铜表面织构密度对铜/碳配副载流摩擦性能的影响  

Effect of Copper Surface Texture Area Density on Current-carrying Tribological Properties of Copper/Carbon Pair

作　　者：周涛涛 宋晨飞[1,2] 钱志源 张燕燕 任雨龙[1] 宋鹏飞 侯庆华 张永振 ZHOU Taotao;SONG Chenfei;QIAN Zhiyuan;ZHANG Yanyan;REN Yulong;SONG Pengfei;HOU Qinghua;ZHANG Yongzhen(National United Engineering Laboratory for Advanced Bearing Tribology,Henan University of Science and Technology,Henan Luoyang 471023,China;Space Structure and Mechanism Technology Laboratory of China Aerospace Science and Technology Group Co.,Ltd.,Shanghai 201108,China)

机构地区：[1]河南科技大学高端轴承摩擦学技术与应用国家地方联合工程实验室,河南洛阳471023 [2]中国航天科技集团有限公司空间结构与机构技术实验室,上海201108

出　　处：《表面技术》2024年第17期41-49,共9页Surface Technology

基　　金：国家自然科学基金(52275185);中国航天科技集团有限公司空间结构与机构技术实验室开放课题基金(YY-F805202211013);河南省高等学校重点科研项目(22A460015)。

摘　　要：目的碳刷是大型水轮机组、风电、新能源汽车等装备中电机转子供电的唯一通道,在长期服役过程中其碳块磨耗过度,落粉现象严重,探索织构化对铜/碳配副载流性能和摩擦磨损性能的影响,提出改善碳刷服役性能的表面技术。方法在铜环表面制备不同织构密度的圆形微织构,与碳块构成滑动载流摩擦副,研究织构密度对铜/碳配副载流摩擦磨损性能的影响。采用光学显微镜、白光干涉三维形貌仪、扫描电子显微镜等表征手段分析试样的磨损形貌,并通过能谱仪分析铜环表面碳元素分布及含量,揭示织构化对铜/碳配副性能的影响机制。结果当织构密度从0%增至18%时,摩擦跑合时间下降了47.2%,碳块磨损量下降了31.8%,在同等名义接触面积下接触电阻增高了28.7%。结论铜表面织构化有利于收集和储存摩擦过程中产生的碳颗粒,促进碳转移膜的形成,织构密度的增加可有效缩短摩擦跑合时间、降低碳磨损率。由于织构化破坏了铜表面的连续性,且碳转移膜的导电性弱于铜,因此织构密度的增加导致接触电阻升高。铜表面织构化对于提高碳刷磨损寿命、减少落粉量有一定效果。The carbon brush is the only channel for the power supply of motor rotors in hydro turbine units,wind power,new energy vehicles,and other electric equipment.However,long-term service will lead to excessive wear of carbon blocks and serious"powder falling".In this paper,a surface texture modification technology was utilized on the copper surface to modify the wear properties and conductive properties.It was expected to propose a promising method for enhancing carbon brush performance.Here,the sliding current-carrying friction pairs consisted of copper rings and carbon blocks.Circular micro-textures with different texture density were prepared on the surface of the copper ring.The diameter of the texture was 200μm and the depth was about 4.2μm.The tribological and electrical contact properties of copper/carbon pairs were tested at 2 A and 400 r/min.The product of velocity and load per unit area(cm2)was 8.5 MPa m/s and the current density per unit area was about 10 A/cm2,the experimental parameters conformed to the engineering applications of the carbon brush.After the tests,an optical microscope,a white light interference 3D profiler and a scanning electron microscope were used to analyze the wear surface of copper and carbon.The results showed that with the increase of the surface texture density from 0%to 18%,the running time decreased from 36 min to 19 min,the wear amount of carbon block samples decreased from 7.95 mg to 5.42 mg,and the wear area of the carbon block sample decreased from 27.62 mm2 to 18.19 mm2.However,the average real-time contact resistance increased from 0.482Ωto 1.340Ω,the static contact resistance increased from 0.924Ωto 1.189Ω.3D profiles of the copper surface showed that both the wear length and wear depth of carbon decreased,and the texture pits on copper were filled up after sliding.Energy dispersive spectrometer maps showed that the C/Cu atomic number fraction increased from 0.824 to 4.208 with the increase of texture density.The increase of carbon content in texture pits was grea

关 键 词：碳刷 表面织构 载流摩擦 接触电阻 磨损 转移膜 

分 类 号：TH117.1[机械工程—机械设计及理论]