing to ascertain what works and what does not.
Thanks for staying to the end… hope you found what you were looking for regarding landing pages designs!!


On-Track Software Series reviewed by PC Magazine.
Covering preschool to third grade, the 12 electronic workbooks in the On-Track Software Series provide a fun way for kids to enhance their skills. The series includes math, reading, spelling, and more. Each CD presents easily understood audio instructions for the many games, puzzles, and other activities. School Zone bundles a workbook with each CD; the reading programs also include illustrated books.


Hi – from Norway! I will very much like to share with you a recipe for Goro – without rolling, a modern and easier recipe.
Whip egg and sugar. Stir in the melted butter. Whip the cream and stir it carefully into the mixture. Use spoon to drop the mixture in the hot "gorojern", one spoon in each "room".
I have tried to translate to the best of my ability!


Thinking of sending your child off to preschool? There's a long list of reasons why that could be a very good idea.
What's not to like about being off-duty while knowing that your child is in a safe, caring environment? Happily, that's just one of many perks of starting preschool. Preschool gets the littlest students ready for the big-time learning that will begin in elementary school (hence the "pre") — minus the formal instruction and more serious structure that's best left to the over-5 crowd. At a good preschool, your child will pick up new skills the age-appropriate way — by doing, playing and exploring.
Practice with social skills. By taking part in sing-alongs and story time, hands-on art projects and simple experiments, dress-up and building-block sessions, 2- to 5-year-olds gain experience taking turns, following directions and cooperating with their peers. One of the other benefits of preschool: Social butterflies who may be bored at home can spread their wings in a group setting, while wallflowers who aren't born minglers may blossom when they're part of the preschool pack.
Introduction to the basics. Preschool benefits include exposure to numbers through counting blocks, to language skills during story and singalong time, to basic math concepts through cooking, and to colors through finger-painting. In other words, your child will engage in fun (and sometimes messy!) activities that boost her curiosity and knowledge in a pressure-free way. Your child will also glimpse botany, biology and geology during nature walks; shapes by putting puzzles together; and the seasons through collages (and just going outside!).
Learning about the wider world. The more your child plays, explores and sees for himself, the more he'll learn. At preschool, the opportunities for discovery are limitless. At the water table, he'll figure out that some objects sink and others float; on an autumn nature walk, he'll see that leaves dry up and fall down; in the playground, he'll learn that trikes are easier to ride on smooth surfaces and harder on rough ones.
A chance to create. Preschool teachers have tons of arts-and-crafts projects up their rolled sleeves. Your little artist will have more chances to channel his inner Picasso at preschool than he'd have at home (plus, you won't have to clean up after him!).
Lots of fun. Sure, you have loads of toys, books and activities at home. But at preschool, your little one will have at his chubby fingertips a plethora of playthings — a veritable wonderland of fun and games (and don't forget, at this age fun is the name of the game).
Expert direction. While you are your child's first and most influential teacher, she (and you) will have lots to learn, too, from the professionals (who happen to be trained in child development).
So now that you know what your child will get out of a good program (and you may find even more benefits once your cutie's in class), it's time to set out to find the right preschool. Check out the stories in this section to learn about preschool options, how to pick a good preschool program, and how to set the scene for a smooth school year for your soon-to-be-school kid.
American Academy of Pediatrics, Cognitive Development in Preschool Children, November 2009.


text:
The lure of ESOPs
Written by Eleanor Beaton
Don White can still taste the frustration 10 years later. As a manager at an Alberta-based distribution firm, White hired, trained and ultimately lost dozens of workers to employee-owned businesses, which could offer something White's former employer didn't: a share in the firm's success. "I knew that when I started my own company, I wouldn't do it without an employee-owned structure," says White, who now runs Apex Distribution Inc., which ranks 94th among this year's PROFIT 100 companies. "I saw it as an important way to keep good people."
Smart CEOs are always on the lookout for tools that will help attract, motivate and retain top talent, especially in today's ever-tightening labour market. This year's survey of Canada's Fastest-Growing Companies shows that PROFIT 100 leaders consider employee share-ownership plans (ESOPs) part of the solution. Almost half (47%) of them run ESOPs and say they attract and keep workers, facilitate succession planning and boost productivity. (According to the Oakland, Calif.-based National Center for Employee Ownership, employee-owned firms enjoy 4% to 5% annual productivity gains in the first few years of an ESOP, double that of companies that aren't employee-owned.) That said, a poorly structured or haphazardly communicated ESOP can splinter employer/employee trust and erode your workplace culture.
In the U.S., ESOPs take on specific, legalized structure; in Canada, the term is more loosely applied to include any plans that allow employees to purchase or be granted shares in their firm. Most ESOPs use a combination of three components: employees can purchase shares outright via share-equity plans; they can be given stock options; or, they can be granted "phantom" shares, for which dividends are paid but title isn't legally transferred from employer to employee.
Don White stayed true to his beliefs. When he co-founded Calgary-based Apex Distribution in 1999 with two colleagues, he immediately hired a business valuator and lawyers to help put an ESOP in place at his privately held firm. White set aside a specific number of shares for purchase by his top salespeople, as well as employees at each branch of the firm; shares were added as the company grew, and new employees were allocated shares based on their role in the company. Today, the $200-million-a-year distributor of oil-and-gas drilling equipment has 3.8 million shares outstanding, about 50,000 of which change hands during its semi-annual trading periods. While some firms set up "golden handcuff" plans, in which shares have multi-year vesting periods in order to retain staff, White says his firm has had low turnover, despite allowing employees to sell their shares at any time. Of Apex's 250 employees, 130 own a piece of the firm; the others have chosen not to buy shares, because they can't afford to, are new to the firm or, in White's words, are "averse to any type of investing."
ESOP design will vary depending on your province and whether your firm is publicly traded. (The Toronto Stock Exchange, for example, requires its listed firm to follow clear guidelines on how ESOPs are built and run.) Generally, there are four primary considerations: valuation (to determine the price and number of shares that should be issued), design, taxation and legal implications. "It definitely took us awhile to understand how [the ESOP] was supposed to work," admits White. "I spent a lot of time trying to figure out valuation and share prices." The effort was worth it: Apex has had zero turnover in top management and sales positions, contributing to its recent year-over-year revenue growth of 100% in 2006 and 50% in 2005.
Of course, it hasn't been an entirely smooth ride. In fact, Apex fell prey to a common pitfall in ESOP execution: a dispute among owners about how much of the company should be up for grabs by employees. As the company grew, White says his co-founders, a pair of brothers, wanted to restrict shares to a small group of employees, whereas White wanted to keep the plan more broad-based. They couldn't agree, tensions rose and, after a falling-out, the brothers sold their shares and left the firm.
The episode fractured employee morale in the ensuing months. "First, we told them we were going one way," says White, "and then it seemed as though we were going another." However, White's fight to keep the firm employee-owned has paid off handsomely. While private firms rarely see the Googlesque share-price explosions of public companies, ESOPs at private firms can nevertheless create new wealth for employee shareholders. Apex's share value has risen from 80¢ in 2001 to $6 today, leaving some employees with retirement windfalls of more than $200,000. As for White: "Any dilution I've made has been compensated by our share price."
Another key element in a successful ESOP is employee participation, say Perry Phillips, president of Thornhill, Ont.-based employee-ownership consultancy ESOP Builders. "There's a huge morale spike after an ESOP gets implemented," says Phillips. But if employees aren't given the chance to participate in decision-making, they could become disenchanted and less productive. To create an ownership mentality among your staff, it's important to link job performance to margins and share value. Sharing financial statements — and explaining what they mean — is also a must.
You should also pursue external validators of success. "It's important for employees to know that their company is successful, that their shares are worth something," says Mark Chaplin, CEO of Langley, B.C.-based Disc Go Technologies Inc. (No. 19), a manufacturer of CD- and DVD-repair machines. Chaplin exercises all opportunities to boost the visibility of his firm, whose ESOP dates back to 2004. He enters Disc-Go-Tech for consideration in programs that can generate publicity, such as the PROFIT 100, and retains an outside PR firm to drum up attention. Combined with monthly meetings at which he briefs all employees on company performance, Chaplin says, the PR helps highlight the value of owning a piece of Disc-Go-Tech.
When Chaplin and his two co-founders set up the ESOP, they made their motives clear: succession planning. In fact, being transparent about your reason for starting an ESOP is crucial to its success. A lack of employer/employee trust is a major reason why ESOPs underachieve. "We never saw ourselves running this company indefinitely," says Chaplin. "We wanted to be totally up front about it with our employees." The Disc-Go-Tech co-founders see two major options: going public or being purchased by a customer. "If we didn't have an ESOP in place," says Chaplin, "our employees might feel they'd automatically lose their jobs. This is a kind of protection."
Jason DeZwirek says that his company's ESOP has been essential to its U.S. expansion. In the early part of the decade, Kaboose Inc. (No. 16) of Toronto, began a series of acquisitions that helped transform it into North America's largest independent family-oriented online media company. The firm needed top talent, but couldn't afford to pay top dollar. Granting options proved a "very important tool" in luring people away from the likes of Warner Bros., Disney and Yahoo!. "[U.S. workers] are extremely focused on it," DeZwirek says. "They'll ask about it in job interviews."
The key to creating a successful plan, he believes, is to be judicious in how you grant shares and how much equity you give away. At Kaboose, employee options are decided by the board on a case-by-case basis, and are almost always attached to milestones: the employee, her department or the firm as a whole must reach specific performance targets.
Since Kaboose went public in 2005, it has been particularly vigilant about the amount of stock granted to employees, holding employee ownership at 10%. For growing firms, Phillips says, it's a good idea to limit the ESOP to 10% to 15% of total stock in the beginning. Devote too many shares to your ESOP, and you risk having too little equity to leverage into future growth capital. If growth financing is less of an issue, particularly if you're using the ESOP as an exit strategy, you may choose to start with as much as 20%.
DeZwirek says Kaboose wouldn't have been able to grow as dramatically as it has without employee ownership. But he also warns of the dangers of creating too much wealth for your employees overnight. "If you grant them too large an option, they may want to leave to do something else," he says. "Look at the terms of your options and make sure you're balancing morale with retention."
ESOP snapshot
An employee share-ownership plan can have a profound effect on your company. Although it's 20 years old, the most definitive study of ESOPs in Canada, conducted by the Toronto Stock Exchange, revealed that firms with ESOPs are more productive and profitable than their non-ESOP counterparts. ESOP companies in the study experienced:
€¢ 123% higher five-year growth
€¢ 95% higher net profit margin
€¢ 24% higher productivity (measured by revenue per employee)
€¢ 92.3% higher return on average total equity
€¢ 65.5% higher return on capital
FILED UNDER: ProfitGuide strategy


text:
Previously sunken boats are emerging at Lake Mead as water disappears
By Rachel Ramirez
Updated 4:15 PM EDT, Tue May 24, 2022
A formerly submerged boat sits high and dry along the shoreline of Lake Mead.
John Locher/AP
The water level in Lake Mead — the nation's largest reservoir — dropped below 1,050 feet elevation for the first time last week, a critical milestone that signals more stringent water cuts are around the corner for the Southwest.
If the US Bureau of Reclamation determines in its August report that the lake level will be at or below that elevation in January 2023, the Southwest will move into the second tier of unprecedented water cuts that will further reduce the amount of Colorado River water that can be used by cities, industry and tribal water users.
As of Tuesday, Lake Mead's level was around 1,049 feet above sea level.
As the water level drops, formerly sunken boats are emerging in the mud, and other vehicles are getting newly stuck.
Travis Pardee, who took several photos of the boats, told CNN he believes there are dozens in the area, but he only photographed a few of them.
Multiple boats resurface at Lake Mead as the water level falls.
Travis Pardee
Formerly sunk boats are resurfacing at Lake Mead as the water level drops.
And on Monday the National Park Service shared several photos on Twitter that showed trucks stuck in the mud around the lake – a shoreline that looks deceivingly stable, but acts more like quicksand.
"If you're struggling to maneuver your car, boat or yourself along the beach, immediately head to higher ground if possible," NPS said on Twitter. "No boat or car is worth a life."
A truck is stuck in the muddy shoreline of Lake Mead.
Lake Mead National Recreation Area/Twitter
As the shoreline has receded, it's left behind a bank of mud that looks deceivingly stable.
Future water cuts
Lake Mead, which provides water to roughly 25 million people in Arizona, Nevada, California and Mexico, is currently operating in a Tier 1 shortage, which began in January. Under Tier 1 conditions, Southwest states saw mandatory cuts in the water they could consume from the Colorado River. Those cuts have primarily affected agriculture.
If the lake's water level is expected to stay below 1,050 feet by January 2023, the more significant Tier 2 shortage would be implemented. Arizona would go from the current 18% cut to 21% and Nevada will go from 7% to 8%. Mexico will also see a 7% cut in its water.
Additional cuts — each tier with rising impact on agriculture and municipal water use — are expected if Lake Mead continues to fall. And if officials expect the level to be under 1,045 feet come January, then California too, would see a mandatory 5% cut from what they can pull from the Colorado River.
"This illustrates how truly bad the situation is," John Fleck, director of the Water Resources Program at the University of New Mexico, told CNN. "The climate change risk we face on the Colorado River basin right now has never been greater."
The West's megadrought
'The brink of disaster': 2023 is a critical year for the Colorado River as reservoirs sink toward 'dead pool'
See what extreme drought has exposed at Lake Mead
The West's historic drought is threatening hydropower at Hoover Dam
The Colorado River irrigates farms, powers electric grids and provides drinking water for 40 million people. As its supply dwindles, a crisis looms
Patti Aaron, the Bureau of Reclamation's public affairs officer, said the projections are nuanced, since water officials also have to account for the dwindling water levels at Mead's upstream neighbor, Lake Powell, the country's second-largest reservoir.
The agency recently announced unprecedented, emergency steps to help boost water levels at Lake Powell, which includes releasing more water from smaller upstream reservoirs on the Colorado River into Powell, while also holding back water in Lake Powell itself, instead of sending water downstream to Lake Mead.
Without those emergency steps, the bureau estimated there was about a 25% chance the Glen Canyon Dam, which is powered by Lake Powell, would have stopped producing by the end of this year. The dam generates power for as many as 5.8 million homes and businesses across seven states.
"Under the 2022 operational criteria, Glen Canyon Dam was supposed to release 7.48 million acre-feet of water to Lake Mead," Aaron told CNN. "It was determined to lower that release to 7 million acre-feet to help protect Lake Powell from reaching critical levels."
Given these recent unprecedented actions, "it is impossible to say what exactly will happen between now and August," she said, which is when the Lake Mead report is issued.
Carson, CA - May 17: California Governor Gavin Newsom speaks to the media after a tour of a Metropolitan Water District water recycling demonstration facility in Carson, CA. Tuesday, May 17, 2022. (Photo by Hans Gutknecht/MediaNews Group/Los Angeles Daily News via Getty Images)
Hans Gutknecht/MediaNews Group/Los Angeles Daily News/Getty Images
California governor pleads for more water conservation, warns of mandatory statewide restrictions
Water authorities across the affected states as well as the federal government are already bracing for what's to come.
"In preparation, we are continuing to work with the stakeholders, tribes, partners, and water districts to help them understand how much of a decline in their deliveries there might be," Aaron said. "We also fund conservation actions and activities across the [Colorado River] Basin."
As the climate rapidly changes and the drought persists, Fleck said the West should prepare for more shortages and take proactive actions.
"Whatever we do with moving water around from one reservoir to another reservoir, that's just a bandaid, what we really need to do is dramatically reduce the use of water in the basin," he said. "The heart of the problem is those reservoirs are empty because we've been using more water than the river can provide. We've got to turn that around."