Fatigue crack initiation and growth in 43Fe-25Ni-22.5Cr austenitic steel at a temperature of 700 °C

The effect of dwell on thermomechanical fatigue in superaustenitic steel Sanicro 25

“…In steels having the essential content of Cr, there is a strong tendency to the rapid formation of numerous Cr-rich particles of M 23 C 6 type 29 . M 23 C 6 particles nucleate rapidly preferentially at high angle grain boundaries which is in accord with the results of Mazánová et al 14 . Fig.…”

“…While straining at room temperature, the principal role is played by the localization of the cyclic plastic strain and formation of extrusions and intrusions within the grains 13,31 . In high temperature cycling the oxidation, namely the oxidation of the grain boundaries is a dominant damage mechanism 8,14 . It is similar to high temperature fatigue with dwells in high-strength superalloys 32 .…”

“…The original interest was devoted to the creep resistance 2,[4][5][6][7] Basic study of the low cycle fatigue at ambient and high temperature of Sanicro 25 8 and the study of its cyclic stress-strain response using statistical theory of the hysteresis loop 9 started a number of more thorough studies of this material. Transmission electron microscopy (TEM) was used to study the dislocation arrangement 10 , the sources of its extraordinary cyclic hardening 11 and damage mechanisms at room and at elevated temperatures [12][13][14][15][16][17][18][19] . Further study was devoted to the damage mechanisms in thermomechanical fatigue [20][21][22][23][24][25] .…”

Early damage and fatigue crack initiation at ambient and elevated temperatures in heat resistant austenitic steel

“…In the interior of the grains a thin protective layer of the chromium oxide is formed that prevents further oxidation of the material. Preferential formation of the chromium oxides and nucleation of M 23 C 6 chromium carbides at the grain boundaries [14] decreases the chromium content along the grain boundaries. As a result the grain boundaries are preferentially oxidized.…”

The effect of dwell on thermomechanical fatigue in superaustenitic steel Sanicro 25

“…The basic study of the low cycle fatigue with constant strain rate at constant ambient and high temperature of Sanicro 25 (isothermal fatigue [IF]) 33 and the study of its cyclic stress–strain response using statistical theory of the hysteresis loop 34 started a number of more thorough studies of this material. Transmission electron microscopy (TEM) was used to study the dislocation arrangement, 35 the sources of its extraordinary cyclic hardening 36 and the damage mechanisms at room and at elevated temperatures 23,37–43 …”