Effect of Sintering Temperature and Hydrophobic Treatment on the Microstructure and Properties of Copper-Graphite Composites  

作　　者：ZOU Jianpeng WEI Hongming XIAO Cong 邹俭鹏;WEI Hongming;XIAO Cong(State Key Laboratory of Powder Metallurgy,Central South University,Changsha 410083,China;State Key Laboratory for System Integration of High Power AC Drive Electric Locomotive,Zhuzhou 412001,China)

机构地区：[1]State Key Laboratory of Powder Metallurgy,Central South University,Changsha 410083,China [2]State Key Laboratory for System Integration of High Power AC Drive Electric Locomotive,Zhuzhou 412001,China

出　　处：《Journal of Wuhan University of Technology(Materials Science)》2022年第3期305-313,共9页武汉理工大学学报（材料科学英文版）

基　　金：the Open Subject of The State Key Laboratory of Heavy Duty AC Drive Electric Locomotive Systems Integration(No.172195100710)。

摘　　要：Copper-graphite composites were prepared by spark plasma sintering(SPS)using coppercoated graphite powder.Hydrophobic surfaces were successfully constructed by chemical etching and surface treatment.The density,metallographic structure,microstructure,Shore hardness,resistivity,water contact angle,and friction/wear properties of the composites were investigated using the Archimedes drainage method,a metallographic microscope,a scanning electron microscope,a hardness tester,a resistometer,a surface science tester,and a friction tester.The results showed that the relative density and Shore hardness of the copper-graphite composites increased slightly from 90.04%and 56 HSD to 92.66%and 59 HSD,respectively,when the sintering temperature increased from 700 to 900℃.The copper and graphite phases in the copper-graphite composites were uniformly distributed with a continuous and network-like structure at various sintering temperatures.The interface between the copper and graphite was in good condition,without any obvious cracks or voids.The optimum process for hydrophobic surface construction included etching with a 1 mol/L K_(2)Cr_(2)O_(7)-H_(2)SO_(4)solution for 1 min,and soaking in a 0.09 mol/L cetylbenzene sulfonic acid alcohol solution for 1 h.The contact angle of the copper-graphite composite reached 130°.Hydrophobic treatment was beneficial for reducing the friction coefficient(from 0.18-0.19 to 0.13-0.15)and the wear rate(from 4.1-6.2×10^(-3)to 1.1-2.1×10^(-3)mm^(3)/(N·m)),demonstrating obvious antifriction and wear-resisting properties.The resistivities of the hydrophobic-treated samples increased slightly,from(4-8)×10^(-7)Ω·m to(5-15)×10^(-7)Ω·m,meeting the resistivity requirements of copper-graphite composite pantograph sliders and current receiver sliders in actual working conditions.

关 键 词：spark plasma sintering(SPS) copper-graphite composite chemical etching shore hardness friction and wear properties RESISTIVITY 

分 类 号：TB333[一般工业技术—材料科学与工程]