Steel product with heat-resistant, corrosion-resistant plating layers

• US 5,246,786 A
• Filed: 06/22/1992
• Issued: 09/21/1993
• Est. Priority Date: 10/29/1988
• Status: Expired due to Term

• Current Assignee: Usui Kokusai Sangyo Kaisha Limited
• Original Assignee: Usui Kokusai Sangyo Kaisha Limited
• Inventors: Usui, Masayoshi
• Primary Examiner(s): NOT, DEFINED
• Assistant Examiner(s): Koehler, Robert R.
• Application Number:
  US07/900,795
• Time in Patent Office: 456 Days
• Field of Search: 428/632, 428/658, 428/659, 428/671, 428/674, 428/676, 428/677, 428/679, 428/680, 428/926, 428/621, 148/264, 148/265, 148/266, 148/267
• US Class Current: 428/621
• CPC Class Codes: C23C 22/78 Pretreatment of the material to be coated
• CPC Class Codes: C23C 28/00 Coating for obtaining at least two superposed coatings either by methods not provided for in a single one of groups C23C2/00 - C23C26/00 or by combinations of methods provided for in subclasses C23C and C25C or C25D
• CPC Class Codes: C25D 5/12 at least one layer being of nickel or chromium
• CPC Class Codes: C25D 5/48 After-treatment of electroplated surfaces
• CPC Class Codes: Y10S 428/926 Thickness of individual layer specified
• CPC Class Codes: Y10T 428/12535 with additional, spatially distinct nonmetal component
• CPC Class Codes: Y10T 428/12611 Oxide-containing component
• CPC Class Codes: Y10T 428/12792 Zn-base component
• CPC Class Codes: Y10T 428/12931 Co-, Fe-, or Ni-base components, alternative to each other
• CPC Class Codes: Y10T 428/12937 Co- or Ni-base component next to Fe-base component
• CPC Class Codes: Y10T 428/12944 Ni-base component

Abstract

A steel product (or copper-plated steel product) with heat-resistant, corrosion-resistant plating layers which are composed of a 0.2-10 μm thick nickel plating layer formed on said steel product, a zinc plating layer formed on said nickel plating layer, and a chromate film formed on said zinc plating layer.

Claims

1. A steel product composed of a steel substrate with heat-resistant, corrosion-resistant plating layers which are composed of a 0.2-10 μ

m thick nickel plating layer formed on said steel substrate, a zinc plating layer formed on said nickel plating layer, and a chromate film formed on said zinc plating layer.

2. A steel product as claimed in claim 1, wherein the nickel plating layer is one which is formed by electroplating using a Watts bath.

3. A steel product as claimed in claim 1, wherein the zinc plating layer is one which is formed by electroplating using a zinc chloride bath or zinc sulfate bath.

4. A steel product as claimed in claim 1, wherein said chromate film is one which is formed from a chromate solution or dichromate-sulfuric acid solution.

5. A steel product as claimed in claim 1, wherein said chromate film is one which is formed from a chromate treating solution for zinc plating.