TY - JOUR
T1 - A crystal plasticity-based creep model considering the concurrent evolution of point defect, dislocation, grain boundary, and void
AU - Liang, Zhun
AU - Liu, Changmeng
AU - Cui, Yinan
N1 - Publisher Copyright:
© 2024
PY - 2024/12
Y1 - 2024/12
N2 - Creep poses a significant threat to the integrity and longevity of structural components at high-temperature. The most current understanding of creep mainly focuses on the coupled dynamics of point defects and dislocation, which may well describe the first and second stage of creep. However, the behavior of the three stages of creep is jointly controlled by point defect (vacancy) diffusion, dislocation glide, dislocation climb, grain boundary (GB) sliding, and void evolution. A critical knowledge gap still exists regarding how these different creep mechanisms are simultaneously coupled during the three stages of creep. In this work, a multi-physical mechanisms-based crystal plasticity model is proposed to consider the concurrent evolution of point defect, dislocation, GB, and void based on a unified thermodynamic framework. In-situ scanning electron microscope creep experiments and macroscopic creep experiments of Ti-6Al-4V were conducted to validate our model. The in-situ creep experiment directly revealed the GB sliding creep failure behavior of Ti-6Al-4V for the first time. The proposed model well predicts both the microscopic and macroscopic experimental behavior of creep. The contribution of different microstructure evolutions is discussed, and a phase diagram of the dominated creep mechanism is obtained. An in-depth analysis was conducted on the coupling effects and microstructure characteristics of different creep mechanisms. This work not only deepens our understanding of the micro creep mechanism but also offers valuable insights for designing materials with specific microstructures to enhance their creep resistance.
AB - Creep poses a significant threat to the integrity and longevity of structural components at high-temperature. The most current understanding of creep mainly focuses on the coupled dynamics of point defects and dislocation, which may well describe the first and second stage of creep. However, the behavior of the three stages of creep is jointly controlled by point defect (vacancy) diffusion, dislocation glide, dislocation climb, grain boundary (GB) sliding, and void evolution. A critical knowledge gap still exists regarding how these different creep mechanisms are simultaneously coupled during the three stages of creep. In this work, a multi-physical mechanisms-based crystal plasticity model is proposed to consider the concurrent evolution of point defect, dislocation, GB, and void based on a unified thermodynamic framework. In-situ scanning electron microscope creep experiments and macroscopic creep experiments of Ti-6Al-4V were conducted to validate our model. The in-situ creep experiment directly revealed the GB sliding creep failure behavior of Ti-6Al-4V for the first time. The proposed model well predicts both the microscopic and macroscopic experimental behavior of creep. The contribution of different microstructure evolutions is discussed, and a phase diagram of the dominated creep mechanism is obtained. An in-depth analysis was conducted on the coupling effects and microstructure characteristics of different creep mechanisms. This work not only deepens our understanding of the micro creep mechanism but also offers valuable insights for designing materials with specific microstructures to enhance their creep resistance.
KW - Creep
KW - Crystal plasticity
KW - Dislocation glide and climb
KW - Grain boundary sliding
KW - Vacancy diffusion
KW - Void evolution
UR - http://www.scopus.com/inward/record.url?scp=85204090587&partnerID=8YFLogxK
U2 - 10.1016/j.jmps.2024.105836
DO - 10.1016/j.jmps.2024.105836
M3 - Article
AN - SCOPUS:85204090587
SN - 0022-5096
VL - 193
JO - Journal of the Mechanics and Physics of Solids
JF - Journal of the Mechanics and Physics of Solids
M1 - 105836
ER -