中文摘要：

运用有限元模拟软件MSC.Marc对纯铜挤扭工艺进行研究,分析挤扭变形过程、应变分布以及挤压道次对应变分布的影响。结果显示,变形可分为变形开始、完全充满、逐步挤出3个阶段。1道次成形后试样中心应变量较小,边缘处相对较大;随着挤压道次的增加,试样中心、边缘应变量均显著增大。采用自行设计的挤扭模具,在室温下进行纯铜的多道次挤扭试验。试验结果表明,应变量较大的边缘处晶粒变形较为剧烈,硬度值也相对较高;挤压道次增加,应变量增大,晶粒变形剧烈,硬度值愈高。

英文摘要：

The finite element simulation on pure copper deformation during twist extrusion（TE）was carried out by simulation software MSC.Marc.The procedure steps of TE,the distribution of effective strain and the change of strain component were analyzed.The results show that TE deformation could be divided into three steps.After one TE pass,the value of the effective strain in the edge area would be much larger than the center area.After more TE passes,the value of effective strain of both center area and edge area increase significantly.The experiment on pure copper at room temperature during TE was carried out using self-designed die.The results show that the crystals suffered greater deformation and the microhardness getting higher in the area where effective strain is larger.After more TE passes,the value of effective strain became larger,the crystals suffered greater deformation,and the microhardness increase s significantly.