| 摘要 |
PROBLEM TO BE SOLVED: To provide a method for producing a stainless steel excellent in ozone- contg. water resistance. SOLUTION: A stainless steel contg., by weight, <=0.03% C, <=1% Si, 12 to 30% Cr, 1 to 6% Al, one or more kinds among Mn, B, La, Ce, Y, Hf and Ca and one or more kinds among Ti, Nb and Zr is held at 105 to 1200 deg.C and also at the temp. satisfying the following inequality I and is thereafter cooled at >= a cooling rate S obtd. by the following inequality II or at a rate of >=5 deg.C/sec to <=700 deg.C, and after that, an oxide film essentially consisting of Al2 O3 is formed on the surface: the inequality I: [T( deg.C)]>=40×[Al wt.%]+920, and the inequality II: log[S]>=-1.7×log[t]+3.0, where T: temp., S: cooling rate ( deg.C/sec), and (t): the thickness (mm) of the material to be treated.
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