A model for texture development dominated by deformation twinning: Application to zirconium alloys

Abstract In many polycrystals of less than cubic crystal symmetry, plastic deformation is dominated by twinning. In particular, we will treat the case of Zr and Zr alloys in detail. We propose a new method for modelling grain reorientation due to twinning, which is based on a Volume Fraction Transfer (VFT) scheme; the scheme is also applied to the slip modes. We find that this method predicts textures that are, when twinning is the dominant mode, considerably different from and in better agreement with experiment than the conventional schemes which reorient an entire grain when some criterion has been met. Various combinations of slip and twinning modes and of the associated critical stresses are systematically investigated for the case of rolling, tension and compression of Zr alloys. A comparison of various predicted and experimental textures leads to the conclusion that twinning must, indeed, be controlling texture development.