The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Dec. 16, 1986
Filed:
May. 14, 1984
Kazuaki Kyono, Chiba, JP;
Shigeo Kurokawa, Chiba, JP;
Hajime Kimura, Chiba, JP;
Toshio Irie, Chiba, JP;
Kawasaki Steel Corporation, Kobe, JP;
Abstract
Highly corrosion resistant plated steel strips or sheets adapted for phosphate treatment and cathodic electrodeposition and intended for use in automobiles, are produced by electroplating at least one surface of a steel strip with an alloy consisting essentially of 0.0003 to 15% by weight of phosphorous, balance essentially iron, in a plating bath containing Fe.sup.2+ ions in an amount of from 0.3 mol/liter to the solubility limit and hypophosphorous acid and/or a hypophosphite in an amount of 0.001 to 25 g/liter expressed as NaH.sub.2 PO.sub.2.H.sub.2 O at a pH of 1.0 to 5.0, a temperature of 30.degree. to 60.degree. C., and a current density of from more than 20 to 200 A/dm.sup.2, preferably 40 to 150 A/dm.sup.2. A top coat can be applied thereover, of one element selected from the group consisting of Ni, Zn, Mn, and Ti, deposited on the Fe-P plating layer to a build-up of 5 to 50 mg/m.sup.2. A lower layer of zinc or a zinc alloy can also be electrodeposited on at least one surface of the steel strip, prior to formation of the Fe-P layer. A surface film can be formed by chemically treating the Fe-P plating layer with a phosphate.