QBe2铍青铜与Cr20Ni80镍铬丝的微型件电容储能点焊

Capacitive Storage Spot Welding on Minisize Workpiece of QBe2 Beryllium Bronze and Cr20Ni80 Nicochrome Wire

阐述了在微型电机电刷零部件的生产过程中,铍青铜与镍铬丝电容储能点焊的工艺过程,分析了微型件点焊的特殊性,计算了微型件的热时间常数τ,且根据选择的规范参数及焊接电流波形,提出了τ及电流上升时间之间的一些对应关系,并对焊接接头的金相组织,元素扩散以及力学性能进行了分析试验。发现采用电容储能点焊机对QBe2铍青铜与Cr20Ni80镍铬丝微型件进行焊接可以获得良好的焊接接头,焊接界面铍青铜一侧有晶界局部熔化现象,焊点的抗拉强度为375MPa,镍铬合金中的镍元素与铬元素有向铍青铜中扩散的现象。

The technological process about capacitive storage spot welding on minisize workpiece of beryllium bronze and nicochrome wire was expounded, which was used for electrical brush spare parts production process for micro-motor. The characteristic of the spot welding on minisize workpiece was analyzed and the thermal time constant T of minisize workpiece was calculated. Some corresponding relation between τ and current rising time were pointed out by specific parameter and current waveform. The metaUographic structure,element diffusion and mechanical property of welding joint were analyzed and tested. Nice welding joint can be acquired in minisize workpiece production process of beryllium bronze and nicochrome wire by using capacitive storage spot welding machine. There is grain boundary partial melting on the side of beryllium bronze. The tensile strength of the welding joint is 375 MPa. Nickel and chromium in Ni-Cr alloys diffuse into beryllium bronze.