Formability predictions and measurement of 316L stainless steel using self-consistent crystal plasticity

Abstract

A viscoplastic self-consistent (VPSC) crystal plasticity model was used to describe the mechanical behavior of a 316L stainless steel sample. Mechanical anisotropy of the 316L stainless steel was evidenced in the experimental results collected from the uniaxial tension tests along various directions. EBSD images were obtained from the as-received sample, and a representative population of discrete orientations was created to account for the initial crystallographic texture in the model. The hardening parameters were identified by using the flow stress-strain curve obtained from a bulge test. The model-predicted and experimental flow-stress curves and R-values were compared in order to estimate the adequacy of the VPSC model to describe the anisotropic behaviour of the 316L stainless steel sample. Furthermore, the crystal plasticity model, in conjunction with the Marciniak-Kuczyński approach, was used to predict forming limit diagram. The model was validated by comparing with the experimental flow stress curves from uniaxial tension and bulge tests. The predictive accuracy on forming limit diagram was also estimated by comparing with the experimental forming limit strains obtained through Nakajima tests.