原位合成Cr2Nb/CuCr复合材料及其真空电特性

采用真空烧结熔渗法制备不同Cr2Nb含量的Cr2Nb/CuCr复合材料.通过XRD和SEM研究复合材料的组织结构,采用SEM和高速摄影研究原位合成的Cr2Nb对复合材料表面电弧运动及表面烧蚀形貌的影响.结果表明:随着Cr-Nb复合粉末添加量的增加,Cr2Nb/CuCr复合材料的硬度、电导率、截流值、电弧寿命和耐电压强度均有明显改善,当Cr-Nb复合粉末的添加量为7％(质量分数)时,Cr2Nb/CuCr复合材料的阴极斑点更为分散,截流值显著降低,电弧寿命明显延长.与常规CuCr合金性能相比,Cr2Nb/CuCr复合材料表现出较好的综合性能.

In-Situ Synthesis and the Vacuum Electrical Performances of Cr2Nb/CuCr Composite

The Cr2Nb/CuCr composites with different Cr2Nb contents were prepared by the vacuum sintering and infiltration method. The microstructure of the composites was characterized by X-ray diffraction (XRD) and scanning electron microscope (SEM), and the effects of in-situ synthesized Cr2Nb on the surface arc motion and erosion morphology of the composites were studied by high speed photography and scanning electron microscope (SEM). The results show that the addition of Cr-Nb composite powder causes a significant improvement in the hardness, conductivity, chopping current, arcing life and breakdown strength. The addition of 7wt% Cr-Nb composite powder can make the cathode spots of the Cr2Nb/CuCr composite distribute more dispersively, decrease the chopping current and prolong the arcing life obviously. In comparison with conventional CuCr alloys, the Cr2Nb/CuCr composites present better overall performance.