GH4169瞬时液相扩散连接界面及力学性能分析  

Interface and mechanical properties analysis of transient liquid phase diffusion bonding for GH4169

作　　者：杨琳琳 郎利辉[1] 李晓星[1] 梅寒 王文鹏 徐文才 Yang Linlin;Lang Lihui;Li Xiaoxing;Mei Han;Wang Wenpeng;Xu Wencai(School of Mechanical Engineering & Automation,Beihang University,Beijing 100191 ,China)

机构地区：[1]北京航空航天大学机械工程及自动化学院,北京100191

出　　处：《锻压技术》2019年第3期149-154,192,共7页Forging & Stamping Technology

基　　金：国家自然科学基金资助项目(51675029)

摘　　要：采用真空瞬时液相扩散连接技术(TLP-DB)对航空用高温合金GH4169进行了连接;在一定压强、温度及保温时间等主要工艺参数下,使用BNi2钎料作为中间层材料,实现GH4169的有效连接。用金相显微镜、扫描电镜、能谱分析仪和拉伸试验机等设备,对比相同条件下的直接扩散连接,分析TLP-DB的接头界面组织形貌、元素分布及连接强度等特点。结果表明:GH4169合金在压强20 MPa、温度1100℃、保温保压时长90 min的条件下,TLP-DB连接接头的室温抗拉强度(1006 MPa)接近母材室温抗拉强度,远高于同工艺条件下直接扩散连接强度;连接接头的拉伸断裂方式为脆性断裂,有少量韧窝的存在;经过塑性变形和元素扩散,接头界面的扩散层孔隙数目减少并产生了新的金属间化合物,孔隙和化合物的变化影响着接头的力学性能。The aviatic high-temperature alloy GH4169 was bonded by transient liquid phase diffusion bonding( TLP-DB),and an effective connection of GH4169 under a series of main process parameters such as pressure,temperature and holding time was achieved by BNi2 solder used as the inter layer material. Then,comparing with the direct diffusion connections under the same conditions,the characteristics of microstructure,element distribution and joint strength of the TLP-DB joint interface were analyzed by metallographic microscope,scanning electron microscope,energy spectrum analyzer and tensile testing machine. The results show that the tensile strength at room temperature( 1006 MPa) of the TLP-DB joint is close to that of the base metal under the conditions of pressure 20 MPa,temperature1100 ℃ and holding time 90 min,which is much higher than that of the direct diffusion bonding under the same process conditions. The tensile fracture mode of the joint is brittle fracture with a few dimples. Furthermore,after plastic deformation and element diffusion,the number of pores in the diffusion layer at the interface of the joint decreases and new intermetallic compounds are produced. The changes of pores and compounds affect the mechanical properties of the joint.

关 键 词：高温合金GH4169 瞬时液相扩散连接 连接强度 界面分析 力学性能 

分 类 号：TG389[金属学及工艺—金属压力加工]