锌铝镁板表面硫脲改性水性丙烯酸树脂-有机硅烷复合钝化膜的耐蚀性能研究  

Corrosion Resistance of Thiourea-Modified Waterborne Acrylic Resin Organic Silane Composite Passivation Film on the Surface of Zn-Al-Mg Plate

作　　者：马常帅 冉长荣 伏建康[1] 王运厚 郭太雄 张千峰[1] MA Changshuai;RAN Changrong;FU Jiangkang;WANG Yunhou;GUO Taixiong;ZHANG Qianfeng(Institute of Molecular Engineering and Applied Chemistry,Anhui University of Technology,Ma’anshan 243002,China;PanGang Group Research Institute Co.,Ltd.,State Key Laboratory of Vanadium and Titanium Resources Comprehensive Utilization,Panzhihua 617000,China)

机构地区：[1]安徽工业大学分子工程与应用化学研究所,安徽马鞍山243002 [2]攀钢集团研究院有限公司钒钛资源综合利用国家重点实验室,四川攀枝花617000

出　　处：《材料保护》2024年第6期43-51,共9页Materials Protection

基　　金：校企产学研联合科技攻关项目(MS2013019)资助。

摘　　要：为探究硫脲改性水性丙烯酸树脂-有机硅烷复合钝化膜对锌铝镁镀层耐蚀性能的影响,以水性丙烯酸树脂-有机硅烷作为主要成膜物质,添加不同含量的硫脲复配出无铬钝化液,对锌铝镁镀层进行复合钝化。采用Nano ZS90型纳米粒度仪测试硫脲的粒径大小,采用Nicolet 6700型傅立叶红外光谱仪(FTIR)测试硫脲的结构,通过全浸试验、电化学测试和中性盐雾试验,分析复合钝化膜的耐蚀性能,并探究了硫脲含量对复合钝化膜腐蚀速率的影响。结果表明:硫脲对锌铝镁镀层的耐蚀性起到了缓蚀作用,但是硫脲含量过多,会使钝化膜的缓蚀性下降,对比了3种不同硫脲添加量,当钝化液中硫脲的质量分数为0.5%时,锌铝镁镀层的耐蚀性最优。硫脲与水性丙烯树脂-有机硅烷发生了交联作用,腐蚀后与金属形成配合物,形成了致密的网状结构,提高了膜层的致密性,从而降低了膜层的腐蚀速率。For exploring the effect of thiourea on the corrosion resistance of waterborne acrylic resin organic silane composite passivation film on Zn-Al-Mg coating,an aqueous acrylic resin-organosilane was used as the main film-forming material,and different contents of thiourea were added to formulate a chromium-free passivate solution for the composite passivation of Zn-Al-Mg coatings.The particle size of thiourea was measured by Nano ZS90 nanoparticle size analyzer,and the structure of thiourea was tested by Nicolet 6700 Fourier transform infrared spectrometer(FTIR).In addition,the corrosion resistance of the composite passivation film was analyzed through full immersion test,electrochemical test and neutral salt spray test,and the effect of thiourea content on the corrosion rate of the composite passivation film was explored.Results showed that thiourea possessed an inhibitory effect on the corrosion resistance of Zn-Al-Mg coatings,but too much thiourea could lead to a decrease in the corrosion inhibition of the passivation film.Compared with three different addition amounts of thiourea,the corrosion resistance of the Zn-Al-Mg coating was optimal when the mass fraction of thiourea in the passivation solution was 0.5%.Furthermore,thiourea and waterborne acrylic resin organic silane underwent cross-linking,and after corrosion,they formed a complex with metals,forming a dense network structure,which improved the density of the film layer and reduced the corrosion rate of the film layer.

关 键 词：硫脲 锌铝镁镀层 钝化膜 电化学 中性盐雾试验 耐蚀性 

分 类 号：TG174.4[金属学及工艺—金属表面处理]