1992-02-01

Effect of Coating Structure on Powdering Resistance of Galvannealed Steel Sheet 920174

Galvannealed steel sheets containing 10wt%Fe in coated layer were prepared in various galvannealing temperature and cooling rate. Powdering resistances were evaluated by a draw bead test. X-ray diffraction examination revealed an attribution of the coating structure to powdering resistance.
Higher galvannealing temperature(500∼550°C) deteriorates powdering resistance, but slower cooling from higher temperature improves it. At low galvannealing temperature(440°C), powdering resistance is rather good independent of cooling rate. Г1-phase(Fe5Zn21) is formed along the interface between coating and steel when samples are galvannealed at lower temperature(≦500°C) or cooled at slower cooling rate from higher galvannealing temperature. The results suggest that the increase of Г1 ratio [Г1/(Г+Г1)] in the coating is inclined to improve powdering resistance.

SAE MOBILUS

Subscribers can view annotate, and download all of SAE's content. Learn More »

Access SAE MOBILUS »

Members save up to 18% off list price.
Login to see discount.
Special Offer: Download multiple Technical Papers each year? TechSelect is a cost-effective subscription option to select and download 12-100 full-text Technical Papers per year. Find more information here.
We also recommend:
TECHNICAL PAPER

The Peeling-Off Resistance of Zinc and Iron-Zinc Coated Steel Sheets in Stamping

890349

View Details

TECHNICAL PAPER

Influence of Strain State on Powdering of Galvannealed Sheet Steel

960026

View Details

TECHNICAL PAPER

Correlation of Prephosphate Treatment, Surface Friction and Powdering of Galvanneal During Forming

980075

View Details

X