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:
Apr. 20, 1993
Filed:
Jul. 31, 1992
Yasushi Hasegawa, Kanagawaken, JP;
Peter Ernst, Niederglatt, CH;
Fujimitsu Masuyama, Nagasakiken, JP;
Nippon Steel Corporation, Tokyo, JP;
Mitsubishi Jukogyo Kabushiki Kaisha, Tokyo, JP;
Abstract
A high-nitrogen ferritic heat-resisting steel comprises, in weight percent, 0.01-0.30% C, 0.02-0.80% Si, 0.20-1.00% Mn, 8.00-13.00% Cr, 0.50-3.00% W, 0.005-1.00% Mo, 0.05-0.50% V, 0.02-0.12% Nb and 0.10-0.50% N and is controlled to include not more than 0.050% P, not more than 0.010% S and not more than 0.020% O, the balance being Fe and unavoidable impurities. The steel may optionally comprise (A) one or both of 0.01-1.00% Ta and 0.01-1.00% Hf and/or (B) one or both of 0.0005-0.10% Zr and 0.01-0.10% Ti. A method of producing the steel comprises melting and equilibrating the steel components in an atmosphere of a mixed gas of a prescribed nitrogen partial pressure or nitrogen gas and thereafter casting or solidifying the melt in an atmosphere controlled to have a nitrogen partial pressure of not less than 1.0 ata and a total pressure of not less than 4.0 ata, with the relationship between the partial pressure p and the total pressure P.sub.t being