The Optimization of the Inhibition Layer to Obtain Compact Surfaces of the Galvannealed Steel Sheets during Galvannealing Processes

摘要

Galvanizing simulations were performed at different conditions of Final Cooling Section(FCS) temperatures with 480, 515, 530 and 560 deg C. The tested samples gave the different morphologies and amounts of the inhibition layers comprised of Fe-Al intermetallic compounds formed at the coating/substrate interfaces. The compactness of the inhibition layers was assessed, and the sample A2 with the FCS temperature of 515 deg C has formed a very fine and compact inhibition layer. These galvanized specimens were galvannealed at 500 deg C for 22 seconds by using a Rhesca hot dipping system, and sample A2 containing the most fine and compact inhibition layer produced the very sound galvanneal surface. For more precise galvanneal investigations, Gleeble system was utilized with XRD, and SEM/EDS analyses.