镀锌C-Mn-Al-Mo系双相高强钢盐雾腐蚀行为研究

Study on Salt-spray Corrosion Behavior of Galvanized C-Mn-Al-Mo Dual-phase High Strength Steel

通过盐雾腐蚀箱试验和扫描电镜研究了不同沉降量、不同盐雾时间对含铝双相高强钢失重速率和腐蚀行为的影响。试验结果表明:在不同的沉降量下,板材的腐蚀速率不同。随着沉降量的增加,钢板失重增加;随着盐雾时间的延长,腐蚀产物覆盖在镀锌板表面,阻碍了纯锌层与腐蚀液的接触,减缓了腐蚀的进行。由于双相钢中Mn元素等容易在表面聚集,造成纯锌层与基板的粘附性变差,在通过36h盐雾腐蚀后,带钢表面产生红锈的面积达到了75%。通过显微组织观察,腐蚀产物的形貌呈雪花状,主要成分是Fe3O4。

The effects of different deposition amount and different salt spray time on the weight loss rate and corrosion behavior of aluminum-containing dual-phase high strength steel are studied by salt spray corrosion chamber test and scanning electron microscope (SEM). The experimental results show that the corrosion rate of the plate is different under different sedimentation amount. With the increase of deposition, the weight loss of steel plate increases, and the corrosion product is covered on the surface of galvanized sheet with the prolongation of salt spray time, which hinders the contact between pure zinc layer and corrosion solution, and slows the corrosion process. Because Mn elements in dual-phase steel are easy to aggregate on the surface, the adhesion of the pure zinc layer to the substrate becomes worse. After 36 hours of salt spray corrosion, the area of red rust on the surface of the strip is up to 75%. According to the microstructure observation, the morphology of the corrosion product is snowflake, and the main component is Fe3O4.