Title:
PRODUCTION OF GALVANIZED STEEL SHEET EXCELLENT IN SPOT WELDABILITY
Document Type and Number:
Japanese Patent JPH03264687
Kind Code:
A
Abstract:
PURPOSE:To obtain a galvanized steel sheet which is excellent in spot weldability and good in workability by utilizing an acidic galvanizing bath contg. a pH buffering agent having pH buffer action within a prescribed pH range together with an oxidizer and utilizing the steel sheet as a cathode in this bath and forming a plated layer consisting of zinc oxide or zinc hydroxide on the surface of the steel sheet. CONSTITUTION:This acidic galvanizing bath is utilized and a steel sheet is utilized as a cathode. A plated layer consisting of oxide or hydroxide of zinc is formed on the surface of this steel sheet by electroplating. In this case, a pH buffering agent having pH buffer action in a range within 5-12pH is incorporated as an essential component into the galvanizing bath. As a result, the excessive rise of pH in the plating bath due to reduction of hydrogen is inhibited at a time of electroplating by this pH buffering agent. Therefore it is prevented that the build-up amount of plating consisting of oxide or hydroxide of zinc formed on the surface of the steel sheet is made excessive. The galvanized steel sheet having the above-mentioned characteristics is obtained.
Inventors:
SHIOBARA YUKIMITSU
ABE MASAKI
ABE MASAKI
Application Number:
JP6196190A
Publication Date:
November 25, 1991
Filing Date:
March 13, 1990
Export Citation:
Assignee:
NIPPON KOKAN KK
International Classes:
C25D9/08; (IPC1-7): C25D9/08
Attorney, Agent or Firm:
Natsuo Shiotani