镁合金等离子体微弧氧化过程控制的研究

研究AZ31镁合金微弧氧化过程中不同控制参数对膜性能的影响。镁合金微弧氧化中存在一个二次放电过程，它会对已长成的膜起破坏作用。通过改变溶液成分或浓度可对镁合金微弧氧化临界点的出现时间进行控制。在此基础上进一步研究一次放电不同控制过程对膜层性能的影响，发现采用渐进式升压方式能提高膜的致密层和疏松层的比例，但对膜的总厚度影响不大。合适的阴极匹配电压，可减小功耗，降低气孔率，改善膜的性能。

Controlling Process of Plasma Microarc Oxidation on Magnesium Alloy

The phenomena of arc discharge in the process of micro arc oxidation(MAO) on magnesium alloy was investigated.The effects of the proces s parameters on the coating properties were studied.it is found that the seconda ry arc discharge is easily involved in the process of MAO on magnesium alloys an d local destruction of the coating formed before is observed.Fortunately,the sec ondary discharge can be controlled by a suitable experimental procedure.Two meth ods for applying voltage,which was keeping voltage at a constant value and progr ammed voltage method,were used in this study.The effect of the cathode voltage w as also examined.The results show that the effective time of MAO depends on the composition and concentration of electrolytes and programmed voltage method impr oves the properties of coating by increasing the thickness of compact layer of t he coating.The cathode voltage is necessary in controlling the secondary dischar ge.