To provide a production method by which an ingot of an Fe-Cr(-W) alloy having excellent heat resistance and high temperature corrosion resistance can be worked at high productivity without generating cracks, crazing or the like.
The alloy has a composition comprising, by mass, 30 to 80% Cr, 0.01 to 2.0% sol.Al and ≤0.20% Si, further comprising Ca, Ti and Nb so as to satisfy the following inequalities (1) and (2), respectively, and, if required, further comprising W as well, and the balance Fe with inevitable impurities: 1.5×S+2.0×P≤Ca≤0.1 (1), and 10.0×(C+N)≤(Ti+Nb)≤0.7 (2); wherein, S, P, Ca, C, N, Ti and Nb denote the mass% value of each element. In its production method, the ingot of the alloy is hot-worked at ≥800°C, is thereafter warm-treated at 800 to 1,200°C, and is subsequently subjected to hot working or cold working.
KATSUKI JUNICHI
TAKEMOTO TOSHIHIKO
NISSHIN STEEL CO LTD
Morio Nakamura