摘要
采用50μm纯Ni箔+10μm纯Nb箔复合中间层,在焊接温度840℃,880℃和920℃,压力4MPa以及保温时间60min的工艺下,对工业纯钛TA2和1Cr18Ni9Ti不锈钢进行了真空扩散焊实验,测试了接头的抗拉强度,并利用光学显微镜(OM)、扫描电镜(SEM)、能谱(EDS)和X射线衍射(XRD)对接头的组织结构、元素分布以及断口形貌和相组成进行了分析。结果表明:Ni+Nb复合中间层的存在成功阻止了Fe,Ti互扩散,实现了TA2与1Cr18Ni9Ti的可靠连接,接头的拉伸强度达到261MPa,该强度主要受剩余Ni箔控制,且焊接温度的变化对其影响不大。接头所生成反应层自不锈钢一侧起分别为FeCrNi固溶体、剩余Ni,Ni3Nb,剩余Nb以及TiNb魏氏体。
Diffusion bonding in vacuum was carried out between commercially pure titanium TA2 and austenitic stainless steel 1Cr18Ni9Ti by using Ni＋Nb composite interlayer at the temperature of 840℃,880℃ and 920℃ for 60min under 4MPa axial pressure.The tensile strengths of the joints were tested,meanwhile the fracture surfaces were analyzed by SEM and XRD.The microstructure and element distribution of the joints were analyzed by OM,SEM and EDS.The results show that Ni＋Nb composite interlayer successfully suppresses interdiffusion of Ti and Fe,so that the sound joints were formed.Five reacted-layers are presented at the joint.They are FeCrNi solid solution,residual Ni,Ni3Nb,residual Nb,TiNb widmanstatten structure from 1Cr18Ni9Ti to TA2.The residual Ni is critical to strength of the joint,the strength reaches up to 261MPa and changes a less with temperature.
出处
《航空材料学报》
EI
CAS
CSCD
北大核心
2010年第5期25-29,共5页
Journal of Aeronautical Materials
