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. 22, 2008
Filed:
Aug. 07, 2003
Satoshi Ohtsuka, Higashi-Ibaraki-gun, JP;
Shigeharu Ukai, Higashi-Ibaraki-gun, JP;
Takeji Kaito, Higashi-Ibaraki-gun, JP;
Masayuki Fujiwara, Kobe, JP;
Satoshi Ohtsuka, Higashi-Ibaraki-gun, JP;
Shigeharu Ukai, Higashi-Ibaraki-gun, JP;
Takeji Kaito, Higashi-Ibaraki-gun, JP;
Masayuki Fujiwara, Kobe, JP;
Japan Nuclear Cycle Development Institute, Ibaraki, JP;
Abstract
A method of manufacturing an oxide dispersion strengthened ferritic steel excellent in high-temperature creep strength having a coarse grain structure. The method comprises mixing alloy powders and an YOpowder, subjecting the mixed powder to mechanical alloying treatment, solidifying the alloyed powder by hot extrusion, and subjecting the extruded solidified material to final heat treatment involving heating to and holding at a temperature of not less than the Actransformation point and slow cooling at a rate of not more than a ferrite-forming critical rate which comprises, 0.05-0.25% C, 8.0-12.0% Cr, 0.1-4.0% W, 0.1-1.0% Ti, 0.1-0.5% YOby weight, with the balance being Fe. In this method, by using a TiOpowder as a Ti component to be mixed at the mechanical alloying treatment or by adding a FeOpowder, the bonding of Ti with C is suppressed, and the C concentration in the matrix does not decrease.