Analysis of the Microstructure of the Melted Layer of CuCr Contact After arc Action

CuCr45 was prepared by vacuum consumable arc melting and CuCr50 alloy material was prepared by vacuum infiltration method. The ablation of CuCr45 contacts and the microstructure and composition changes of the melted layer under arc action were studied and analyzed after 30 successful disconnections of CuCr45 contacts at 12KV/4000A-40KA and CuCr50 contacts at 72.5KV/3150A-40KA.Research has shown that the surface melting layer thickness of CuCr45 and CuCr50 alloys after arc action is between 20-60 μ m, composed of the majority of spherical Cr particles smaller than 1 μ m uniformly dispersed on the Cu phase. The microstructure of the melting layer shows significant refinement, and the surface is relatively flat after the arc action, without obvious dispersed erosion pits.