Study on the microstructure and mechanical properties of Fe 35 Co 14 Ni 17 Cr 15 Nb 19 and Fe 33 Co 14 Ni 15 Cr 12 Nb 26 high-entropy alloy coatings prepared by TIG

Abstract

In this paper, two groups of high-entropy alloy coatings, Fe₃₅Co₁₄Ni₁₇Cr₁₅Nb₁₉ and Fe₃₃Co₁₄Ni₁₅Cr₁₂Nb₂₆, were prepared on a 304 stainless steel substrate using TIG. Both groups of coatings are composed of FCC + Laves phase and the Laves phase increases with the increase of Nb element content. In the Nb29 coating, a transition from sub-eutectic to fully eutectic structure occurs from the bottom to the top. The average microhardness of the two groups of high-entropy alloy coatings was 508.56 HV_0.5 and 617.64 HV_0.5, respectively, which was increased by 2.3 and 2.8 times compared with the substrate. The two groups of high-entropy alloy coatings were superior to the 304 substrate in wear and corrosion resistance, and the Nb26 coating had the best performance.