The Ω and a conventional methods were applied to analyze the short-term creep behavior of a Mod.9Cr-1Mo steel. The stress and temperatuer ranges investigated are from 107.9 to 196.1 MP and from 873 to 923K, respectively. Creep life,
tr was related to the time to minimum creep (
tm), the minimum creep rate (ε
m) and the imaginary initial creep rate (ε
o ) as
tm =0.22×
tr1.03, ε
m Z·
tr KMG and ε
oY·
tr=
Ko, where the magnitudes of
Z,
KMG,
Y, and
Ko are 0.801, 0.332, 0.884 and 0.216, respectively. The constitutive equations for the minimum and imaginary initial creep rates are expressed as ε
m =
Am·σ
onm·exp (-
Qm/
RT) and ε
ο=
Ao·σ
ono exp(-
Qo/
RT), where
Am and
Ao are structure factors, σ
o is the initial stress,
nm and
no are the stress exponents, and
Nm,
NoQm and
Qο are the activation energies for the minimum creep rate and imaginary initial creep rate, respectively. The magnitudes of
Am,
Ao, N
Qm and
Qo are 9.2 × 10
3/s, 1.08 × 10
8/s, 12.8 ±0.2, 13.0±0.2, 666 ± 5 kJ/mol and 751 ±5kJ/mol, respectively.
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