Imperial College London
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ProfessorRobinGrimes

Faculty of Engineering, Department of Materials

BCH Steele Chair in Energy Materials
 
 
 
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Contact

 

+44 (0)20 7594 6730r.grimes

 
 
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Location

 

B303cBessemer BuildingSouth Kensington Campus

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Summary

 

Publications

Citation

BibTex format

@article{Jackson:2021:10.1016/j.intermet.2020.106937,
author = {Jackson, M and Burr, P and Grimes, R},
doi = {10.1016/j.intermet.2020.106937},
journal = {Intermetallics},
pages = {1--10},
title = {Intrinsic defect migration in Be12Ti},
url = {http://dx.doi.org/10.1016/j.intermet.2020.106937},
volume = {128},
year = {2021}
}
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RIS format (EndNote, RefMan)

TY  - JOUR
AB  - Be12Ti is a leading candidate neutron-multiplier material for fusion breeder blankets; yet the evolution of the crystal defects under irradiation is poorly understood. Here, the migration of intrinsic defects in tetragonal Be12Ti was predicted using atomic scale computer simulation. Transport of titanium and beryllium through the interstitial, interstitialcy and vacancy-mediated models was considered, along with the migration of divacancy clusters, previously identified as important to the defect chemistry of Be12Ti. It was found that titanium defects exhibit much higher migration energies than beryllium for most migration pathways, leading to a dramatic difference in migration isotropy. Both beryllium vacancy and interstitial diffusion is close to isotropic with vacancy transport exhibiting the highest self-diffusion coefficient. Migration of beryllium di-vacancies is also isotropic with activation energy equal to that of isolated vacancies. The titanium interstitial exhibits significantly lower migration energy than its vacancy (1.00 eV and 6.75 eV respectively), with both mechanisms strongly anisotropic: the activation energy for [001] migration is at least 5 eV lower than other directions. Even the more exotic mixed titanium beryllium vacancy migration exhibits a much higher migration energy than [001] titanium interstitial transport. The framework used for predicting defect transport kinetics, including vacancy-mediated, interstitial and interstitialcy mechanisms, can be applied to any complex-structured intermetallic compound.
AU  - Jackson,M
AU  - Burr,P
AU  - Grimes,R
DO  - 10.1016/j.intermet.2020.106937
EP  - 10
PY  - 2021///
SN  - 0966-9795
SP  - 1
TI  - Intrinsic defect migration in Be12Ti
T2  - Intermetallics
UR  - http://dx.doi.org/10.1016/j.intermet.2020.106937
UR  - https://www.sciencedirect.com/science/article/pii/S0966979520304155?via%3Dihub
UR  - http://hdl.handle.net/10044/1/83120
VL  - 128
ER  -
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