Effect of ZrO 2 Particles on the Microstructure and Ultrasonic Cavitation Properties of CoCrFeMnNi High-Entropy Alloy Composite Coatings.

CoCrFeMnNi-XZrO₂ (X is a mass percentage, X = 1, 3, 5, and 10) high-entropy alloy composite coatings were successfully prepared on 0Cr13Ni5Mo martensitic stainless steel substrates using laser cladding technology. The phase composition, microstructure, mechanical properties, and cavitation erosion behavior of the composite coatings under different contents of ZrO₂ were studied. The mechanism of ZrO₂ particle-reinforced cavitation corrosion resistance was studied using ABAQUS2023 finite element software. The results show that the phase structure of the composite coating organization is composed of FCC phase reinforced by ZrO₂ phase. The addition of ZrO2 causes lattice distortion. The coatings have typical branch crystals and an equiaxed crystal microstructure. With the increase in ZrO₂ content, the microhardness of the composite coatings gradually increases. When X = 10%, the coating's microhardness reached 348 HV, which was 95.53% higher than the high-entropy alloys without ZrO₂ added. Adding ZrO₂ can prolong the incubation period of high-entropy alloys; the high-entropy alloy composite coating with 5 wt.% ZrO₂ exhibited the best cavitation resistance, with a cumulative volume loss rate of only 15.74% of the substrate after 10 h of ultrasonic cavitation erosion. The simulation results indicate that ZrO₂ can withstand higher stress and deformation in cavitation erosion, reduce the degree of substrate damage, and generate higher compressive stress on the coating surface to cope with cavitation erosion. [ABSTRACT FROM AUTHOR]