TY - JOUR
T1 - Crystallography and elastic anisotropy in fatigue crack nucleation at nickel alloy twin boundaries
AU - Zhang, Xiaoxian
AU - Stinville, Jean Charles
AU - Pollock, Tresa M.
AU - Dunne, Fionn P.E.
N1 - Funding Information:
Xiaoxian Zhang wishes to acknowledge the financial support provided by China Scholarship Council (CSC) and Fionn Dunne acknowledges with gratitude his Royal Academy of Engineering / Rolls-Royce research chair funding. Tresa Pollock and Jean-Charles Stinville acknowledge U.S. Dept. of Energy, Office of Basic Energy Sciences Program DE-SC0018901.
Funding Information:
Xiaoxian Zhang wishes to acknowledge the financial support provided by China Scholarship Council (CSC) and Fionn Dunne acknowledges with gratitude his Royal Academy of Engineering / Rolls-Royce research chair funding. Tresa Pollock and Jean-Charles Stinville acknowledge U.S. Dept. of Energy, Office of Basic Energy Sciences Program DE-SC0018901 .
Publisher Copyright:
© 2021 Elsevier Ltd
PY - 2021/10
Y1 - 2021/10
N2 - Fatigue crack nucleation at annealing twin boundaries (TBs) within polycrystal nickel-based superalloy René 88DT is investigated with a microstructure-sensitive crystal plasticity (CP) model, digital image correlation strain measurements and experimental SEM crack nucleation observations. Strong slip localizations at TBs were experimentally observed and predicted by the CP model, which also showed high predicted geometrically necessary dislocation and corresponding stored energy densities, capturing experimental observations of crack nucleation. In a systematic study, elastic anisotropy was found to drive local elastic constraint and hence resolved shear stress, slip activation, GND density and stored energy density, demonstrating for this reason that TBs are preferential sites for crack nucleation in this alloy. The parent grain / twin pair crystallographic orientation with respect to remote loading was also demonstrated to be key to slip activation parallel to TBs and hence to stored energy density and fatigue crack nucleation, and the range of most damaging parent grain orientations has been identified.
AB - Fatigue crack nucleation at annealing twin boundaries (TBs) within polycrystal nickel-based superalloy René 88DT is investigated with a microstructure-sensitive crystal plasticity (CP) model, digital image correlation strain measurements and experimental SEM crack nucleation observations. Strong slip localizations at TBs were experimentally observed and predicted by the CP model, which also showed high predicted geometrically necessary dislocation and corresponding stored energy densities, capturing experimental observations of crack nucleation. In a systematic study, elastic anisotropy was found to drive local elastic constraint and hence resolved shear stress, slip activation, GND density and stored energy density, demonstrating for this reason that TBs are preferential sites for crack nucleation in this alloy. The parent grain / twin pair crystallographic orientation with respect to remote loading was also demonstrated to be key to slip activation parallel to TBs and hence to stored energy density and fatigue crack nucleation, and the range of most damaging parent grain orientations has been identified.
UR - http://www.scopus.com/inward/record.url?scp=85109636141&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85109636141&partnerID=8YFLogxK
U2 - 10.1016/j.jmps.2021.104538
DO - 10.1016/j.jmps.2021.104538
M3 - Article
AN - SCOPUS:85109636141
SN - 0022-5096
VL - 155
JO - Journal of the Mechanics and Physics of Solids
JF - Journal of the Mechanics and Physics of Solids
M1 - 104538
ER -