Characterization of anodic coating formed on Mg-3Nd-0.2Zn-0.4Zr Mg alloy in alkaline electrolyte

来源期刊：中国有色金属学报(英文版)2008年增刊第1期

论文作者：常建卫 郭兴伍 彭立明 丁文江 彭颖红

文章页码：318 - 322

Key words：Mg-Nd-Zn-Zr alloy; anodizing; corrosion resistance

Abstract: Anodization of rare earth-containing Mg alloy of Mg-3Nd-0.2Zn-0.4Zr (mass fraction, %) (NZ30K) was performed in composite electrolyte containing NaOH, KOH, K₂SiO₃, Na₂SiO₃, NaF, KF etc. The anodic coating was characterized by using X-ray diffraction(XRD), field emission electron scanning microscope(FE-SEM) and electron probe microscopic analysis(EPMA). The corrosion resistance of the anodized alloy and the substrate was evaluated in 5% NaCl solution using electrochemical impedance spectroscopy(EIS). The results of XRD show that the anodic coating is mainly composed of MgO. EPMA indicates that magnesium and oxygen are almost uniformly distributed across the coating, and the fluorine content decreases gradually from the interface of coating-substrate to the surface, whereas the distribution of silicon is reverse to that of fluorine. The results of EIS analysis shows that the anodic coating exhibits the superior corrosion resistance for NZ30K alloy.

基金信息：Program of Shanghai Subject Chief Scientist
the National Basic Research Program of China
China Postdoctoral Science Foundation