15 / 2021-06-22 11:17:54

Effect of Mo on the Microstructures and Properties of CoCrFeNiMox High Entropy Alloys Coatings Manufactured by Laser Cladding

Laser cladding; high entropy alloys; CoCrFeNiMox; Structures; Wear resistance; Corrosion resistance.

Laser cladding technology was applied to prepare CoCrFeNiMo_x (x=0, 0.25, 0.5 and 0.75) coatings successfully. The phase structures, microstructural characteristics, microhardness distributions, wear resistance and corrosion resistance were investigated. FCC phase solid solution was the main phase structure while interdendritic σ phase was precipitated in Mo_0.5 and Mo_0.75 coatings. In Mo-free cladding coating, obvious solidification boundaries were generated and cellular dendrites were arranged in order with some precipitated fine polyhedral particles. In Mo_0.5 coating, strip σ phase were precipitated along the intergranular while interdendritic σ phase almost occupied the grain boundaries and then connected into a network in Mo_0.75 coating. Microhardness, wear resistance and corrosion resistance of CoCrFeNiMo_x coatings were obviously enhanced proportional to the content of Mo element.