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超音速火焰喷涂过程中产生的残余应力会限制涂层的厚度。在研究中,为了获得高质量WC-Co厚涂层,在超音速火焰喷涂过程中采用了干冰冲击技术,这主要是由于干冰冲击对涂层产生了高效冷却和机械锤平。本研究采用X射线衍射,扫描电镜和能谱能对粉末和涂层得微观结构和相分布进行表征。此外,本文对涂层的硬度、抗滑动摩擦等性能也进行了研究。最后我们得出结论,干冰冲击能有效地细化晶粒尺寸,提高涂层硬度,致密度和抗滑动摩擦性能。本研究采用超音速火焰喷涂和干冰冲击联合的工艺方法喷涂WC-Co粉末,以提高冷却效率和喷涂过程中的类喷丸效应。该方法也可以用来制备厚的WC-Co涂层。本文还研究了涂层的微观组织、相组成和摩擦磨损性能。“,”The residual stresses arising during High Velocity Oxy-Fuel(HVOF) thermal-spraying process usually limit the building up of thick coatings. In this work, dry-ice blasting was combined to HVOF process to deposit high quality thick WC-Co coatings, since it induces to efficient cooling and mechanical peening, etc. Several techniques, including X-ray diffraction, scanning electron microscopy, and energy dispersive spectroscopy, were used to characterize the microstructures and phase distribution of the powders and coatings. In addition, mechanical properties such as hardness and sliding wear resistance were investigated. HVOF sprayed WC-Co coating using dry-ice blasting is characterized by compact construction, grain refinement, high hardness as well as outstanding sliding wear resistance.