使用有限元方法模拟在等径通道挤压过程中,后压力对材料塑性变形的影响,并对多道次挤压试验结果进行分析比较。结果表明:施加后压力可以有效提高材料每道次挤压的塑性变形程度和分布均匀性。在多道次挤压过程中,施加后压力可以大幅度降低晶粒最终细化尺寸,降低挤压温度来减小温度对晶粒细化效果的影响。
The effect of the backpressure on the plastic deformation of the billet material was investigated by finite element simulation in the equal channel angular pressing/extrusion(ECAP) process.The multiple-pass ECAP experiment results were also analyzed.The results show that the degree and uniformity of plastic deformation can be effectively enhanced by backpressure application during ECAP for every pass.In the multiple-pass ECAP experiment,there is a decrease in the equilibrium grain size and the processing temperature in the ECAP process with backpressure.