KOH对镁合金微弧氧化过程及膜层耐蚀性的影响

Effect of KOH on MAO Process and Corrosion Resistance of MAO Coatings

在微弧氧化电解液中引入了KOH添加剂,并在镁合金表面制备了陶瓷膜层,研究了KOH浓度对微弧氧化过程中的膜层生长及膜层耐腐蚀性能的影响。结果表明:在镁合金微弧氧化电解液中引入KOH添加剂可以有效降低微弧氧化过程的起弧电压和工作电压,但是KOH浓度过高会使起弧电压增大;KOH的引入会使膜层中的大尺寸孔隙数目减少,孔隙率提高。为了得到较高的膜层生长速率和较好的耐蚀性,电解液中的KOH剂量以1～3 g/L为宜。

KOH addition was introduced into the electrolyte and ceramic coating has been fabricated on magnesium alloy.Effect of KOH on MAO process and corrosion resistance was focused on.The results show that the introduction of KOH could lower the arcing voltage and working voltage of MAO process.However a too high concentration of KOH will lead a high arcing voltage.With KOH additive in the electrolyte the number of micropore decreases and the surface porosity increases.In order to get a higher coating forming velocity and better corrosion resistance,the concentration of KOH is 1-3 g/L.