ABSTRACT AISI 8620 steel substrates were coated with WC–Co and Cr3C2–NiCr by using the atmospheric plasma spraying (APS) method. Subsequently, surface melting of samples coated with APS was performed at different current values using the plasma transfer arc (PTA) method. Microstructure, microhardness, and wear properties of as-sprayed and surface-modified coatings were investigated. The microstructure of the APS-coated surface had some voids, cracks and nonhomogeneous areas. These defects were eliminated with the PTA surface modification process and microstructural properties of coatings were improved. The wear resistance of PTA modified coatings was also increased. The highest wear resistance and microhardness were obtained in WC–Co coating modified by PTA at a current of 80 A. The wear resistance of this coating was 8.5 times higher than that of the substrate. The coating hardness reached values as high as 980 HV0,1 in this coating.

中文翻译：

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等离子转移弧法大气等离子喷涂金属陶瓷涂层的表面改性

摘要 AISI 8620 钢基体采用大气等离子喷涂 (APS) 方法涂覆 WC-Co 和 Cr3C2-NiCr。随后，使用等离子转移弧 (PTA) 方法在不同电流值下对涂有 APS 的样品进行表面熔化。研究了喷涂态和表面改性涂层的显微组织、显微硬度和磨损性能。APS 涂层表面的微观结构有一些空隙、裂纹和不均匀区域。PTA表面改性工艺消除了这些缺陷，改善了涂层的微观结构性能。PTA 改性涂层的耐磨性也有所提高。PTA 改性的 WC-Co 涂层在 80 A 的电流下获得了最高的耐磨性和显微硬度。 该涂层的耐磨性为 8。比基材高5倍。该涂层的涂层硬度值高达 980 HV0,1。