Fig. 1. Variation of the simulated (a) phase fraction and (b) average size of precipitates during heat treatment in NF709 austenitic steel [28].

Fig. 2. Equilibrium phase fractions of precipitates in 15Cr-15Ni austenitic steel as calculated by MatCalc [26].

Fig. 3. Various typical precipitates in TP347H austenitic heat-resistant steel: (a) SEM and (b) TEM micrographs of MX carbonitrides; (c) SEM and (d) TEM micrographs of M23C6 carbides; (e) TEM micrographs of Z phase; (f) EDS analysis of Z phase [45].

Fig. 4. Schematic of beaded M23C6 precipitates along dislocation lines in S31042 austenitic steel: (a) beaded precipitates (700 °C, 3000 h); (b) precipitates along dislocation lines [56].

Fig. 5. TEM micrograph showing grain boundary precipitate in the microstructure of Fe-20Cr-30Ni-2Nb austenitic steel after aging at 750 °C for 240 h: (a) Sigma phase [1]; (b) Laves phase [72].

Fig. 6. Schematic description of the coarsening model in Dictra Software. The moving phase interface between the particles (α) is in local equilibrium with the matrix (β). At the outer boundary the equilibrium is defined by the average composition in the system. The energy contribution due to the interfacial energy is 2σVm/rp for the largest particle and the other for the particles of average size [79].

Fig. 7. Typical TEM micrographs of extraction replica in type 347H steels after aging at 700 °C for 1 h (a), 500 h (b), 1000 h (c), 2200 h (d), respectively [80].

Fig. 8. SEM images of the base and Si-modified austenitic steels: (a) base alloy after aging at 800 °C for 100 h, (b) +Si steels after aging at 800 °C for 100 h [73].

Fig. 9. Calculated processing map of TP347H austenitic steel under an applied compression strain of 0.6 [84].

Fig. 10. Schematic representation of the grain refinement mechanisms operating in a stainless steel under warm rolling conditions [103].