| 摘要 |
PROBLEM TO BE SOLVED: To provide a method for producing a Ti-containing ferritic oxide dispersion strengthened steel having a coarsened, equi-axed crystal grain structure effective for improving high temperature creep strength. SOLUTION: At the time when element powder or alloy powder and Y<SB>2</SB>O<SB>3</SB>powder are mixed, and the powdery mixture is subjected to mechanical alloying treatment, is solidified by hot extrusion, and is thereafter subjected to holding under heating to an Ac<SB>3</SB>transformation point or higher and the subsequent annealing heat treatment at a ferrite forming critical rate or lower as final heat treatment, so as to produce a ferritic oxide dispersion strengthened steel containing, by mass, 0.05 to 0.25% C, 8.0 to 12.0% Cr, 0.1 to 4.0% W, 0.1 to 1.0% Ti and 0.1 to 0.5% Y<SB>2</SB>O<SB>3</SB>, and the balance Fe with inevitable impurities, and in which Y<SB>2</SB>O<SB>3</SB>particles are dispersed, by adding Fe<SB>2</SB>O<SB>3</SB>powder to the raw material to be mixed by the mechanical alloying treatment, the bond of Ti and C is suppressed, thus the reduction of the C concentration in the matrix is prevented. COPYRIGHT: (C)2006,JPO&NCIPI
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