Title:
MULTI-PLY PLATED STEEL SHEET EXCELLENT IN WORKABILITY, CORROSION RESISTANCE AND WATER-RESISTANT ADHESION
Document Type and Number:
Japanese Patent JPH0324293
Kind Code:
A
Abstract:
PURPOSE:To produce the multi-ply plated steel sheet excellent in workability, corrosion resistance and water-resistant adhesion by plating the surface of a steel sheet with a Zn-Fe-Cr alloy in double layers and further forming an electrolytic chromate layer thereon. CONSTITUTION:One or both sides of a cold-rolled steel sheet are degreased with alkali, pickled and cleaned. The sheet is then electroplated with a Zn-Fe-Cr alloy contg., by weight, 3-15% Fe, 0.1-1% Cr and the balance Zn at 0.1g/m<2> per one side as the first layer. The sheet is further electroplated with a Zn-Fe-Cr alloy contg. 10-40% Fe, 1-30% Cr and the balance Zn at >=20g/m<2> as the second layer. The total amt. of the first and second plating layers is controlled to <=60g/m<2>. An electrolytic chromate layer consisting of the metallic Cr layer and hydrated Cr oxide layer is formed respectively at >=5mg/m<2> as the third layer, and the multi-ply plated steel sheet having appropriate characteristics as the automobile steel sheet is produced.
Inventors:
WATANABE TSUTOMU
SAGIYAMA MASARU
KAWABE MASAKI
MORITA MASAYA
SAGIYAMA MASARU
KAWABE MASAKI
MORITA MASAYA
Application Number:
JP15900289A
Publication Date:
February 01, 1991
Filing Date:
June 21, 1989
Export Citation:
Assignee:
NIPPON KOKAN KK
International Classes:
C25D5/26; C25D3/56; C25D5/10; C25D11/38; (IPC1-7): C25D5/26
Domestic Patent References:
| JPS59170288A | 1984-09-26 | |||
| JPS6479382A | 1989-03-24 |
Attorney, Agent or Firm:
Natsuo Shiotani
Next Patent: JPH0324294