Nuclear Materials and Energy最新文献

{"title":"A percolation theory-based approach for analyzing fluid flow mechanism in blanket pebble beds","authors":"Ziyang Wang ,&nbsp;Xuetao Cui ,&nbsp;Jian Wang ,&nbsp;Mingzhun Lei ,&nbsp;Yuntao Song","doi":"10.1016/j.nme.2025.101961","DOIUrl":"10.1016/j.nme.2025.101961","url":null,"abstract":"<div><div>Blanket pebble beds consist of numerous small-diameter particles, posing significant challenges for traditional simulation methods in terms of modeling accuracy and computational efficiency. To improve simulation performance and broaden research approaches, this study develops a percolation network model to analyze purge gas flow behavior within pebble beds. The model validity is confirmed through comparison with experimental data from the literature. Subsequently, the model is applied to simulate both pebble bed structure and fluid flow characteristics, enabling optimization of the purge gas system design. Compared to conventional methods, the percolation network model significantly enhances computational efficiency in fluid flow simulations. This work presents a novel research methodology and computational tool, demonstrating its potential for investigating transient purge gas flow mechanisms in blanket pebble beds.</div></div>","PeriodicalId":56004,"journal":{"name":"Nuclear Materials and Energy","volume":"44 ","pages":"Article 101961"},"PeriodicalIF":2.3,"publicationDate":"2025-06-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144279733","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"On the melting threshold of toroidal gap edges of ITER divertor tungsten monoblocks under repetitive ELM transients","authors":"K. Paschalidis ,&nbsp;S. Ratynskaia ,&nbsp;P. Tolias ,&nbsp;R.A. Pitts","doi":"10.1016/j.nme.2025.101955","DOIUrl":"10.1016/j.nme.2025.101955","url":null,"abstract":"<div><div>Damage to plasma-facing components from transient heat loads, such as Edge Localized Modes (ELMs), poses a critical challenge for ITER’s tungsten (W) divertor monoblocks (MBs). Under the modified ITER Research Plan, the full actively cooled W divertor will be installed from the outset, while the provisional inertially cooled first wall used during ITER’s Start of Research Operations (SRO) will be replaced by the final, actively cooled variant before DT operation. Thus, damage to the divertor during SRO must be kept to the absolute minimum. This study investigates toroidal gap (TG) edge melting during repetitive Type I ELM loading in the SRO phase, first predicted in Gunn et al. (2017) to occur at much lower energy densities than for the top surface. The focus will be on the planned deuterium H-mode plasmas at half nominal toroidal field (2.65 T) and with plasma currents in the range 5–7.5 MA. Self-consistent 3D heat transfer simulations are performed to determine the ELM fluence thresholds for TG edge melting and assess the impact of ELM mitigation via frequency variation to identify the required mitigation level to minimize the melt damage at the ITER divertor during the SRO discharges. It is found that ELM frequencies above 20 Hz are necessary to completely avoid TG edge melting, even under worst-case assumptions. Moreover, for roughly equivalent conditions to those studied with a more simplified approach in Gunn et al. (2017), we find an approximate 25% lower heat load, which can be considered a reasonable agreement in view of the uncertainties in the ELM energy fluence specification and in the treatment of ion orbit dynamics in the gap vicinity.</div></div>","PeriodicalId":56004,"journal":{"name":"Nuclear Materials and Energy","volume":"44 ","pages":"Article 101955"},"PeriodicalIF":2.3,"publicationDate":"2025-06-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144270877","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Densification Behaviors of Zirconium Carbide with Silicon Additive Produced by Spark Plasma Sintering","authors":"Qisen Ren ,&nbsp;Lixiang Wu ,&nbsp;Yang Liu ,&nbsp;Jun Yan ,&nbsp;Yehong Liao ,&nbsp;Weiming Guo ,&nbsp;Weiqiang Liu","doi":"10.1016/j.nme.2025.101958","DOIUrl":"10.1016/j.nme.2025.101958","url":null,"abstract":"<div><div>Zirconium Carbide (ZrC) is a promising matrix material candidate for Fully Ceramic Microencapsulated (FCM) fuel. Using Spark Plasma Sintering (SPS) and introducing a certain amount of Si as sintering additive can effectively promote the sintering densification process, reduce the sintering temperature, and avoid adverse effects on the microstructure and properties of the matrix and fuel phase during high-temperature sintering process. Adopting SPS process, this article investigates the effects of Si addition, sintering temperature, sintering pressure, and holding time on the density and microstructure of ZrC sample. The results indicate that the sintering temperature and Si addition amount are the key factors affecting the densification of ZrC, while the sintering pressure and holding time have a relatively small impact. The addition of Si could effectively promote the densification procedure during ZrC sintering. Introducing 2.5 wt% of Si increased the maximum densification rate by more than 200 % compared to that of pure ZrC, under sintering condition of 1600 °C/20 MPa/10 min.</div></div>","PeriodicalId":56004,"journal":{"name":"Nuclear Materials and Energy","volume":"44 ","pages":"Article 101958"},"PeriodicalIF":2.3,"publicationDate":"2025-06-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144240537","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effect of hydrogen atoms adsorption on the work function of the LaB6","authors":"Xiaoqiao Liu ,&nbsp;Heng Li ,&nbsp;Yubo Ma ,&nbsp;Xin Zhang ,&nbsp;Jun Hu ,&nbsp;Yuhong Xu ,&nbsp;Guangjiu Lei ,&nbsp;Sanqiu Liu ,&nbsp;Zilin Cui ,&nbsp;Yiqin Zhu ,&nbsp;Xiaolong Li ,&nbsp;Huaqing Zheng ,&nbsp;Shaofei Geng ,&nbsp;Xiaochang Chen ,&nbsp;Haifeng Liu ,&nbsp;Xianqu Wang ,&nbsp;Hai Liu ,&nbsp;Jun Cheng ,&nbsp;Changjian Tang","doi":"10.1016/j.nme.2025.101959","DOIUrl":"10.1016/j.nme.2025.101959","url":null,"abstract":"<div><div>This study employed first-principles density functional theory using CP2K and VASP software to investigate the effects of hydrogen atoms adsorption on the work function of the LaB₆ (001) surface. These results indicate that the most favorable adsorption site for hydrogen atoms is located on the top of the boron atoms in the center of the cell. As the hydrogen atom coverage density increases, the absolute value of the average adsorption energy decreases, while the surface work function gradually increases. The analysis shows that changes in the work function are strongly correlated with variations in dipole moment density, exhibiting a linear relationship. Furthermore, charge transfer induced by LaB₆ substrate deformation, the intrinsic charge carried by the hydrogen adsorbate, and the charge transfer resulting from the interaction between the hydrogen adsorbate and the LaB₆ surface substrate determine the variations in dipole moment. When the hydrogen coverage density is below 8.54 × 10^-2 <span><math><mrow><mi>atoms</mi><mo>/</mo><msup><mrow><mi>Å</mi></mrow><mn>2</mn></msup></mrow></math></span>, its effect on the material’s work function is relatively small, with the work function increasing from 2.14 eV to 2.47 eV. It is expected that this study can serve as a reference and theoretical basis for preliminary explorations into the application of LaB₆ in the NBI system.</div></div>","PeriodicalId":56004,"journal":{"name":"Nuclear Materials and Energy","volume":"44 ","pages":"Article 101959"},"PeriodicalIF":2.3,"publicationDate":"2025-06-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144240536","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Corrigendum to “Microstructural study of the thermal stability of a thermomechanically treated T91 steel by TEM in situ annealing” [Nucl. Mater. Energy 32 (2022) 101213]","authors":"Elvira Oñorbe,&nbsp;Mercedes Hernández-Mayoral,&nbsp;Rebeca Hernández,&nbsp;Marta Serrano","doi":"10.1016/j.nme.2025.101926","DOIUrl":"10.1016/j.nme.2025.101926","url":null,"abstract":"","PeriodicalId":56004,"journal":{"name":"Nuclear Materials and Energy","volume":"43 ","pages":"Article 101926"},"PeriodicalIF":2.3,"publicationDate":"2025-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144255190","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Thermal analysis of the W/Cu flat-type component used as lower divertor target in EAST","authors":"Chunyu He ,&nbsp;Dahuan Zhu ,&nbsp;Baoguo Wang ,&nbsp;Changjun Li ,&nbsp;Binfu Gao ,&nbsp;Yang Wang ,&nbsp;Yi Li ,&nbsp;Chuannan Xuan ,&nbsp;Wenxue Fu ,&nbsp;Rong Yan ,&nbsp;Guoliang Xu ,&nbsp;Rui Ding ,&nbsp;Junling Chen ,&nbsp;EAST Team","doi":"10.1016/j.nme.2025.101954","DOIUrl":"10.1016/j.nme.2025.101954","url":null,"abstract":"<div><div>The tungsten-copper (W/Cu) flat-type component is a promising candidate for plasma-facing components, praised for its flexible heat sink design and cost-effective fabrication. It is considered for the ITER divertor dome section and holds potential for divertor targets for future fusion devices. Since 2021, three types of ITER-like W/Cu flat-type components with chamfer angles of 2.40°, 3.76°, and 5.19° have been installed and tested on the outer horizontal target of the lower divertor in EAST. During plasma operations, some W/Cu flat-type components experienced cracking, melting and exfoliation of tungsten, causing plasma disruptions and even the termination of experiments. To address this, this study uses Fluent to evaluate the melting thresholds of these components based on simulations that consider actual conditions. The key findings are summarized: Firstly, only certain W plates can reach high temperatures because the in-situ heat flux is localized, explaining why damage often occurs only on some specific plates. During leading-edge events, the highest temperatures for both W and oxygen-free copper (OFC) occur near the sides, but W’s maximum temperature is at the edge, while OFC’s is near the edge. The high-temperature area for OFC is larger than that for W, resulting in a more uniform temperature distribution. Secondly, for components with chamfer angles of 3.76° and 5.19°, the heat flux <span><math><mrow><msub><mi>q</mi><mn>0</mn></msub></mrow></math></span> required for OFC to melt is always lower than that for W, meaning OFC melts first. For the 2.40° chamfer, OFC melts first when the incident heat flux angle exceeds 2.5°, while W melts first below this angle. At a 10 MW total heating power, all three components face a melting risk at the maximum incident angle of 5° during EAST operations. Thirdly, a linear relationship was identified between the maximum temperatures of W and OFC under such complex loading conditions, offering a method for monitoring OFC maximum temperature based on the IR measurement of surface W temperature. Moreover, this linear relationship can be extended to other heat sink materials. These results provide valuable guidance for EAST’s plasma operations and offer reference data for the use of W/Cu flat-type components in next-generation devices like ITER and CFETR.</div></div>","PeriodicalId":56004,"journal":{"name":"Nuclear Materials and Energy","volume":"43 ","pages":"Article 101954"},"PeriodicalIF":2.3,"publicationDate":"2025-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144204292","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Study on the annealing and three-point bending fracture behavior of single W fiber-reinforced W composites with multiple interfaces prepared by CVD","authors":"Chuan Wu ,&nbsp;Youping Lu ,&nbsp;Juan Du ,&nbsp;Pan Wen ,&nbsp;Jun Tang ,&nbsp;Tianyu Zhao ,&nbsp;Jiming Chen ,&nbsp;Pinghuai Wang ,&nbsp;Xiang Liu","doi":"10.1016/j.nme.2025.101952","DOIUrl":"10.1016/j.nme.2025.101952","url":null,"abstract":"<div><div>The inherent brittleness of tungsten severely limits its application as plasma-facing materials (PFMs). Tungsten fiber (W_f) reinforced tungsten (W) composites (W_f/W) offer a promising toughening approach for tungsten. However, this toughening method faces significant challenges, such as how to optimize the interface strength and preventing damage to the fiber-reinforced structure. In this study, four types of interfaces (Y, Cr, Y₂O₃, and YSZ) were prepared using magnetron sputtering technology, followed by the fabrication of single W_f-reinforced W composites via chemical vapor deposition (CVD). The fracture behavior of the W_f/W composite before and after the annealing process was investigated through three-point bending tests. The results indicate that the interfaces including yttrium (Y), yttrium oxide (Y₂O₃), and yttria-stabilized zirconia (YSZ) all exhibit weak binding strength, leading to interface debonding during the three-point bending test and resulting in ductile fracture behavior for the composite. In contrast, the chromium (Cr) interface displays a high binding strength and lead to brittle fracture behavior for the composite. After annealing at 1000 °C, the binding strength of Y₂O₃ and YSZ interfaces increases, which causes the brittle fracture behavior of the composite. After annealing at 1600 °C, the Cr interface diffused into the W_f and caused the recrystallization of the W_f. The Y interface underwent melting and solidification, leading to a decrease of the binding strength. The interface strength ranks as follows: Cr &gt; YSZ &gt; Y₂O₃ &gt; Y.</div></div>","PeriodicalId":56004,"journal":{"name":"Nuclear Materials and Energy","volume":"43 ","pages":"Article 101952"},"PeriodicalIF":2.3,"publicationDate":"2025-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144195089","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Corrigendum to “Ion-irradiation effect on swelling and microstructure of BN particle dispersed liquid phase sintering SiC” [Nucl. Mater. Energy 39 (2024) 101666]","authors":"Yansong Zhong ,&nbsp;Baopu Wang ,&nbsp;Zhirui Liu ,&nbsp;Bo Huang ,&nbsp;Tatsuya Hinoki","doi":"10.1016/j.nme.2025.101914","DOIUrl":"10.1016/j.nme.2025.101914","url":null,"abstract":"","PeriodicalId":56004,"journal":{"name":"Nuclear Materials and Energy","volume":"43 ","pages":"Article 101914"},"PeriodicalIF":2.3,"publicationDate":"2025-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144255172","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Dependence of irradiation defects evolution on dose rate and PKA energy spectrum in tungsten","authors":"Wei Zhao ,&nbsp;Yu-Hao Li ,&nbsp;Hui-Zhi Ma ,&nbsp;Yu-Ze Niu ,&nbsp;Zhangcan Yang ,&nbsp;Dmitry Terentyev ,&nbsp;Hong-Bo Zhou ,&nbsp;Guang-Hong Lu","doi":"10.1016/j.nme.2025.101956","DOIUrl":"10.1016/j.nme.2025.101956","url":null,"abstract":"<div><div>Heavy-ion irradiation is considered as an effective method to study the performance of nuclear materials under neutron irradiation, while these two types of experiments show the striking difference in microstructure evolution and thermo-mechanical properties. In this work, taking tungsten (W) as an example, we systematically investigated how dose rate and primary knock-on atom (PKA) energy spectrum affect the evolution of displacement damages in materials using object kinetic Monte Carlo (OKMC) method. It is found that the increase of dose rate promotes the nucleation of vacancy clusters and dislocation loops but inhibits their growth, which is in agreement with the experimental results. This should be attributed to shortened evolution time, which suppresses the migration and dissociation of defects and promotes their nucleation, which can be compensated by the increase of temperature. Accordingly, a modified predictive model has been proposed to characterize the compensatory effect of temperature on different dose rates. However, different from the dose rate, the influence of PKA energy spectrum cannot be compensated by temperature variation, because the high-energy PKAs may generate large and stable defect clusters directly during collision cascade. These results clarify the influence of dose rate and PKA energy spectrum on the evolution of displacement defects in W, and provide valuable insights for assessing the performance of materials under neutron irradiation.</div></div>","PeriodicalId":56004,"journal":{"name":"Nuclear Materials and Energy","volume":"43 ","pages":"Article 101956"},"PeriodicalIF":2.3,"publicationDate":"2025-05-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144154802","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Oxidation behaviour of PM-C26M FeCrAl alloy in low-temperature steam 400 – 900 °C","authors":"Logan Joyce ,&nbsp;Rajnikant V. Umretiya ,&nbsp;Haozheng Qu ,&nbsp;Zhongxia Shang ,&nbsp;Yi Xie","doi":"10.1016/j.nme.2025.101953","DOIUrl":"10.1016/j.nme.2025.101953","url":null,"abstract":"<div><div>Iron-chromium-aluminum (FeCrAl) alloys are the primary candidate for serving as an accident tolerant fuel cladding, replacing zirconium (Zr)-based cladding. This preference stems from the high corrosion resistance under both operating and accident conditions in light water reactors (LWRs). To successfully implement this alloy as a cladding material in LWRs, the corrosion behavior under various conditions needs to be understood. While recent studies have focused on high-temperature steam conditions (&gt;1000 °C) and operating conditions (∼300 °C), there is a notable gap in research exploring the steam temperature range above 300 °C and below 1000 °C. This study specifically investigated the formation of oxide layers on powder metallurgy (PM)-C26M FeCrAl in steam at temperatures ranging from 400 °C – 900 °C. It was found that within the temperature range of 400 °C – 600 °C, a duplex oxide layer emerges, with Fe-oxide in the outer layer and Cr/Al-oxide in the inner layer. At 500 °C, the outer layer consists of α-Fe₂O₃ crystals with Cr/Al-oxides in the inner layer. The initial occurrence of a single oxide layer mostly comprised of alumina (Al₂O₃) is observed at 700 °C, remaining consistent from the 700 °C – 900 °C range. The Al₂O₃ layer is nanocrystalline, but not as thick or as uniform in composition as that observed in high-temperature steam environments. Notably, the Al₂O₃ layer has Fe, Cr, and molybdenum (Mo) precipitates dispersed throughout. Increasing the temperature decreases the presence of these precipitates in the oxide layer, and an increase in either temperature or time results in an increase in the thickness of Al₂O₃ layer.</div></div>","PeriodicalId":56004,"journal":{"name":"Nuclear Materials and Energy","volume":"43 ","pages":"Article 101953"},"PeriodicalIF":2.3,"publicationDate":"2025-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144134606","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}