Preparation of deposited coating of Fe-Al inter metallic compound by laser cladding

Two kinds of Fe-Al intermetallic coatings were prepared on steel substrate by laser cladding with powders of Fe₃Al and mixed powders of Fe-based alloy and Al.The microstructure and phase constitution of the coating and the interface between coating and subsurate were studied with SEM,EDX and X-ray analysis.Coatings jointed metallurgically with the substrate were obtained with both methods,and cracks were found in the cladding with powders of Fe₃Al and a few pores were found in the synthesize cladding of mixed powders of Fe-based alloy and Al,but no cracks were found in the latter.Cladding microstructure of the former consisted of coarse equiaxed grain groups,which consisted of a large amount of banding fine Fe₃Al grains and some neighbouring banding grains have the similar orientation.The cladding microstructure of the latter consists mainly of uniform and fine dendrites,in which the atom ratio of Fe:Al:Ni:Cr:Si is about 55:24:8:8:5.