电流负载对滑动电接触系统摩擦学行为的影响  

Effect of Current Load on Tribological Behavior of Sliding Electrical Contact System

作　　者：李发强 王东伟 巫英伟[1] 陈晓 陈泽生 杨睿 LI Fa-qiang;WANG Dong-wei;WU Ying-wei;CHEN Xiao;CHEN Ze-sheng;YANG Rui(State Key Laboratory of Multiphase Flow in Power Engineering,Xi'an Jiaotong University,Xi'an 710049,China;Science and Technology on Reactor System Design Technology Laboratory,Nuclear Power Institute of China,Chengdu 610213,China)

机构地区：[1]西安交通大学动力工程多相流国家重点实验室,西安710049 [2]中国核动力研究设计院核反应堆系统设计技术重点实验室,成都610213

出　　处：《表面技术》2023年第8期142-150,共9页Surface Technology

基　　金：国家自然科学基金(52105220);四川省自然科学基金(2022NSFSC1950)。

摘　　要：目的探讨电流对滑动电接触摩擦学行为特性的影响,厘清电流负载与滑动电接触摩擦学行为之间的关系。方法采用黄铜材料为对摩副,在自行设计的摩擦滑动电接触试验机上进行球-面电接触摩擦学试验。分别输入0.2、1、2 A的直流负载,采集界面的摩擦因数、摩擦力、接触电压信号,并分别使用光学显微镜和扫描电镜等设备观察界面的摩擦磨损特性。利用ABAQUS中的热-电-力多场顺序耦合算法模拟试验过程,分析界面电压、温度和切应力的变化特性。结果当电流从0.2 A增至1 A时,界面的摩擦因数在稳定阶段均为0.5左右,同时摩擦力信号也未出现显著差异。当电流负载进一步增至2 A时,摩擦因数增至0.7,摩擦力也显著增大。当电流负载从0.2 A增至2 A时,接触电压从0.1 V增至0.75 V,接触电压的增大倍数与电流的增大倍数不同。磨损分析结果表明,当电流增至2 A时,界面磨损程度加剧,同时导致磨屑堆积,形成局部“摩擦凸台”,且“摩擦凸台”的数量显著增多,直接导致界面黏着区域增大。有限元分析结果表明,当电流增至2 A时,界面温度上升明显,热效应显著,因此剪切力明显增大。结论界面的接触电阻包括收缩电阻和薄膜电阻,在摩擦过程中它们随磨损程度发生变化,因此接触电压不随电流的增大而等比例增大。当电流增至一定程度时对界面的摩擦学行为具有负作用,这是由于电流负载的增加导致界面温升显著,摩擦切应力增大,黏着效应增强,从而加剧了界面的摩擦磨损程度。此研究结果为认识电流负载与滑动电接触摩擦学行为之间的关系提供了理论依据。To study the effect of current load on the tribological behavior of sliding electrical contact system,and further clarify the relationship between current load and tribological behavior of sliding electrical contact system,a series of tribological tests were carried out on a self-designed friction sliding electrical contact tester.Brass material was used as the rubbing pair,and a ball-on-flat configuration was designed to perform the tests.The brass flat sample with the size of 25 mm×25 mm×4 mm was ground and polished to surface roughness Ra≈0.04μm.H62 solid brass ball with diameter of 4 mm was selected as the ball sample.During the test process,the DC current loads of 0.2 A,1 A and 2 A were input to the contact system respectively,then the friction coefficient,friction force and contact voltage signals from the interface were detected and analyzed,and the friction and wear characteristics of the contact surface after test were observed.In addition,the variation characteristics of interface voltage,temperature and shear stress were further analyzed by simulating the test process with thermal-electric-mechanical multi-field coupling algorithm,which was carried out in the finite element analysis software ABAQUS.The test results indicated that when the current increased from 0.2 A to 1 A,there was no significant difference between the friction coefficient and the friction force at the stable stage,and the friction coefficient was kept at 0.5 in the steady stage.When the current load further increased to 2 A,the friction coefficient and friction force increased significantly,the friction coefficient was observed to increase to 0.7.As the current load increased from 0.2 A to 2 A,the contact voltage drop increased gradually from 0.1 V to 0.75 V.It is worth noting that although the current increases by a factor of 10,the contact voltage does not scale up,because the contact resistance of the interface changes with the wear process during triboelectric contact.Therefore,a larger current load causes a higher contact

关 键 词：电接触 滑动 摩擦磨损 表面分析 试验测试 有限元分析 

分 类 号：TH117[机械工程—机械设计及理论]