冲头形状ECAP模拟分析研究

ECAP simulation and analysis research of the punchshape

等通道角挤压(ECAP)是剧烈塑性变形制备超细晶材料的一种有效变形方式,常规的ECAP工艺获得组织不够均匀,损伤较大,由此提出了一种新型的ECAP冲头形状的改良研究。本文采用DEFORM-3D有限元模拟分析ECAP工艺变形机理的方案,引入几何参数λ,即理论剪切面与冲头和坯料的交界面之间的顺时针夹角,研究发现相比传统的水平冲头(λ=45°),采用λ=90°形状冲头可提高经一次通道ECAP挤压后坯料的均匀性,采用λ=0°的冲头的ECAP形变平均损伤显著减小。本研究可为ECAP的工艺研究提供理论指导。

The DEFORM-3Dfinite element has been adopted to simulate and analyze the proposal ot the process deformation mechanism for ECAP in the text. Anew geometric para meter λ （the clockwise angle be- tween theoretical shearing surface and the interface of punch and billet） has been introduced. By Comparing with conventional horizontal punch （λ=45°）, the uniformity of billet after extrusion by one-time ECAP than-nel has been improved by adopting the beveled punch （λ=90°）. Whilethe average damage has been signifi- cantly reduced by adopting the beveled punch （λ=0°）. It will provide theoretical guidance for process re- search of ECAP .