Current-carrying friction performance of Cu-Graphite-CNTs in wind power slip rings at low currents
SHI Xiongwei2, ZHANG Xin1, KANG Xiao3, WU Liuchen1, XIAO Li2
1. School of Materials Science and Engineering, Xinjiang University, Urumqi 830017, China;
2. School of Mechanical Engineering, Xinjiang University, Urumqi 830017, China;
3. State Key Laboratory of Powder metallurgy, Central South University, Changsha 410083, China
Abstract：This study prepared Cu-Graphite-CNTs composites with varying composition ratios (CNTs mass fraction is 0.1%-1%, Graphite mass fraction is 10%-20%), and current-carrying friction tests were conducted at 0, 1, 3, and 5 A. The friction and wear behavior of the composites was characterized using scanning electron microscope, energy dispersive spectrometer, and Raman spectrometer. And the effects of composition ratios and current on the current-carrying friction performance were investigated. Results indicate that current indirectly affects friction performance by influencing the continuity and integrity of the lubricating film. At 0 A, a fragmented film induces adhesive-abrasive wear, resulting in a high and fluctuating friction factor. Between 1-3 A, moderate Joule heating promotes lubricating film formation, effectively isolating interfaces and suppressing wear. At 5 A, excessive Joule heating causes cracks and film detachment, exacerbating thermal fatigue-adhesive wear. The lubricating film exhibits maximum stability when 0.5% CNTs+10% Graphite (mass fraction) synergize with a 3 A current. This study provides theoretical support for designing high-performance mechanical-electrical composites for wind power slip rings.
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2025, Vol. 30 
