Influences of Changes in Element M (M=Mo, Cu, and Al) on CoCrFeNiTi-based High Entropy Alloys by Laser Cladding under Different Process Parameters

Abstract

Excellent alloys were prepared to explore the effects of different additions of element M on CoCrFeNiTi-based high entropy alloys by laser cladding under different process parameters. The preset-powder method was used to prepare CoCrFeNiTi_0.5M_0.5 (M=Mo, Cu, and Al) coating in the work. The material properties of high entropy alloys were calculated based on the first principle. After that, the influence mechanism of the addition of M on the CoCrFeNiTi-based high entropy alloy was explored by experiments. The phasing standards of coatings added with M were calculated according to the first principle. It was predicted that CoCrFeNiTi_0.5Mo_0.5 coating and CoCrFeNiTi_0.5Cu_0.5 coating had high hardness and toughness, respectively. All six high-entropy alloys were stable in mechanics. The optimal process parameter coating was selected by the all-factor test based on excellent hardness and shaping quality. The results were consistent with those by theoretical calculations. The cocktail effect of high-entropy alloys was explored by analyzing the effect of different elemental additions on the overall performance of coatings. Results showed that the CoCrFeNiTi_0.5Mo_0.5 coating had high wear resistance and local elastic modulus. The friction mass loss and local elastic modulus were 0.0410 mm3 and 279.0444 GPa, respectively. The CoCrFeNiTi_0.5Cu_0.5 coating had high toughness and corrosion resistance. The resilience and free corrosion potential were 81.6473 nm and -0.730 V, respectively. The CoCrFeNiTi_0.5Al_0.5 coating had good crack resistance. Plastic storage energy was 30071.5097×10-15 J. Research results provided a theoretical basis for preparing high entropy alloy reinforced coatings by laser cladding.