热浸镀后的冷却速率对低碳钢薄板镀层锌花尺寸和形态的影响  

Effect of Cooling Rate after Hot-dip Plating on Size and Form of Spangle in Coating on Mildsteel Sheet

作　　者：韩治辉 王保磊 王华[1] HAN Zhihui;WANG Baolei;WANG Hua(Instrumental Analysis & Research Center, Shanghai University, Shanghai 200444, China)

机构地区：[1]上海大学分析测试中心,上海200444

出　　处：《上海金属》2021年第5期14-20,26,共8页Shanghai Metals

基　　金：国家重点研发计划(No.2017YFB0304402)。

摘　　要：采用热浸镀模拟器对低碳钢薄板进行了热浸镀铝锌硅,并在镀后540~430℃温度范围内以不同的速率冷却。采用光学显微镜(OM)、扫描电子显微镜(SEM)和能谱仪(EDS)检测了镀层的表面和截面形貌及成分。探讨了镀层凝固过程中锌花的形成机制。结果表明:在16~28℃/s的冷却速率范围内,随着冷速的提高,锌花尺寸减小,组织细化,二次枝晶间距减小,化合物层减薄。当冷却速率从19℃/s提高至23℃/s时,锌花尺寸从2 mm减小至1.2 mm。Aluminum-zinc-silicon coating was fabricated on the mildsteel sheet by means of a hot-dip plating simulator,and then the sheet was cooled at different rates within the range of 540 to 430℃.The surface and cross-section morphology and composition of the coating were detected by using optical microscope(OM),scanning electron microscope(SEM)and energy dispersive spectrometer(EDS).The mechanism whereby spangle formed in the coating during solidification was discussed.The results showed that as the cooling rate was increased from 16 to 28℃/s,the spangle size became smaller,the structure became finer,the secondary dendrite spacing became smaller,and the compound layer thickness decreased.As the cooling rate was increased from 19 to 23℃/s,the spangle size reduced from 2 to 1.2 mm.

关 键 词：低碳钢薄板 冷却速率 锌花尺寸 铝锌硅镀层 

分 类 号：TG174.443[金属学及工艺—金属表面处理]