Effect of La_2O_3 on electrical friction and wear properties of Cu-graphite composites  

作　　者：莫飞 凤仪 陈阳明 王雨晴 钱刚 豆亚坤 张学斌 

机构地区：[1]School of Materials Science and Engineering, Hefei University of Technology

出　　处：《Journal of Rare Earths》2015年第3期327-333,共7页稀土学报（英文版）

基　　金：Project supported by the Major Research Program of the National Natural Science Foundation of China(91026018);the Doctoral Fund of Ministry of Education of China(2011011110015);the Shanghai City special artificial micro materials and Technology Key Laboratory Open Fund(ammt2013A-7)

摘　　要：Sliding friction and wear experiments using Cu-La2O3-graphite composites against Cu-5 wt.%Ag alloy ring were conducted at a constant sliding speed of 10 m/s, a current density of 10 A/cm2 and a load of 2.5 N/cm2. These composites with different La2O3 and graphite contents were fabricated by hot-pressing. Physical and mechanical properties of the composites were examined. Morphologies of the worn surface of composites were observed using optical microscopy. X-ray photoelectron spectroscopy spectra were used to study compositions of the lubricating film. The results showed that with the increasing addition of La2O3, hardness, flexural strength and electrical resistivity increased, but the relative density dropped. The friction coefficient increased with the increasing addition of La2O3. Composite containing 3 vol.% of La2O3 and 37 vol.% of graphite showed the best wear resistance. The main wear mechanisms of composites were abrasive wear, oxidative wear and adhesive wear.Sliding friction and wear experiments using Cu-La2O3-graphite composites against Cu-5 wt.%Ag alloy ring were conducted at a constant sliding speed of 10 m/s, a current density of 10 A/cm2 and a load of 2.5 N/cm2. These composites with different La2O3 and graphite contents were fabricated by hot-pressing. Physical and mechanical properties of the composites were examined. Morphologies of the worn surface of composites were observed using optical microscopy. X-ray photoelectron spectroscopy spectra were used to study compositions of the lubricating film. The results showed that with the increasing addition of La2O3, hardness, flexural strength and electrical resistivity increased, but the relative density dropped. The friction coefficient increased with the increasing addition of La2O3. Composite containing 3 vol.% of La2O3 and 37 vol.% of graphite showed the best wear resistance. The main wear mechanisms of composites were abrasive wear, oxidative wear and adhesive wear.

关 键 词：Cu-La2O3-graphite composites electrical contacts contact voltage drop friction wear rare earths 

分 类 号：TB333[一般工业技术—材料科学与工程]