Experimental and by simulation analysis of residual stress and sprinback in the case of metal sheets forming by using the “three bars” method

Abstract

The experimental investigation of the residual stresses in the case of drawn parts is a difficult problem because of the complexity of forming operations and formed parts geometry. A solution of the problem can be than the simulation of the forming process and residual stresses distribution, but for a much more certitude of the results the simulation method must be experimental verified. An efficacious method proposed and used by Chandra (1993) and LMecA-ESIA Annecy consists in the experimental control of residual stresses for a simple case by applying the “three bars” method. Based on the experimental investigation, the results obtained from simulation can be compared and in the case of their coincidence a mathematical model can be than elaborated, adopted and extended for complex forming operations and formed parts. The paper presents the results obtained from such simulation and experimental investigation of residual stresses and springback generated in the case of metal sheets tensile