TiAl合金与镍基高温合金的扩散连接

Diffusion bonding of TiAl to Ni-based superalloy

摘要: 采用钛为中间层,对TiAl合金与镍基高温合金(GH99)进了扩散连接.研究了扩散连接接头的界面结构和连接温度对界面结构及连接性能的影响,并对连接界面反应层的形成机制进行探讨.结果表明,GH99/Ti/TiAl的界面结构为:GH99/(Ni,Cr)_ss/富Ti-(Ni,Cr)_ss/TiNi/Ti₂Ni/α-Ti+Ti₂Ni/Ti(Al)_ss/TiAl+Ti₃Al/TiAl;随着连接温度的升高,各反应层厚度增加,接头的抗剪强度先增加后减小;在连接温度1173 K,连接时间30 min,连接压力20 MPa时,抗剪强度最高为260.7 MPa.

Abstract: Diffusion bonding of TiAl to Ni-based alloy using Ti interlayer was studied.The microstructure of the joint and effect of bonding temperature on microstructure and properties of the joint were investigated,and the mechanism of the formation of reaction layers was also discussed.The experiment results show that the interfacial structure of the GH99/Ti/TiAl joint is GH99/(Ni,Cr)_ss/rich Ti-(Ni,Cr)_ss/TiNi/Ti₂Ni/α-Ti+Ti₂Ni/Ti(Al)_ss/TiAl+Ti₃Al/TiAl.With the bonding temperature increasing,the thickness of reaction layers increases.The shear strength of the joint increases with the bonding temperature,and goes through a maximum at 1173 K/30 min/20 MPa and thereafter falls off.The maximum shear strength is 260.7 MPa.