Enhanced bond strength for micro-arc oxidation coating on magnesium alloy via laser surface microstructuring

Abstract This paper presents a one-stop laser surface texturing (LST) method for in situ micro-arc oxidation (MAO) coating on magnesium substrates to enhance the bond strength. The results show that the pore density of the MAO coating is significantly reduced, while the surface roughness is decreased from 1.89 μm to 0.97 μm after laser processing. Moreover, the peeling rate of the MAO coating after the LST is decreased by 68.6% and the bond strength of the mesh texture coating is increased by 35.7% comparing to that of the as-received coating, in which the laser-textured surface does not affect the corrosion resistance of the MAO coating.