电化学法制备K_2Ti_6O_(13)/TiO_2复合涂层的结构与腐蚀行为  

Structure and corrosion behavior of K_2Ti_6O_(13)/TiO_2 composite coating prepared by electrochemical method

作　　者：刘倩楠[1] 刘咏[1] 吴宏[1] 罗涛[1] 汤慧萍[2] 

机构地区：[1]中南大学粉末冶金国家重点实验室,长沙410083 [2]西北有色金属研究院多孔材料国家重点实验室,西安710016

出　　处：《粉末冶金材料科学与工程》2014年第4期538-545,共8页Materials Science and Engineering of Powder Metallurgy

基　　金：国家自然科学基金面上项目(51272289);国家高技术研究发展计划(863项目)(2013AA031103)

摘　　要：采用电化学两步反应在纯钛基体表面制备K2Ti6O13/TiO2复合涂层,对其形貌、相组成和电化学耐腐蚀性能进行研究,并与传统化学方法制备的涂层进行比较。结果表明,电化学法制备的涂层为多孔网状结构,由内层阻碍层和外层多孔层的双层膜组成,可抑制Ti基体过钝化时的O2析出;KOH电解液作用时,随电流密度增加,涂层阻抗值减小,多孔层厚度逐渐增加;电流密度大于20 mA/cm2时,涂层发生脱落,但其耐腐蚀性能仍高于化学方法制备的涂层。因此通过电化学方法制备的涂层可改善Ti基体的腐蚀行为,使其具有更优异的耐腐蚀性能。The K2Ti6O13/TiO2 coatings were prepared on pure titanium substrate by electrochemical two-step reaction. The morphologies, phase composition and electrochemical corrosion resistance properties of the coatings were studied and compared with the coating prepared by traditional chemical treatment. The results show that the coatings exhibiting porous network structure are composed of inner barrier layer and outer porous layer, and can inhibit the release of O2 in the process of trans-passivation of Ti substrate; during the treatment of KOH electrolyte, both the impedance of coatings and the thickness of porous layer increase with increasing current density; the coating peels off at current density above 20 mA/cm^2, however, the corrosion resistance property is still higher than that of coating prepared by chemical treatment. Thus, the coatings prepared by electrochemical method can improve the corrosion behavior of Ti substrate, providing it more stable corrosion resistance property.

关 键 词：Ti基体 网状涂层 极化曲线 电化学阻抗谱 耐腐蚀性 

分 类 号：TG174.41[金属学及工艺—金属表面处理]