| Magnesium alloys have important application value and broad application prospect in the automotive,3C, aerospace and military equipment etc, as the light weight high strength, but the poor corrosion resistance and wear resistance, magnesium alloy is limited to applied in industry widely, so it has very important practical significance to improve the corrosion resistance and wear resistance.In this paper, preparation aluminum bronze coating and nickel aluminum bronze composite coating on magnesium suface by laser cladding, and study on the microstructure, phase, micro hardness, wear resistance and corrosion resistance of the coating.Obtained the aluminum bronze coating on AZ31B magnesium alloy by laser cladding, such as well molding, without defects about obvious cracks and stomatal etc. The phase like "bright cross", "petal" and "fish bone" distributed in coating, and the phase is the same, for CuMg2, AlCu, but the phase of "fish bone" is Cu-rich, the maximum hardness is about 370.2HV0.2,increased 6.4 times than substrate, worn mass of coating is 50% of matrix, corrosion rate of coating is 50% of matrix.In order to obtain better performance of coating, add Ni60 powder in aluminum bronze powder with the mass fraction of 10%,30% and 50%. Results show that the composite coatings were gained on AZ31B magnesium alloy, coating has good combination with matrix interface, the micro hardness, wear resistance and corrosion resistance increase significantly following the increase of content of Ni60 powder, when Ni60 to 50%, the phase is similar to "K" phase of nickel aluminum bronze in the composite coating, that is the FeAl3,CuMg2 of Cr-rich, the maximum hardness is about 602.5HV0.2,increased 232HV0.2 than the aluminum bronze coating,11 times than the substrate, worn mass is 60% of aluminum bronze coating,30% of the matrix, corrosion rate is 27% of aluminum bronze coating,12% of the matrix.Ni60 makes composite coating performance improved, and positively than the content of Ni60.
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