以所制AlCl3?NaCl复盐为铝源、MgCl2?6H2O脱水所制熔盐为电解质，电解共沉积制备镁铝合金. 结果表明，当复盐中AlCl3摩尔分数小于0.4时，其在高温下相对稳定，加入高温电解质中可有效减小AlCl3的挥发损失；采用AlCl3摩尔分数小于0.5的AlCl3?NaCl复盐作铝源所制镁铝合金的铝含量比直接以AlCl3为铝源所制镁铝合金提高了9.5%以上，AlCl3利用率明显提高，有效减小了铝含量与理论值的偏差；随熔盐电解质中AlCl3浓度增加，所制镁铝合金中铝含量增加，二者呈良好的线性关系，所制Mg?13%Al合金成分宏观分布较均匀，晶粒大小为50?100 ?m.

Mg?Al alloy was prepared using electrochemical co-deposition method with AlCl3?NaCl double salt as Al source and molten salt prepared by the dehydration of MgCl2?6H2O as the electrolyte. The results showed that the AlCl3?NaCl double salt was relatively stable at high temperature when AlCl3 molar fraction was less than 0.4. The volatile loss of AlCl3 could be effectively reduced when using AlCl3?NaCl double salt as Al source to feed into molten system of high temperature. When the mole fraction of AlCl3 in the double salts was less than 0.5, the usage efficiency of AlCl3 was high in the process of preparation Mg?Al alloy, and Al content in Mg?Al alloy was increased by 9.5% at least compare with those alloys prepared by using AlCl3 as Al source, the deviation from theoretical value of Al content in Mg?Al alloy reduced. Al content in Mg?Al alloy increased linearly with the increase of the AlCl3 content in the molten salt, and the Mg?13%Al alloy has relatively uniform element distribution at macro level, and the grain size of alloy was 50?100 ?m.