植酸-钒酸盐复合转化膜的制备及其耐腐蚀性能研究  

Preparation and Corrosion Resistance of Phytic Acid-Vanadate Composite Conversion Coatings

作　　者：卢勇[1,2] 冯辉霞[1] 杨吉斌[1] LU Yong;FENG Hui-xia;YANG Ji-bin(School of Petrochemical Engineering,Lanzhou University of Technology,Lanzhou 730050,China;Research Institute of Lanzhou Petrochemical Corporation of PetroChina,Lanzhou 730060,China)

机构地区：[1]兰州理工大学石油化工学院,甘肃兰州730050 [2]中国石油兰州石化公司研究院,甘肃兰州730060

出　　处：《材料保护》2020年第6期77-82,共6页Materials Protection

基　　金：国家科技部“科技人员服务企业行动项目”(2009GJG10041);甘肃省高校基本科研业务费(1105ZTC136)资助。

摘　　要：植酸具有在钢铁表面形成转化膜的潜力,可以延缓腐蚀速度。但植酸涂层中松散的结构和微裂纹会破坏涂层的紧密性,裂纹为腐蚀性介质传递提供有效通道,严重削弱膜层的保护作用。用钒酸盐转化液对植酸膜层进行后处理用于膜层致密化,提高转化膜对钢铁的防腐蚀效果。采用扫描电子显微镜观察转化膜的微观形貌,用能谱仪测定不同样品膜层的元素组成,并用X射线光电子能谱测定膜层元素化学价态。结果表明:植酸同钒酸盐复合后形成了致密均匀的转化膜。相比于裸钢和植酸涂层,复合转化膜层使钢具有最小的腐蚀电流密度和腐蚀速率,其保护效率高达94.3%。Phytic acid has potential to synthesize a conversion coating on metal surface for retarding corrosion.However,the loose structureand micro-cracks in the phytic acid coating layer damaged the tightness of coating,which provided efficient channels for corrosive medium andseriously weakened the protective effect of coating.In this work,the phytic acid coated steel was post-treated with vanadate conversion bath forenhancing the coating densification,and thus the anti-corrosion protection effect of conversion coating on metal was improved.Moreover,themicro-morphology,element composition and elemental chemical states of coatings were observed by scanning electron microscopy,X-rayenergy dispersive spectrum and X-ray photoelectron spectroscopy,respectively.Results showed that after co-treated by phytic acid andvanadate compound,the dense and uniform conversion coatings were prepared.Compared with bare steel and phytic acid coating,the compositeconversion coating had the minimum corrosion current density and corrosion rate,the protection efficiency of which was up to 94.3%.

关 键 词：钢铁 植酸-钒酸盐复合 转化膜 耐腐蚀 

分 类 号：TG174.44[金属学及工艺—金属表面处理]