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. 30, 2015
Filed:
Dec. 28, 2010
Il-ryoung Sohn, Gwangyang, KR;
Jong-sang Kim, Gwangyang, KR;
Joong-chul Park, Gwangyang, KR;
Yeol-rae Cho, Gwangyang, KR;
Jin-keun OH, Gwangyang, KR;
Han-gu Cho, Gwangyang, KR;
Bong-hoon Chung, Gwangyang, KR;
Jong-seog Lee, Gwangyang, KR;
Il-Ryoung Sohn, Gwangyang, KR;
Jong-Sang Kim, Gwangyang, KR;
Joong-Chul Park, Gwangyang, KR;
Yeol-Rae Cho, Gwangyang, KR;
Jin-Keun Oh, Gwangyang, KR;
Han-Gu Cho, Gwangyang, KR;
Bong-Hoon Chung, Gwangyang, KR;
Jong-Seog Lee, Gwangyang, KR;
POSCO, Pohang-si, KR;
Abstract
Provided is a zinc-plated steel sheet for hot pressing having outstanding surface characteristics, comprising: a steel foundation plate comprising a metal surface diffusion layer of which the Gibbs free energy reduction per mole of oxygen during oxidation is less than that of Cr; an aluminum-rich layer containing at least 30 wt. % of aluminum formed on the surface diffusion layer, and a zinc plating layer formed on the aluminum-rich layer. In this way, a metal having a low affinity for oxygen is coated to an effective thickness prior to annealing and thus the creation of annealing oxides at the surface of the steel sheet is suppressed and a uniform zinc plating layer is formed, and alloying of the zinc plating layer is promoted during press-processing heat treatment. Cracking in the steel foundation plate during hot press molding is prevented.