Zn-22Al合金ECAP变形行为及对显微组织的影响  

Deformation Behavior of ECAP and Influence on Microstructure in Zn-22Al Alloys

作　　者：曾许多 张阳明[1,2] 胡方勤[1,2] 郑必长[1,2] 宋振纶[1,2] 

机构地区：[1]中国科学院宁波材料技术与工程研究所,浙江宁波315201 [2]宁波市海洋防护与工程技术重点实验室,浙江宁波315201

出　　处：《热加工工艺》2013年第23期20-23,27,共5页Hot Working Technology

基　　金：国家科技支撑计划项目(2009BAE71B05);宁波市自然科学基金项目(2012A610057)

摘　　要：研究了挤压速率和温度对Zn-22wt%Al合金等通道挤压(ECAP)可加工性的影响及合金ECAP 1道次挤压变形行为和组织演变规律。实验结果表明,在合金ECAP挤压过程中,随加工温度下降和挤压速率提高形成锯齿形裂纹断口;随着温度的升高,合金由断裂向均匀流变转变,晶粒细化区域增大;合金在较低和较高速率下ECAP最佳挤压温度分别为75℃和125℃。有限元模拟结果表明,经1道次挤压变形后,合金应力应变分布不均匀,形成应力应变梯度,这与实验结果吻合。The influence of the extrusion rates and temperatures on the workability of Zn-22wt% A1 alloy pressed by equal-channel angular pressing （ECAP） was studied, and the evolution ofmicrostructure and deformation behavior of the alloy during the process of ECAP with one pass were investigated. The experimental results show that in ECAP extrusion process of alloy, serrated cracks were formed with the decrease of extrusion temperature and the increase of extrusion rates. As the processing temperature increases, the deformation of the alloy turns from fracture to uniform rheology, and the area of refined grains is increased.The optimal extrusion temperature of the alloy processed by ECAP at low extrusion rate is 75 ~C, and the optimal extrusion temperature at high extrusion rate is 125℃, respectively. The finite element simulation results show that the distributions of the strain and the stress of the alloy are nonuniform and a strain-stress gradient is formed, which is consistent with the experiment results.

关 键 词：等通道挤压 Zn-22Al合金 应力应变 数值模拟 

分 类 号：TG376.2[金属学及工艺—金属压力加工]