A simplified mode of residual stresses induced by punching

摘要

In the present work, we study residual stresses induced by the blanking process of thin sheets. Residual stresses are evaluated without modelling the whole cutting process, by building a plastic strain field deduced from the phenomenological analysis of the deformation mechanisms activated during the blanking process. It is found that a small tension effect, associated to an axisymmetric geometry, can create small, but long range residual stresses. This kind of effect clearly affects the magnetic behaviour of magnetic sheets used to build electrical machines.