新型大塑性变形复合挤扭过程数值模拟分析

针对挤扭（Twist Extrusion，TE）过程试样变形不均匀，结合挤扭和挤压工艺提出了复合挤扭（Composite Twist Extrusion，CTE）新型大塑性变形工艺。运用有限元分析法对纯铝在室温下进行数值模拟，获得了应力应变分布，载荷行程曲线，并对工艺进行改进消除了头部难变形区域。结果表明复合挤扭工艺可以有效地降低均匀系数，改进后的工艺可以获得变形均匀的试样。

Simulation Research on a New Severe Plastic Deformation Process Named as Composite Twist Extrusion

This paper introduces a new severe plastic deformation（SPD） process named as CTE process which combines the Twist Extrusion with Extrusion against the asymmetric deformation of TE process. Pure aluminum was used to investigate the deformation of CTE process via finite element method. The amount and distribution of effective stain, stress and load- stroke curve through the process of TE were obtained. The process was improved to avoid the stagnant zone. The results re veal that CTE process can significantly reduce the coefficient of uniformity. A sample of homogeneous deformation can be obtained by the improved process.