Article
Materials Science, Multidisciplinary
Linggen Kong, Inna Karatchevtseva, Yingjie Zhang, Tao Wei
Summary: This study investigated the formation of zirconolite in three sets of ceramic and glass-ceramic systems under different sintering conditions, analyzing the composition doping and phase transformation. Various techniques were used to study the crystal structure, morphologies, and composition distribution.
JOURNAL OF NUCLEAR MATERIALS
(2021)
Article
Materials Science, Ceramics
Kexin Lv, Hengcheng Wan, Yi Li, Shengtai Zhang, Qiang He
Summary: The garnet structure Y3Fe5O12 (YIG) is highly effective in immobilizing actinides, but research on its sensitivity to irradiation damage is still limited. In this study, Y3-xNdxFe5O12 (x = 0.1, 1.8) ceramics were synthesized and irradiated with 2 MeV alpha-particle irradiation at different fluences. The effects of irradiation damage on phase transition and chemical stability were evaluated. Irradiation resulted in the formation of an amorphous layer, but the grain shape and element distribution remained uniform. The Y3-xNdxFe5O12 ceramics exhibited excellent chemical stability during leaching. The topological structure of garnet limited changes in radiation tolerance, indicating that garnet of different compositions would have similar and predictable radiation tolerance.
CERAMICS INTERNATIONAL
(2023)
Article
Chemistry, Physical
Ahmad R. Kirmani, Brandon K. Durant, Jonathan Grandidier, Nancy M. Haegel, Michael D. Kelzenberg, Yao M. Lao, Michael D. McGehee, Lyndsey McMillon-Brown, David P. Ostrowski, Timothy J. Peshek, Bibhudutta Rout, Ian R. Sellers, Mark Steger, Don Walker, David M. Wilt, Kaitlyn T. VanSant, Joseph M. Luther
Summary: Perovskite photovoltaics have great potential in terrestrial and space energy production, but their radiation tolerance needs to be analyzed. This article presents guidelines for rigorously testing the radiation tolerance of perovskite photovoltaics.
Article
Chemistry, Physical
Xinlei Zhang, Bin-Bin Zhang, Xiao Ma, Maosen Fu, Gangqiang Zha, Wanqi Jie
Summary: This study systematically investigated the electron-beam irradiation effect on solution-grown halide double perovskite Cs2AgBiBr6 crystals by TEM, revealing two different types of electron beam irradiation damage depending on the orientation of Cs2AgBiBr6. When irradiated along the [110](pc) zone axis, a new phase Cs2Ag0.5BiBr6 with a vacancy-ordered superstructure is formed via the knock-on displacement mechanism, while irradiation along the [111](pc) zone axis results in the gradual generation of an amorphous phase through the radiolysis mechanism.
JOURNAL OF PHYSICAL CHEMISTRY C
(2021)
Article
Chemistry, Multidisciplinary
Hamza Shaili, Elmehdi Salmani, Mustapha Beraich, Mustapha Zidane, M'hamed Taibi, Mustapha Rouchdi, Hamid Ez-Zahraouy, Najem Hassanain, Ahmed Mzerd
Summary: This paper presents a comprehensive study on the properties of spray-coated CaSnO3 thin films on Si(100) substrates, as well as the effects of Nd3+ doping and substrate on film characteristics. The research reveals that increasing doping levels enhance the conductivity of the films and grain size, leading to structural changes in the crystals.
Article
Chemistry, Physical
Xiaowei Jia, Xianchun Liu, Ruyu Zhang, Anqi Xie, Yueran Li, Xiaodan Yu, Min Yu, Yunfeng Li, Zhan Shi, Yan Xing
Summary: A series of Fe-doped KCuTa3O9 (FKCTO-x) oxides were synthesized via one-step high-temperature solid-state reaction. Fe atoms were successfully incorporated into the lattice of KCuTa3O9. The FKCTO-x samples showed enhanced photocatalytic hydrogen evolution activities, with FKCTO-2 exhibiting an optimal hydrogen production rate of 5.51 mu mol h-1 under visible light irradiation, far exceeding that of the pure KCTO. This work provides a simple and effective strategy to design and prepare highly efficient visible-light-driven PLMOs for photocatalytic water splitting.
JOURNAL OF ALLOYS AND COMPOUNDS
(2023)
Article
Nanoscience & Nanotechnology
Yoshiyuki Murakami, Fumitaka Ishiwari, Kazumasa Okamoto, Takahiro Kozawa, Akinori Saeki
Summary: The impact of EB radiation on the performance of PSCs was studied, revealing a decrease in power conversion efficiency while the photoconductivities of individual layers remained intact. Significant dedoping of the HTM layer was observed, which could be partially restored through exposure to short-wavelength light. This study demonstrates the resilience of perovskite against EB and sheds light on the degradation mechanism of overall PSC performance.
ACS APPLIED MATERIALS & INTERFACES
(2021)
Article
Chemistry, Physical
Brandon K. Durant, Hadi Afshari, Satyabrata Singh, Bibhudutta Rout, Giles E. Eperon, Ian R. Sellers
Summary: The study found that mixed organic-inorganic halide perovskite solar cells show relatively high tolerance to high-energy proton radiation, and an unexpected increase in open circuit voltage and power density is observed when proton energy is increased.
ACS ENERGY LETTERS
(2021)
Article
Materials Science, Multidisciplinary
Anamul H. Mir, Neil C. Hyatt, Stephen E. Donnelly
Summary: Different types of glass-ceramic composites are being studied as potential matrices for nuclear waste conditioning, with accelerated irradiation tests simulating He accumulation and bubble formation. The use of TEM allows for detailed analysis of the behavior of He in these materials. Various parameters affecting He accumulation and bubble formation are considered in the context of nuclear waste disposal.
JOURNAL OF NUCLEAR MATERIALS
(2021)
Article
Materials Science, Multidisciplinary
A. Diver, O. Dicks, I. T. Todorov, A. M. Elena, K. Trachenko
Summary: The study reports the effects of radiation damage in the nuclear waste form zirconolite, focusing on the differences in response between amorphous and crystalline structures. It suggests that repeated radiation damage can lead to structural evolution in amorphous zirconolite, potentially reaching a new equilibrium state. The correlation between enthalpy changes and local coordination indicates a quantitative link between enthalpy and structural radiation damage.
JOURNAL OF NUCLEAR MATERIALS
(2021)
Article
Materials Science, Multidisciplinary
Zhao Sun, Peng Lv, Zuojiang Wang, Yuzhe Jiang, Yejun Zhao, Wenmin Deng, Shuo Zhang, Limin Zhang, Tieshan Wang, Liang Chen
Summary: The co-doping effects of gadolinium and cerium in zirconolite glass-ceramics were systematically investigated. The results showed that gadolinium could be well incorporated in cerium-bearing zirconolite particles and its doping concentration affected the structure of zirconolite. Furthermore, the doping of gadolinium also influenced the redox state of cerium.
JOURNAL OF NUCLEAR MATERIALS
(2022)
Article
Chemistry, Physical
Yogesh Kumar, S. Tripathi, Mangla Nand, R. Jangir, V. Srihari, A. Das, R. Singh, U. Deshpande, S. N. Jha, A. Arya
Summary: This study investigated the effect of Nd doping on the structural, optical, and electronic properties of lanthanum monazite structure. Pure and Nd-doped LaPO4 powders were prepared and analyzed for their composition, oxidation states, crystal structure, and bandgaps. The results confirmed the successful substitution of Nd in the LaPO4 matrix and provided insights into the local structure using extended X-ray absorption fine structure analysis.
JOURNAL OF ALLOYS AND COMPOUNDS
(2022)
Article
Materials Science, Multidisciplinary
Shuaida Zhu, Xiong Cao, Xiaoqing Cao, Yuqi Feng, Xinbing Lin, Kehua Han, Xiaoxia Li, Peng Deng
Summary: In this study, the effect of M-doped graphitic carbon nitride on the thermal decomposition of DAP-4 was investigated. Fe-g-C3N4 exhibited the best catalytic activity for the thermal decomposition of DAP-4 among the tested catalysts, significantly improving the thermal decomposition parameters. This finding may offer a new perspective for the application of DAP-4 in the field of solid rocket propellants.
MATERIALS & DESIGN
(2021)
Article
Chemistry, Physical
Sen Lian, Lei He, Congcong Li, Junfeng Ren, Lei Bi, Meina Chen, Zijing Lin
Summary: The perovskite/Ruddlesden-Popper oxide heterostructure (Nd,Sr)CoO3 (NSC113)/(Nd,Sr)2CoO4 (NSC214) has been found to significantly enhance the oxygen reduction reaction (ORR) activity due to two main factors: enhanced oxygen adsorption and accelerated transport of interstitial oxygen. Additionally, the perovskite/double-layered R-P oxide heterostructure is predicted to exhibit better ORR performance compared to the perovskite/single-layered R-P oxide heterostructure. This work provides important insights into the atomic-level mechanism of ORR enhancement on perovskite/R-P oxide heterostructures, which is highly significant for the development of high-performance electrochemical devices.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2023)
Article
Materials Science, Multidisciplinary
Xiaoyu Ding, Jiahui Fang, Qiu Xu, Panpan Zhang, Haojie Zhang, Laima Luo, Yucheng Wu, Jianhua Yao
Summary: Carbide-doped materials W-1wt%TiC and W-1wt%ZrC were prepared using a combination of wet chemical method and spark plasma sintering. The microstructural evolution of these materials under He+ irradiation was investigated by TEM. It was found that W-1wt%TiC had higher dislocation loop number density but smaller average loop size compared to W-1wt%ZrC. Both materials exhibited higher radiation resistance to He+ than pure W, with no observable helium bubbles. He+ pre-irradiation increased the D-2 retention of W-1wt%TiC and W-1wt%ZrC.
Article
Chemistry, Inorganic & Nuclear
Lewis R. Blackburn, Luke T. Townsend, Sebastian M. Lawson, Amber R. Mason, Martin C. Stennett, Shi-Kuan Sun, Laura J. Gardner, Ewan R. Maddrell, Claire L. Corkhill, Neil C. Hyatt
Summary: This study comprehensively investigates the incorporation of Dy3+ in the zirconolite solid solution, revealing different phase structures at varying Dy concentrations. The presence of Dy as Dy3+ in the zirconolite matrix, similar to Am3+, was confirmed. Furthermore, the study demonstrates that the addition of Dy leads to the formation of zirconolite-4M and pyrochlore polytype phases.
INORGANIC CHEMISTRY
(2022)
Article
Chemistry, Physical
Mariana Gutierrez, Mathieu Morcrette, Laure Monconduit, Yohan Oudart, Pierre Lemaire, Carine Davoisne, Nicolas Louvain, Raphael Janot
Summary: This study used carbon-coated silicon nanoparticles to prepare Si/C composites with different silicon contents, and demonstrated the clear improvement of electrochemical performances by adding graphite. The degradation phenomena of the anodes while cycling with NMC622 were also observed.
JOURNAL OF POWER SOURCES
(2022)
Article
Materials Science, Ceramics
Doni Daniel Jayaseelan, S. Pramana, S. Grasso, Y. Bai, S. Skinner, M. J. Reece, W. E. Lee
Summary: In this study, single-phase Hf2Al4C5 ternary carbide was fabricated using pressure assisted sintering techniques and its properties were investigated at different temperatures. The results showed that Hf2Al4C5 started to form at relatively low temperatures and fully formed after reactive sintering for a certain period of time. The thermal conductivity of Hf2Al4C5 was measured to be good at high temperatures. The oxidation study revealed that Hf2Al4C5 exhibited good oxidation resistance at high temperatures and had favorable interface bonding characteristics.
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
(2022)
Article
Energy & Fuels
Jack A. Wilson, Lee J. Evitts, Alberto Fraile, Roy E. Wilson, Michael J. D. Rushton, David T. Goddard, William E. Lee, Simon C. Middleburgh
Summary: In this study, the thermal expansion behavior of equiatomic alloys in the Mo-Nb-Ta-Ti-W system was investigated using atomic-scale modeling techniques. The results showed that these techniques can reliably predict the thermal expansion behavior of high entropy alloys and concentrated solid solutions.
JOURNAL OF PHYSICS-ENERGY
(2022)
Article
Nuclear Science & Technology
Mustafa J. Bolukbasi, Simon C. Middleburgh, Scott Vrtiska, William E. Lee
Summary: Improvements in fuel efficiency and economy are crucial for nuclear power reactors. Burnable absorbers (BA) are being developed to enhance fuel cycle flexibility and mitigate performance drawbacks. This study investigates a novel concept - Discrete Burnable Absorber Pins (DBAP) containing ZrB2 and UB2, which show great potential for fuel efficiency and economy. It is observed that the use of DBAP leads to increased reactivity at the end of fuel life due to changes in Pu-239 breeding near the BA.
PROGRESS IN NUCLEAR ENERGY
(2022)
Article
Materials Science, Ceramics
Phylis Makurunje, Simon C. Middleburgh, William E. Lee
Summary: This review discusses various approaches to address the high processing temperatures required in reactive melt infiltration (RMI) processing of modern multiphase ceramic matrix composites (CMCs). It focuses on using immiscible phases, miscible phases, silicide phases, and/or silicide eutectics to lower the temperature requirement for RMI, optimizing the composition of incorporated phases, minimizing damage to reinforcing phases, utilizing rapid heating techniques, and developing in situ real-time monitoring systems. Future opportunities include integrating additive manufacturing with RMI, utilizing process modeling, and applying in situ and in operando characterization techniques.
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
(2023)
Article
Chemistry, Physical
Helene Tonnoir, Da Huo, Carine Davoisne, Alain Celzard, Vanessa Fierro, Damien Saurel, Mimoun El Marssi, Manal Benyoussef, Philippe Meunier, Raphael Janot
Summary: This study focuses on investigating the sodiation mechanism of non-graphitizing carbons (NGC), and reveals that increasing the pyrolysis temperature leads to NGCs with a more ordered structure and developed closed microporosity. In situ Raman spectroscopy shows that the intercalation of Na+ between the graphene layers occurs mainly during the sloping part of the galvanostatic profile, while the plateau at low voltage can be associated with the filling of micropores with sodium.
Review
Physics, Multidisciplinary
Chris Jeynes
Summary: There is currently great interest in studying non-Hermitian Hamiltonian systems, which include various dissipative real systems. These systems can be characterized by a phase parameter that determines how exceptional points influence the system. This article briefly reviews these systems and highlights their geometric thermodynamics properties.
Article
Materials Science, Multidisciplinary
Megan W. Owen, Michael W. D. Cooper, Michael J. D. Rushton, Antoine Claisse, William E. Lee, Simon C. Middleburgh
Summary: UO 2 fuel pellets are often doped with chromium oxide to improve their properties. The low solubility of chromium in UO 2 can lead to segregation of Cr ions to the grain boundary, affecting the material and operational properties of the fuel pellet. This study investigates the structure and diffusion behavior of undoped and Cr doped UO 2 systems using molecular dynamics methods, and highlights the importance of additives in retaining fission products and other migratory species.
JOURNAL OF NUCLEAR MATERIALS
(2023)
Article
Chemistry, Multidisciplinary
Yongshan Tan, Laura J. Gardner, Brant Walkley, Oday H. Hussein, Hao Ding, Shikuan Sun, Hongfa Yu, Neil C. Hyatt
Summary: The effect of ultrafine fly ash (UFA) and fly ash (FA) on the physical properties and micro-structure of magnesium potassium phosphate cement (MKPC) was studied. UFA addition did not affect the hydration peak of MKPC formation but led to increased reaction duration and potential formation of secondary reaction products. The addition of a UFA:FA blend delayed the hydration and setting time of MKPC. MgKPO4 center dot 6H2O was the main crystalline phase observed, but Mg2KH(PO4)2 center dot 15H2O was also observed at low replacement levels in the UFA-only system. UFA and UFA:FA acted as fillers and diluents. The optimized formulation with 40 wt % fly ash (10 wt % UFA and 30 wt % FA) achieved the highest compressive strength and fluidity, producing a dense microstructure.
ACS SUSTAINABLE CHEMISTRY & ENGINEERING
(2023)
Article
Materials Science, Ceramics
Merve Kuman, Laura J. Gardner, Lewis R. Blackburn, Martin C. Stennett, Neil C. Hyatt, Claire L. Corkhill
Summary: In this study, a ceramic wasteform with dual-substituted zirconolite composition was successfully fabricated by hot isostatic pressing. The optimal milling parameters for the zirconolite phase synthesis were determined, leading to improved microstructure properties and higher yield.
CERAMICS-SWITZERLAND
(2023)
Article
Nanoscience & Nanotechnology
Megan W. Owen, Michael J. D. Rushton, Michael W. D. Cooper, E. M. Ghardi, Antoine Claisse, William E. Lee, Simon C. Middleburgh
Summary: Configurational entropy has been calculated to determine its role in stabilizing the amorphous structure of SiO2. Various atomic scale modeling methods were used to assess the structures of crystalline and amorphous SiO2, and the associated configurational entropy was computed at different temperatures. Together with the enthalpy terms from density functional theory, a reliable method for evaluating the stability of crystalline and amorphous structures has been proposed for future studies on dopants, glass forming additives, and radiation damage. Future work will consider the contribution of vibrational entropy to complete the assessment of amorphization.
SCRIPTA MATERIALIA
(2023)
Article
History & Philosophy Of Science
Chris Jeynes, Michael C. Parker, Margaret Barker
Summary: Physics has always been considered as truly representing reality and its foundations are established using philosophical ideas. The naming of physical entities plays a significant role in the acceptance of physical theories. Using the example of thermodynamics, it is demonstrated that the epistemology and ontology of physics ultimately depend on poetic language. Our understanding of the world relies on natural language designed to express meaning and knowledge must be based on intuition.
Article
Materials Science, Multidisciplinary
Claire L. Corkhill, Colleen Mann, Jeremy R. Eskelsen, Donovan N. Leonard, Lucy M. Mottram, Martin C. Stennett, Jennifer M. S. Ayling, Clare L. Thorpe, Max R. Cole, Sarah Nicholas, Ryan Tappero, Eric M. Pierce
Summary: The mechanisms and kinetics of corrosion of a Mg-rich alkali aluminoborosilicate glass simulating UK high-level waste were investigated during dissolution in synthetic cement solutions. The dissolution process varied with the pH and alkaline earth content of the cement solutions. High resolution microscopy and spectroscopy techniques provided insights into the interface between the glass and the cement solutions. Different reaction products and precipitation phases were observed. These findings are important for the final disposition of radioactive waste glasses.
NPJ MATERIALS DEGRADATION
(2022)
Article
Chemistry, Physical
Neelam Ghanshyam Yadav, Nicolas Folastre, Mickael Bolmont, Arash Jamali, Mathieu Morcrette, Carine Davoisne
Summary: This study investigates the utilization of sulfide-based solid electrolytes in Li metal-based all-solid-state batteries, revealing the substantial impact of solid electrolyte structure on the mechanical behavior, stress distribution, and failure mechanisms of the batteries.
JOURNAL OF MATERIALS CHEMISTRY A
(2022)
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)
