Review of the research status and development of laser cladding high-entropy alloys

Laser cladding is a sophisticated surface modification technique that utilizes a high-energy laser beam to simultaneously melt cladding materials and the substrate, forming metallurgically bonded coatings characterized by low dilution ratios, narrow heat-affected zones, and exceptional bonding strength. High-entropy alloys (HEAs), composed of at least five principal elements, exhibit high mixing entropy effects that favor the formation of simple solid-solution structures. These alloys are renowned for their superior mechanical properties, corrosion resistance, and thermal stability. Laser cladding offers unique advantages for fabricating HEA coatings, including grain refinement through rapid solidification, precise compositional regulation, and minimized elemental segregation, while enabling the processing of complex geometries. This paper reviews the recent advancements in laser cladding HEA coatings, with a particular focus on the influence of alloying elements on microstructural evolution and surface properties, as well as the mechanisms by which process parameters affect coating quality. Furthermore, the strengthening mechanisms of ultrasound-assisted vibration technology are critically analyzed. Finally, future research directions are proposed to provide a comprehensive reference for the development and application of high-performance HEA coatings.