等通道转角挤压变形超细晶纯铜的组织与性能  

Microstructure and Properties of Ultrafine-Grained Pure Copper Based on Equal Channel Angular Pressing Deformation

作　　者：唐环 王晓溪[1] 张翔 佟鑫龙 张飞 崔海涛 TANG Huan;WANG Xiaoxi;ZHANG Xiang;TONG Xinlong;ZHANG Fei;CUI Haitao(School of Mechanical&Electrical Engineering,Xuzhou Univercity of Technology,Xuzhou 221000,China;Jiangsu XCMG Construction Machinery Research Institute Co.,Ltd.,Xuzhou 221004,China)

机构地区：[1]徐州工程学院机电工程学院,徐州221000 [2]江苏徐工工程机械研究院有限公司,徐州221004

出　　处：《机械工程材料》2024年第11期76-81,共6页Materials For Mechanical Engineering

基　　金：江苏省自然科学基金资助项目(BK20201150,BK20221212);江苏省高校自然科学研究重大项目(21KJA460007);江苏省“333高层次人才工程”培养资助项目;江苏省大学生创新创业计划训练项目(202311998006Z)。

摘　　要：在室温下采用BC路径(每道次挤压时将试样绕其轴线沿同一方向旋转90°)对T2纯铜进行4道次等通道转角挤压(ECAP),研究了不同道次ECAP变形前后纯铜的显微组织、力学性能和耐腐蚀性能。结果表明:经过1道次ECAP变形后,纯铜内部形成粗大的条带状组织,与剪切应力方向呈30°~45°;经过4道次ECAP变形后,纯铜晶粒发生显著破碎与细化,出现了大量的超细等轴晶组织,平均晶粒尺寸约为0.96μm;4道次ECAP变形后纯铜的显微硬度与抗拉强度较未变形显著提高,增幅分别为43.8%和51.5%;随着ECAP道次的增加,纯铜的溶液电阻、电荷转移电阻和极化电阻均增大,开路电位和自腐蚀电位均升高,自腐蚀电流密度减小,耐腐蚀性能提升。Four-pass equal channel angular pressing(ECAP)was performed on T2 pure copper by using the BC pathway(the specimen was rotated 90°in the same direction around its axis at each ECAP)at room temperature,the microstructure,mechanical properties and corrosion resistance of the pure copper before and after ECAP deformation for different passes(one-pass,four-pass)were studied.The results show that after one-pass ECAP deformation,a large banded structure was formed in the pure copper,and the direction of the band was at 30°‒45°to the direction of shear stresses.After four-pass ECAP deformation,the pure copper grains were broken and refined significantly,a large number of ultrafine-equiaxed grained structures appeared,and the average grain size was about 0.96μm.The microhardness and tensile strength of the pure copper after four-pass ECAP deformation significantly increased by 43.8%and 51.5%,respectively.With the increase of ECAP pass,the solution resistance,charge transfer resistance and polarization resistance of the pure copper increased,the open circuit potential and self-corrosion potential increased,and the self-corrosion current density decreased,indicating the corrosion resistance was improved.

关 键 词：ECAP变形 交变剪切应力 超细晶纯铜 力学性能 耐腐蚀性能 

分 类 号：TG376[金属学及工艺—金属压力加工]