Title:
GALVANIZED STEEL SHEET EXCELLENT IN LUBRICITY, CHEMICAL CONVERTIBILITY, COMPATIBILITY WITH ADHESIVE AND WELDABILITY
Document Type and Number:
Japanese Patent JP3153097
Kind Code:
B2
Abstract:
PURPOSE: To improve the lubricity, chemical convertibility or the like of a galvanized steel sheet by forming a ZnO-base oxide on the surface of a plating layer and forming a specified amt. of Mn-Zn-OH-P-base crystalline oxide on the upper layer.
CONSTITUTION: A galvanized steel sheet is brought into contact with an aq. soln. of an oxidizer contg. acid to form an oxide essentially consisting of ZnO by about 30 to 3000mg/m2 as the content of ZnO. As the oxidizer, e.g. HNO3 is used. Successively, it is brought into contact with an aq. soln. contg. potassium permanganate, sulfuric acid, potassium phosphate, phosphoric acid or the like in high concn., by which an Mn-Zn-OH-base crystalline oxide is formed by 0.1 to 100mg/m2 as the content of Mn and by 1 to 100mg/m2 as the content of P. Thus, the galvanized steel sheet excellent in compatibility with adhesives and weldability can be obtained.
Inventors:
Shinichi Suzuki
Tatsuya Kanamaru
Victory Arai
Tatsuya Kanamaru
Victory Arai
Application Number:
JP10611695A
Publication Date:
April 03, 2001
Filing Date:
April 28, 1995
Export Citation:
Assignee:
Nippon Steel Corporation
International Classes:
C23C22/78; C23C2/26; C23C28/00; (IPC1-7): C23C2/26; C23C28/00
Attorney, Agent or Firm:
Akio Najima (2 others)