Effects of processing parameters on zinc-immersion effects in pretreatment process and of current density on Al plating layer in electroplating process were analyzed for Magnesium alloy. The surface and fracture morphologies of zinc-immersion layer and electroplating layer on the surface of the alloy were observed by SEM （scanning electron microscope） and EDS （energy dispersive spectrum）. Based on analyses of mechanical properties and composition

the pretreatment sketch of magnesium alloy and current density in subsequent electroplating process were designed. The results indicate that Al-plating layer with desirable bonding and high purity as well as uniformly compact structure on surface of Mg alloy can be obtained in ZnSO4-K4P2O7 solution for 7 min at 75℃

and with 3.5

4

.1 A/dm2 during electroplating process.