In order to further improve the corrosion resistance of the micro-arc oxidization (MAO) film on LA103Z magnesium-lithium alloy, a Mg-Al-Co layered double hydroxide (LDH) film was fabricated on MAO film by an in-situ hydrothermal method. The results showed that with the extension of hydrothermal treatment time, the dense LDH film sealed the micro-pores and cracks in the MAO film successfully. In addition, LDH film treated with a hydrothermal treatment at 90°C for 24 h has the best electrical insulation. The hydrogen evolution rates (mL.cm^–2.h⁻¹) of the LDH/MAO composite films rank as LDH/MAO-24 h ≈ LDH/MAO-30 h (0.12) < LDH/MAO-18 h (0.15) < LDH/MAO-12 h (0.16) < MAO (0.25). Meanwhile, the results of potentiodynamic polarization curves showed that the corrosion potential of LDH/MAO-24 h film increased from –1.5349 to −1.388 V, and the corrosion current density decreased by three orders of magnitude. Therefore, the LDH/MAO film has better corrosion resistance than a single MAO film and adds long-term corrosion resistance to the magnesium alloy, which owes to the sealing effect of LDH on inherent defects and trapping effect on corrosion ions.

为进一步提高LA103Z镁锂合金微弧氧化（MAO）膜的耐腐蚀性能，采用原位水热法在微弧氧化膜上制备了Mg-Al-Co层状双氢氧化物（LDH）膜. 结果表明，随着水热处理时间的延长，致密的LDH膜成功地封闭了MAO膜中的微孔和裂缝。此外，经 90°C 水热处理 24 小时的 LDH 薄膜具有最好的电绝缘性。析氢速率 (mL.cm ^–2 .h ^-1) 的 LDH/MAO 复合薄膜等级为 LDH/MAO-24 h ≈ LDH/MAO-30 h (0.12) < LDH/MAO-18 h (0.15) < LDH/MAO-12 h (0.16) < MAO (0.25) ）。同时，动电位极化曲线结果表明，LDH/MAO-24 h薄膜的腐蚀电位从–1.5349增加到-1.388 V，腐蚀电流密度下降了三个数量级。因此，LDH/MAO膜比单一MAO膜具有更好的耐腐蚀性能，并为镁合金增加了长期的耐腐蚀性能，这是由于LDH对固有缺陷的封闭作用和对腐蚀离子的俘获作用。