Research status of high-entropy alloys coating prepared by laser cladding

Laser cladding has the advantages of high cooling rate, low dilution rate, metallurgical combination between coating and substrate, etc. In recent years, high-entropy alloys coating with high wear resistance and corrosion resistance prepared by laser cladding has been one of research hotspots in high-entropy alloy field. Firstly, the high-entropy alloys prepared by laser cladding and corresponding microstructures were summarized. Most coatings were composed of solid solution phase, but some alloy coatings still formed amorphous phase. Compared with high-entropy alloys prepared by melting, the microstructure of this coating was more homogeneous, finer and denser. Then, the properties of the coating were introduced, including high hardness and good wear resistance and corrosion resistance. The coating with good wear resistance also had high hardness and certain plasticity. The coatings exhibited excellent corrosion resistance due to the existence of Al, Cr, Si and Co elements which formed the stable oxide film. Then, the effect of alloying elements (Al, Mo, V, Ti, B, Ni, Nb and Cu), cladding parameters (laser power, scanning rate and thickness of prepared layer) and heat treating parameters on the microstructure and properties was reviewed. The effect of cladding parameters on microstructure and properties is fewer and will be one of the key research contents. Lastly, the existing problems and the future research fields of high-entropy alloys coating prepared by laser cladding are prospected. © 2019, Chongqing Wujiu Periodicals Press. All rights reserved.