微晶化对纯镁钝化膜特性的影响

Effect of Microcrystallization on Corrosion Behavior of Pure Magnesium

通过阳极极化曲线、Mott-Schottky分析等手段研究铸态纯镁和微晶化纯镁的腐蚀行为.结果表明,微晶化对纯镁的腐蚀行为有着明显地影响.与铸态纯镁相比,微晶化改变了纯镁钝化膜的成长机制,降低钝化膜内的载流子密度和扩散系数,显著地提高钝化膜的耐蚀能力.

For better understanding the effect of microcrystallization on corrosion performance of pure magnesium, the corrosion behavior of pure microcrystalline （MC） magnesium had been studied by means of anodic polarization curves and Mott-Schottky measurement in comparison with its counterpart cast magnesium. The experimental results indicated that microcrystallization had an obvious effect on the corrosion behavior of pure magnesium. In comparison with the cast magnesium, the passive film on the MC magnesium showed different growth mechanism and superior corrosion resistance to pitting corrosion, which might be resulted from lower point defect density and point defect diffusivity of the passive film.