ECAP变形不均匀性有限元分析及优化设计

Finite Element Analysis and Optimization Design of ECAP Deformation Heterogeneity

通过对等径弯曲通道变形(ECAP)过程的数值模拟,分析了挤压过程中等效应变不均匀性现象,获得了ECAP变形的等效应变分布规律,提出了解决变形不均匀性的思路,并进行了挤压模具的改进。结果表明:模具通道内设置阻尼台阶能使试样下部的等效应变由改进前的0.965提高为1.919,变形程度得到明显改善,等效应变不均匀程度参数降低0.123,降幅达到23.7%。

The phenomenon of the effective strain heterogeneity in extrusion process was analyzed through the numerical simulation of equal channel angular pressing （ECAP）. The effective strain distribution of ECAP was obtained. The idea of solving the deformation heterogeneity was proposed. And the improvement of extrusion die was carried out. The results show that arranging damping step in the die passage can increase the effective strain of the lower part of the specimen from 0.965 before improvement to 1.919, the degree of deformation is improved obviously, and the heterogeneity parameters of effective strain decrease by 0.123, decreasing amplitude reached by 23.7%.