Abstract
Pyrochlore oxides ((Formula presented.) are potential nuclear waste substrate materials due to their superior radiation resistance properties. We performed molecular dynamics simulations to study the structural properties and displacement cascades in ytterbium titanate pyrochlore ((Formula presented.)) and high-entropy alloys (HEPy), e.g., (Formula presented.), (Formula presented.), and (Formula presented.). We computed lattice constants (LC) ((Formula presented.)) and threshold displacement energy (Ed). Furthermore, the calculation for (Formula presented.) and ionic radius ((Formula presented.)) were performed by substituting a combination of cations at the A and B sites of the original pyrochlore structure. Our simulation results have demonstrated that the lattice constant is proportional to the ionic radius, i.e., (Formula presented.). Moreover, the effect of displacement cascades of recoils of energies 1 keV, 2 keV, 5 keV, and 10 keV in different crystallographic directions ([100], [110], [111]) was studied. The number of defects is found to be proportional to the energy of incident primary knock-on atoms (PKA). Additionally, the (Formula presented.) of pyrochlore exhibits anisotropy. We also observed that HEPy has a larger (Formula presented.) as compared with (Formula presented.). This establishes that (Formula presented.) has characteristics of lower radiation damage resistance than HEPy. Our displacement cascade simulation result proposes that HEPy alloys have more tendency for trapping defects. This work will provide atomic insights into developing substrate materials for nuclear waste applications.
Recommended Citation
M. M. Azeem and Q. Wang, "Atomic Insights into the Structural Properties and Displacement Cascades in Ytterbium Titanate Pyrochlore (Yb2ti2o7) and High-Entropy Pyrochlores," Journal of Composites Science, vol. 7, no. 10, article no. 413, MDPI, Oct 2023.
The definitive version is available at https://doi.org/10.3390/jcs7100413
Department(s)
Civil, Architectural and Environmental Engineering
Second Department
Mechanical and Aerospace Engineering
Publication Status
Open Access
Keywords and Phrases
displacement cascades; high-entropy alloys; LAMMPS; lattice constants; molecular dynamics simulation; nuclear waste substrate; ytterbium pyrochlore oxides
International Standard Serial Number (ISSN)
2504-477X
Document Type
Article - Journal
Document Version
Final Version
File Type
text
Language(s)
English
Rights
© 2024 The Authors, All rights reserved.
Creative Commons Licensing
This work is licensed under a Creative Commons Attribution 4.0 License.
Publication Date
01 Oct 2023
Included in
Aerospace Engineering Commons, Architectural Engineering Commons, Civil and Environmental Engineering Commons, Mechanical Engineering Commons
Comments
Fundamental Research Funds for the Central Universities, Grant 3072022JC1502