Hot-dip galvanizing process and coating corrosion behavior of fe-mn-al-c steel

Abstract

The temperature of the zinc bath and the immersion duration are critical factors that significantly impact the surface quality and adhesion of batch hot-dip galvanizing coatings. This study focuses on the influence of different zinc bath temperatures (460, 490, and 520 °C) and immersion duration (1, 3, 5, and 10 min) on the hot-dip galvanized coatings of Fe-Mn-Al-C lightweight steel, which were characterized using scanning electron microscopy and energy dispersive X-ray analysis. The results demonstrate that with the increasing zinc bath temperature and immersion duration, the coating thickness and bond strength initially increase and then decrease. The inhibition layer in the coating gradually fractures and thickens with the rising temperature, leading to changes in the alloy phases within the coating. The optimal batch hot-dip galvanizing condition for the experimental steel is immersing at 490 °C for 3 min. Furthermore, we conducted a neutral salt spray corrosion test on the specimens under the optimal batch hot-dip galvanizing condition to study their corrosion behavior and mechanism and evaluate the impact of batch hot-dip galvanizing on the corrosion resistance of Fe-Mn-Al-C steel.