A LOT of tosh is talked about “nanotechnology”, much of it designed to separate unwary investors from their hard-earned cash. This does not mean, though, that controlling the structure of things at the level of nanometres (billionths of a metre) is unimportant. In materials science it is vital, as a paper just published in Nature, by Hansoo Kim and his colleagues at the Pohang University of Science and Technology, in South Korea, demonstrates. By manipulating the structure of steel on a nanometre scale, Dr Kim has produced a material which has the strength and the lightness of titanium alloys but will, when produced at scale, cost a tenth as much. 
 
 Steel is useful because it is strong and cheap. But it is also heavy. It has, therefore, always been useless for applications such as aircraft. In a world that demands the ever-more efficient use of fuel in motor cars and lorries, it is now falling out of favour there, too. According to Dr Kim, the share by weight of steel in an average light vehicle fell from 68.1% in 1995 to 60.1% in 2011. 
 
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 The obvious way out of this is to alloy steel with a lighter metal. And the obvious one to choose is aluminium, which is, like iron (steel’s principal component), cheap and abundant. An alloy of iron, aluminium and carbon (steel’s other essential ingredient) is too brittle to be useful. Adding manganese helps a bit, but not enough for aluminium-steel to be used in vehicles. 
 
 Dr Kim and his colleagues have, however, found that a fifth ingredient, nickel, overcomes this problem. To a chemist, an alloy is a mixture of materials rather than a true chemical compound. But metals do sometimes react to form real compounds, and one class of these, known as B2 intermetallic compounds (which have equal numbers of atoms of two different metals within them), lies at the heart of Dr Kim’s invention. The nickel reacts with some of the aluminium to create B2 crystals a few nanometres across. These crystals form both between and within the steel’s grains when it is annealed (a form of heat treatment). 
 
 B2 crystals are resistant to shearing, so when a force is applied to the new material they do not break. This stops tiny cracks propagating through the stuff, which gives it strength. That strength, allied with the lightness brought by the aluminium, is what Dr Kim was after. 
 
 There is, of course, many a slip ’twixt laboratory bench and production line, but POSCO, one of the world’s largest steel companies, is sufficiently interested in Dr Kim’s discovery to be planning, later this year, a trial that will produce it at industrial scale. If that goes well, not only may steel’s retreat from cars be reversed, but a steel aircraft may one day take to the skies. 

 Annealed microstructure of high-specific-strength steel (HSSS). Fine FeAl-type B2 precipitates form during annealing in between the B2 stringer bands in steel matrix. The specimen was annealed for 15 min at 900 C. 
 
 Big news from the metallurgy desk this week: It looks like steel is about to get a lot steelier. 
 
 According to a report published today in the prestigious journal Nature, researchers in South Korea have developed a new recipe for making a high-strength, low-density steel alloy that can outperform titanium in terms of strength and ductility. 
 
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 In materials science, ductility is a measure of a substance’s ability to be stretched or bent without breaking. It’s a big deal in manufacturing — particularly auto manufacturing — because steel alloys designed to make the metal lighter usually result in a more brittle metal. 
 
 As a result, manufacturers looking to make lighter cars have turned to alternative materials. In statistics cited in the Nature report, the share by weight of steel and iron in an average light vehicle decreased from 68.1 percent in 1995 to 60.1 percent in 2011. 
 
 But the new steel alloy proposed by the South Korean team actually strengthens the steel in the same fabrication process that makes it lighter and more flexible. The specifics get pretty complicated, but the recipe essentially improves on existing steel-aluminum alloying processes. 
 
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 As such, deployment of the new technique could be rapid and the breakthrough could have wide-reaching implications in manufacturing, construction and engineering. 
 
 “The balance of lightness, strength and ductility in metallic alloys has been explored since the Bronze Age,” the research team writes in the Nature report. “There is increasing demand for a broad range of structural materials for environmentally benign, energy-efficient, lightweight engineering systems.” 
 
 via Nature 

 From shipping containers to skyscrapers to turbines, good old steel is still the workhorse of our modern world. Now, scientists are discovering new secrets to make the material better, lighter, and stronger. 
 
 Today a team of material scientists at Pohang University of Science and Technology in South Korea announced what they're calling one of the biggest steel breakthroughs of the last few decades: an altogether new type of flexible, ultra-strong, lightweight steel. This new metal has a strength-to-weight ratio that matches even our best titanium alloys, but at one tenth the cost, and can be created on a small scale with machinery already used to make automotive-grade steel. The study appears in Nature. 
 
 "Because of its lightness, our steel may find many applications in automotive and aircraft manufacturing," says Hansoo Kim, the researcher that led the team. 
 
 Bend, Don't Break 
 
 The key to creating this new super-steel was overcoming a challenge that had plagued materials scientists for decades. In the 1970's, Soviet researchers discovered that adding aluminum to the mix when creating steel can make an incredibly strong and lightweight metal, but this new steel was unavoidably brittle. You'd have to exert lots of force to reach the limit of its strength, but once you did, the steel would break rather than bend. 
 
 Scientists soon realized the problem: When creating the aluminum-steel alloy, they were occasionally fusing atoms of aluminum and iron together to form tough, crystalline structures called B2. These veins and nuggets of B2 were strong but brittle—until Kim and his colleges devised a solution. 
 
 "My original idea was that if I could somehow induce the formation of these B2 crystals, I might be able to disperse them in the steel," he says. The scientists calculated that if small B2 crystals were separated from one another, then the surrounding alloy would insulate them from splintering. 
 
 B2 crystals (light gray) are dispersed in the aluminum-steel alloy (dark gray.) Hansoo Kim 
 
 Kim and colleagues spent years devising and altering a method of heat-treating and then thinly rolling their steel to control when and where B2 crystals were formed. The team also discovered that adding a small percentage of nickel offered even more control over B2 formation, as nickel made the crystals form at a much higher temperature. 
 
 More Super-Materials to Come? 
 
 Kim's team has created the new metal on a small scale. But before it can be mass-produced, researchers must confront a tricky production issue. 
 
 This new metal has a strength-to-weight ratio that matches even our best titanium alloys 
 
 Currently, steelmakers use a silicate layer to cover and protect mass-produced steel from oxidation with the air and contamination from the foundry. This silicate can't be used for Kim's steel because it has a tendency to react with the cooling aluminum, compromising the final product. Before we starting building skyscrapers out of super-steel, they'll have to figure out a way to protect the material out in the real world. 
 
 It'll be worth it. The final product of all this tinkering "is 13 percent less dense compared to normal steel, and has almost the same strength-to-weight ratio compared to titanium alloys," Kim says. That's remarkable, but Kim insists that the method is actually more important than the result. Now that his results are published, he expects scientists to cook up a multitude of new alloys based on the B2-dispersion method.
– A group of South Korean scientists says it's finally come up with the perfect metallurgical cocktail to create a new form of steel that's flexible, lightweight, relatively inexpensive—and as strong as titanium, Popular Mechanics reports. The South Korean study published in Nature, which is being heralded by the researchers as "one of the biggest steel breakthroughs of the last few decades," as PM puts it, claims the strength-to-weight ratio of the new steel alloy matches that of the best titanium alloys and can be made at 10% of the cost. It will also reportedly be possible to churn out the steel on a smaller scale with currently existing equipment used to make automotive-grade steel, the researchers say. Steel is already a widespread building block, from framing out skyscrapers to its use in turbines and shipping containers. But scientists have scratched their heads for years on making it light enough for automotive and aircraft applications, as well as increasing an alloy's ductility—what Discovery describes as a material's "ability to be stretched or bent without breaking." Adding lightweight aluminum to the steel mix helps with the first issue, but scientists couldn't get around that alloy's brittleness. The Korean scientists figured out a way to separate bunched-up crystals inside the steel and spread them out so they'd be better protected from breakage. It may take awhile to transition these reported results into mass production, but steel giant POSCO is already curious enough to be planning a trial using the steel on an industrial scale, the Economist reports. (Scientists have added metal atoms to spider silk to create a super-strong web.)