Patent ID: 6899773

Claim:
A fine-grained iron base alloy in which the ASTM grain size number is greater than or equal to 5, consisting essentially of (wt. %): 0.05<C<0.15%, 7.5<Cr<15%, 2<Ni<5%, Co<4%, Cu<1.2%, Mn<5%, Si<1.0%, (Mo+W)<4%, 0.01<Ti<0.75%, Zr<1.6%, Ta<3.2%, Hf<3.2%, Ti, Zr, Ta, Hf present such that 0.135<(1.17Ti+0.6Zr+0.31Ta+0.31Hf)<1.0, N<0.02%, Al<0.2%, (Al+Si)>0.01, each of B, Ce, Mg, Sc, Y, La, and Be less than 0.1%, P<0.1%, S<0.03%, each of Sn, Sb, O and other impurities less than 0.04%, and the balance essentially iron.