Patent ID: 6827755
Filing Date: 2004-12-07
Classification: B22F,C22C

Abstract:
A ferritic steel having high toughness and high strength, which consists essentially of, by weight, not more 1% Si, 8 to 30% Cr, each of C, N and O, the C, N and O being contained in amounts of more than 0%, and not more than 0.2% C, not more than 0.2% N, and not more than 0.4% O, a total amount of not more than 12% of at least one compound forming element selected from the group of Ti, Zr, Hf, V and Nb in amounts of not more than 3% Ti, not more than 6% Zr, not more than 10% Hf, not more than 1.0% V and not more than 2.0% Nb, and the balance of Fe and unavoidable impurities, and which has an average crystal grain size of not more than 1 &mgr;m, each of the C, N and O being combined with the at least one compound forming element.