晶粒尺寸影响金属钝化行为的研究进展

Effects of Grain Size on Passivation of Metals-A

晶粒尺寸能够显著影响金属材料的力学性能、腐蚀特性及失效行为,其对腐蚀特性及失效行为的影响通常来自于对金属钝化行为的影响。本研究综述了晶粒尺寸对钝化膜化学性质、结构、半导体性质以及钝化膜生长/破坏行为的影响作用,在致钝环境中,晶粒尺寸的减小增加了晶界密度,加快了钝化膜的生成及修复速率,同时降低了钝化膜中的缺陷密度。晶粒细化增强了钝化膜稳定性,有利于金属耐蚀性的提高。

Grain size could significantly affect the mechanical properties,corrosion resistance and failure mode of metals.The changes of corrosion resistance and failure mode were usually attributed to passive films formed on metal surface.In this paper,the effects of grain size on chemical characters,structure,and semiconducting properties of passive films,as well as on films growth/repair and broken were reviewed.In passive environment,the decreasing of grain size increased the concentration of grain boundary,and accelerated the growth and repair of passive films.The defect concentration in passive films also decreased with grains size decreasing.Grain refinement could promote the stability of passive films and therefore improved corrosion resistance of metals.