| 摘要 |
To provide a ferritic stainless steel material for automobile exhaust gas passage components usable in a high-temperature range over 900° C. and even over 950° C. The ferritic stainless steel material has excellent heat resistance and low-temperature toughness and has a composition comprising, in terms of % by mass, at most 0.03% of C, at most 1% of Si, from 0.6 to 2% of Mn, at most 3% of Ni, from 10 to 25% of Cr, from 0.3 to 0.7% of Nb, from more than 1 to 2% of Cu, from 1 to 2.5% of Mo, from 1 to 2.5% of W, at most 0.15% of Al, from 0.03 to 0.2% of V, and at most 0.03% of N, and optionally containing any of B, Co, W, Ti, Zr, REM and Ca with a balance of Fe and inevitable impurities, and the composition satisfies restrictive formulae 1.2Nb+5Mo+6Cu>=11.5 and 15Nb+2Mo+0.5Cu>=10.5. The steel material has a texture where the total amount of Nb and Mo existing as a precipitation phase is at most 0.2% by mass.
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