中文摘要：

为提高K403镍基高温合金的高温耐磨损能力,采用大气等离子喷涂在镍基上制备了金属间化合物MoSi2涂层,比较分析了基体和涂层与Al2O3配对摩擦副在1100℃下的高温摩擦磨损性能,并采用X射线衍射仪和扫描电镜对摩擦磨损表面进行了物相、形貌和成分分析,进而分析了基体和涂层的磨损机理。研究结果表明：K403合金的摩擦因数在0.35～0.5范围内变化,而MoSi2涂层的摩擦因数在0.65左右波动;MoSi2涂层的磨损率约是基体材料的0.5倍,涂覆MoSi2涂层后,提高了镍基高温合金耐高温磨损能力;镍基合金的高温摩擦磨损机制主要为氧化磨损和疲劳断裂,载荷较小（10N）时,MoSi2涂层的磨损机制主要表现为氧化磨损,较大载荷（40N）时,MoSi2涂层的磨损机制主要表现为氧化磨损和疲劳脆性断裂。

英文摘要：

In order to improve the wear resistance of K403nickel-based alloy at high temperature in air,a molybdenum disilicide coating was prepared on its surface by air plasma spraying.Phase com-position,morphology and component of the worn surface were observed by scanning electron micro-scope（SEM）with energy dispersive spectrometer（EDS）and X-ray.The friction and wear proper-ties of the bare K403alloy and MoSi2coating at 1100℃ were also studied.Results show that the fric-tion factor of K403alloy ranges from 0.35to 0.5and that of MoSi2coating fluctuates around 0.65.The wear rate of MoSi2coating is about half of that of K403alloy.Compared with the bare K403al-loy,the wear resistance of substrate was improved after coated MoSi2coating.The wear mechanism of nickel-based alloys is oxidation wear and fatigue fracture.When the load is smaller（10N）,the main wear mechanism of MoSi2coating is oxidation.However,the main wear mechanism of MoSi2 coating is oxidation and brittle fracture when the load is higher（40N）.