This study focuses on China’s domestically developed K452 alloy. Using Si3N4 ceramic balls as the counterface material, the tribological properties of the K452 alloy were investigated after heat treatment over a wide temperature range (RT–800 ◦C), and the wear mechanisms were analyzed. The results show that the heat treatment process enhances the material hardness slightly by promoting the dissolution of the γ′-strengthening phase and the precipitation of the η phase. From RT to 600 ◦C, the wear rate of the K452 alloy remains at a relatively low level, on the order of 10−6 mm3·m−1·N−1. Compared with the as-cast condition, intermediate treatment exhibits a significant reduction in the wear rate. Compared with traditional processes, it reduces one step of heat treatment. This improvement is attributed to the precipitation of the uniformly fine η phase, along with the re-dissolution of the γ′-strengthening phase. When the testing temperature is raised to 800 ◦C, the tribological performance of the K452 alloy deteriorates significantly, with the wear rate increasing to the order of 10−5 mm3·m−1·N−1. Microstructural characterization confirms that the in situ formations of dense Cr2O3 and Al2O3 oxide films during friction are the primary mechanism for improved wear resistance from RT to 600 ◦C. But when the temperature rises to 800 ◦C, the dynamic equilibrium of the oxide layers is disrupted, leading to oxidative wear becoming the dominant mechanism.
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