Polycrystalline Behavior Analysis of Extruded Magnesium Alloy AZ31

doi:10.1007/s12204-012-1295-8

Abstract

Abstract: Uniaxial tensile and compressive tests were performed at room temperature on extruded AZ31 Mg alloy specimens and distinct tensile-compressive anisotropy was detected. Deformed specimens were examined and the results indicate that the generation of {10ˉ12}twin is responsible for the mechanical anisotropy. A rate independent crystal plasticity model, which accounts for both slip and twinning, was developed for polycrystalline hexagonal close packed (HCP) materials. Model predictions for the stress-strain curves and texture evolution were in reasonable agreement with the experimental results. Specifically, the model captured the three stages of strain hardening for uniaxial-compression. By comparing stress-strain curves and texture evolution between model predictions and experimental measures, information about the dominant slip and twinning systems active at room temperature was deduced.

Key words: mechanical properties| microstructure| texture| crystal plasticity| twinning

摘要： Uniaxial tensile and compressive tests were performed at room temperature on extruded AZ31 Mg alloy specimens and distinct tensile-compressive anisotropy was detected. Deformed specimens were examined and the results indicate that the generation of {10ˉ12}twin is responsible for the mechanical anisotropy. A rate independent crystal plasticity model, which accounts for both slip and twinning, was developed for polycrystalline hexagonal close packed (HCP) materials. Model predictions for the stress-strain curves and texture evolution were in reasonable agreement with the experimental results. Specifically, the model captured the three stages of strain hardening for uniaxial-compression. By comparing stress-strain curves and texture evolution between model predictions and experimental measures, information about the dominant slip and twinning systems active at room temperature was deduced.

关键词: mechanical properties| microstructure| texture| crystal plasticity| twinning

CLC Number:

TG 146.2

TANG Wei-qin (唐伟琴), HUANG Shi-yao (黄诗尧), ZHANG Shao-rui (张少睿), LI Da-yong (李大永), PENG Ying-hong* (彭颖红). Polycrystalline Behavior Analysis of Extruded Magnesium Alloy AZ31[J]. Journal of shanghai Jiaotong University (Science), 2013, 18(2): 186-189.

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