Article
Materials Science, Multidisciplinary
Liangzhao Huang, Kan Ma, Lisa T. Belkacemi, Marie Loyer-Prost, Estelle Meslin, Elin Toijer, Luca Messina, Christophe Domain, Julien Vidal, Maylise Nastar
Summary: A systematic atom probe tomography study was conducted on dilute Fe-Ni and Ni-Ti model alloys to investigate radiation-induced segregation (RIS). The study revealed fluctuations in solute local concentration and the influence of dislocation loop population size and density on these fluctuations. Additionally, the impact of post-treatment parameters on the extracted segregation profiles was highlighted.
Article
Chemistry, Physical
Merve Gencturk, Abdurrahman Ozturk, Karim Ahmed
Summary: This study presents a comprehensive investigation into the Radiation-Induced Segregation (RIS) phenomenon in Ni-Cr alloys. The influence of various factors on RIS, such as the surface's absorption efficiency, grain size, production bias, dose rate, temperature, and sink density, was systematically studied. The findings reveal the significant impact of production bias on the interaction between point defects and grain boundaries/surfaces, highlighting its crucial role in RIS processes. High temperatures and sink density were found to suppress the severity of RIS.
Article
Materials Science, Multidisciplinary
Chaomin Zhang, Yong Jiang, Yanjun Zhou, Xiuhua Guo, Kexing Song
Summary: Interface structure modeling and first-principles calculations were performed to investigate the segregation behaviors of Zr micro-alloying element at nano-Cr particle interfaces and low-Sigma Cu grain boundaries in CueCreZr alloys. The results showed that Zr can substitute Cu atoms at nano-Cr interfaces with the Nishiyama-Wassermann orientation relation, but not at interfaces with the Kurdjumove-Sachs orientation relation. Zr segregation at low-Sigma grain boundaries greatly improved the binding strength.
JOURNAL OF MATERIALS RESEARCH AND TECHNOLOGY-JMR&T
(2023)
Article
Materials Science, Multidisciplinary
Yuanyuan Wang, Jiajun Zhao, Yuanhai Jiang, Liu Xi, Jijun Zhao
Summary: This study assesses the oxidation susceptibility of UN E5(210) grain boundaries (GBs) decorated with Al, Cr, or Ni using first-principles modeling. The predictions reveal that the low segregation energy of O at the Al-doped GB leads to increased O enrichment, explaining the high O concentration observed in experiments. The Ni-doped GB exhibits formidable antioxidant capability but enhances sensitivity to embrittlement, while the Cr dopant effectively reduces O segregation and improves the cohesive capability of the oxidized GB. This work provides atomic-level insights into the mechanisms of (un)-doped UN GB oxidation, complementing previous experimental analyses.
JOURNAL OF NUCLEAR MATERIALS
(2023)
Article
Materials Science, Multidisciplinary
Aashique A. Rezwan, Daniel Schwen, Yongfeng Zhang
Summary: This study presents a modeling investigation on concurrent grain growth and radiation-induced segregation (RIS) in austenitic Fe-Cr-Ni. The results show that grain growth significantly affects RIS in terms of increasing grain size and motion of grain boundaries as defect sinks. Additionally, RIS in nanocrystalline materials induces grain-level compositional redistribution, resulting in grain-size-dependent compositions in individual grains. These findings highlight the different effects of RIS in nanocrystalline alloys compared to coarse-grained counterparts.
JOURNAL OF NUCLEAR MATERIALS
(2022)
Article
Chemistry, Physical
Ziqi Xiao, Lingfeng He, Xian-Ming Bai
Summary: Thermal annealing or radiation induced segregation of solute and impurity elements to grain boundaries in metallic alloys changes GB chemistry, affecting the cohesive strength. Solute elements show varying effects on GB strength, with C and P causing embrittlement while Cr and Ti strengthening GBs. Detailed chemical interactions between solutes and Ni atoms at GBs play a significant role in determining GB strength.
JOURNAL OF ALLOYS AND COMPOUNDS
(2021)
Article
Materials Science, Multidisciplinary
Mark Fedorov, Jan S. Wrobel, Witold Chrominski, Grzegorz Cieslak, Magdalena Plocinska, Krzysztof J. Kurzydlowski, Duc Nguyen-Manh
Summary: The relative phase stability of fcc and bcc Cr-Fe-Mn-Ni alloys was studied using density functional theory, cluster expansion (CE), and Monte Carlo (MC) simulations. The CE models enabled the calculation of Gibbs free energies of formation for different compositions, and the MC simulations provided insights into the stability of these alloys at different temperatures. The results obtained were in line with experimental data and helped identify the alloys that are predicted to have a single fcc phase over a wide temperature range.
Article
Materials Science, Multidisciplinary
Mark Fedorov, Jan S. Wrobel, Andrew J. London, Krzysztof J. Kurzydlowski, Chu-Chun Fu, Tonci Tadic, Sergei L. Dudarev, Duc Nguyen-Manh
Summary: Using exchange Monte Carlo (MC) simulations based on an ab initio-parameterized Cluster Expansion (CE) model, the phase stability of low-Cr Fe-Cr alloys was explored as a function of vacancy (Vac), carbon, and nitrogen content. It was found that the addition of a small amount of C or N in an alloy without vacancies resulted in the formation of ordered compounds containing high amounts of Cr, C, and N. Cr segregated to interstitial atoms and the concentration of Cr in Cr-rich clusters increased with the concentration of C and/or N. In the presence of vacancies, C and N aggregate to the core regions of vacancy clusters, reducing the segregation of Cr-rich clusters. The structure of Cr-rich clusters varied depending on the concentration of interstitial atoms and the ratio of N to C. The predictions derived from MC simulations were in agreement with experimental observations of Fe-Cr alloys exposed to ion irradiation.
JOURNAL OF NUCLEAR MATERIALS
(2023)
Article
Physics, Multidisciplinary
Fu-Shi Jiang, Wei-Hua Wang, Hong-Ming Li, Qing Wang, Chuang Dong
Summary: In this study, the short range order and physical properties of Ni-Al-Cr alloys were investigated using the cluster-plus-glue-atom model. The results showed that the configurations of the cluster-plus-glue-atoms model were more stable and the bonding between Ni-Al and Ni-Cr was easier. Additionally, the Ni-Al-Cr alloy exhibited conductor properties and strong interactions between Ni and Al atoms as well as Ni and Cr atoms.
ACTA PHYSICA SINICA
(2022)
Article
Materials Science, Multidisciplinary
Lei Wang, Reza Darvishi Kamachali
Summary: This research utilized a density-based model to calculate multi-component grain boundary phase diagrams and studied the Fe-Mn-Cr, Fe-Mn-Ni, Fe-Mn-Co, Fe-Cr-Ni, and Fe-Cr-Co alloy systems. The study found that despite solute segregation enrichment, a grain boundary may have a lower solubility limit than the bulk, promoting interfacial chemical decomposition.
Article
Materials Science, Multidisciplinary
Blas P. Uberuaga, Pauline Simonnin, Kevin M. Rosso, Daniel K. Schreiber, Mark Asta
Summary: This work examines the effect of Cr alloying on mass transport along grain boundaries in Ni. It is found that Cr tends to reduce the rate of mass transport in general, but can greatly enhance atomic mobility in special scenarios. The presence of Cr eliminates grain boundary mobility that is sometimes observed in pure Ni boundaries. These insights provide a better understanding of the role of grain boundary alloying on transport and can contribute to the development of predictive models for materials evolution.
JOURNAL OF MATERIALS SCIENCE
(2022)
Article
Materials Science, Multidisciplinary
Jia-Hong Ke, Benjamin W. Spencer
Summary: This study develops a new precipitation model that couples radiation-induced segregation with precipitation kinetics. The results show that segregation and heterogeneous nucleation play significant roles in the performance of nuclear structural materials under high neutron fluence.
JOURNAL OF NUCLEAR MATERIALS
(2022)
Article
Nanoscience & Nanotechnology
Haruka Shima, Manami Mori, Kenta Yamanaka, Kazuo Yoshida, Toshihiro Yamazaki, Akihiko Chiba
Summary: In this study, significant hardening was achieved in a Co-, Cu-modified Ni-Cr-Mo alloy under appropriate cold swaging/aging conditions, resulting in exceptional hardness (HV599) and improved corrosion performance through nanoscale segregation mechanisms and fine dispersion of Cu precipitates.
SCRIPTA MATERIALIA
(2022)
Article
Materials Science, Multidisciplinary
Ci Wang, Stephan Schonecker, Wei Li, Yaochun Yang, Qing-Miao Hu, Levente Vitos
Summary: Using density-functional theory, we determined the generalized stacking fault energy for the twinning system in Fe and Fe-Cr alloys, showing that the isosceles twin boundary configuration is energetically preferred. The magnetic ordering effects and Cr content have significant influences on the twin boundary formation and migration energies in different magnetic states.
Article
Nuclear Science & Technology
Pengbo Zhang, Tingting Zou, Dan Sun, Yan Yin, Jijun Zhao
Summary: By first-principles calculations, we investigated the interaction of oxygen with alloying elements and vacancies, as well as the migration property of oxygen in dilute austenitic iron alloys. Oxygen prefers to occupy octahedral interstitial sites in the Cr-rich region, with strong attractive interaction with Cr. The interaction with Ni and O itself is repulsive. The interaction between oxygen and vacancies is strong, while the interactions with Cr-vacancy and Ni-vacancy are weak.
FUSION ENGINEERING AND DESIGN
(2021)
Article
Chemistry, Physical
Maciej P. Polak, Ryan Jacobs, Arun Mannodi-Kanakkithodi, Maria K. Y. Chan, Dane Morgan
Summary: Using multi-fidelity datasets and a machine learning approach, we have significantly reduced the time required for predicting impurity transition levels in semiconductors. The model trained on these datasets shows improved accuracy and does not require high-fidelity values, reducing computational cost. This approach has the potential to predict transition levels in various semiconductor materials.
JOURNAL OF CHEMICAL PHYSICS
(2022)
Article
Chemistry, Physical
Ryan Jacobs, Jian Liu, Beom Tak Na, Bo Guan, Tao Yang, Shiwoo Lee, Greg Hackett, Tom Kalapos, Harry Abernathy, Dane Morgan
Summary: The discovery and engineering of new materials with fast oxygen surface exchange kinetics and long-term stability is crucial for the commercialization of solid oxide fuel cell (SOFC) technology. A perovskite catalyst material called BFCZ75, which has a high zirconium content and low conductivity, shows similar oxygen reduction reaction rates as traditional electrode materials and excellent stability at typical operating temperatures. The integration of BFCZ75 with commercial electrode materials like LSCF results in low area specific resistance (ASR) values, making it easier for the potential commercial application of new electrode materials.
ADVANCED ENERGY MATERIALS
(2022)
Article
Chemistry, Physical
Yu-chen Liu, Henry Wu, Tam Mayeshiba, Benjamin Afflerbach, Ryan Jacobs, Josh Perry, Jerit George, Josh Cordell, Jinyu Xia, Hao Yuan, Aren Lorenson, Haotian Wu, Matthew Parker, Fenil Doshi, Alexander Politowicz, Linda Xiao, Dane Morgan, Peter Wells, Nathan Almirall, Takuya Yamamoto, G. Robert Odette
Summary: This study demonstrates the potential benefits and risks of using machine learning models to predict irradiation hardening in LWR pressure vessel steels. By training the model and successful extrapolations, machine learning models can capture key intermediate flux effects at high fluence.
NPJ COMPUTATIONAL MATERIALS
(2022)
Article
Chemistry, Physical
Glenn Palmer, Siqi Du, Alexander Politowicz, Joshua Paul Emory, Xiyu Yang, Anupraas Gautam, Grishma Gupta, Zhelong Li, Ryan Jacobs, Dane Morgan
Summary: This paper presents a calibration method to improve the accuracy of uncertainty estimation in machine learning models. It demonstrates that the direct bootstrap ensemble standard deviation is not an accurate estimate of uncertainty, but can be improved through calibration.
NPJ COMPUTATIONAL MATERIALS
(2022)
Article
Materials Science, Multidisciplinary
Jingrui Wei, Ben Blaiszik, Aristana Scourtas, Dane Morgan, Paul M. Voyles
Summary: The information content of atomic-resolution STEM images can be summarized by a few parameters, with column position being the most significant. Neural networks have been used to automatically locate atomic columns in STEM images, resulting in numerous NN models and training datasets. In this study, a benchmark dataset of simulated and experimental STEM images was developed to evaluate the performance of recent NN models for atom location. The models showed high performance for images of varying quality and crystal lattices. However, they performed poorly for images outside the training data, such as interfaces with large difference in background intensity. The benchmark dataset and models are available through the Foundry service.
MICROSCOPY AND MICROANALYSIS
(2023)
Article
Chemistry, Multidisciplinary
Jun Meng, Mehrdad Abbasi, Yutao Dong, Corey Carlos, Xudong Wang, Jinwoo Hwang, Dane Morgan
Summary: This study characterized the structural and electronic properties of a-TiO2 thin films grown on Si by ALD, revealing the medium-range ordering in the film and establishing a realistic atomic model. Additionally, an improved multi-objective optimization package, StructOpt, was provided for structure determination of complex materials.
Article
Nanoscience & Nanotechnology
Mehrdad Abbasi, Yutao Dong, Jun Meng, Dane Morgan, Xudong Wang, Jinwoo Hwang
Summary: The evolution of medium range ordering (MRO) and crystallization behavior of amorphous TiO2 films grown by atomic layer deposition were investigated using in situ four-dimensional scanning transmission electron microscopy. The degree of MRO increases with temperature and reaches the maximum when crystallization starts to occur. In addition, post-annealing only develops a small portion of MRO into crystal nuclei, while the remaining MRO regions undergo structural relaxation. Crystallographic defects within crystal phases were observed, which may affect the corrosion resistance of the film. Understanding and controlling MRO is important for optimizing ALD-grown amorphous films for future functional devices and renewable energy applications.
Article
Engineering, Electrical & Electronic
Lin Lin, Ryan Jacobs, Dane Morgan, John Booske
Summary: Recent experiments on the perovskite oxide SrVO3 demonstrate the potential for achieving low work functions using surface dipoles on polar perovskites. Additional density functional theory calculations suggest that many other perovskites, including BaMoO3, may also exhibit low work function. In this study, the thermionic emission behavior of BaMoO3 was investigated, showing a temperature limited emission current density that increases and saturates with increasing voltage. The material exhibits an overall effective work function comparable to LaB6, but higher than the lowest work function predicted by DFT. The discrepancy is attributed to patch field effects caused by nanoscale features on individual surface facets. BaMoO3 also exhibits some instability at high temperatures, but shows comparable emission behavior to LaB6 at temperatures below 1200 degrees C, making it a potential vacuum electron source for applications such as electron microscopes and electron beam writers.
IEEE TRANSACTIONS ON ELECTRON DEVICES
(2023)
Article
Engineering, Electrical & Electronic
Dongzheng Chen, Ryan Jacobs, Dane Morgan, John Booske
Summary: In the study of thermionic electron emission, the shape of the Miram curve knee, which represents the transition between the exponential region and the saturated emission regions, plays a crucial role in evaluating the quality of thermionic vacuum cathodes. This research provides a comprehensive understanding of the physical factors, including the space charge effect and the patch field effect, that determine the shape of the knee. By using a model system with a periodic, equal-width striped work function distribution, the study illustrates how these physical effects restrict the emission current density near the Miram curve knee. The results identify three key physical parameters that significantly impact the shape of the Miram curve, providing new insights for the design of thermionic cathodes in vacuum electronic devices.
IEEE TRANSACTIONS ON ELECTRON DEVICES
(2023)
Article
Materials Science, Multidisciplinary
Jianqi Xi, Yeqi Shi, Vitaly Pronskikh, Frederique Pellemoine, Dane Morgan, Izabela Szlufarska
Summary: Using atomistic simulations, we investigated the behavior of helium bubbles in beryllium, focusing on their shape, stability, and diffusivity. We found that helium bubbles become unstable and change shape through plastic deformation when the helium-vacancy ratio exceeds 1.25. The dominant diffusion mechanism of helium bubbles changes from surface diffusion to volume diffusion at around 900 K. The results provide valuable insights into the microstructural evolution and properties of irradiated materials.
JOURNAL OF NUCLEAR MATERIALS
(2023)
Article
Multidisciplinary Sciences
Yutao Dong, Mehrdad Abbasi, Jun Meng, Lazarus German, Corey Carlos, Jun Li, Ziyi Zhang, Dane Morgan, Jinwoo Hwang, Xudong Wang
Summary: Amorphous titanium dioxide (TiO2) film coating by atomic layer deposition (ALD) is a promising strategy to extend the photoelectrode lifetime for solar fuel generation. In this work, it is revealed that residual chlorine (Cl) ligands are detrimental to the silicon (Si) photoanode lifetime. Post-ALD in-situ water treatment effectively improves the film stoichiometry and preserves the amorphous phase, leading to a substantially improved lifetime for the protected Si photoanode.
NATURE COMMUNICATIONS
(2023)
Article
Multidisciplinary Sciences
Ryan Jacobs, Priyam Patki, Matthew J. Lynch, Steven Chen, Dane Morgan, Kevin G. Field
Summary: Accurate quantification of nanoscale cavities in irradiated alloys is achieved using the Mask R-CNN model, which provides insights into alloy performance and swelling metrics. The model demonstrates good performance in terms of statistical and materials property-centric evaluations, enabling accurate assessments of swelling in alloys.
SCIENTIFIC REPORTS
(2023)
Review
Physics, Applied
Lin Lin, Ryan Jacobs, Tianyu Ma, Dongzheng Chen, John Booske, Dane Morgan
Summary: In this review, the authors define different aspects of the work function and discuss the role of electric fields in work-function measurement and interpretation. They review standard experimental approaches and computational tools for measuring and predicting work function, and explore the influence of materials chemistry and structure on work-function trends. The authors also discuss the role of work function in various applications and provide guidance for engineering work-function values.
PHYSICAL REVIEW APPLIED
(2023)
Article
Energy & Fuels
Xiu-Liang Lv, Patrick T. Sullivan, Wenjie Li, Hui-Chun Fu, Ryan Jacobs, Chih-Jung Chen, Dane Morgan, Song Jin, Dawei Feng
Summary: This study successfully synthesized an ionic liquid-mimicking catholyte for aqueous organic redox flow batteries (AORFBs) that demonstrated high performance in terms of stability, power, and energy density. The optimized catholyte showed robust cycling stability, high power density, and high energy density, paving the way for low-cost and scalable AORFBs.
Article
Chemistry, Multidisciplinary
Ziyi Zhang, Maciej P. Polak, Corey Carlos, Yutao Dong, Dane Morgan, Xudong Wang
Summary: Two-dimensional ferromagnetic materials with strong room-temperature ferromagnetism have been synthesized using an ionic layer epitaxy strategy. The ferromagnetic strength of the NiOOH nanosheets can be controlled by adjusting the surfactant monolayer density and annealing process, offering a promising pathway for achieving strong ferromagnetism in two-dimensional materials for spintronic applications.
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)