【摘要】 研究热镀铝锌合金镀层剖面上的元素组成和电化学性能，探究腐蚀过程，解析镀层性能对产品的耐腐蚀性能影响。通过盐酸溶解时间制备不同深度剖面的镀层，结合金相、辉光分析、能谱分析、SEM和电化学测试等手段，分析热镀铝锌镀层剖面结构组成、电化学性能和腐蚀过程。研究发现铝锌镀层表面以富铝相作为骨架，富锌相构成锌花外观网络，在镀层深度剖面方向上，存在锌花枝晶结构和冷却微孔通道，逐层电位从-1.04 V上升至-0.70 V;镀层深度剖面上，Al、Zn等元素含量分布不同，Si元素以高含量均匀存在于中间镀层，O元素仅存在于镀层浅表面0.1μm;电化学测试表明，镀层在剖面上存在耐蚀性能的差异，其耐蚀性能顺序为：浅表层>合金层>中间镀层。推断得出腐蚀过程为浅表层被腐蚀后，其腐蚀趋势沿中间镀层深度方向发展，达到合金层时，腐蚀趋势不再向深度进行，转而沿合金层与中间镀层界面发生。综上，可以明确铝锌镀层为非均相合金镀层，其镀层元素成分不均匀、高温冷却产生浅表层氧化膜层，以及合金层中高Si金属间化合物造成了镀层逐层电化学耐蚀性差异。更多还原

【Abstract】 To study the elemental composition and electrochemical properties of hot-dip aluminum-zinc coating profiles and investigate the corrosion process. Different depth profiles of the coating were prepared by hydrochloric acid dissolution time, combined with metallography, spark analysis, energy spectrum analysis, SEM, and electrochemical tests, to analyze the profile structure, composition, electrochemical properties, and corrosion process of the hot-dip aluminum-zinc coating. In the depth profile direction of the coating, the content of elements such as Al and Zn varies, the potential rises from-1.04 V to-0.70 V, dividing the coating into surface layer, intermediate layer, and alloy layer. Electrochemical tests show that there are differences in corrosion resistance performance on the profile of the coating, with the corrosion resistance performance order being: surface layer > alloy layer > intermediate layer. It is inferred that the corrosion process starts with the surface layer being corroded, and the corrosion trend develops along the depth direction of the intermediate layer. When reaching the alloy layer, the corrosion trend no longer progresses in depth, and occurs along the intermediate layer interface. Above all, it can be conclude that the Al-Zn coating is a heterogeneous alloy coating, the uneven composition of the coating elements, the formation of an shallow surface oxide film on the surface due to high-temperature cooling, and the formation of intermetallic compounds of high Si in the alloy layer result in differences in the electrochemical corrosion resistance of the coating layer by layer.更多还原