热浸超低镍含量Zn-Ni合金镀层的组织与性能研究  

Study on microstructure and properties of hot-dip ultra-low nickel content Zn-Ni alloy coating

作　　者：章平 王胜民[1] 王志斌 邱文利 苗杨 何飞 ZHANG Ping;WANG Shengmin;WANG Zhibin;QIU Wenli;MIAO Yang;HE Fei(Faculty of Material Science and Engineering,Kunming University of Science and Technology,Kunming 6500931,China;Hebei Xiong'an Jingde Expressway Co.,LTD.,Xiong'an 071700,China)

机构地区：[1]昆明理工大学材料科学与工程学院,昆明6500932 [2]河北雄安京德高速公路有限公司,河北雄安071700

出　　处：《材料科学与工艺》2025年第1期41-48,共8页Materials Science and Technology

摘　　要：探究450℃下于Q345钢基体表面制备的锌镍镀层(浸镀5、10、30、60、120 s)的组织特征和耐腐蚀性能,并与纯锌镀层对比从而研究镀层中镍的作用机理。采用扫描电镜(SEM)和能谱仪(EDS)观察分析镀层的组织结构,采用电化学极化法、中性盐雾加速腐蚀、全浸实验测试分析了镀层的动电位极化曲线、耐盐雾腐蚀和耐盐水浸泡性能,采用XRD分析了镀层盐雾实验200 h时的白锈产物。结果表明:在10 s内,Ni含量为0.045wt.%的锌镍合金锌浴对镀层ζ相有明显的抑制作用,ζ相更致密,厚度较纯锌镀层明显减薄;在浸镀120 s时,对ζ相的抑制作用更明显。锌镍合金锌浴制备的镀层厚度变薄,耐电化学腐蚀性能、耐中性盐雾腐蚀能力和耐盐水浸泡性能较好,中性盐雾实验200 h产生的白锈较少,白锈产物与纯锌镀层的腐蚀产物成分相同,均为Zn_(5)(OH)_(8)Cl_(2)H_(2)O、Zn_(4)(CO_(3))(OH)_(6)H_(2)O。In order to investigate the mechanism of nickel action in the coating,this study explores the microstructure and corrosion resistance of zinc nickel coating(dipping for 5,10,30,60,120 s)prepared on Q345 steel substrate at 450℃,and compares with that of pure zinc coating.Firstly,the microstructure of the coating was observed and analyzed by SEM and EDS.Secondly,the potentiodynamic polarization curve,salt spray corrosion resistance and salt water immersion resistance of the coating were analyzed by electrochemical polarization method,neutral salt spray accelerated corrosion and full immersion test.Thirdly,the white rust products were analyzed by XRD after 200 h salt spray test.The results showed that the Zn-Ni alloy zinc bath with Ni content of 0.045wt.%has an obvious inhibitory effect on the phase of the coating within 10 s,and the phase is denser and thinner than that of the pure zinc coating.Furthermore,the inhibition effect on phase is more obvious at 120 s.The coating prepared by zinc bath of Zinc-Ni alloy has thinner thickness,better electrochemical corrosion resistance,neutral salt spray corrosion resistance and salt water immersion resistance.In addition,neutral salt spray test produced less white rust after 200 h.The composition of the white rust products are Zn_(5)(OH)_(8)Cl_(2)H_(2)O and Zn_(4)(CO_(3))(OH)_(6)H_(2)O,which is the same as that of the corrosion products of pure zinc coating.

关 键 词：锌镍合金 热浸镀 镀层组织 耐蚀性能 盐雾实验 

分 类 号：TG174.4[金属学及工艺—金属表面处理]