Crystal Plasticity Analysis of the Relation between Micro‐Texture and Surface Ridging for a 21%Cr Ferritic Stainless Steel

Abstract

The micro‐texture of ferritic stainless steel generated by rolling and annealing processes is supposed to behave plastic anisotropy and heterogeneous strain response during forming, especially for the high Cr content ferritic stainless steel with single ferrite phase. The relation between crystallographic orientations and their strain responses during loading are analyzed for a 21% Cr ferritic stainless steel sheet. The crystallographic orientation distributions in surface and center layers as well as in cross section are characterized by an electron backscatter diffraction (EBSD) method. It indicates that texture gradients along thickness with center layer having a higher density of <111>//ND texture are formed. Some grain clusters with similar oriented grains gathering together to be parallel to the rolling direction are observed. Then, the experimental orientation distributions are condensed and incorporated into a developed crystal plasticity finite‐element model (CPFEM), in which the multiple slip systems and the interaction between neighbor grains are considered. The simulation results confirm that the heterogeneous distributions of normal strain and shear strain preserved for the different crystal orientation grains result in the surface ridging. The texture gradients can help to decrease the tendency of surface ridging. The simulation results show a reasonable agreement with the tensile test results.