Bauschinger effect in simple shear for DQIF and DP steel sheets

Abstract

Sheet metal forming commonly involves various processing steps leading to complex strain paths and large strains. A good description of the mechanical behavior of materials under complex loading condition helps to predict accurately the real forming process. The simple shear test is particularly suitable for sheet materials because strain-path changes can be simply conducted by reversing the tool displacement direction. In this work, forward and reverse simple shear tests are performed for the analysis of the hardening behavior of IF and DP steel sheets. The results indicate that both materials exhibit Bauschinger effects and strain hardening transients during reverse loading in all conditions investigated. The amplitudes of these effects increase with higher amounts of prestrain. DP steel, which contains martensite as second phase particles, shows a more pronounced Bauschinger effect, delayed occurrence of the transient stagnation region and permanent softening.