Heat Resistance of Hot-dipped 55%Al-Zn Steel Sheet

The hot-dipped 55%Al-Zn steel sheet was baked at 300,350,400,450℃, respectively, and the changes of the gloss, mass per unit area, morphology, chemical composition and bonding performance of the hot-dipped aluminum zinc steel sheet baked for 24 h at different temperatures were studied. The heat resistance of the steel sheet was analyzed. The results show that the performance of the plating did not change after baking at 350℃ or below for 24 h. When baked at 400℃ for 24 h, the gloss of the plating declined slightly, the cracks appeared on the surface, but the surface morphology, chemical composition, mass per unit area and bonding performance changed little. When baked at 450℃ for 24 h, the gloss and mass per unit area of the plating decreased obviously, the bonding performance got worse, and part of the plating flaked off.