高强度紧固件用涂层的耐蚀性  

Corrosion Resistance of Coatings for High-Strength Fastening Parts

作　　者：刘鹏 江社明[1] 李远鹏[1] 高志强 张启富[1] LIU Peng;JIANG Sheming;LI Yuanpeng;GAO Zhiqiang;ZHANG Qifu(National Engineering Laboratory of Advanced Coating Technology for Metal,Central Iron and Steel Research Institute,Beijing 100081,China;Corrosion and Protection Center,University of Science and Technology Beijing,Beijing 100083,China)

机构地区：[1]钢铁研究总院先进金属材料涂镀国家工程实验室,北京100081 [2]北京科技大学腐蚀与防护中心,北京100083

出　　处：《腐蚀与防护》2019年第12期886-892,897,共8页Corrosion & Protection

基　　金：十三五国家重点研发计划(2017YFB0304305)。

摘　　要：在高强度紧固件用钢基体上制备了渗锌、渗锌-硅酸盐封闭、渗锌-达克罗-含铝封闭三种耐蚀涂层。使用扫描电子显微镜(SEM)以及能谱仪(EDS)分析中性盐雾试验前后涂层形貌及成分变化,讨论涂层的腐蚀特征;使用电化学阻抗法和电化学极化法分析了涂层的电化学特征。结果表明:与渗锌涂层相比,渗锌-硅酸盐封闭、渗锌-达克罗-含铝封闭涂层具有更优异的耐蚀性,其中渗锌-达克罗-含铝封闭涂层的耐蚀性最佳;在腐蚀过程中,渗锌涂层的腐蚀形式主要为渗锌层的应力腐蚀,渗锌-硅酸盐封闭涂层的腐蚀形式主要为封闭层的点蚀与全面腐蚀,渗锌-达克罗-含铝封闭涂层则出现封闭层的剥离。Three kinds of corrosion resistant coatings,zinc pack coating,zinc pack coating with silicate sealing and zinc pack coating with both Dacromet and aluminiferous sealing,were prepared on the substrate of steel for highstrength fasteners.The differences of morphology and element content before and after neutral salt spray test were investigated to analyze the corrosion characteristics of coatings by scanning electron microscopy(SEM)and energy dispersive spectroscopy(EDS).Electrochemical characteristics were also investigated by electrochemical impedance spectroscopy and electrochemical polarization.The results show that the zinc pack coating with silicate sealing and the zinc pack coating with both Dacromet and aluminiferous sealing had much better corrosion resistance than zinc pack coating,and the corrosion resistance of the zinc pack coating with both Dacromet and aluminiferous sealing was the best in three kinds of coatings.During corrosion process,the main corrosion mode of the zinc pack coating was stress corrosion of the zinc coating layer,and the main corrosion modes of the zinc pack coating with silicate sealing were both general corrosion and pitting corrosion of the sealing layer.For the zinc pack coating with both Dacromet and aluminiferous sealing,peeling effect between sealing layer and Dacromet layer was observed.

关 键 词：紧固件 渗锌 封闭 达克罗 耐蚀性 

分 类 号：TG174[金属学及工艺—金属表面处理]