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.

Date of Patent:
May. 02, 2006

Filed:

Aug. 07, 2003
Applicants:

Satoshi Ohtsuka, Higashi-Ibaraki-gun, JP;

Shigeharu Ukai, Higashi-Ibaraki-gun, JP;

Takeji Kaito, Higashi-Ibaraki-gun, JP;

Takeshi Narita, Higashi-Ibaraki-gun, JP;

Masayuki Fujiwara, Kobe, JP;

Inventors:

Satoshi Ohtsuka, Higashi-Ibaraki-gun, JP;

Shigeharu Ukai, Higashi-Ibaraki-gun, JP;

Takeji Kaito, Higashi-Ibaraki-gun, JP;

Takeshi Narita, Higashi-Ibaraki-gun, JP;

Masayuki Fujiwara, Kobe, JP;

Attorney:
Primary Examiner:
Int. Cl.
CPC ...
C22C 1/05 (2006.01); C22C 33/02 (2006.01);
U.S. Cl.
CPC ...
Abstract

In an oxide dispersion strengthened martensitic steel which comprises, by % by weight, 0.05 to 0.25% C, 8.0 to 12.0% Cr, 0.1 to 4.0% W, 0.1 to 1.0% Ti, 0.1 to 0.5% YOwith the balance being Fe and unavoidable impurities and in which YOparticles are dispersed in the steel, by adjusting the Ti content within the range of 0.1 to 1.0% so that an excess oxygen content Ex.O in steel satisfies [0.22×Ti (% by weight)<Ex.O (% by weight)<0.46×Ti (% by weight)], the oxide particles are finely dispersed and highly densified to thereby obtain an oxide dispersion strengthened martensitic steel excellent in high-temperature strength. It is also possible to reduce the amount of oxygen contamination in steel during the mechanical alloying of raw material powders to provide Ex.O within a predetermined range, by carrying out the mechanical alloying in an Ar atmosphere having a super purity of not less than 99.9999%, by reducing stirring energy during the mechanical alloying or by using a metal Y powder or an FeY powder in place of the YOpowder.


Find Patent Forward Citations

Loading…