To solve critical issues of premature failure for copper tungsten (CuW) based electrical contacts during arc erosion at the moment of arc breakdown, we proposed a new strategy of using metal doped reduced graphene oxides (rGOs) and in-situ formed tungsten carbides to inhibit movements of cathode spots during the arc ablation process. CuW composites were reinforced with Cu modified rGO nanopowders (i.e. Cu@rGO) using combined processes of chemical co-reduction, ball milling and spark plasms sintering (SPS). Effects of Cu@rGO addition on microstructure, arc erosion resistance and arc ablation resistance of the CuW composites were systematically investigated. Results showed that tungsten carbides with irregular shapes were formed through in-situ reactions of rGO and tungsten during the SPS process. Arc erosion resistance of CuW composites was significantly improved owing to introduction of nanostructured Cu@rGO. Compared with those of CuW composites, the ablation areas of Cu@rGO/CuW ones were much smaller and the ablation craters were shallower, and the average strengths of dielectric vacuum breakdowns of the CuW composites with 3 wt% Cu@rGO were increased by 28.9%. The arc breakdown mechanisms of Cu@rGO/CuW composites were identified as: (1) The nanostructured Cu@rGO increases the viscosity of molten metal Cu, thus inhibiting its fast flow and splashing; (2) Lower work functions of carbon (i.e. rGO) and tungsten carbide restrain the electron emissions during arc breakdown; and (3) The tungsten carbides with their good stability and high melting point shorten the solidification time of molten copper liquid and extend the service life time of the Cu@rGO/CuW composites.

为了解决在电弧击穿瞬间电弧侵蚀期间基于铜钨 (CuW) 的电触点过早失效的关键问题，我们提出了一种使用金属掺杂的还原氧化石墨烯 (rGO) 和原位形成的碳化钨来抑制电弧烧蚀过程中阴极点的移动。使用化学共还原、球磨和火花等离子体烧结 (SPS) 的组合工艺，用 Cu 改性的 rGO 纳米粉末（即Cu@rGO）增强 CuW 复合材料。系统研究了添加Cu@rGO对CuW复合材料微观结构、耐电弧侵蚀性和耐电弧烧蚀性能的影响。结果表明，原位形成了形状不规则的碳化钨。SPS过程中rGO和钨的反应。由于引入了纳米结构的 Cu@rGO，CuW 复合材料的抗电弧侵蚀性显着提高。与CuW复合材料相比，Cu@rGO/CuW复合材料的烧蚀面积更小，烧蚀坑更浅，3 wt% Cu@rGO的CuW复合材料的介电真空击穿平均强度提高了28.9 %。Cu@rGO/CuW复合材料的电弧击穿机理确定为：（1）纳米结构的Cu@rGO增加了熔融金属Cu的粘度，从而抑制了其快速流动和飞溅；(2) 碳的低功函数（即rGO）和碳化钨抑制电弧击穿期间的电子发射；(3)碳化钨具有良好的稳定性和高熔点，缩​​短了熔融铜液的凝固时间，延长了Cu@rGO/CuW复合材料的使用寿命。