采用有限元软件Deform-3D对室温纯钛等径弯曲通道变形(ECAP)过程进行数值模拟,分析了不同等通道截面形状条件下载荷变化、变形行为以及等效应变分布情况。结果表明:不同截面形状试样随着通道截面圆角增大,端部效应有所增加,试样与出口通道上壁之间的缝隙增大;不同通道截面挤压的行程载荷曲线趋势一致,常用的方形截面(R=0 mm)ECAP挤压时载荷最大;ECAP挤压后,试样纵向上等效应变从中部向两端递减,竖直方向上等效应变从上到下逐渐下降;方形(R=0 mm)和圆形(R=10 mm)截面ECAP挤压的等效应变较高,特别是圆形截面ECAP挤压心部等效应变要高于外表,这有别于其他塑性变形形式。
The process of the equal channel angular pressing (ECAP) for pure titanium at room temperature was simulated by the finite element software Deform-3D. The load variety, deformation behavior and the effective strain distribution were analyzed with the different shapes of same channel section. The results show that the end effect of the different section shapes of specimen increases somewhat, and the gap between sample and the above wall of export channel enlarges with the increase of channel section fillet, however, the load-stroke curve tendencies are consistent for extrusion of different channel sections. The load of the common square section (R = 0 mm) by ECAP is the maximum ; the vertical effective strain declines from the middle to both ends and the lateral effective strain decreases gradually from top to bottom after ECAP; the effective strains of square (R =0 mm) and circular (R = 10 mm) section samples after ECAP become higher, especially the effective strain of core in circular section sample after ECAP is higher than that of appearance, which is different to other forms of plastic deformation.