Preparation of red micro-arc oxidation coating with good decorative effect and anticorrosive performance on magnesium alloy
[Introduction]There are few reports on the decorative effect of micro-arc oxidation for magnesium alloys.[Method]A red ceramic film was prepared on the surface of ZM5 magnesium alloy by micro-arc oxidation.The effects of the mass concentrations of Na2SiO3 as main salt and CuSO4 as coloring agent,different complexing agents,and oxidation duration on the properties of micro-arc oxidation film were studied.[Result]The composition of micro-arc oxidation electrolyte was optimized as follows:Na2SiO320 g/L,CuSO40.5 g/L,disodium ethylenediaminetetraacetate 0.5 g/L,and NaF 0.5 g/L.The red ceramic film obtained by micro-arc oxidation at a current density of 3.5 A/dm2 for 25 min is compact,about 31.4 μm thick,mainly composed of MgO,Mg2SiO4,and CuO,and durable in copper-accelerated acetic acid salt spray test for 48 hours.[Conclusion]The red micro-arc oxidation film on ZM5 magnesium alloy has better corrosion resistance than the white one prepared in the CuSO4-free electrolyte.
NETL
NSTL
万方数据
