The micro-arc oxidization（MAO） ceramic layer on LA103 Z Mg-Li alloy was prepared in silicate alkaline electrolyte. The effects of oxidation voltage on microstructure and corrosion behavior of MAO coatings in 3.5% NaCl solution were investigated. The microstructure and phase composition of the coatings were characterized by SEM and XRD. In addition

the corrosion resistance of the ceramic layers was evaluated by hydrogen evolution method and weight loss analysis. The results indicate that the micro-porous morphology of MAO coating is formed gradually after growing for 40 s. Meanwhile

the thickness and micro-pore diameter of the coatings are increased with the enhancement of oxidation voltage

where the "crater" morphologies and the micro-cracks appear on the surface of the ceramic layer. The MAO coating is mainly composed of MgO and Mg

2

SiO

4

phases. The hydrogen evolution rate of MAO coatings prepared with different oxidation voltages after 192 h immersion is presented as follows: v

450 V

<

v

500 V

<

v

550 V

<

v

substrate

. Furthermore

the MAO coating with an oxidation voltage of 500 V has a minimum weight loss rate after immersion for 96 h. It is demonstrated that MAO coating can provide a positive corrosion protection for the substrate and the MAO coating prepared with 500 V has the desirable anticorrosion capacity.