Transactions of Materials and Heat Treatment

Title：Study of forming process for AZ31 magnesium alloy during multiple passes ECAP based on homogeneous deformation

Authors： ZHOU Chao PENG Bi-you SHEN Bing WANG Hong-bo

Unit： Xihua University

KeyWords： equal channel angular pressing AZ31 magnesium alloy homogeneous deformation grain refinement finite element simulation

ClassificationCode：TG376

year,vol(issue):pagenumber：2013,38(3):145-151

Abstract：

The effects of ECAP deformation process conditions on homogeneous deformation of AZ31 magnesium alloy were investigated through rigid plastic finite element method. The average effective strain of main deformation zone in sample obtained by simulation was consistent with the theoretical effective strain highly. The results show that the improvement of homogeneous deformation concentrates in the first 4 passes，and there is a little variation in the last 4 passes. The excessively high or low temperature of billet is not conducive to the homogeneous distribution of strain. An appropriate friction and low extrusion speed can promote sample to deform evenly. Combined with orthogonal experiment，the obtained optimal solution to control homogeneous deformation is mold temperature at 240 ℃, billet temperature at 270℃, coefficient of friction at 0.3, extrusion speed at 3 mm·s-1.

Funds：

四川省高校重点实验室（西华大学）开放研究基金资助项目（S2JJ2012-001）；四川省教育厅重点科研项目资助项目（11ZA001）

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