Polycrystal

neglecting polycrystal elasticity, but they considered initial texture and deformation induced texture evolution and kept the imperfection grove angle perpendicular to the principal loading direction (due to the limited computational power). In the later years, Wu et al., 1997 computed the FLDs for FCC polycrystals by employing the Asaro-Needleman crystal plasticity framework in which the imperfection grove was considered to be rotating with respect to the major biaxial stretch direction in the plane of the sheet metal. The effects of various parameters in the constitutive equations such as material strain-rate sensitivity index, single slip hardening, latent hardening, initial imperfection factor, initial imperfection groove orientation, texture and crystal elasticity were presented in detail by Wu et al., 1997. For the FCC polycrystals, using a crystal plasticity based model with Taylor-type homogenization scheme, Wu et al., 2004; Yoshida et al., 2007 showed that the typical recrystallization texture component (cube texture) improves the right side of the FLD (biaxial formability) while the rolling texture components (Copper, Brass, Goss and S textures) show a decline in the biaxial formability (Yoshida et al., 2007). Inal et al., 2005 used a rate-sensitive polycrystal plasticity model with the full constraint Taylor type homogenization scheme (FC-Taylor) and suggested that the effect of texture evolution during deformation on formability of body center cubic (BCC)…

recrystallization. This process equiaxed crystals through the nucleation and growth of new low stress and low dislocation density grains. This process causes the material to lose strength, thereby restoring ductility. Through a comparison between the data found in this lab and that in another, it was concluded that both had similar trends. The change in hardness shown in Figure #, match the data graphed figure # whereas cold working on the copper material increases, the greater the hardness of…