Effect of initial textures on deformation mechanisms and texture evolutions of Zr alpha polycrystals deformed by channel-die compression tests

Channel die compression tests were performed at room temperature on zirconium polycrystalline samples (Zr 702) up to 40% plastic strain. Three initial textures (T3, T4 and T5) with [c] axes concentrations along the die axes (ND, TD and LD) are considered. The macroscopic stress-strain curves, the active mechanisms (slip and twinning systems) and the texture evolutions obtained for T3, T4 and T5 show an anisotropic behaviour of the material. Identification of the deformation modes by EBSD (Electron Back Scattering Diffraction) indicates an important contribution of {<10(1)over bar 0>} prismatic glide in the different samples. Estimates of twinned volume fractions show an important activation of {<10(1)over bar 2>} twinning in the T5 samples. The correlation between the active mechanisms and the texture evolutions is partly explained by geometrical considerations. (C) 1997 Elsevier Science S.A.