锌液中微量Mg对热镀锌层形貌、组织和耐蚀性的影响  

Influence of a Small Amount of Magnesium Added In Hot-Dip Galvanizing Solution on Microstructure and Corrosion Resistance of Galvanizing Coatings

作　　者：王贺贺 唐囡[2] 江社明 李远鹏 杨佑华 俞钢强 

机构地区：[1]中国钢研科技集团有限公司先进金属材料涂镀国家工程实验室,北京100081 [2]国网江西省电力科学研究院,江西南昌330096 [3]江西省电力公司,江西南昌330096

出　　处：《材料保护》2015年第4期56-58,9,共3页Materials Protection

基　　金：国家电网科技项目(521820130014)资助

摘　　要：目前关于在热镀锌液中添加微量Mg对合金镀层组织结构及耐蚀性影响的报道较少。采用Mg含量分别为0.05%,0.10%,0.30%的锌基合金在低碳钢退火板上热镀锌。利用扫描电镜及能谱仪分析镀层的表面形貌、组织结构及成分,并对镀层进行中性盐雾试验,研究了锌液中微量Mg对镀层的形貌、组织结构及耐蚀性的影响。结果表明:锌液中添加微量Mg可明显细化镀层晶粒,使晶粒尺寸减小,锌液中Mg含量从0.05%增加至0.30%,镀层晶粒尺寸不断变小;添加微量Mg不影响镀层主体结构,但会细化各金属间化合物的晶粒,提高了镀层的耐蚀性,Mg含量升高,镀层耐蚀性增强。A small amount of Mg(mass fraction:0.05%,0.10%and 0.30%) was introduced into hot-dip galvanizing solution to prepare galvanizing coatings on annealed low carbon steel substrate.The morphology,microstructure and composition of as-prepared hot-dip galvanizing coatings were analyzed by scanning electron microscopy and energy dispersive spectrometry,and their corrosion resistance was evaluated with neutral salt-spray tests.Furthermore,the influence of the low concentration of Mg added in the hot-dip galvanizing solution on the microstructure and corrosion resistance of the galvanizing coatings was investigated.It was found that introducing a small amount of Mg into the hot-dip galvanizing solution helped to refine the grains of the galvanizing coatings and reduce the size of the grains.When the content of Mg in the hot- dip galvanizing solution increased from0.05%to 0.30%,the grain size of the galvanizing coatings continuously rose.In the meantime,the introduction of a small amount of Mg into the hot-dip galvanizing solution did not influence the microstructure of the galvanizing coatings but caused refining of the grains of various intermetallic compounds and improved the corrosion resistance of the coatings.Moreover,the corrosion resistance of the hot-dip galvanizing coatings tended to rise with increasing concentration of Mg in the galvanizing solution.

关 键 词：热镀锌 微量Mg 锌基合金 组织结构 形貌 耐蚀性 

分 类 号：TG174.44[金属学及工艺—金属表面处理]