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热喷涂碳化铬涂层广泛应用于高温耐磨环境。在这样高温的恶劣环境下，许多相会产生分解、氧化以及涂层组织变化，从而影响其耐磨性。尽管可以认为Cr3C2-NiCr涂层在高温条件下的组织分解将取决于喷涂微观结构和喷涂参数，但在这方面的研究较少。本文旨在设计出更好的喷涂参数，以提高碳化铬涂层在高温滑动磨擦磨损条件下的显微结构性能。通过X-射线衍射（XRD）和扫描电子显微镜（SEM）观察两种Cr3C2-NiCr相所形成的涂层组织，并且观察飞行颗粒的温度和速度。本文研究了800％下滑动摩擦行为与喷涂参数和涂层微观结构的关系，同时测量涂层在滑动磨擦前后的维氏硬度（300gf）。“,”Chromium carbide-based thermally sprayed coatings are widely usea tor nigh temperature wear applications. In these extreme environments at those temperatures, several phenomena will degrade, oxidize and change the microstructure of the coatings, thereby affecting their wear behaviour. Although it can be easily conceived that the Cr3C2-NiCr coating microstructure evolution after high temperature exposure will depend on the as-sprayed microstructure and spraying parameters, very little has been done in this regard. This study intends to develop a better understanding of the effect of spraying parameters on the resulting chromium carbide coating microstructure after high temperature operation and high temperature sliding wear properties. The microstructures of different coatings produced from two morphologies of Cr3C2-NiCr powders and under a window of in-flight particle temperature and velocity values were characterized through X-ray diffraction (XRD) and scanning electron microscopy (SEM). Sliding wear at 800℃ was performed and the wear behavior correlated to the spraying parameters and coating mierostructure. Vickers microhardness (300 gf) of the coatings before and after sliding wear was also measured.