1. Field of the Invention
The present invention relates to a method for tracking deformation of a metal part.
Correspondingly, it also relates to a device for tracking deformation of a metal part, suitable for implementing the method according to the invention.
In general, the present invention relates to the field of straightening or forming of a metal part.
2. Discussion of the Background
More particularly, it is applied to the straightening of aircraft parts, and especially parts of the structure of an aircraft.
In effect, as a result of residual stresses inherent to metal parts, such parts tend to become deformed during machining, thus necessitating an inverse deformation known as a straightening operation.
The straightening operations rely on the plastic deformation of a metal material. In effect, these materials have the property of undergoing irreversible deformation (permanent deformation) when they are subjected to mechanical stresses beyond a certain stress level known as the “elastic limit”.
In general, a press imposing what is known as “three-point” bending is used to achieve these straightening operations on large-size machined parts. In this way, the metal part to be deformed is held in place at two points, a pressure force being applied at a third point to produce permanent deformation of the part to be straightened.
When the pressure force is applied to the metal part, the deformation achieved frequently goes beyond the desired deformation, thus requiring the operator to perform an inverse straightening operation.
This leads to considerable straightening times, possibly to rupture of metal parts and above all to introduction of excessive residual stresses that may alter the fatigue strength of the metal parts and their ability to adapt during their subsequent use.