Ag/Cr_(2)AlC电接触材料的微观组织与耐电弧侵蚀性能  

Microstructure and Arc Erosion Resistance Properties of Ag/Cr_(2)AlC Electrical Contact Materials

作　　者：汪丹丹 朱泓羽 魏坤霞 魏伟 田无边[2] 孙正明[2] WANG Dandan;ZHU Hongyu;WEI Kunxia;WEI Wei;TIAN Wubian;SUN Zhengming(School of Materials Science and Engineering,Changzhou University,Changzhou 213164,Jiangsu,China;School of Materials Science and Engineering,Southeast University,Nanjing 211189,Jiangsu,China)

机构地区：[1]常州大学材料科学与工程学院,江苏常州213164 [2]东南大学材料科学与工程学院,南京211189

出　　处：《材料导报》2024年第21期185-189,共5页Materials Reports

基　　金：国家自然科学基金(52302057);江苏省自然科学基金青年项目(BK20220627);常州市应用基础研究项目(CJ20210114);江苏省高等学校自然科学研究面上项目(21KJB430001)。

摘　　要：Ag基电接触材料被广泛应用于低压电路控制器件中,在电路中起承载、分断、闭合电流的作用。Cr_(2)AlC作为M_(n+1)AX_(n)相的典型代表之一,兼具金属和陶瓷的优良性能,有望成为Ag基电接触材料中优良的增强相。本项目采用粉末冶金法制备Ag/Cr_(2)AlC复合材料,表征其微观组织,探究其界面反应,并研究材料的物理性能和耐电弧侵蚀性能。结果表明,由于Al原子的弱结合,经烧结,Ag与Cr_(2)AlC发生明显的界面反应,生成Ag_(3)Al和Cr-C化合物。相比于生坯,Ag/Cr_(2)AlC熟坯的密度和硬度下降,分别为9.04 g/cm^(3)和(78.9±5.5)HV,且由于界面反应的发生,材料的电阻率为(141.9±0.4)×10^(-9)Ω·m。电弧侵蚀结果表明,Ag/Cr_(2)AlC材料经电弧侵蚀生成Al_(2)O_(3),Ag发生熔融喷溅,产生明显凸起,Ag/Cr_(2)AlC的质量损失为6.25%。Ag-based electrical contact materials are widely used in low-voltage circuit control devices,serving the role of carrying,breaking,and closing electrical currents in circuits.Cr_(2)AlC,as a representative of the M n+1 AX n phases,possesses a combination of the excellent properties of both metals and ceramics,making it a promising reinforcing phase in Ag-based electrical contact materials.In this work,Ag/Cr_(2)AlC composites were prepared using powder metallurgy method.The microstructure including interfacial reactions,the physical properties and arc erosion resistance were investigated.The results indicated that due to the weak bonding of Al atoms,significant interfacial reactions occurred between Ag and Cr_(2)AlC after sintering,resulting in the formation of Ag_(3)Al and Cr-C compounds.In comparison to the green bodies,the density and hardness of the sintered Ag/Cr_(2)AlC were reduced,i.e.,9.04 g/cm^(3)and(78.9±5.5)HV,respectively.However,due to the occurrence of interfacial reactions,the electrical resistivity of the Ag/Cr_(2)AlC substantially increased to(141.9±0.4)×10^(-9)Ω·m.Arc erosion tests revealed that the mass loss of the Ag/Cr_(2)AlC was 6.25%,and the main arc erosion product was Al_(2)O_(3).Meanwhile,Ag undergone melting and sputtering,resulting in a noticeable protrusions.

关 键 词：电接触材料 MAX相 Ag/Cr_(2)AlC 界面反应 耐电弧侵蚀 

分 类 号：TQ174[化学工程—陶瓷工业]