载流条件下镧对Cu-Al2O3复合材料电弧烧蚀性能的影响  

Effect of Lanthanum on Arc Ablation Performance of Cu-Al2O3 Composites under Current-Carrying Condition

作　　者：杜林飞 刘贵民 闫涛 惠阳 Du Linfei;Liu Guimin;Yan Tao;Hui Yang(Department of Equipment Support and Remanufactur-ing,Army Academy of Armored Forces,Beijing 100072,China)

机构地区：[1]陆军装甲兵学院装备保障与再制造系

出　　处：《中国稀土学报》2019年第6期680-688,I0002,共10页Journal of the Chinese Society of Rare Earths

基　　金：北京市自然科学基金项目(2152031)资助

摘　　要：采用高能球磨、放电等离子烧结的方法制备Cu-Al2O3-La复合材料,利用扫描电镜(SEM)、能谱仪(EDS)、显微硬度计、摩擦磨损试验机等设备研究了La含量对复合材料组织、致密度、硬度、导电率、耐电弧烧蚀性能的影响,并探究稀土元素对复合材料载流摩擦中电弧烧蚀现象的影响。结果表明:La元素可以促进Al2O3颗粒的弥散分布,有效防止颗粒团聚,当La含量为0.03%时,颗粒分布状态最佳。与Cu-Al2O3复合材料相比,Cu-Al2O3-0.01La复合材料的致密度、硬度与导电率分别从97.2%,HV174,58.37%IACS提升至97.6%,HV181,64.51%IACS。但随着La含量的增加,复合材料性能不再有明显的提升,La含量为0.02%时,导电率还有一定程度的下降。实验结果显示稀土含量为0.02%时,复合材料的综合性能最佳。电弧烧蚀与载流摩擦试验结果表明:La元素一方面减少了材料表面电弧易击穿区域的相对数量,分散电弧能量,使阴极斑点连续又迅速的运动,提高了复合材料的耐电弧烧蚀性能;另一方面增强材料的力学性能,削弱了磨损表面的片状剥落现象,使摩擦副的接触更加紧密,有效抑制了复合材料载流摩擦磨损过程中的电弧烧蚀现象,提高耐磨性能。Cu-Al2O3-La composites were prepared by high-energy ball milling and spark plasma sintering.Scanning electron microscopy(SEM),energy spectrometer(EDS),micro hardness tester,friction and wear testing machine and other equipment were used for investigating the effect of La content on composites micro-structure,density,hardness,electrical conductivity,arc ablation resistance performance,and effect of La on arc ablation in the process of current carrying friction were studied.The results showed that the La can promote the distribution of Al2O3 particles and effectively prevent particles from agglomerated.The particle distribution become optimal when La content is 0.03%.Compared with Cu-Al2O3 composites,the density,hardness and conductivity of Cu-Al2O3-0.01 La composites increase from 97.2%,HV174 and 58.37%IACS to 97.6%,HV181 and 64.51%IACS respectively.However,the properties of composites are no longer consistent with the increase of La content,the conductivity will decrease to some extent when La content is higher than 0.02%.The results revealed that the composite has the comprehensive performance when the rare earth content is 0.02%.The experiment phenomenon of arc ablation test and current-carrying friction test indicated that,rare earth can reduce the relative number of arc breakdown areas and prompt the arc energy to lower and scattered,which makes the cathode spots movement to be continuous and rapid,and ultimately improve the arc ablation resistance of the composite.Furthermore,La can enhance the mechanical properties of composites,weaken the flaking of wear surface and make the contact of friction pair become closer,which effectively suppresses the arc ablation phenomenon of current-carrying friction process and improves the wear resistance of composites.

关 键 词：高能球磨 放电等离子烧结 Cu-Al2O3-La复合材料 载流摩擦 

分 类 号：TP391[自动化与计算机技术—计算机应用技术]