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通过高能球磨和感应烧结制备耐高温自润滑IS304涂层,涂层中自润滑相明显细化,其中Ag尺寸为5μm左右,BaF2/CaF2尺寸为1μm左右.研究表明,环境温度和组织对涂层的摩擦性能有较大影响,当温度为20—340℃时,2种涂层的摩擦系数都较高,磨损机理主要为微观脆性断裂;随着温度升高,由于磨损面上形成由氟化物和Ag组成的自润滑膜,涂层的摩擦系数急剧降低.当温度为340—700℃时,由于IS304涂层中润滑相尺寸细小且分布均匀,使得磨损面上形成的润滑膜完整,并且Ag膜尺寸细小、分布均匀,因此IS304涂层的摩擦系数明显低于润滑相粗大的PM304;当温度继续升高至700—800℃时,在摩擦力的作用下,软化的润滑膜表面出现塑性流变,涂层的摩擦系数明显增大.由于PM304涂层的磨损面上的Ag膜尺寸粗大,且Ag膜的塑性流变比氟化物膜更严重,使得PM304涂层的摩擦系数明显大于IS304.
The high temperature self-lubricating IS304 coating was prepared by high energy ball milling and induction sintering, and the self-lubricating phase in the coating was obviously refined, of which the Ag size was about 5μm and the BaF2 / CaF2 size was about 1μm.The results showed that the ambient temperature and the microstructure of the coating The friction coefficient of the two kinds of coating is higher when the temperature is 20-340 ℃, the wear mechanism is mainly micro-brittle fracture; as the temperature rises, And Ag, the friction coefficient of the coating decreases sharply.When the temperature is between 340 and 700 ℃, the lubricating film formed on the wear surface is complete due to the small size and uniform distribution of the lubricant phase in the IS304 coating, and the Ag Therefore, the friction coefficient of IS304 coating is obviously lower than PM304 with coarse lubrication phase. When the temperature continues to rise to 700-800 ℃, plastic flow appears on the softened lubricating film surface under the action of friction As the thickness of Ag film on the wear surface of PM304 coating is thick and the plastic rheology of Ag film is more serious than that of fluoride film, the friction coefficient of PM304 coating is obviously larger than that of IS304.