采用端面带孔电极进行电火花沉积制备自润滑涂层

Self-lubricating Coating Prepared by Electrospark Deposition Using Electrode with Drilled Holes at End Face

采用端面带孔电极,在孔中填充MoS2,利用电火花沉积(ESD)方法在高速钢基体上制备Cu-MoS2自润滑涂层。分析自润滑涂层的成分及微观形貌,研究电容、沉积时间对自润滑涂层厚度的影响,以及自润滑涂层的摩擦性能和磨损机理。结果表明:采用这种电极制备的自润滑涂层中只存在MoS2和Cu。其微观形貌显示,自润滑涂层表面凹凸不平,并存在气孔,呈现典型的电火花沉积特征;在第3挡电容下,自润滑涂层的表面质量最好。随着电容、沉积时间的增加,涂层厚度出现先增加后下降的规律。在第3挡下制备的自润滑涂层的摩擦因数最小,随着摩擦时间的增加,在第1挡和第3挡下制备的自润滑涂层的摩擦因数都比较稳定,而在第5挡下制备的自润滑涂层的摩擦因数具有明显的上升趋势。SEM照片表明,磨损表面具有滑移剪切的现象。

Cu-MoS2 self-lubricating coatings were prepared on high speed steel by electro-spark deposition（ESD）by electrode with drilled holes at the end of faces.The holes were filled with MoS2.The composition and micro morphology of the coatings were analysed.The effects of capacitance and deposition time on coating thickness were studied,and also the friction performance and wear mechanism were studied.The results show that there is nothing but MoS2 and Cu exist in the coating fabricated by this way.The micrographs show that the coating surface is uneven and many pores existing on the surface,showing typical characteristics of ESD;the surface quality is the best when it was prepared in the 3 rd grade capacitance.Coating thickness firstly increases and then decreases with the increase of capacitance and deposition time.The self-lubricating coating prepared in the 3 rd-grade capacitance has the lowest friction coefficient.The friction coefficients of the self-lubricating coatings prepared in the1 st and the 3 rd grades stay almost constant with the increase of friction time.The friction coefficient of self-lubricating coatings prepared in the 5 th grade show a clear upward trend when friction time increases.Scanning electron microscope images show shear-slip phenomenon on the wear surface.