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:
Jun. 03, 2014
Filed:
Jun. 26, 2012
Kazuhito Imai, Amagasaki, JP;
Masanobu Ichikawa, Nisshin, JP;
Kazuhito Imai, Amagasaki, JP;
Masanobu Ichikawa, Nisshin, JP;
Nippon Steel & Sumitomo Metal Corporation, Tokyo, JP;
Toyoda Iron Works Co., Ltd., Aichi, JP;
Abstract
A method of producing a hot press-formed member having good corrosion resistance comprises subjecting a zinc-based plated steel sheet to heat treatment by heating to a temperature region of 600-750° C. at a rate of temperature increase up to 600° C. of at most 50° C. per second followed by cooling to 550° C. or below to form a steel blank which has a zinc oxide layer in its uppermost surface portion and below it a zinc-iron alloy phase having an Fe content of at least 25 mass %. This steel blank is heated to a temperature of at least its Acpoint, then press formed immediately at a temperature of at least its Acpoint, and then rapidly cooled. The hot press-formed member has a surface region with zinc oxide and iron-zinc solid solution phases and not containing an intermetallic compound phase or a pure zinc phase.