【摘要】 采用六偏磷酸盐体系在AZ91压铸镁合金表面制备了一系列微弧氧化膜层。研究了(NaPO3)6和NaOH质量浓度、电流密度以及氧化时间对微弧氧化膜生长规律的影响,并通过扫描电镜、中性盐雾试验等方法研究了微弧氧化膜层形貌特征及耐蚀性能。结果表明:本试验所制备的微弧氧化膜层的耐蚀性属于尚耐蚀和可用等级,与基体合金相比有大幅度提高。采用六偏磷酸盐体系在AZ91压铸镁合金表面制备耐蚀性微弧氧化膜的最佳工艺参数如下:(NaPO3)6质量浓度为2 g/L,NaOH质量浓度为6 g/L,电流密度为6 A/dm2,氧化时间为10m in。更多还原

【Abstract】 A series of micro-arc oxidation（MAO） layers was produced on the surfaces of die cast magnesium alloy AZ91 in hexametaphosphate electrolyte.The effects of concentrations of sodium hexametaphosphate and sodium hydroxide,current density and the oxidation time on MAO layers growth were discussed.The surface features and corrosion resistance of the MAO layers were analyzed using scanning electron microscopy and neutral salt spray test.The results show that the corrosion resistance of die cast magnesium alloy AZ91 is greatly improved by MAO treatment in comparison to the substrate.The optimum technological parameters for producing MAO layers in hexametaphosphate electrolyte were given as follows: 2 g/L（NaPO₃）₆,6 g/L NaOH,current density: 6 A/dm²;oxidation time: 10 min.更多还原