![]() The basal, prismatic and pyramidal slip systems in the parent grain, compressive twinning (CT) and tensile twinning (TT) are incorporated in the model. The observed plastic deformation mechanisms of slip, twinning and their interaction are accounted for. At the intergranular scale, it is concluded from the slip-dominated case that a high slip-transfer parameter and high Schmid factors (SFs) of principal slip systems in adjacent grains could accommodate higher local strain.Ī rate-dependent elastic-viscoplastic constitutive model is proposed to simulate the plane strain deformation of pure magnesium crystal. At the mesoscale, the heterogeneity in the slip-dominated cases tends to develop continuously, whereas the heterogeneity is retarded in twin-favored deformation. Furthermore, deformation heterogeneity at the mesoscopic and intergranular scale were investigated based on the proposed model. Predicted average stress-strain responses and texture evolution are in good accordance with measured ones. Corresponding experimental investigations, including mechanical tests, electron back scattered diffraction (EBSD) measurements and optical observation, were also carried out as either a validation or a supplement of the numerical results. The optimal process parameters of the as-cast Mg–Zn–Ca–Sr alloy involved deformation temperatures of 603–633 K and strain rates of 0.03–0.005 s–1.Ī phenomenological crystal plasticity finite element (CPFE) model based on Voronoi grains was applied to reproduce basic deformation features of a hot-extruded magnesium alloy sheet under various strain paths. After compression, the alloy had a strong basal texture, and its textural strength decreased at first and then increased slightly as the deformation temperature rose. Dynamically recrystallized grains predominantly nucleated near the grain boundary and the secondary phases. With an increase in temperature, both the grain size and the degree of dynamic recrystallization increased. The mean apparent activation energy of the hot compression deformation of the Mg–3wt%Zn–1wt%Ca–0.5wt%Sr alloy was 250.44 kJ/mol. In this study, the microstructure, deformation behavior, textural evolution, and processing map of an Mg–3wt%Zn–1wt%Ca–0.5wt%Sr alloy were studied via a compression test using a Gleeble 1500D thermo-mechanical simulator. The Mg–Zn–Ca–Sr alloy has good application prospects as a bone implant material however, the as-cast alloy has both poor plasticity and formability, and there are few studies on its deformation properties. The effort on the study of magnesium single crystal in the present work contributes to further polycrystalline analysis. Basal slip is found to be easily activated due to a slight deviation, while a slight deviation in the twin-favored case could result in a significant difference in the mechanical behavior after the reorientation. ![]() Furthermore, the effect of an initial deviation angle on the mechanical responses was evaluated, which is proved to be also orientation-dependent. It is also found in the simulation that basal slip in the twinned region is active even before the saturation of twin activity in a twin-favored case. The predicted macro-and microscopic responses, along with the experimental results, show strong orientation-dependent properties. Related material parameters were calibrated at first according to the classical channel-die tests. The proposed model was then applied to the simulation of plane-strain compression deformation for different orientations. Twin-induced lattice reorientation was also incorporated in the model. Four deformation mechanisms (including basal 〈a〉, prismatic 〈a〉, pyramidal 〈c + a〉 slip and tension twin) and their interactions were considered. A phenomenological crystal plasticity constitutive model for magnesium single crystal was presented.
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