Na_2SO_4水溶液中Mg-10Gd-2Y-0.5Zr微晶薄膜的电化学腐蚀行为  

Electrochemical Corrosion Behavior of Mg-10Gd-2Y-0.5Zr Microcrystalline Film in Na_2SO_4 Solution

作　　者：王赫男[1] 李瑛[1] 王福会[1] 

机构地区：[1]中国科学院金属研究所金属腐蚀与防护国家重点实验室,沈阳110016

出　　处：《腐蚀科学与防护技术》2010年第6期469-473,共5页Corrosion Science and Protection Technology

基　　金：国家自然科学基金项目(50001013和50671113)资助

摘　　要：利用磁控溅射技术制备了晶粒尺寸为300nm～400 nm的GW102K(Mg-10Gd-2Y-0.5Zr)微晶薄膜.通过动电位极化曲线和电化学阻抗谱(EIS)研究微晶薄膜在0.2 mol/L Na_2SO_4水溶液中的腐蚀行为.极化曲线结果表明,微晶化加速GW102K靶材合金的阴极过程,而抑制其阳极过程.EIS结果表明,微晶化降低GW102K靶材合金在自腐蚀电位下的转移电阻和腐蚀产物膜电阻,从而降低其耐蚀性.微晶化提供大量的晶粒边界,氢原子通过晶粒边界快速扩散,生成氢化物,从而加速GW102K靶材合金的阴极反应速率.此外,微晶化促进金属的阳极溶解,使微晶薄膜表面形成大量均匀的腐蚀产物,从而抑制金属的进一步溶解.Mg-10Gd-2Y-0.5Zr（GW102K） microcrystalline（MC） film with grain size about 300 to 400 nm was fabricated on a glass substrate by magnetron sputtering technique.The corrosion behavior of GW102K MC film and GW102K target alloy in 0.2 mol/L Na_2O_4 solution was investigated by polarization curves and electrochemical impedance spectrum（EIS）.The polarization measurement results showed that the cathodic process was accelerated and the anodic process was decelerated of MC film in comparison with GW102K target alloy.The analysis of EIS measurement revealed that the transition resistance and film resistance were decreased.The corrosion resistance of MC film was decreased at open circuit potential.Large amount of grain boundaries existed in the MC film,which therefore might facilitate the diffusion process of adsorption hydrogen in the MC film.The hydrides could form on the surface of MC film.As a result the cathode process for the MC film was accelerated.It also followed that the microcristallization process might facilitate the anodic dissolution process of metal,which then induced formation of corrosion products on the surface of MC film,and the later might play certain role in inhibiting the further dissolution of metals.

关 键 词：Mg-10Gd-2Y-0.5Zr 微晶薄膜 腐蚀行为 氢化物 磁控溅射 

分 类 号：TG174.2[金属学及工艺—金属表面处理]