Physical Metallurgy of Modern Creep-Resistant Steel for Steam Power Plants: Microstructure and Phase Transformations

Table 2

Stored energy as function of microstructure, defined relative to microstructure for which stored energy is arbitrarily set to zero [adapted from [4]].

Case	Microstructure	Stored energy, J/mol
Phase mixture in Fe-0.2C-1.5Mn wt% at 27°C
1	Ferrite, graphite, and cementite	0
2	Ferrite and cementite	70
3	Paraequilibrium ferrite and paraequilibrium cementite	385
4	Bainite and paraequilibrium cementite	785
5	Martensite	1214
Phase mixture in Fe-0.1C-2.2Cr-1Mn wt% at 600°C
6	Ferrite and paraequilibrium cementite → ferrite and (e.g., when steel enters service)	63
7	Ferrite and paraequilibrium cementite → ferrite and (e.g., after long service time)	0