CuFeW触头材料的性能

为了提高CuW的物理机械性能,使其具有更好的耐电弧烧蚀性能和更长的使用寿命,笔者采用熔渗法制备了添加不同体积分数Fe元素的CuFeW合金,研究了Fe元素的添加对CuW合金的组织、硬度、电导率、电击穿性能的影响。结果表明,CuFe合金中Fe的加入量小于1.5%时,熔渗后的CuFeW合金的硬度随Fe体积分数的增加略有增加,而电导率则随之减小,固溶时效处理后合金的电导率有所提高。Fe元素的添加提高了CuW合金的耐电压强度,降低了材料的截流值。对真空电击穿后的材料表面电烧蚀形貌观察发现,电弧在CuFeW合金表面分布较为分散,Fe的加入使首次击穿由原来集中连续地发生Cu/W相界面上转移到非连续地选择性在Cu基体上击穿,产生的击穿坑较小且分散,铜液的飞溅现象减少。

Properties of CuFeW Electrical Contact Materials

A series of CuFeW alloys added with different Fe contents were prepared by the infiltration method.The effects of Fe addition on the microstructure,hardness,electrical conductivity and electrical breakdown characteristics of Cu-W alloy were investigated.The results show that the hardness of CuFeW alloys increases with increasing Fe contents,while the electrical conductivity decreases with increasing Fe percentage from 0% to 1.5% in the Cu-Fe alloys.The electrical conductivity of CuFeW alloys increases significantly after solid solution and aging treatments.The breakdown voltage of Cu-W alloys increases and the chopping current of the alloys decreases with Fe addition.The surface morphologies of CuFeW and Cu-W alloys after electrical breakdown show that vacuum arcs are scattered slightly on the surface of CuFeW alloys,the first electrical breakdown occurs discontinuously and selectively in copper matrix phase rather than occurs continuously and concentratively in the interphases of Cu/W owing to the addition of Fe element into Cu-W alloy,the formed cathode spots are small and disperse,and the splash of liquid copper is slight.