ABSTRACT This investigation focusses on the wear mechanism of as-sprayed and laser treated mullite based coatings, produced by plasma spraying, under sliding wear condition. First, an alumina powder and zircon sand mixture was plasma sprayed to produce a mullite coating. Selected as-sprayed coatings were subsequently laser treated. The tribological performances of both as-sprayed and laser re-melted coatings were assessed using a pin-on-disc wear apparatus. Hardened steel and WC-Co balls served as rubbing counterparts. A plasma sprayed alumina coating was used for bench marking purposes. Plastic deformation was the dominant wear mechanism under low load-low speed condition for both as-sprayed and laser treated coatings. However, at higher loads and speeds the coatings were found to undergo micro-fracture followed by pulverisation. Wear resistance of the coatings improved following laser treatment.

中文翻译：

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激光重熔和非激光重熔等离子喷涂锆刚玉粉末混合物的摩擦学性能

摘要 本研究的重点是在滑动磨损条件下，通过等离子喷涂生产的喷涂和激光处理的莫来石基涂层的磨损机制。首先，等离子喷涂氧化铝粉末和锆英砂混合物以产生莫来石涂层。选定的喷涂涂层随后进行激光处理。使用销盘式磨损装置评估喷涂态和激光重熔涂层的摩擦学性能。硬化钢和 WC-Co 球用作摩擦对应物。等离子喷涂氧化铝涂层用于基准标记目的。塑性变形是低负载低速条件下喷涂和激光处理涂层的主要磨损机制。然而，在更高的负载和速度下，发现涂层会发生微破裂，然后粉化。