Article
Nuclear Science & Technology
Chuanguo Zhang, Qirong Zheng, Yonggang Li, Liuming Wei, Fan Cheng, Zhi Zeng
Summary: In this study, a model called PradG is proposed to generate reliable primary radiation damage quickly by sampling limited molecular dynamics databases. The size and radial distribution of cascade clusters in body-centered-cubic W are analyzed, and a piecewise power-law formula and Gaussian/ exponential decay types are found for size and radial distribution, respectively. Based on these findings, PradG is developed to generate primary defects of arbitrary cascade energies. The reliability and validation of PradG are verified by comparing with cascade annealing simulations and defect evolution in fission neutron irradiated W.
NUCLEAR MATERIALS AND ENERGY
(2023)
Article
Materials Science, Multidisciplinary
J. Wu, F. Granberg
Summary: Tungsten is chosen as the material for demanding parts in fusion test reactors and power plants. Material degradation due to irradiation necessitates component replacement. Understanding how defects are formed is crucial for predicting replacement needs. Low energy simulations and Frenkel-pair insertion method are compared to investigate the potential of the latter in accelerating cascade simulations. Results show similarities qualitatively, but differences quantitatively, particularly at higher energies.
JOURNAL OF NUCLEAR MATERIALS
(2023)
Article
Materials Science, Multidisciplinary
A. Fellman, A. E. Sand
Summary: This study investigates the effect of different primary recoil energies on defect formation in tungsten through molecular dynamics simulations. It is found that pre-existing radiation-induced defects modify the number of additional defects formed during cascades. Furthermore, the formation of dislocation loops in cascades is more dependent on the size of pre-existing voids rather than the energy of the primary recoil.
JOURNAL OF NUCLEAR MATERIALS
(2022)
Article
Chemistry, Physical
Yaoxu Xiong, Jun Zhang, Shihua Ma, Shasha Huang, Biao Xu, Shijun Zhao
Summary: Multi-principal element alloys (MPEAs) have attracted attention for their exceptional mechanical properties and resistance to irradiation. This study combines molecular dynamics (MD) and cluster dynamics (CD) to model defect evolution in body-centered cubic (BCC) MPEAs, allowing for the analysis of factors affecting their irradiation performance.
JOURNAL OF ALLOYS AND COMPOUNDS
(2023)
Article
Materials Science, Multidisciplinary
F. Granberg, J. Byggmastar, K. Nordlund
Summary: Tungsten is chosen as the plasma-facing wall material in fusion reactors due to its high density and melting point. Research shows that the choice of interatomic potential significantly affects the evolution of defects, while the structure and stability of defect configurations can be validated using a quantum-accurate Gaussian approximation potential.
JOURNAL OF NUCLEAR MATERIALS
(2021)
Article
Materials Science, Multidisciplinary
Hao Sun, Laurent Karim Beland
Summary: This study investigates the statistical distribution of recombination radii in FCC and BCC metals using the kinetic activation relaxation technique and molecular dynamics simulations. The findings show that recombination can occur from the 2nd to the 15th nearest neighbor sites, with long-range recombination facilitated by crowdion formation along specific directions. The study also reveals that the average recombination radius is determined by elastic constants rather than energy barriers.
Article
Multidisciplinary Sciences
Max Boleininger, Daniel R. Mason, Andrea E. Sand, Sergei L. Dudarev
Summary: Below the onset of vacancy migration, metals exposed to energetic ions develop fluctuating steady-state microstructures. The statistical properties of these microstructures in the high exposure limit depend on the energy and mass of the incident ions. A model is developed to describe the microstructure of an ion-irradiated metal under athermal conditions, where internal stress fluctuations dominate the structural evolution kinetics. The model predicts that low energy ions produce more damage than high energy ions at comparable levels of radiation exposure.
SCIENTIFIC REPORTS
(2023)
Article
Materials Science, Multidisciplinary
Yi Wang, Jianbo Liu, Jiahao Li, Jinna Mei, Zhengcao Li, Wensheng Lai, Fei Xue
Summary: This work presents a machine-learning interatomic potential for bcc iron that shows good transferability and accurate reproduction of various properties relevant to radiation damage effects. The potential has general purposed applicability and enables simulation of radiation damage effects in bcc iron with an accurate and unified theoretical model.
COMPUTATIONAL MATERIALS SCIENCE
(2022)
Article
Materials Science, Multidisciplinary
Xiao-Tong Li, Xiao-Zhi Tang, Ya-Fang Guo
Summary: Grain boundaries (GBs) are potent defect sinks that reduce radiation damage in materials. This study systematically investigates the GB-mediated reduction of radiation defects in four W-based alloys and finds that the defect reduction in W-based alloys is significantly lower than in pure W due to strong solute-defect binding interactions. Solute with high local stress enhances the absorption of interstitials by GB. The ability of GB to absorb interstitials is enhanced with increasing temperature, and the accumulation of vacancies also increases at high temperatures. These findings provide useful information for the design of radiation tolerance materials.
METALS AND MATERIALS INTERNATIONAL
(2023)
Article
Materials Science, Multidisciplinary
F. Granberg, D. R. Mason, J. Byggmaestar
Summary: Tungsten is the preferred material for plasma-facing components in fusion reactors. Computer simulations are necessary to understand defect accumulation at an atomistic level. This article investigates accelerated methods for simulating defect evolution and compares them to computationally heavy cumulative simulations. It is found that the acceleration technique chosen can significantly affect defect evolution, but applying cascade annealing can lead to similar results regardless of the initial technique used.
COMPUTATIONAL MATERIALS SCIENCE
(2023)
Article
Chemistry, Multidisciplinary
Liuming Wei, Chuanguo Zhang, Qirong Zheng, Zhi Zeng, Yonggang Li
Summary: This study investigates the effects of defect size and spatial distributions on the annealing of individual cascades using molecular dynamics (MD) and object kinetic Monte Carlo (OKMC) simulations. MD simulations of tungsten cascades are carried out with two atomistic potentials, revealing distinct interstitial cluster (IC) size distributions and defect spatial distributions for cascade energies above 30 keV. Additionally, OKMC simulations demonstrate that larger-sized ICs and closely distributed self-interstitial atoms (SIAs) in cascade regions lead to higher recombination fractions during individual cascade annealing. Therefore, attention should be given to the size and spatial distributions of defects in the multi-scale simulation framework.
Article
Chemistry, Physical
Zhihan Hu, Di Chen, SeungSu Kim, Rijul Chauhan, Yongchang Li, Lin Shao
Summary: The effect of stress on irradiation responses of highly oriented pyrolytic graphite (HOPG) was studied using molecular dynamics simulation, proton irradiation, and Raman characterization. The results showed that stress reduces the average threshold displacement energy, increases the damage peak and the number of surviving defects, and induces local cleavage. Experimental results also confirmed the enhanced irradiation effect caused by stress.
Article
Chemistry, Physical
Xiaorong Liu, Dongpeng Hua, Wan Wang, Qing Zhou, Shuo Li, Junqin Shi, Yixuan He, Haifeng Wang
Summary: This study investigated the initial dislocation nucleation and motion mechanisms in TaTiZrV high-entropy alloys (RHEAs) and their dependence on temperature through molecular dynamics simulations. The short-range orders in the RHEA facilitate preferential inhomogeneous nucleation at low stress, while compositional fluctuation affects the slipping and moving rate of dislocations. Moreover, the difficulty of initial dislocation nucleation increases with temperature.
JOURNAL OF ALLOYS AND COMPOUNDS
(2022)
Article
Chemistry, Physical
Shiddartha Paul, Daniel Schwen, Michael P. Short, Anna Erickson, Kasra Momeni
Summary: Multimetallic layered composites (MMLCs) have great potential for applications under extreme environments due to their low oxidation tendency and high corrosion resistance. However, the understanding of the interface characteristics and the interaction with defects in MMLCs is still lacking. In this study, atomistic simulations were conducted on Inconel-Ni MMLCs to investigate the role of interlayer phases and their effect on defect mobility and radiation resistance. The results indicate that the misorientation angle of the interlayer influences the defect formation and radiation-induced material degradation.
JOURNAL OF ALLOYS AND COMPOUNDS
(2022)
Article
Materials Science, Multidisciplinary
Hongjiang Li, Long Zhao, Yang Yang, Hongxiang Zong, Xiangdong Ding
Summary: Molecular dynamic simulations show that in refractory bcc complex concentrated alloys containing Mo, Nb, Ta, and W elements, alloys with low binding energy of interstitial clusters, such as MoNb and NbW, exhibit good radiation resistance. The binding energy of interstitial clusters can be highly tunable by changing elements combination and compositional heterogeneities, paving the way for new design concepts of radiation-tolerant alloys.
JOURNAL OF NUCLEAR MATERIALS
(2021)
Article
Materials Science, Multidisciplinary
Jan Fikar, Roman Groger, Robin Schaeublin
JOURNAL OF NUCLEAR MATERIALS
(2017)
Article
Materials Science, Multidisciplinary
Wenwang Wu, Robin Schaublin
JOURNAL OF NUCLEAR MATERIALS
(2018)
Article
Crystallography
Martin Friak, Vilma Bursikova, Nadezda Pizurova, Jana Pavlu, Yvonna Jiraskova, Vojtech Homola, Ivana Mihalikova, Anton Slavik, David Holec, Monika Vsianska, Nikola Koutna, Jan Fikar, Dusan Janickovic, Mojmir Sob, Jorg Neugebauer
Article
Chemistry, Multidisciplinary
Martina Cihova, Patrik Schmutz, Robin Schaublin, Jorg F. Loffler
ADVANCED MATERIALS
(2019)
Article
Instruments & Instrumentation
Jan Fikar, Robin Schaeublin
NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS
(2020)
Article
Physics, Applied
Leonardo Pierobon, Robin E. Schaublin, Andras Kovacs, Stephan S. A. Gerstl, Alexander Firlus, Urs Wyss, Rafal E. Dunin-Borkowski, Michalis Charilaou, Jorg F. Loffler
Summary: The microstructure of different Sm(Co, Fe, Cu, Zr) alloys has been found to significantly influence the magnetic performance, affecting magnetic domain size, density, and forming different micromagnetic spin structures. Factors such as Cu concentration, cell-wall density, and Z-phase platelet thickness impact the coercivity. Detailed guidelines are provided for improving the design of Sm(Co, Fe, Cu, Zr) magnets based on atomic to nanoscale microstructural effects on magnetic performance.
JOURNAL OF APPLIED PHYSICS
(2021)
Article
Materials Science, Multidisciplinary
I Basu, M. Chen, J. Wheeler, R. E. Schaeublin, J. F. Loeffler
Summary: Experimental study on magnesium alloy ZX10 with lean additions of Zn and Ca reveals significant strengthening and plasticity enhancement through deformation twinning and multiple dislocation activation. The minute additions of Zn and Ca solutes modify the intrinsic stacking-fault energy, leading to the design of high-strength, highly ductile magnesium alloys.
Article
Physics, Applied
Leonardo Pierobon, Robin E. Schaublin, Jorg F. Loffler
Summary: Magnetization structures in magnetic materials are typically imaged in dedicated Lorentz transmission electron microscopes. However, for permanent magnets, conventional microscopes can also provide comparable resolution. Experimental results demonstrate that both conventional and Lorentz microscopes offer almost identical resolution and accuracy when imaging divergent and convergent domain walls in magnetic materials.
APPLIED PHYSICS LETTERS
(2021)
Article
Materials Science, Multidisciplinary
Severin Kuechler, Vladimir Vojtech, Stephan S. A. Gerstl, Robin E. Schaeublin, Joerg F. Loeffler
Summary: Binary Fe-Cr alloys are model alloys for ferritic steels proposed as structural materials for future fusion reactors. Through investigating the degradation mechanisms induced by heat and irradiation, the phase decomposition and hardness changes of Fe-Cr alloys were studied. The relationship between alloy strength and the α' structure was found, showing that this type of hardening is a general mechanism for mature systems, independent of the nominal alloy composition.
ADVANCED ENGINEERING MATERIALS
(2022)
Article
Materials Science, Multidisciplinary
R. E. Schaublin, M. Becker, M. Cihova, S. S. A. Gerstl, D. Deiana, C. Hebert, S. Pogatscher, P. J. Uggowitzer, J. F. Loffler
Summary: The impact of Zn and Ca on the microstructure of lean Mg-Zn-Ca alloys was investigated. The precipitation of binary and ternary precipitates was observed at different temperatures. Hardness testing revealed that GP zones were the most effective factor in hardening.
Article
Materials Science, Multidisciplinary
V. Vojtech, M. Charilaou, A. Kovacs, A. Firlus, S. S. A. Gerstl, R. E. Dunin-Borkowski, J. F. Loeffler, R. E. Schaeublin
Summary: The Fe-Cr alloy system can undergo phase separation and embrittlement when exposed to elevated temperatures and radiation, affecting its magnetic properties. By studying the microstructural decomposition induced by annealing, it is found that increasing annealing time leads to increased hardness, magnetic saturation, and coercivity.
Article
Nanoscience & Nanotechnology
Lucia Bajtosova, Barbora Krivska, Rostislav Kralik, Jozef Vesely, Jan Hanus, Petr Harcuba, Jan Fikar, Ankit Yadav, Miroslav Cieslar
Summary: This study used molecular dynamics simulation method to investigate the mechanical properties of thin aluminum-based films, and compared the results with transmission electron microscope experiments. The simulation results matched well with the experimental results, revealing the importance of grain boundary processes in deformation.
SCRIPTA MATERIALIA
(2022)
Article
Crystallography
Julie Soderlind, Aiden A. Martin, Nicholas P. Calta, Philip J. DePond, Jenny Wang, Bey Vrancken, Robin E. Schaeublin, Indranil Basu, Vivek Thampy, Anthony Y. Fong, Andrew M. Kiss, Joel M. Berry, Aurelien Perron, Johanna Nelson Weker, Kevin H. Stone, Christopher J. Tassone, Michael F. Toney, Anthony Van Buuren, Joerg F. Loeffler, Subhash H. Risbud, Manyalibo J. Matthews
Summary: This study investigates the laser-material interaction and microstructure of magnesium-based alloy WE43 under laser powder bed fusion (LPBF) conditions. The results reveal the characteristics of melt-pool dynamics, pore formation, and microstructure under different laser parameters, providing critical information for the successful implementation of LPBF-produced WE43 implants in biomedical applications.
Article
Nuclear Science & Technology
Jan Fikar, Robin Schaublin, Daniel R. Mason, Duc Nguyen-Manh
NUCLEAR MATERIALS AND ENERGY
(2018)
Article
Materials Science, Multidisciplinary
Liuming Wei, Jingwen Li, Yonggang Li, Qirong Zheng, Fan Cheng, Chuanguo Zhang, Jingyu Li, Gaofeng Zhao, Zhi Zeng
Summary: This study investigates the influence of He-V complexes on H behaviors on different W surfaces using DFT calculations. The results show that H dissolution is most difficult but H trapping is easiest on the W (110) surface, while the opposite is true on the W (111) surface. Moreover, the presence of He-V complexes increases the difficulty of H diffusion from bulk to surface and desorption.
JOURNAL OF NUCLEAR MATERIALS
(2024)
Article
Materials Science, Multidisciplinary
Yan Meng, Song Zeng, Chen Chen, Chaowen Zhu, Huahai Shen, Xiaosong Zhou, Xiaochun Han
Summary: The characteristics of magnetron sputtered Cr coatings vary with different temperature, bias voltage, and pressure. Coatings with random orientation, good crystallinity, and small grain size exhibit favorable oxidation behavior, while coatings with strong (200) texture, poor crystallinity, and large grains have many intrinsic defects that are detrimental to the protection property of the Cr coatings.
JOURNAL OF NUCLEAR MATERIALS
(2024)
Article
Materials Science, Multidisciplinary
Xinyuan Xu, Zefeng Yu, Wei-Ying Chen, Aiping Chen, Arthur Motta, Xing Wang
Summary: This study presents an automated approach for characterizing grain morphology in TEM images recorded during ion irradiation. By combining a machine learning model and a computer vision algorithm, comparable results to human analysis can be achieved with significantly reduced analysis time. Researchers can train their own models following the procedures described in this study to automate grain morphology analysis of their own TEM images.
JOURNAL OF NUCLEAR MATERIALS
(2024)
Article
Materials Science, Multidisciplinary
Shihao Wu, Dong Wang, Yapei Zhang, Koji Okamoto, Marco Pellegrini, Wenxi Tian, Suizheng Qiu, G. H. Su
Summary: The oxidation and degradation mechanisms of Cr coating on Zr alloy cladding under high temperature steam atmosphere are summarized, and a mathematical analysis model is established to predict the changes in coating thickness. The model is applied in the analysis of structure evolution under different conditions.
JOURNAL OF NUCLEAR MATERIALS
(2024)
Article
Materials Science, Multidisciplinary
V. Diaz-Mena, J. de Prado, M. Roldan, I. Izaguirre, M. Sanchez, M. Rieth, A. Urena
Summary: The brazeability of a cupronickel alloy was evaluated as a filler alloy for high-temperature joining of tungsten to steel. The study investigated the brazing conditions and the impact of the selected filler on the joint quality using numerical software. The results showed different metallurgical interactions and diffusion phenomena between the filler alloy and the base materials at different temperatures. The study emphasized the importance of selecting a suitable filler to mitigate residual stresses in the joints.
JOURNAL OF NUCLEAR MATERIALS
(2024)
Article
Materials Science, Multidisciplinary
Pengcheng Zhu, Yajie Zhao, Yan-Ru Lin, Jean Henry, Steven J. Zinkle
Summary: This study investigates the effect of heavy-ion irradiation on radiation hardening in high-purity binary alloy Fe18Cr. Nanoindentation testing and high-quality TEM imaging were conducted to extract hardness and microstructure information. The strength factor was accurately calculated based on the detailed TEM characterization of irradiated microstructures, and a refined hardening superposition method was applied to quantify the mechanical properties of ion-irradiated materials.
JOURNAL OF NUCLEAR MATERIALS
(2024)
Article
Materials Science, Multidisciplinary
Bin Wu, Haixia Ning, Hanzhen Zhu, Jianjun Chen, Kang Wang, Daiyu Zhang, Fu Wang, Qilong Liao
Summary: This study discusses the effects of ZrO2 and B2O3 on the phase composition and properties of SAP-based glass-ceramics. The results show that ZrO2 addition improves the formation of NZP phase while restricting the crystallization of AlPO4 phases. The correct ratios of ZrO2 and B2O3 allow only the formation of NZP phase within the SAP glass.
JOURNAL OF NUCLEAR MATERIALS
(2024)
Article
Materials Science, Multidisciplinary
Hwasung Yeom, Greg Johnson, Benjamin Maier, Tyler Dabney, Kumar Sridharan
Summary: Cr-Nb bilayer coatings were developed using cold spray deposition to improve the limiting operational temperature of Cr-coated Zr-alloy system. The coatings exhibited outstanding oxidation resistance at high temperatures and formed continuous intermetallic compound layers at the interfaces.
JOURNAL OF NUCLEAR MATERIALS
(2024)
Article
Materials Science, Multidisciplinary
Padhraic L. Mulligan, Andrew T. Nelson, Chad M. Parish, Patrick A. Champlin, Xiang Chen, Daniel Morrall, Jason M. Harp
Summary: Environmental barrier coatings are being developed to reduce oxidation and embrittlement in Zr-based materials. Chromium nitride is a candidate for this application, but understanding its impact on irradiation-induced creep and microstructure is critical.
JOURNAL OF NUCLEAR MATERIALS
(2024)
Article
Materials Science, Multidisciplinary
Dexuan Yan, Xinlei Cao, Ke Shen
Summary: This study investigated the purification mechanism of polycrystalline graphite by comparing IG-11 graphite with IG-110 nuclear grade graphite. The analysis revealed that metallic impurities in IG-11 were primarily segregated within graphite porosities, while IG-110 demonstrated a significant reduction in impurities. This research contributes to the development of innovative graphite purification techniques for greater purity and stronger oxidation resistance.
JOURNAL OF NUCLEAR MATERIALS
(2024)
Article
Materials Science, Multidisciplinary
Wei Xu, Wei Peng, Lei Shi, Qi Sun
Summary: This paper investigates the oxidation and shape evolution of matrix graphite in high temperature gas-cooled reactors during air-ingress accidents. A reaction kinetics model is established and computational fluid dynamics with a dynamic mesh method is used to simulate the oxidation process. The results show that the geometric shape of graphite changes significantly with increasing flow rate, and the graphite pebbles tend to form a structure with a narrow front and wide tail.
JOURNAL OF NUCLEAR MATERIALS
(2024)
Article
Materials Science, Multidisciplinary
Allison Harward, Casey Elliott, Michael Shaltry, Krista Carlson, Tae-Sic Yoo, Guy Fredrickson, Michael Patterson, Michael F. Simpson
Summary: This paper investigates the hygroscopic properties of eutectic LiCl-KCl absorbed into zeolite-4A. The study finds that water absorption and corrosion worsen with increasing salt loading. It also suggests that the salt can be stored in a non-inert atmosphere for a certain period of time.
JOURNAL OF NUCLEAR MATERIALS
(2024)
Article
Materials Science, Multidisciplinary
Takaaki Koyanagi, Xunxiang Hu, Christian M. Petrie, Gyanender Singh, Caen Ang, Christian P. Deck, Weon-Ju Kim, Daejong Kim, James Braun, Yutai Katoh
Summary: This study provides critical experimental data on the effects of irradiation on the hermeticity of SiC composite cladding, finding that irradiation can cause a decrease in hermeticity and cracking, and coating the outer surface can mitigate the cracking issue.
JOURNAL OF NUCLEAR MATERIALS
(2024)
Article
Materials Science, Multidisciplinary
S. Krat, A. Prishvitsyn, Yu. Gasparyan
Summary: This study proposes a probabilistic and diffusion-based model to describe the co-deposition of multiple hydrogen isotopes with slowly grown metal layers. The model calculates the relative concentrations of different hydrogen isotopes in the co-deposited metal layers. It is found that if hydrogen isotopes have different detrapping energies, only the isotope with the highest detrapping energy shows a monotonic decrease in concentration with deposition temperature. Furthermore, the study evaluates the uncertainty of tritium concentration in the co-deposited layer based on the uncertainty in detrapping energy of tritium and deuterium, predicting a >10% tritium concentration uncertainty for a 0.01 eV difference.
JOURNAL OF NUCLEAR MATERIALS
(2024)
Article
Materials Science, Multidisciplinary
Tijo Vazhappilly, Arup Kumar Pathak
Summary: This study investigates the effect of Ce atom substitution in UO2 on its thermophysical properties using density functional theory. The results show that the Ce substitution levels and the oxidation state of Ce/U atoms strongly influence the band structure and specific heat capacity of the UO2 lattice. These findings provide important insights into the fuel properties of UO2 under reactor conditions.
JOURNAL OF NUCLEAR MATERIALS
(2024)