C18000铜合金搅拌摩擦焊接头微观组织与性能  

Microstructures and properties of friction stir welds of C18000 copper alloy

作　　者：贺地求 马力[1] 孙友庆 赖瑞林 HE Diqiu;MA Li;SUN Youqing;LAI Ruilin(Light Alloy Research Institute,Central South University, Changsha 410083, China;State Key Laboratory of High Performance Complex Manufacturing,Central South University, Changsha 410083, China)

机构地区：[1]中南大学轻合金研究院,长沙410083 [2]中南大学高性能复杂制造国家重点试验室,长沙410083

出　　处：《焊接学报》2019年第4期55-60,I0003,共7页Transactions of The China Welding Institution

基　　金：国家重点基础研究发展计划(973计划)(2014CB046605);中南大学研究生科研创新项目(1053320170397)

摘　　要：对3.5 mm厚的C18000铜合金板进行搅拌摩擦焊焊接试验.在焊接速度120 mm/min,转速1 200 r/min工艺下获得无缺陷焊接接头.在金相显微镜下对接头的宏观形貌、微观组织进行观察,用扫描电镜和透射电镜对母材和搅拌区组织进行观察分析.结果表明,接头区大致分为母材区、热影响区、热力影响区和搅拌区,搅拌区晶粒细小均匀,热力影响区晶粒沿边界切线方向被拉长;搅拌区Cr3Si相部分溶解,搅拌区组织中的Cr单质相和Ni2Si相溶解导致接头硬度和抗拉强度下降.搅拌区平均硬度为151.4 HV;接头抗拉强度为497 MPa,达到母材的72%;接头电导率下降为35%IACS.C18000 copper alloy plate with thickness of 3.5 mm was subjected to friction stir welding experiment.Sound welded joints were obtained under the welding speed of 120 mm/min and the rotation speed of 1 200 r/min. The macromorphology and micro-structure of the joint were observed under metallographic microscope, and the microstructure of the base metal and stirring zone were observed and analyzed by scanning electron microscopy and transmission electron microscopy. The results showed that the joint zone could be generally divided into the base metal (BM), the heat affected zone (HAZ), the thermo-mechanically affected zone (TMAZ) and the stir zone (SZ). The grain in SZ was small and welldistributed, and the grain in TMAZ was elongated along the tangential direction of the boundary. It was found that the particles were Cr3Si phase, and it was dissolved in the stirring zone. The Cr element phase and Ni2Si phase dissolved in the microstructure of SZ, which resulted in a decrease in joint hardness and tensile strength. The average hardness of the SZ was 151. 4 HV;the tensile strength of the joint was 497 MPa, which was 72% of the BM. The conductivity of the joint dropped to 35% IACS.

关 键 词：C18000铜合金 微观组织 透射电镜 力学性能 电导率 

分 类 号：TG453.9[金属学及工艺—焊接]