Spherical WC particles are widely employed as hard phases to reinforce metal matrix coatings; however, their deposition during the surfacing process presents a significant challenge, resulting in limited improvements in coating hardness and wear resistance. In this work, these spherical WC as well as spherical/non-spherical WC particles have been used to prepare the WC reinforced nickel-based alloy coatings. The microstructure, mechanical, wear and fracture behavior of these coatings were investigated by detailed characterization. Results showed that spherical WC exhibited rapid sedimentation, and the primary decomposition products existed lump-like W2C. The ultimate decomposition process was based on the exfoliation of the diffusion layer. The spherical WC/Ni coatings exhibited a hardness of 13 GPa and an elastic modulus of 253 GPa, respectively. Notably, the wear rate of these coatings was relatively high, measuring 7.038 × 10−6 mm3/(N·m), while the stress and strain were comparatively low, standing at only 272.5 MPa and 0.72 %. In contrast, spherical/non-spherical WC/Ni coatings demonstrated distinct differential sedimentation behavior. Spherical WC particles settled at the bottom of the coating, whereas non-spherical WC particles were dispersed in the middle and upper regions. The decomposition of non-spherical WC particles was governed by the dissolution and diffusion of W2C, forming a skeleton-braided structure of M7C3, γ, and M23C6 phases on the coating surface. This unique structure increased the hardness of the coating to 21 GPa and the elastic modulus to 369 GPa, while reducing the wear rate to 2.853 × 10−6 mm3 (N · m) −1. In addition, the stress and strain reached 497.10 MPa and 1.97 % respectively, shifting the fracture mode to quasi-cleavage fracture with tear ridges. Overall, the spherical/non-spherical WC/Ni coating exhibited improved deformation resistance and superior wear resistance.

中文翻译：

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通过添加非球形 WC 增强镍基合金涂层，增强球形 WC 增强镍基合金涂层的耐磨性和抗崩损性


球形 WC 颗粒被广泛用作增强金属基体涂层的硬质相;然而，它们在堆焊过程中的沉积带来了重大挑战，导致涂层硬度和耐磨性的改善有限。在这项工作中，这些球形 WC 以及球形/非球形 WC 颗粒已被用于制备 WC 增强镍基合金涂层。通过详细表征研究了这些涂层的微观结构、机械、磨损和断裂行为。结果表明，球形 WC 表现出快速沉降，初级分解产物存在块状 W2C。最终的分解过程是基于扩散层的剥离。球形 WC/Ni 涂层的硬度分别为 13 GPa 和 253 GPa。值得注意的是，这些涂层的磨损率相对较高，为 7.038 × 10−6 mm3/（N·m），而应力和应变相对较低，仅为 272.5 MPa 和 0.72 %。相比之下，球形/非球形 WC/Ni 涂层表现出明显的差异沉降行为。球形 WC 颗粒沉降在涂层的底部，而非球形 WC 颗粒分散在中上部区域。非球形 WC 颗粒的分解受 W2C 溶解和扩散的控制，在涂层表面形成 M7C3、γ 和 M23C6 相的骨架编织结构。这种独特的结构将涂层的硬度提高到 21 GPa，弹性模量提高到 369 GPa，同时将磨损率降低到 2.853 × 10−6 mm3 （N · m） −1。此外，应力和应变达到 497.10 MPa 和 1.97%，将断裂模式转变为具有撕裂脊的准解理断裂。总体而言，球形/非球形 WC/Ni 涂层表现出更好的抗变形性和优异的耐磨性。