Preparation and Anti⁃arc Erosion Property of Ag Matrix Electrical Contact Material Reinforced by Novel Ti_(2)Cd  

新型Ti_(2)Cd增强银基电触头材料的制备及抗电弧侵蚀特性

作　　者：SUN Wanjie SHI Yuxin DING Jianxiang REN Wanbin PAN Zhixiong ZHANG Peigen SUN Zhengming 孙万杰;石雨欣;丁健翔;任万滨;盘志雄;张培根;孙正明(安徽工业大学材料科学与工程学院,安徽马鞍山243002;东南大学材料科学与工程学院,江苏省先进金属材料重点实验室,南京211189;哈尔滨工业大学电气工程及自动化学院,哈尔滨150001;佛山市通宝电气精密合金有限公司,广东佛山528100)

机构地区：[1]School of Materials Science and Engineering,Anhui University of Technology,Maanshan 243002,Anhui,China [2]Jiangsu Key Laboratory of Advanced Metallic Materials,School of Materials Science and Engineering,Southeast University,Nanjing 211189,China [3]School of Electrical Engineering&Automation,Harbin Institute of Technology,Harbin 150001,China [4]Foshan Tongbao Electical Precision Alloy Co.,Ltd.,Foshan 528100,Guangdong,China

出　　处：《材料导报》2024年第21期190-196,共7页Materials Reports

基　　金：This work was financially supported by the National Natural Science Foundation of China(52101064);Jiangsu Planned Projects for Postdoctoral Research Funds(2020Z158);Industry-University-Research Cooperation Projects(RH2000002728,RH2000002332,RH2100000263).

摘　　要：Due to their outstanding electrical contact properties,Cd-containing silver-matrix electrical contact materials can meet the requirements of high stability and long life for military defense and aerospace applications.In order to further reduce the Cd content under the premise of meeting the high-performance requirements,in this study,high-purity intermediate Ti_(2)Cd powder of MAX phase(Ti_(2)CdC)was synthesized with a pressureless technique and then applied to reinforce the Ag matrix.The Cd content of the as-prepared Ag/Ti_(2)Cd composites was actually reduced by 38.31%compared with conventional Ag/CdO material.Based on the systematic study of the effect of heat treatment temperature on the physical phase,morphology,interface and comprehensive physical properties of Ag/Ti_(2)Cd composites,the preferred samples(heat treated at 400°C for 1 h)showed high density(97.77%),low resistivity(2.34μΩ·cm),moderate hardness(90.8HV),high tensile strength(189.9 MPa),and exhibited good electrical contact performance after 40000 cycles of arc discharging under severe conditions(DC 28 V/20 A).The results of microscopic morphological evolution,phase change and elemental distribution of the electrical contact surface show that the combination of high stability of Ti_(2)Cd reinforcing phase,good interfacial bonding with Ag matrix and improved melt pool viscosity in the primary stage of arc erosion,results in low and stable contact resistance(average value 13.20 mΩ)and welding force(average value 0.6 N),low fluctuation of static force(2.2-2.5 N).The decomposition and absorption energy of Ti_(2)Cd and the arc extinguishing effect of Cd vapor are the main reasons for the stable arcing energy and arcing time of electric contacts in the late stage of arc erosion.含Cd银基电触头材料由于其优异的电接触性能,可以满足军事国防和航空航天领域对高稳定性和长寿命的要求。为了在满足高性能要求的前提下进一步降低Cd含量,本研究采用无压技术合成了MAX相Ti_(2)CdC的高纯度中间体Ti_(2)Cd粉末,并将其用于增强Ag基体。制备的Ag/Ti_(2)Cd复合材料的Cd含量比传统Ag/CdO降低了38.31%。在系统研究热处理温度对Ag/Ti_(2)Cd复合材料物相、形貌、界面及综合物理性能影响的基础上,优选具有高致密度(97.77%)、低电阻率(2.34μΩ·cm)、中等硬度(90.8HV)和高抗拉强度(189.9 MPa)的400℃热处理样品进行电弧放电测试。在苛刻条件下(DC 28 V/20 A)放电40000次后,电接触表面的微观形态演变、相变化和元素分布结果表明,高稳定性的Ti_(2)Cd增强相与Ag基体间的良好界面结合提高了熔池粘度,保证了电弧侵蚀初期低且稳定的接触电阻(平均值13.20 mΩ)和熔焊力(平均值0.6 N),以及小幅度波动的静压力(2.2~2.5 N)。Ti_(2)Cd的分解吸收电弧能量和Cd气化灭弧作用是电弧侵蚀后期电触点燃弧能量和燃弧时间稳定的主要原因。

关 键 词：low-voltage apparatus Ag matrix composite Ti-Cd compound electrical contact properties arc erosion mechanism 

分 类 号：TG14[一般工业技术—材料科学与工程]