Investigation of microstructure and properties of FeCoCrNiAlMox alloy coatings prepared by broadband-beam laser cladding technology

Abstract

FeCoCrNiAlMox (x = 0, 0.25, 0.5, 0.75, 1.0, molar ratio) alloy coatings were prepared on 2Cr13 steel substrates by wide-beam laser cladding, aiming to investigate the effects of different Mo addition amounts on the microstructure, phase composition, microhardness, and corrosion resistance of the coatings. The results show that all the coatings are of good quality without cracks or pores. Due to the dilution of the substrate, the actual composition of the coatings deviates from the designed composition to different degrees. The main constituent phase of different coatings was body-centered cubic solid solutions, which does not change with increasing Mo content. The middle part of the Mo0, Mo0.75, and Mo1.0 coatings consists of columnar crystal and Cr-rich needle-like precipitates, but the middle part of Mo0.25 and Mo0.5 coatings has a typical dendrite structure. There is not much difference in the alloy composition between dendrite and interdendrite, and the hardness and corrosion resistance of Mo0.25 and Mo0.5 coatings are basically the same. Among the coatings investigated in our study, the Mo1.0 coating has the greatest hardness and best corrosion resistance in 0.5 mol/L HCl solution.