采用大气等离子喷涂方法,制备出WC-Co基体中含有Cu和MoS2固体润滑剂的涂层.分别在200℃、400℃和600℃进行WC-Co-Cu-MoS2涂层和WC-Co涂层的高温摩擦实验,并用扫描电镜对涂层磨损表面进行微观形貌观察.结果表明,当温度为200℃时,在WC-Co-Cu-MoS2涂层磨损表面形成含有润滑剂的致密摩擦产物层,导致涂层的摩擦系数和磨损率均较低.但在400℃和600℃时,润滑剂MoS2由于氧化和挥发而损失,摩擦产物层中形成孔穴缺陷,并变得疏松,失去对涂层的保护作用,涂层摩擦过程趋于恶劣.WC-Co-Cu-MoS2涂层只有在相对较低的温度下(约200℃)才表现出比WC-Co涂层优异的摩擦磨损性能.%WC-Co-based coating containing solid lubricant Cu and M0S2 was fabricated via atmospheric plasma spraying(APS) process. The high temperature tribological properties of the WC-C0-Cu-M0S2 and WC-Co coatings were investigated at 200℃,400℃ and 600℃. Microscopic observation of the coatings after wear was performed using a scanning electron microscopy(SEM). It is concluded that effective solid lubrication behavior was found during the wear tests of WC-C0-CU-M0S2 coating at 200℃ owing to the compact triboreaction layers containing solid lubricant were formed on the worn surface. However, depressed solid lubrication effect was found in 400℃ and 600℃ wear tests attribute to the lost of M0S2 in the triboreaction layers. Some pores and defects were formed in the triboreaction layers as a result of the oxidization and evaporation of M0S2. The triboreaction layers became loosened and unprotec-tive which leading to serious wear damage at 400℃ and 600℃. WC-C0-Cu-M0S2 coating had better frictional behavior comparing with the WC-Co coating only at relatively low temperature (about 200℃).
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