Microstructure and Properties Analysis of AlCrFeNiV High Entropy Alloy Coating In Situ Fabricated by Laser Cladding

To improve the surface properties of 316 L, AlCrFeNiV high entropy alloy (HEA) coating is in situ fabricated by laser cladding. The optimal process parameters through orthogonal experiment are: laser power of 900 W, scanning speed of 10 mm s −1 , and preheating temperature of 300 °C. Microstructure and properties of HEA coating are analyzed and compared with those of 316 L. HEA coating consisted of body‐centered cubic phase solid solution. Under effects of solid solution strengthening, lattice distortion, and slow diffusion, the microhardness and wear resistance of HEA coating are significantly enhanced. Its microhardness reaches 767 HV 0.1 , 3.8 times higher than 316 L. The specific wear rate is 5.56 × 10 −5 mm 3 N −1 m −1 , representing an 86.26% reduction compared to 316 L. Unlike the severe adhesive wear in 316 L, the wear mechanism is predominantly abrasive wear. Electrochemical corrosion tests show that HEA coating has superior electrochemical corrosion performance. The I corr and E corr of HEA coating in 3.5 wt% NaCl solution are 12.53 nA cm −2 and −205.54 mV, outperforming 316 L. The corrosion mechanisms of HEA coating and 316 L are all pitting corrosion, but HEA coating exhibits smaller pits and better pitting resistance.