Influence of Nickel-aluminum Wire Gap on Microstructure and Mechanical Properties of Nickel-aluminum Coating

Rolling and drawing methods were used to prepare nickel-aluminum wires with different gaps.The effect of the gap between nickel and aluminum on the microstructure and mechanical properties of the coating was studied.The microstructure, composition and mechanical properties of the coating were measured by stereo microscope, scanning electron microscope, tensile testing machine and microhardness tester.The results show that as the gap between nickel and aluminum increases, there is no significant change in the structure and porosity of the nickel-aluminum coating.With the increase of the proportion of the Al₂O₃ in coating, the proportion of Ni_xAl_y intermetallic compounds decreases.In terms of mechanical properties, as the gap between Ni and Al increases, the bonding strength of the nickel-aluminum coating decreases and the microhardness increases.