Manufacture of steel plate coated with alloyed zinc by galvanization

Abstract

Abstract PURPOSE:To uniformalize the thickness of each of layers formed by galvanization and to enhance the surface appearance, corrosion resistance and weldability, by dipping a steel plate in a Zn bath contg. specified amounts of Al, Mg and Pb to carry out galvanization at a specified temp., introducing the plate into a heating furnance when the resulting layers are in a melted or half-melted state, and heating the plate under specified conditions. CONSTITUTION:A steel plate is dipped in a Zn bath consisting of, by weight, 0.3-5% Al, 0.01-2% Mg, <0.01% Pb and the balance Zn with inevitable impurities to carry out galvanization at 450-480 deg.C bath temp., and the thickness of each of the resulting layers is adjusted to <=30g/m<2> by a gas blowing method. When the layers are in a melted or half-melted state, the plate is introduced into a heating furnace kept at 550-1,200 deg.C atmospheric temp., and it is heated for 2-30sec to accelerate the mutual diffusion of Fe in the plate and Zn in the layers. By the diffusion the layers are partially alloyed.

Inventors

• 👤 Takehiko Ito
• 👤 武彦 伊藤
• 👤 Kiichiro Katayama
• 👤 片山　喜一郎
• 👤 Fumihiro Ida
• 👤 井田　文博
• 👤 Yorimasa Mitani
• 👤 美谷　頼政
• 👤 Yasushi Mitsuyoshi
• 👤 泰史 三吉
• 👤 Toshio Yoshimoto
• 👤 吉本　利夫

Bibliographic Details