DOI: 10.5176/2251-1857_M348
Authors: Gwénaëlle Proust
Abstract:
For hexagonal close-packed (hcp) metals, plastic deformation is accommodated by different slip and twinning modes. Various factors affect the activation of the deformation mechanisms: alloy composition, grain size, temperature of deformation, strain rate and loading direction. The multiplicity of deformation mechanisms that can be activated and the dependence on loading conditions explain the observed anisotropy on hardening behaviour and texture evolution. Modern microscopy techniques, such as electron backscatter diffraction, enable the quantitative analysis of twinning. Using such techniques one can determine the different twinning modes that have contributed to deformation but also the volume fraction of material that has twinned. This has enabled modellers to better understand the contribution of twinning in the hardening behaviour of the materials and to devise schemes to incorporate the effects of twinning on the hardening response and texture evolution of hcp metals. We present here a new twinning scheme that account for several twin variants been active at the same time within a grain. This model is used to predict the hardening response, texture and twin volume fraction evolution of pure zirconium deformed quasi-statically at 76K.
Keywords:
twinning, crystal plasticity, zirconium
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