Title:
ZINC PLATED STEEL SHEET HAVING SUPERIOR SPOT WELDABILITY AND PRODUCTION THEREOF
Document Type and Number:
Japanese Patent JPH0247292
Kind Code:
A
Abstract:
PURPOSE:To produce a Zn plated steel sheet having superior spot weldability by electroplating a steel sheet at a high current density in an acidic Fe-Zn alloy plating soln. to simultaneously form an Fe-Zn alloy plating layer as a lower layer and a layer of ZnO, Zn(OH)2, ZnFe2O4, etc., as an upper layer. CONSTITUTION:Electric current is supplied between a steel sheet as the cathode and a counter electrode as the anode at a high current density of 200-700A/dm<2> in an acidic Fe-Zn alloy plating soln. having <=10g/l concn. of an acid such as sulfuric acid or hydrochloric acid to simultaneously form an Fe-Zn alloy plating layer as a lower layer and a layer of Zn oxide such as ZnO, Zn(OH)2 or ZnFe2O4 as an upper layer on the surface of the steel sheet. The amt. of the upper layer is regulated to 0.03-3.0g/m<2> (expressed in terms of Zn). A Zn plated steel sheet having superior spot weldability can easily be produced.
Inventors:
YAMAZAKI KAZUMASA
Application Number:
JP19725988A
Publication Date:
February 16, 1990
Filing Date:
August 09, 1988
Export Citation:
Assignee:
NIPPON STEEL CORP
International Classes:
C25D5/26; C25D9/08; (IPC1-7): C25D5/26; C25D9/08
Attorney, Agent or Firm:
Tachio Chanogi
Next Patent: JPH0247293