软导体用无氧铜带材的扩散焊工艺和接头性能

Diffusion Welding Technology and Welding Joint Properties of Oxygen-Free Copper Strip Used for Flexible Conductor

针对无氧铜软导体的连接问题,采用无中间层和预置中间层(镀银无氧铜带材和钎料BAg45CuZn)的焊接工艺,在真空热压烧结炉中于740～940℃对多层无氧铜带材进行真空热压扩散焊试验,并通过拉剪力、电导率、硬度测试和组织与微区成分分析对焊接接头进行研究。结果表明:随着扩散焊温度升高和保温时间延长,无中间层无氧铜带材扩散焊接头的拉剪力增大;表面硬度随扩散焊温度的升高而下降,电导率随扩散焊温度的上升而略有提高;预置钎料中间层焊接接头的拉剪力最高,其结合界面间的连接属于钎焊连接。

In view of the problem in bonding oxygen-free copper strip flexible conductor, diffusion welding experiments for oxygen-free copper strips were carried out with silver coated oxygen-free copper and BAg45CuZn filler metal as interlayer and no interlayer at a temperature of 740-940℃ in the vacuum hot-pressing sinter. The welding joints were studied through test of tensile shear force, electrical conductivity and hardness, scanning electron microscopy （SEM） and energy dispersive spectroscopy （EDS）. The results show that the tensile shear force of the joint without interlayer was increased with the increase of the diffusion welding temperature and holding time. When diffusion welding temperature rose, surface hardness of the joint without interlayer decreased, but conductivity increased slightly. The strongest tensile shear force was given by the joint of oxygen-free copper strip with filler metal as interlayer, and its bonding interface belonged to brazed connection.