Patent · US Expired

Electroplated steel sheet having a plurality of coatings, excellent in workability, corrosion resistance and water-resistant paint adhesivity

US5006420A · kind A · utility

1Cited by
0References
2Claims
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Assignee

Inventors

Key dates

Filing dateMay 31, 1990
Grant dateApr 9, 1991
Priority date
Expiry dateMay 31, 2010

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T428/12799
  • WIPO fieldSurface technology, coating
  • WIPO sectorChemistry

Abstract

An electroplated steel sheet having a plurality of coatings, excellent in workability, corrosion resistance and water-resistant paint adhesivity, which comprises: PA0 an iron-chromium-zinc alloy coating as a lower layer, having a coating weight of from 0.1 to 40 g/m.sup.2 per side, formed on the surface of a steel sheet, consisting essentially of: PA1 iron: from 3 to under 15 wt. %, PA1 chromium: from 0.1 to 1 wt. %, and PA1 the balance being zinc and incidental impurities; PA0 another iron-chromium-zinc alloy coating as an intermediate layer, having a coating weight of from 20 to 59.9 g/m.sup.2 per side, formed on the iron-chromium-zinc alloy coating as the lower layer, consisting essentially of: PA1 iron: from 10 to 40 wt. %, PA1 chromium: from over 1 to under 30 wt. %, and PA1 the balance being zinc and incidental impurities; PA0 and a chromating coating as an upper layer, formed on the another iron-chromium-zinc alloy coating as the intermediate layer, which comprises a metallic chromium film and a hydrated chromium oxide film, each having a coating weight of at least 5 mg/m.sup.2 per side.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.