TY - JOUR
T1 - Cyclic deformation mechanism and fracture behaviour of 316L stainless steel under thermomechanical fatigue loading
AU - Yin, Peng
AU - Zhang, Wei
AU - Zhang, Yi
AU - Yang, Qiaofa
AU - Liang, Fei
AU - Chang, Le
AU - Zhou, Changyu
N1 - Publisher Copyright:
© 2023 The Author(s)
PY - 2023/5/1
Y1 - 2023/5/1
N2 - Thermomechanical fatigue (TMF) behaviour of 316L is investigated based on the internal stress and microstructural characterization at various cyclic stages. Results reveal that the cyclic stress response shows initial hardening followed by cyclic softening at a high strain amplitude, while presenting continuous cyclic hardening as the strain amplitude decreases. Among these, Out-of-phase TMF always shows cyclic softening irrespective of strain amplitude. It is important to note that the hardening of back stress and friction stress contribute to the initial and subsequent cyclic hardening. In contrast, the subsequent cyclic softening is mainly dominated by the reduced friction stress. It is observed that the proliferation of dislocations at grain boundaries and the enhanced dislocation interactions within the grains are primarily responsible for the hardening of back stress and friction stress, respectively. Specifically, the cyclic softening of friction stress is attributed to the annihilated dislocations as a result of cross-slip. It is also found from the hysteresis curves that the intensity of dynamic strain ageing is related to strain amplitude, loading history and phase angle, which correlates to the occurrence of cross-slip, the diffusion rate of the solute atom, the density of point defect and the mobility of vacancies. Finally, the effect of loading conditions on fracture behaviour is demonstrated from the point view of crack sources, secondary cracks, creep cavities and oxidation damage.
AB - Thermomechanical fatigue (TMF) behaviour of 316L is investigated based on the internal stress and microstructural characterization at various cyclic stages. Results reveal that the cyclic stress response shows initial hardening followed by cyclic softening at a high strain amplitude, while presenting continuous cyclic hardening as the strain amplitude decreases. Among these, Out-of-phase TMF always shows cyclic softening irrespective of strain amplitude. It is important to note that the hardening of back stress and friction stress contribute to the initial and subsequent cyclic hardening. In contrast, the subsequent cyclic softening is mainly dominated by the reduced friction stress. It is observed that the proliferation of dislocations at grain boundaries and the enhanced dislocation interactions within the grains are primarily responsible for the hardening of back stress and friction stress, respectively. Specifically, the cyclic softening of friction stress is attributed to the annihilated dislocations as a result of cross-slip. It is also found from the hysteresis curves that the intensity of dynamic strain ageing is related to strain amplitude, loading history and phase angle, which correlates to the occurrence of cross-slip, the diffusion rate of the solute atom, the density of point defect and the mobility of vacancies. Finally, the effect of loading conditions on fracture behaviour is demonstrated from the point view of crack sources, secondary cracks, creep cavities and oxidation damage.
KW - Dynamic strain ageing
KW - Internal stress
KW - Microstructure evolution
KW - Thermomechanical fatigue
UR - http://www.scopus.com/inward/record.url?scp=85152936338&partnerID=8YFLogxK
U2 - 10.1016/j.jmrt.2023.04.113
DO - 10.1016/j.jmrt.2023.04.113
M3 - 文章
AN - SCOPUS:85152936338
SN - 2238-7854
VL - 24
SP - 4484
EP - 4499
JO - Journal of Materials Research and Technology
JF - Journal of Materials Research and Technology
ER -