Production of plated steel stock excellent in adhesion

Abstract

Abstract PURPOSE:To produce a plated steel sheet capable of keeping excellent corrosion resistance by forming a plated layer vapor-deposited with Al having specified thickness on steel stock preheated at specified temp. and thereafter lowering preheating temp. and forming the plated layer vapor-deposited with Zn or Zn-Al alloy thereon. CONSTITUTION:A steel sheet having a cleaned surface is preheated at 200-350 deg.C in the nonoxidizing atmosphere and then a plated layer vapor-deposited with Al having 0.1-2mu thickness is formed thereon. Thereafter the temp. of this steel sheet is adjusted at 150-200 deg.C and the plated layer vapor-deposited with Zn or Zn-All alloy is formed thereon. In this method, adhesion of the layer vapor-deposited with Al for the steel sheet is not sufficiently insured at preheating temps. lower than 200 deg.C and on the other hand, the properties of the steel stock are changed at the temps. higher than 350 deg.C and furthermore adhesion of the layer vapor-deposited with Al is deteriorated. Further sufficient adhesion is not obtained at thickness smaller than 0.1mu of the layer vapor-deposited with Al and effect for improving adhesion is not enhanced more than it even at thickness larger than 2mu. Adjustment of the temp. of the steel sheet at a time for forming the Zn-base vapor-deposited layer is performed to prevent a state of vapor deposition from being made unstable because once vapor- deposited Zn is again vapor-deposited.

Inventors

• 👤 Kazutoshi Shimogoori
• 👤 Hiroshi Sato
• 👤 Masao Toyama
• 👤 Hidetoshi Nishimoto
• 👤 Tsugumoto Ikeda
• 👤 Jiyunji Kawafuku

Bibliographic Details