镀银编织铜丝与铜层微电阻点焊接头组织与性能研究

研究了0.1 mm镀银编织铜丝与0.07mm厚度超薄纯铜层微电阻点焊接头的微观组织和力学性能,分析了不同参数对接头力学性能的影响,采用扫描电子显微镜对典型接头的微观组织结构特征进行了分析。结果表明,当焊接热量足够时,焊点接头主要为钎焊-熔焊混合连接机制,其形成过程中经历银元素润湿铺展、银元素扩散、铜元素熔化和金属凝固四个过程;焊点连接面处组织致密,存在铜银两相与单富铜相构成连接界面形态,后者焊点微观组织结构含有熔焊的特征;试验所用参数范围内,焊点的最大抗剪力可达45 N,焊接时间与焊接电流均在一定的范围内对焊点性能影响较大,当电阻产热达到饱和区间,焊点抗剪切性能变化不大。

Microstructures and mechanical properties of micro-resistance spot welded joint of silver-plated braided copper wire and copper

The microstructure and mechanical properties of 0.1 mm silver-plated braided copper wire and 0.07 mm copper micro-resistance spot welded joint were studied.The influences of different parameters on the mechanical properties of the joint were analyzed.The microscopic analysis of the typical joint was performed by scanning electron microscopy.The microstructure characteristics were analyzed.The results show that the joint is mainly formed by brazing-welding and fusion welding,and the four processes of silver element wetting and spreading,silver element diffusion,copper element melting and metal solidification are experienced in the formation process.There is a copper-silver two-phase and a single-rich copper phase formed in joint interface morphology,and the latter soldered joint microstructures have the characteristics of fusion welding.Within the parameters used in the tests,the maximum shear force of the soldered joint can reach 45 N.The welding time and the welding current have a great influence on the soldered joint performance within a certain range.When the resistance heat reaches the saturation interval,the shear resistance of the joint change little.