两种CuCr(75/25)触头材料的力学性能和断裂特性对触头电接触性能的影响  

The Influence of Mechanical Properties and Fractographs of CuCr(75/25) Contact Materials on the Contact Performance

作　　者：苗柏和[1] 张艳[1] 刘国勋[1] 王文斌 李刚 山瑛 卜小侠 

机构地区：[1]北京科技大学,北京100083 [2]陕西斯瑞工业有限责任公司,西安710077

出　　处：《电工材料》2006年第4期3-7,15,共6页Electrical Engineering Materials

摘　　要：使用标准的拉伸试验与冲击试验测量了两种真空开关管用CuCr(75/25)触头材料的力学性能,并用光学显微镜和配有X射线能谱仪的扫描电子显微镜分析了两种触头材料的断裂特性。结果表明,真空熔铸Cu_25Cr合金触头材料的抗拉强度、塑性、冲击强度都明显高于混粉压制烧结的CuCr25粉末冶金触头材料。两种触头材料的断口金相显示了不同的断裂机理,即Cu_25Cr合金材料是以典型的韧窝状断裂为主,而CuCr25粉末冶金触头材料则以Cr颗粒本身的解理断裂和Cr颗粒与Cu基体间的界面断裂为主。同时,讨论了强度、塑性以及Cu/Cr两相的界面结合强度对触头材料接触性能的影响,这些结果将有助于进一步理解为什么Cu_Cr合金触头材料在中国已经成为广泛接受和采用的并将成为全世界范围内中压真空断路器的真空开关管首选的触头材料。Mechanical properties of two sorts of CuCr （75/25） contact materials adopted widely for vacuum interrupters were determined by standard tensile test and impact test, and fracture characteristics of these two materials after tests were analyzed by optical and SEM equipped with EDS. It was shown that the tensile strength, ductility and impact strength of Cu-25Cr alloy contact material by vacuum casting are superior to that of CuCr25 p/m contact material by sintering technique; Fractographs of these contact materials revealed distinct fracture mechanisms, i.e. dimply ductile fracture of Cu-25Cr alloy materials, in contrast with primarily cleavage fracture of Cr-particles and interracial fracture between Cr and Cu-matrix in CuCr25 p/m materials. The influence of strength, ductility and interracial bonding strength between Cr/Cu phases on the contact performance of contact materials were discussed.

关 键 词：力学性能 断口金相 CUCR触头材料 电接触性能 

分 类 号：TM201.4[一般工业技术—材料科学与工程]