The creep behavior of Fe–C alloys (1–1.8%C) was studied at homologous temperatures of 0.7 to 0.9, using strain rates of 1 to 100/s. The predominant deformation resistance was found to be climb-controlled dislocation creep and thus the creep rates were a function of the elastic modulus, lattice diffusivity and stacking fault energy. The self-diffusion coefficient of Fe in austenite was found to be a function only of Tm/T, and varied as: D(m2/s) = 6.8 x 10−6exp(-17Tm/T). The Fe–C alloys were observed to have a high stacking fault energy, which was unaffected by C and Mn. The stacking fault energy was observed to decrease with increasing concentrations of Si, Al and Cr. At high stresses, a deviation from power-law behavior was accounted for by considering contributions to diffusivity arising from dislocation pipe diffusion.

D.R.Lesuer, C.K.Syn, J.D.Whittenberger, M.Carsi, O.A.Ruano, O.D.Sherby: Materials Science and Engineering A, 2001, 317[1-2], 101-7