MED EN ZINK-ALUMINIUMLEGERING GENOM VARMDOPPNING BELAGD STAOLPLAOT, FOERFARANDE FOER FRAMSTAELLNING AV EN MAOLAD STAOLPLAOT OCH MEDELST FOERFARANDET FRAMSTAELLD MAOLAD STAOLPLAOT.

摘要

A hot-dip zinc-aluminum alloy coated steel sheet produced by coating in a hot dipping bath comprising 0.3 to 3.5 wt.% of Al, 100 ppm or less of Pb and the balance of Zn and unavoidable impurities is provided. The bath may further contain specified amounts of Si as well as Mg, Mn and/or Cu. A process for producing said coated steel sheet is also provided, wherein the temperature of the steel sheet to be dipped into the hot dipping bath is adjusted to be lower than the bath temperature and, if necessary, the amount of the molten zinc-aluminum alloy deposited on the steel sheet is controlled with a special gas wiping type of equipment and, if necessary, the coated steel sheet is reheated at a temperature higher than the melting temperature of the coating layer. A prepainted steel sheet prepared from this steel sheet is also provided.