Synthesis and cladding of Ni3Al intermetallic on steel substrate by laser controlled reactive synthesis

A laser controlled reactive synthesis process was developed to achieve the synthesis and cladding of Ni3Al intermetallic coating on steel substrates at a lower laser density by utilizing the energy of a exothermic reaction. The clad is continuous and smooth, with few defects and excellent bonding with the steel substrate. Through enhancing the relative compact density of the preplaced powders up to 60%, the dilution ratio can be reduced to be lower than 10% and a product of nearly pure Ni3Al phase can be obtained. Compared with the traditional laser cladding process of other alloys and ceramics without exothermic reaction, the cladding of intermetallic coating by laser controlled reactive synthesis can save a great amount of laser energy.