Microstructure modification and improving corrosion resistance of laser surface quenched nickel-aluminum bronze alloy

Abstract Laser surface quenching technology was utilized to modify the surface microstructure of as-cast nickel-aluminum bronze. A supersaturated solid solution layer with a fine-grained size of 30∼50 μm was formed, and its corrosion behavior was studied by electrochemical measurements and long-term immersion corrosion test. It was found that laser surface quenching homogenized the distribution of elements in the constituent phases and eliminated the selective phase corrosion. Due to the formation of a more protective film on laser quenched NAB alloy, the corrosion rate reduced about 42.6 % compared with that of as-cast NAB alloy.