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:
Aug. 23, 2022
Filed:
Apr. 16, 2018
Jfe Steel Corporation, Tokyo, JP;
Gentaro Takeda, Tokyo, JP;
Yoichi Makimizu, Tokyo, JP;
Gosuke Ikeda, Tokyo, JP;
Hideyuki Takahashi, Tokyo, JP;
JFE STEEL CORPORATION, Tokyo, JP;
Abstract
A method comprises: annealing a steel sheet by conveying the steel sheet through a heating zone, a soaking zone, and a cooling zone in the stated order in an annealing furnace; and then applying a hot-dip galvanized coating onto the steel sheet discharged from the cooling zone. Reducing or non-oxidizing humidified gas and reducing or non-oxidizing dry gas are supplied into the soaking zone. A CO gas concentration is measured using a CO gas concentration meter provided in an exhaust portion for gas in the soaking zone. A decarburized layer thickness of the steel sheet is calculated from the measured CO gas concentration. At least one of a flow rate and a dew point of the humidified gas is controlled so that the calculated decarburized layer thickness is less than or equal to a predetermined thickness.