Ti69NbCrZrX中间层脉冲电流促进扩散焊TiAl/Ti_(2)AlNb接头的组织与性能  

Microstructure and properties of pulse current promoted diffusion welding TiAl/Ti_(2)AlNb joint with Ti69NbCrZrX interlayer

作　　者：吕彦龙 范佳锋 候金保 柴禄 陶军 LYU Yanlong;FAN Jiafeng;HOU Jinbao;CHAI Lu;TAO Jun(Aeronautical Key Laboratory for Welding and Joining Technologies,AVIC Manufacturing Technology Institute,Beijing 100024,China;National Engineering Research Center of Near-Net-Shape Forming for Metallic Materials,South China University of Technology,Guangzhou 510640,China)

机构地区：[1]中国航空制造技术研究院航空焊接与连接技术航空科技重点实验室,北京100024 [2]华南理工大学国家金属材料近净成形工程技术研究中心,广州510640

出　　处：《材料工程》2024年第12期143-150,共8页Journal of Materials Engineering

摘　　要：以新型Ti69NbCrZr X(X=Sn,W,Al,Mo,1%~2%,质量分数)为中间层,采用脉冲电流促进扩散焊在900℃/30min/8 MPa参数下连接TiAl合金与Ti_(2)AlNb合金。通过SEM,EDS,EBSD和室温拉伸技术分析焊后接头显微组织和性能。结果表明:以Ti69NbCrZr X为中间层可获得无缺陷TiAl/Ti_(2)AlNb接头。接头界面组织主要分为TiAl扩散影响区、中间层扩散区和Ti_(2)AlNb扩散影响区。TiAl扩散影响区组织由白色β相和灰色块状α_(2)相组成,中间层扩散区组织主要由灰色块状的α_(2)+α相和白色的β/B2相组成,Ti_(2)AlNb扩散影响区组织由β/B2基体相和分布在其中的板条状和针状O相组成。接头室温拉伸强度均值为642.5 MPa,达到母材强度的91.57%。接头断裂以沿晶脆性断裂为主,穿晶脆性断裂为辅。The novel Ti69NbCrZrX(X=Sn,W,Al,Mo,1%-2%,mass fraction)was used as an interlayer to join TiAl alloy with Ti_(2)AlNb alloy by pulsed current diffusion welding at 900℃/30 min/8 MPa.The post-weld joint microstructure and properties were analyzed by SEM,EDS,EBSD,and room temperature tensile test.The results show that defect-free TiAl/Ti_(2)AlNb joints can be obtained using Ti69NbCrZrX as the connecting interlayer.The joint interface microstructure is mainly composed of TiAl diffusion affected zone,interlayer diffusion zone,and Ti_(2)AlNb diffusion affected zone.The TiAl diffusion affected zone structure is composed of whiteβphase and gray blockα_(2)phase,the interlayer diffusion zone structure is mainly composed of gray blockα_(2)+αphase,and whiteβ/B2 phase composition,Ti_(2)AlNb diffusion affected zone is composed ofβ/B2 matrix phase with lath and acicular O phase.The average value of room temperature tensile strength of the joint is 642.5 MPa,which reaches 91.57%of the strength of the base material.The fracture mode of the joints is dominated by brittle intergranular fracture,supplemented by brittle transgranular fracture.

关 键 词：TIAL Ti_(2)AlNb 脉冲电流促进扩散焊 中间层 

分 类 号：TG453[金属学及工艺—焊接] TB31[一般工业技术—材料科学与工程]