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:
Jan. 29, 1991
Filed:
Dec. 12, 1989
Applicant:
Inventors:
Ryota Yamaba, Tokai, JP;
Yukio Tsuda, Tokai, JP;
Atsuo Tanaka, Tokai, JP;
Keiichi Hattori, Tokai, JP;
Assignee:
Nippon Steel Corporation, Tokyo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
C21D / ;
U.S. Cl.
CPC ...
148 124 ; 148 / ;
Abstract
High-strength steel having a tensile strength of 80 kgf/mm.sup.2 or more is produced by one-line quenching or on-line quenching and tempering. The steel has also excellent low-temperature toughness and excellent weldability, which makes high temperature preheating unnecessary prior to welding. The composition is: C=0.04% to 0.11%; Si.ltoreq.1.0%; Mn=0.5% to 2.00%, Mo=0.10% to 1.0%, Nb=0.005% to 0.05% B=0.0009% to 0.0012% Al.ltoreq.0.1%; and N.ltoreq.0.0060%.