Interface characteristic and mechanical performance of TiAl/Ti_(2)AlNb diffusion bonding joint with pure Ti interlayer  

作　　者：Lei Zhu Bin Tang Ming-Xuan Ding Yan Liu Xiao-Fei Chen Shao-Peng Yan Jin-Shan Li 

机构地区：[1]State Key Laboratory of Solidification Processing,Northwestern Polytechnical University,Xi'an 710072,China [2]Shaanxi Key Laboratory of High-Performance Precision Forming Technology and Equipment,Northwestern Polytechnical University,Xi'an 710072,China

出　　处：《Rare Metals》2020年第12期1402-1412,共11页稀有金属（英文版）

基　　金：the National Natural Science Foundation of China(No.51771150);the National Key Research and Development Program of China(No.2016YFB0701303);the Aeronautical Science Foundation of China(No.201936053001);the Research Fund of the State Key Laboratory of Solidification(NWPU),China(No.2019-TS-07)。

摘　　要：Solid-state diffusion bonding(DB)of TiAl alloy and Ti2 AlNb alloy was carried out using pure Ti as an interlayer at 1000℃under 20 MPa for 60-120 min.The effects of bonding times on the interfacial microstructure and mechanical performance of the TiAl/Ti/Ti_(2)AlNb bonded joints at room temperature(RT)were investigated detailly.The results demonstrated that the diffusion layers(DLs)mainly consisted of four characteristic layers,(Ⅰ)single coarseα_(2)phase adjacent TiAl alloy,(Ⅱ)single refinedα_(2)phase at the bonding interface,(Ⅲ)equiaxed/acicularα_(2)phase embedded inβphase adjacent Ti_(2)AtNb alloy and(IV)both equiaxedα_(2)phase and acicular O phase embedded inβphase adj acent Ti_(2)AlNb alloy,respectively.The thickness of the four layers increased with the increasing of the bonding time.The growth of DLs is controlled by diffusion and the reaction rate constant k for regionⅠ,Ⅱ,ⅢandⅣare 1.22×10^(-6),1.27×10^(-6),2.6×10^(-7)and 7.7×10^(-7)m·s^(-1/2),respectively.Meanwhile,the interfaceα_(2)grain grows up without texture.The maximum tensile strength of 281 MPa was maintained at1000℃for 90 min under the pressure of 20 MPa.Consequently,the phase transformation and dynamic recrystallization behavior of the DLs were discussed.

关 键 词：SPUTTERING Bonding interface MICROSTRUCTURE Growth kinetics Mechanical performance 

分 类 号：TG453.9[金属学及工艺—焊接]