TiNi形状记忆合金电阻钎焊接头微观组织分析

Analysis on micro structure of resistance-brazed joint of TiNi shape memory alloy

摘要: 利用自行改制的数控交流电阻焊机,采用CuNi薄带钎料,配合改进型钎剂实现了TiNi形状记忆合金电阻钎焊连接。借助于光学显微镜、SEM及EDX对钎缝的组织进行了分析。结果表明,试验采用的电阻钎焊工艺对母材的热影响极小,接头中没有明显的热影响区;在钎缝中存在的Ti₃Ni₄化合物相是TiNi合金产生双程及全程形状记忆效应的主要因素。

Abstract: Resistance brazing TiNi shape memory alloy wire with the self-improved numerical control alternating current resistance welding machine and CuNi filler foil matching the improved flux is realized.Micro-structures of resistance-brazed joint are analyzed using Optical Micro-scope,SEM and EDX measures.The results show that resistance brazing technology has less effect on the microstructure of base metal,and the joint has no obvious heat-affected zone.Ti₃Ni₄ phase compound,which is the key factor of producing double round and all round shape memory effect of TiNi shape memory alloy,is found in the joint.