植酸/硅烷复合钝化镀锌层的耐蚀性能  

Corrosion Resistance of Composite Galvanized Film with Composite Passivation of Phytic Acid/Silane

作　　者：贲建栋 鲁钢[1] 孙大东[1] 

机构地区：[1]南京工业大学材料科学与工程学院,江苏南京210000

出　　处：《材料保护》2015年第10期13-15,7,共3页Materials Protection

基　　金：江苏高校优势学科建设工程项目

摘　　要：为了提高镀锌钢的耐蚀性,先用植酸进行钝化,再用硅烷进行钝化,形成复合钝化膜。通过硫酸铜点滴、碱浸失重和EIS阻抗法研究了复合钝化膜的耐蚀性及其耐蚀机理;通过红外光谱及SEM分析了复合钝化膜的形貌及结构。结果表明:复合钝化膜有更好的耐蚀性,碱浸失重速率低于单一钝化膜,自腐蚀电流密度下降2个数量级,达到3.142×10-8A/cm2;复合钝化膜结构紧密,抑制了电子与Zn2+在金属界面与腐蚀介质间的扩散和转移,阻碍了电化学腐蚀中的阴极还原反应,降低了镀锌层的腐蚀速率。For enhancing corrosion resistance,the galvanized steel was passivized first by phytic acid,then by silane.The drip test,weight lost test in alkali solution and electrochemical impendence spectra(EIS) were used to study the corrosion resistance and anticorrosion mechanism of the composite passive film.The morphology and structure of composite film were investigated by infrared spectrum and scanning electron microscope(SEM).Results showed that the composite passive film had more excellent corrosion resistance than the single passive film.The mass loss rate of the composite film was lower than that of single film,and the self-corrosion current density was 3.142×10^(-8) A/cm^2,which was decreased by two orders of magnitude.Furthermore,due to the compact structure of the composite film,the diffusion and transition of electrons and Zn^(2+) ions from metallic interface to corrosive medium were inhibited,which blocked the cathode reduction reaction of electrochemical corrosion and reduced the corrosion rate of galvanized layer.

关 键 词：复合钝化 植酸与硅烷 镀锌层 耐蚀性 

分 类 号：TG174.443[金属学及工艺—金属表面处理]