Anticorrosive overlap-coated steel material

• US 4,190,504 A
• Filed: 10/06/1978
• Issued: 02/26/1980
• Est. Priority Date: 11/11/1977
• Status: Expired due to Term

• Current Assignee: Usui Kokusai Sangyo KK
• Original Assignee: Usui Kokusai Sangyo KK
• Inventors: Usui, Masayoshi
• Primary Examiner(s): Tufariello, T. M.
• Application Number:
  US05/949,132
• Time in Patent Office: 508 Days
• Field of Search: 204/40, 204/41, 204/56 R, 204/35 R, 428/935, 428/659, 428/629, 428/632, 428/648
• US Class Current: 205/50
• CPC Class Codes: C25D 5/10 Electroplating with more than one layer of the same or of different metals for bearings C25D7/10
• CPC Class Codes: Y10S 428/935 Electroplating
• CPC Class Codes: Y10T 428/12611 Oxide-containing component
• CPC Class Codes: Y10T 428/12722 Next to Group VIII metal-base component
• CPC Class Codes: Y10T 428/12799 Next to Fe-base component [e.g., galvanized]

Abstract

An anticorrosive overlapped coating so far practiced as applied to such iron and steel materials as plates, pipes, bars or wires is formed by electroplating an iron or steel material on the surface with an Sn base - Zn alloy layer and applying a chromate-treatment on it. However, this requires such long time in forming a plated layer thickness that a reduction of the plating time together with a further improvement of the anticorrosion is hoped for today. The present invention has succeeded in making it possible to reduce the plating time while improving the anticorrosion and in improving the productivity by forming an electroplated layer of an Sn base - Zn alloy directly or through an electroplated layer of Zn on the surface of a steel material, then forming an electroplated layer of Zn on the electroplated layer of said alloy and further applying a chromate-treatment on said Zn layer.

Claims

1. An anti-corrosive overlap-coated steel material made by forming an electroplated layer of an Sn base-Zn alloy directly on the skin surface of an iron or steel material, then forming an electroplated layer of zinc on said alloy layer and further applying a chromate-treatment on said zinc layer.

2. An anti-corrosive overlap-coated steel material made by forming an electroplated layer of an Sn base-Zn alloy through an electroplated layer of zinc on the skin surface of an iron or steel material, then forming an electroplated layer of zinc on said alloy layer and further applying a chromate-treatment on said zinc layer.