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采用Nd∶YAG激光器在45#钢基体上制备了镍基纳米Ni包h-BN/CaF2复合自润滑涂层,利用金相显微镜观察涂层形貌,并运用销-盘式高温摩擦磨损试验机对在不同温度条件下(室温和400℃)的涂层的摩擦性能进行了评价.结果表明:纳米Ni包h-BN有效地改善了BN对基材的润湿性,而加入部分CaF2也大大改善了激光熔池的流动性,形成了具有良好冶金结合和组织致密的熔覆层,显微硬度变化范围在740~900HV0.2之间.复合涂层的摩擦系数较镍基涂层显著降低,但随着温度的升高,涂层的摩擦性能变差.
Nickel-based nano-Ni h-BN / CaF2 composite self-lubricating coatings were prepared on 45 # steel substrates by Nd:YAG laser. The morphology of the coatings was observed by metallographic microscope and the pin-disk type high temperature friction and wear tester The tribological properties of the coatings at different temperatures (room temperature and 400 ℃) were evaluated.The results show that the nano-Ni h-BN can effectively improve the wettability of BN to the substrate, and the addition of some CaF2 is also significant Improved the fluidity of the laser pool and formed a cladding layer with good metallurgical bonding and dense structure with microhardness varying from 740 to 900 HV 0.2.The friction coefficient of the composite coating was significantly lower than that of the nickel based coating , But as the temperature increases, the friction properties of the coating become worse.