Study on Mechanical Properties of AlFeCrMoNi1.8Nb1.5 Eutectic High-Entropy Alloy Coating Prepared by Wide-Band Laser Cladding

Abstract

In this study, AlFeCrMoNi1.8Nb1.5 (at.%) eutectic high-entropy alloy (EHEA) coating was successfully prepared on the surface of M2 high-speed steel (HSS) by wide-laser cladding. The effects of laser defocusing amount, laser power, scanning speed, and preset powder thickness on the formation quality of the EHEA coating were studied by the orthogonal experimental design, then the mechanical properties of the coating prepared by water-cooled solidification under optimal process parameters were studied. The experimental results showed that the optimal laser cladding process parameters are defocusing with an amount of −30 mm, laser power of 4 kW, scanning speed of 3 mm/s, and preset powder thickness of 1.5 mm. The substrate exhibited a favorable metallurgical bond with the coating, characterized by a stable interface devoid of any holes or cracks. Furthermore, the coating, which was prepared using water cooling, displayed a finer lamellar eutectic structure comprising FCC and Laves phases. The microhardness of the coating (544 HV0.2) was significantly higher than that of the substrate M2 HSS (~220 HV0.2), accompanied by good wear resistance.