A review on coating with high entropy alloy developed by laser energy based surfacing process

Abstract

This review paper discusses about the deposition of coating with high entropy alloy on metallic materials by laser energy based surfacing process. The purpose of coating is to deposit a hard and wear resistant layer of expansive material on the surface of workpiece material without altering the bulk properties of the workpiece to increase its surface properties. The coating with high entropy alloy shows excellent surface characteristics like corrosion resistance, wear resistance and oxidation resistance at high temperature. Due to high power density and fast cooling rate, laser cladding is most suitable technique for synthesis of coating with high entropy alloy. Coating with high entropy alloy is generally developed on titanium alloy, magnesium alloy, aluminium alloy, copper alloy and ferrous alloy by laser based cladding process. In this paper effects of laser process parameters on high entropy alloy coating developed on various industrial materials has been discussed. The various laser parameters which affect the properties of coating with high entropy alloy are laser power density, laser scanning speed, feed rate of powder, argon flow rate, and frequency. The high entropy alloy exhibits effect due to high entropy, effect due to slow diffusion, cocktail effect and effect due to severe lattice distortion, which leads to tailoring of microstructure and exhibits to excellent surface hardness, corrosion resistance and wear resistance. This paper describes about the brief review on benefits of high entropy alloy coating, challenges arises, suggested remedies for future research work and its applications in aerospace, automobile, marine and chemical industries.