Embedded Grain Rotation and Roping of Stainless Steel

Abstract

The recent application of crystal plasticity calculations to electron backscatter diffraction (EBSD) data from ferritic stainless steel sheet has confirmed the presence of grain clusters parallel to the rolling direction (RD) with similar deformation tendencies. The results of these simulations provide strong support for the Takechi model of roping. The remaining question that has not yet been adequately addressed is how the deformation tendencies of grains/grain clusters are affected by being embedded within a three-dimensional medium. In this article, the behavior of individual grain orientations when embedded within media of differing crystallographic orientations is explored within the framework of a viscoplastic self-consistent (VPSC) model. It is shown that the tendency for out-of-plane shear exhibited by some grain orientations persists, even when the grains are embedded within a matrix that has very different deformation tendencies. This is further extended to examine the influence of the orientation of grain clusters in relation to the roping phenomenon.