8-羟基喹啉对提高LY12铝合金钒/锆转化膜耐蚀性的作用  

Modification of 8- Hydroxyquinoline for Improving the Corrosion Resistance of V/Zr Conversion Coating on LY12 Al Alloy

作　　者：何蕾[1] 郭瑞光[1] 李海燕[1] 

机构地区：[1]西安建筑科技大学西北水资源与环境生态教育部重点实验室,陕西西安710055

出　　处：《材料保护》2015年第7期6-10,共5页Materials Protection

基　　金：国家自然科学基金项目(209761403);教育部高等学校博士学科点专项科研基金(20096120110007)资助

摘　　要：为了提高LY12铝合金表面钒/锆转化膜的耐蚀性,采用单因素试验对钒/锆转化膜进行8-羟基喹啉耐蚀改性研究。采用扫描电镜(SEM)、能谱分析(EDS)、X射线光电子能谱(XPS)、傅里叶变换红外光谱(FTIR)分析了改性后转化膜的形貌及成分,采用中性盐雾(NSS)和电化学测试研究了其耐蚀性能。结果表明:采用0.1 g/L8-羟基喹啉,4.0 g/L偏钒酸钠,2.5 g/L氟锆酸钾为转化液,在p H值为4.0,温度70℃下转化35 min,LY12铝合金表面便形成了钒、锆氧化物及8-羟基喹啉薄层转化膜,使得铝合金腐蚀电位较改性前正移了41 m V,腐蚀电流密度减小了79.7%,盐雾时间由改性前的24 h增加至改性后的72 h,其耐蚀性能大幅度提高。In order to enhance the corrosion resistance of the V/Zr conversion coating on LY12 Al alloy,the V / Zr conversion coating was modified by 8-hydroxyquinoline through single factor experiment. The morphology and composition of the conversion coating were analyzed by scanning electron microscopy( SEM),energy dispersive spectrometer( EDS),X-ray photoelectron spectroscopy( XPS) and Fourier transform infrared spectrum( FTIR). The corrosion resistance of the coating was evaluated by neutral salt spray test( NSS) and polarization curve measurement. Results showed that the thin coating of V,Zr oxides and 8-hydroxyquinoline on LY12 Al alloy was obtained under the condition of 0. 1g / L 8-hydroxyquinoline,4. 0 g/LNaVO3,2. 5 g/L K2 ZrF 6,pH = 4. 0,70 ℃ and 35 min. The coating led to the increase of corrosion potential of the sample by 41 mV,the decrease of corro-sion current density by 79. 7%,and the increase of salt spray time from 24 h to 72 h,which indicated that the corrosion resistance of Al alloy was significantly improved.

关 键 词：钒/锆转化膜 LY12铝合金 8-羟基喹啉改性 耐蚀性 

分 类 号：TG174.4[金属学及工艺—金属表面处理]