锻压技术

基于变形均匀性的AZ31镁合金ECAP多道次成形工艺研究

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

作者：周超彭必友沈冰汪红波

单位：西华大学

分类号：TG376

出版年,卷(期):页码：2013,38(3):145-151

摘要：

以AZ31镁合金为研究对象，利用刚塑性有限元法，研究ECAP变形工艺条件对变形均匀性的影响。模拟得到的试样主要变形区的平均等效应变值与理论等效应变值吻合度高。结果表明：变形均匀性改善主要集中在前4道次，而后4道次变化不大；过高或低的坯料温度均不利于应变的均匀分布；适当的摩擦系数和较低的挤压速度能促进试样均匀变形。结合正交实验，得出控制变形均匀性的最优方案是：模具温度240℃，坯料温度270℃，摩擦系数0.3，挤压速度3mm·s-1。

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.

基金项目：

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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