In this work, laser cladding of a Ni-based superalloy powder (Inconel 718) on a Fe-based superalloy (A-286) substrate was performed. The microstructural evolution was studied by optical and electron microscopy techniques, aided by energy dispersive spectroscopy. Additionally, the microhardness along the as-deposited parts was analyzed and correlated with the observed microstructure. It was found that other than austenitic dendrites, Nb-rich carbides, interdendritic Laves networks, and Ti (C, N) were formed; the latter was aided by the presence of pre-existing TiC particles in the substrate. Additionally, a slag oxide layer was seen on the clad surface of the fusion zone. The formation mechanisms of an unmixed zone in the shape of beach and peninsula are discussed.

中文翻译：

---

Inconel 718 粉末在 A-286 基材上的异种激光熔覆：微观结构演变

在这项工作中，在铁基高温合金 (A-286) 基底上进行了镍基高温合金粉末 (Inconel 718) 的激光熔覆。在能量色散光谱的辅助下，通过光学和电子显微镜技术研究了微观结构的演变。此外，分析了沿沉积部件的显微硬度，并将其与观察到的微观结构相关联。发现除奥氏体枝晶外，还形成了富Nb碳化物、枝晶间Laves网络和Ti（C，N）；后者得益于基板中预先存在的 TiC 颗粒的存在。此外，在熔合区的包层表面看到了炉渣氧化层。讨论了海滩和半岛形状的非混合带的形成机制。