铬对改善铜与炭石墨材料润湿性的作用

采用座滴试样比接触面积法研究了Ｃｕ－Ｃｒ合金与柔性石墨和炭片的润湿性．Ｃｒ含量愈高，座滴与炭石墨材料的比接触面积愈大，接触角愈小．

Synergistic regulation of current-carrying wear performance of resin matrix carbon brush composites with tungsten copper composite powder

Resin matrix carbon brush composites(RMCBCs)are critical materials for high-powered electric tools.However,effectively improving their wear resistance and heat dissipation remains a challenge.RMCBCs prepared with flake graphite powders that were evenly loaded with tungsten copper composite powder(RMCBCs-W@Cu)exhibited a low wear rate of 1.63 mm^(3)/h,exhibiting 48.6%reduction in the wear rate relative to RCMBCs without additives(RMCBCs-0).In addition,RMCBCs-W@Cu achieved a low friction coefficient of 0.243 and low electric spark grade.These findings indicate that tungsten copper composite powders provide particle reinforcement and generate a gradation effect for the epoxy resin(i.e.,connecting phase)in RMCBCs,which weakens the wear of RMCBCs caused by fatigue under a cyclic current-carrying wear.

高速动车组受电弓滑板用炭条研制

在基体炭材料配方中添加一定比例的造孔剂、特殊耐磨添加剂,采用等静压成型、浸渍优化等措施,制得一种低电阻率高性能受电弓滑板用浸渍铜合金炭/铜复合材料。测试结果表明,受电弓滑板炭条材料抗折强度可达86~88 MPa,电阻率0.98~2.28μΩ·m,且水平与垂直方向电阻率接近,解决了现在普遍使用的挤压浸铜滑板水平与垂直方向电阻率相差近3倍的问题。此项制备技术有效、可行,有推广价值。