热浸镀铝硅合金镀层的锈蚀过程

Corrosion Behavior of Hot-dip Al-Si Alloy Plate

研究了热浸镀铝硅合金钢板在动态接触湿热试验过程中不同阶段的锈蚀行为,采用扫描电镜(SEM)、能谱仪(EDS)分析了铝硅合金镀层锈蚀过程中的表面形貌、成分及组织结构变化。结果表明:热浸镀铝硅合金镀层的锈蚀过程是一个整体有序的演变过程,钢板锈蚀过程的表面形貌随暴露时间增长呈坑蚀-环蚀-面蚀变化规律;暴露时间越长,锈蚀程度越强,锈蚀产物中的氧含量越高;热浸镀铝硅合金镀层的初始锈蚀发生在富硅相(硅含量15%以上)和晶粒间的交界处(多为富铝相硅含量5%以下)。

The corrosion behavior of hot-dipped Al-Si alloy plate at different stages of the dynamic damp heat test was studied. The morphology, elements and structures of the hot-dipped Al-Si alloy plate in corrosion process were analyzed by SEM and EDS. The results showed that the corrosion process of the hot-dipped Al-Si alloy plate was a whole evolution process in an orderly manner. The change rule of the surface morphology obeyed the variation of pitting corrosion-round corrosion-flake corrosion with the increase of exposure time. The longer the exposure time, the stronger the corrosion degree, and the higher the oxygen content of the corrosion products. The corrosion of the hot-dipped Al-Si alloy was initiated with rich Si point （Si〉15%） and intergranular rich A1 point （Si〈5%）.