镍基单晶高温合金瞬态液相连接接头的微观结构和结晶学取向  

MICROSTRUCTURE CHARACTERISTICS AND CRYSTALLOGRAPHIC ORIENTATION OF TRANSIENT LIQUID PHASE JOINT OF Ni-BASED SINGLE CRYSTAL SUPERALLOY

作　　者：李文[1,2] 金涛[2] 胡壮麒[2] 

机构地区：[1]沈阳理工大学材料科学与工程学院,沈阳110168 [2]中国科学院金属研究所,沈阳110016

出　　处：《金属学报》2008年第12期1474-1478,共5页Acta Metallurgica Sinica

基　　金：国家自然科学基金资助项目50474058~~

摘　　要：采用Ni-15Cr-3.5B非晶合金箔带作为中间层合金对镍基单晶高温合金进行瞬态液相(TLP)连接.利用光学显微镜、扫描电镜、透射电镜对接头的微观结构进行观察和分析,利用电子背散射衍射(EBSD)方法测定了连接区域和基体之间的结晶学取向,结果表明,接头区域由连接区、中间金属/基体金属界面扩散区和基体金属区组成,连接区中心形成M_(23)B_6+γ和MB+γ共晶,扩散区形成细小的M_3B_2颗粒;均匀化处理后接头与基体的γ′相的尺寸趋于一致;TLP接头等温凝固过程中,固/液界面向液相移动中外延生长,连接层与所连接的基体金属的结晶学取向一致.The Ni based single crystal superalloy was bonded by the transient liquid phase （TLP） bonding using Ni-15Cr-3.5B amorphous ribbon as an insert alloy. The microstructure characteristics in the joint during TLP process were evaluated by OM, SEM and TEM. The electron back scattering diffraction （EBSD） method was applied to determine the crystallographic orientation between the bonded interlayer and substrates. The results indicated that the joint consists of a bond, diffusion and base zones, in the meantime M23B6 ＋γ and MB＋γ eutectics formed in the bond center and the fine M3B2 phases occurred in the diffusion zone. The γ＇ phases both in the bonded interlayer and in the superalloy substrate are almost identical after homogenization treatment. Due to the epitaxial growth of the isothermal solidification fronts from each mating surface, the crystallographic orientation between the bonded interlayer and the bonded substrate has a good match.

关 键 词：镍基单晶高温合金 TLP连接 微观结构 结晶学取向 

分 类 号：TG425[金属学及工艺—焊接] TG113