To provide a Fe-Cr alloy having superior toughness, workability and high-temperature strength in spite of containing a high concentration of Cr.
In the Fe-Cr alloy comprising 30.0-50.0 mass% Cr, 0.1-10 mass% in total of W and/or Mo, and the balance substantially Fe, this Fe-Cr alloy is characterized by the total content of C and N controlled to 0.01 mass% or less, and the maximum grain size adjusted to a value L (μm) or less according to the Cr content, which is defined by L = 860-12×(mass% Cr) -8×(mass% W) -4×(mass% Mo). The Fe-Cr alloy can contain, as needed, 0.1-10 mass% in total of one or more of Ni and Al, and/or 0.01-1 mass% in total of one or more of Ti and Nb. The manufacturing method comprises hot-rolling or hot-forging the Fe-Cr alloy at an extraction temperature of 1,200°C or lower and the finishing temperature of 800°C or lower, and cooling it at an average cooling rate of 10°C/minute or higher down to 300°C. The method may include heat-treating the cooled Fe-Cr alloy at 1,050°C or lower.
KATSUKI JUNICHI
ISOZAKI SEIICHI
ABIKO KENJI
Okada Manri