Nuclear Materials and Energy最新文献

{"title":"High-dose neutron irradiation of beryllium and titanium beryllide: Summary and outlook","authors":"Vladimir Chakin ,&nbsp;Rolf Rolli ,&nbsp;Hans-Christian Schneider ,&nbsp;Ramil Gaisin ,&nbsp;Pavel Vladimirov ,&nbsp;Michael Klimenkov ,&nbsp;Michael Duerrschnabel ,&nbsp;Nikolai Zimber ,&nbsp;Michael Rieth ,&nbsp;Bronislava Gorr ,&nbsp;Francisco A. Hernández ,&nbsp;Dirk Radloff ,&nbsp;Alexander Fedorov ,&nbsp;Milan Zmitko ,&nbsp;Masaru Nakamichi ,&nbsp;Sergey Udartsev","doi":"10.1016/j.nme.2025.101910","DOIUrl":"10.1016/j.nme.2025.101910","url":null,"abstract":"<div><div>The irradiation experiment conducted in the HFR material testing reactor, under conditions simulating the operating environment of the DEMO breeding blanket, along with subsequent post-irradiation examinations (PIEs) of irradiated beryllium-based materials—such as pure beryllium and titanium beryllide—enabled a comparative analysis of their radiation resistance for potential use as neutron multipliers. The PIEs clearly demonstrated the superiority of titanium beryllide over beryllium, particularly in terms of reduced swelling, lower tritium retention, and enhanced mechanical properties at elevated temperatures. As a result, titanium beryllide blocks have been proposed to replace beryllium pebbles in the Helium-Cooled Pebble Bed (HCPB) DEMO breeding blanket design. A production technology for fabricating titanium beryllide blocks was successfully developed, and further advancements in this technology, along with research on full-scale blocks, have been outlined.</div></div>","PeriodicalId":56004,"journal":{"name":"Nuclear Materials and Energy","volume":"42 ","pages":"Article 101910"},"PeriodicalIF":2.3,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143526815","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Atomic determination of the energetics and configurations of N-Cr/Cr-N-C-O and N-Cr/Ni-vacancy complexes in austenitic Fe alloys","authors":"Guofeng Li ,&nbsp;Pengbo Zhang ,&nbsp;Haichuan Ji ,&nbsp;Mingliang Wei ,&nbsp;Tingting Zou ,&nbsp;Yichao Wang","doi":"10.1016/j.nme.2025.101909","DOIUrl":"10.1016/j.nme.2025.101909","url":null,"abstract":"<div><div>The energetics and configurations of small N-Cr/Cr-N-C-O and N-Cr (Ni)-vacancy complexes in austenitic Fe alloys were investigated using a first-principles method. The interaction between N and Cr/vacancy is attractive (0.10/0.59 eV) while Ni/O repels N (−0.21/−0.46 eV). Energetically, interstitial N and Cr can form stable Cr<em>_m</em>N<em>_n</em> complexes, the binding energy of the clusters increases from 0.24 to 2.07 eV with the size (<em>m</em> = 2–16). The tetrahedral Cr₄N₄ structure acts as a stable unit to form larger size by connecting N (point to point). The presence of Cr strengthens the stability of VN<em>_n</em> clusters energetically while Ni weakens it, the Cr-VN<em>_n</em> and VN<em>_n</em> (<em>n</em> = 1,2) act as main complex defects. Furthermore, we determined the stabilities of serval Cr-N-O/Cr-N-C-O complexes and found that the synergistic interaction of Cr-N-C-O strongly stabilize the clusters and O impurities, then enhancing mechanical properties. Finally, we predicted the effect of Cr/Ni on N migration and effective diffusivity. These results deepen understanding for the synergistic interactions between interstitial N and alloying elements/vacancies in austenitic stainless steels.</div></div>","PeriodicalId":56004,"journal":{"name":"Nuclear Materials and Energy","volume":"42 ","pages":"Article 101909"},"PeriodicalIF":2.3,"publicationDate":"2025-02-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143488668","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effect of Am addition on oxygen potential in (U0.55Pu0.3Am0.15)O2−x","authors":"Keisuke Yokoyama ,&nbsp;Masashi Watanabe ,&nbsp;Akane Usui ,&nbsp;Takayuki Seki ,&nbsp;Takashi Onishi ,&nbsp;Masato Kato","doi":"10.1016/j.nme.2025.101908","DOIUrl":"10.1016/j.nme.2025.101908","url":null,"abstract":"<div><div>Oxygen potential measurement was conducted at 1273 K, 1473 K, 1573 K, and 1623 K for (U_0.55Pu_0.3Am_0.15)O_2−x using a thermogravimeter and oxygen sensors. Adding 15% Am instead of U increased the oxygen potential of (U_0.7Pu_0.3)O_2−x by 100 – 150 kJ/mol. The measured oxygen potentials were analyzed by the defect chemistry method. This analysis showed that the oxygen potential of (U_0.55Pu_0.3Am_0.15)O_2−x was formulated as a function of O/M ratio and temperature, and that the calculated results were consistent with the measured data. The cation valence is estimated to be (U⁴⁺_0.4U⁵⁺_0.15Pu⁴⁺_0.3Am³⁺_0.15)O_2.00 in the stoichiometric composition.</div></div>","PeriodicalId":56004,"journal":{"name":"Nuclear Materials and Energy","volume":"42 ","pages":"Article 101908"},"PeriodicalIF":2.3,"publicationDate":"2025-02-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143488667","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Towards improved neutral exhaust in the HSX stellarator","authors":"Dieter Boeyaert ,&nbsp;Kelly A. Garcia ,&nbsp;Heinke Frerichs ,&nbsp;Michael J. Gerard ,&nbsp;Aaron Bader ,&nbsp;Robert Davies ,&nbsp;Benedikt Geiger ,&nbsp;John Schmitt ,&nbsp;Oliver Schmitz","doi":"10.1016/j.nme.2025.101874","DOIUrl":"10.1016/j.nme.2025.101874","url":null,"abstract":"<div><div>To improve our knowledge of neutral exhaust in non-resonant divertors, a particle exhaust study is performed for the Helically Symmetric eXperiment (HSX). The chaotic magnetic field topology in the plasma edge is examined with connection lengths and Lyapunov exponents. Plasma flux tubes are identified and these flux tubes deposit particles onto plasma facing components. This helps determine the areas where neutrals are generated and provides guidance on where to put baffles. As shown using EMC3-EIRENE simulations, the introduction of baffles can help increase the neutral pressure at and away from the strike line locations. Furthermore, it is demonstrated that baffle design cannot only be based on placing structures at locations with small connection lengths.</div></div>","PeriodicalId":56004,"journal":{"name":"Nuclear Materials and Energy","volume":"42 ","pages":"Article 101874"},"PeriodicalIF":2.3,"publicationDate":"2025-02-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143474695","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effects of 14 T high magnetic field on the formation and migration behavior of CLF-1 steel corrosion products","authors":"Shu-Feng Zhang ,&nbsp;Yi-Ming Lyu ,&nbsp;Lei Peng ,&nbsp;Shan-Liang Zheng","doi":"10.1016/j.nme.2025.101906","DOIUrl":"10.1016/j.nme.2025.101906","url":null,"abstract":"<div><div>The CLF-1 steel, which is a main candidate material of cooling water pipes in fusion reactor blanket being developed in China, is not only corroded by water, but also operates in high magnetic fields. The effect of magnetic field on the corrosion process of CLF-1 steel should be considered. Currently, the corrosion of fusion reactor materials in high magnetic fields at scales of 10 T has not been studied due to the lack of suitable experimental conditions for high magnetic fields. To study the influence of high magnetic fields on the corrosion process of CLF-1 steel, corrosion experiment was carried out using a superconducting steady-state magnet in 1 wt% H₂O₂ + 0.1 wt% NaCl solution for 2 h with the 14 T high magnetic field. A contrast experiment without the magnetic field was performed. The ANSYS software was used to simulate the distribution of magnetic flux around the sample in a 14 T magnetic field. The morphology of the samples was observed and the composition of corrosion products was analyzed. The number of corrosion pits on the sample surface increases significantly at 14 T magnetic field, and the surface corrosion products around the pits appear approximately circular in shape, while the corrosion products distributing in strip shape on sample corroded without the magnetic field. The simulations show that the maximum magnetic flux density is localized in the middle of the sample, where most of the corrosion pits are distributed. Possible reasons for the influence of the magnetic field on the corrosion process could be that the Lorentz force and magnetic gradient force induced change the motion of ions and paramagnetic substances (such as O₂) respectively.</div></div>","PeriodicalId":56004,"journal":{"name":"Nuclear Materials and Energy","volume":"42 ","pages":"Article 101906"},"PeriodicalIF":2.3,"publicationDate":"2025-02-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143465042","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Optimization and evaluation of a water-cooled target probe in linear plasma devices by computational fluid dynamics methods","authors":"Tongzhen Li ,&nbsp;Qian Xu ,&nbsp;Xin Yang ,&nbsp;Fang Ding ,&nbsp;Guang-nan Luo ,&nbsp;Haishan Zhou","doi":"10.1016/j.nme.2025.101905","DOIUrl":"10.1016/j.nme.2025.101905","url":null,"abstract":"<div><div>Effective cooling of the target probe under extreme plasma operational conditions is crucial for ensuring stable and reliable diagnostic measurements. In this study, we designed a water-cooled target probe specifically tailored for deployment in a linear plasma device (LPD). Computational Fluid Dynamics (CFD) methods were employed to evaluate and optimize the cooling performance of the target probe. CFD simulations included different probe base structures and inlet pipe types. The trade-offs between enhanced heat transfer and the associated pressure drop losses for different inlet pipe designs have been comprehensively considered. Simulation results indicated that at a Gaussian heat load of 10 MW/m², which simulates a plasma discharge scenario in the LPD, the maximum temperature of the tungsten probe tip for the optimized target probe was reduced to approximately 723 ℃. Extending the thermal analysis to a future scenario where the target probe is subjected to three adjacent plasma beams, the temperature increase of the tungsten probe tips was not significant. This robust cooling performance highlights the potential of the target probe for application in advanced linear plasma devices that feature multiple or multichannel plasma sources.</div></div>","PeriodicalId":56004,"journal":{"name":"Nuclear Materials and Energy","volume":"42 ","pages":"Article 101905"},"PeriodicalIF":2.3,"publicationDate":"2025-02-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143474696","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effects of liquid metal embrittlement on an alumina forming martensitic steel","authors":"Christopher Petersson ,&nbsp;Peter Szakalos ,&nbsp;Rachel Pettersson ,&nbsp;Mats Lundberg","doi":"10.1016/j.nme.2025.101907","DOIUrl":"10.1016/j.nme.2025.101907","url":null,"abstract":"<div><div>Liquid metal embrittlement was observed in an alumina-forming martensitic (AFM) steel tested in both liquid Pb and lead–bismuth eutectic (LBE) in the temperature range 350–550 °C and 150–550 °C, respectively, using slow strain rate testing (SSRT) in a low oxygen environment (∼10^-11 wt% O dissolved in Pb). A significant decrease in the total elongation to failure (TEF) could be observed in both environments, with LBE yielding the lowest measured TEF of 0.9 % strain at 150 °C. The elongation to failure followed the classic pattern of a ductility dip, gradually recovering with increasing testing temperature so that fully ductile behaviour was restored at 550 °C. There may be a potential to improve the performance of the AFM alloy by optimizing the microstructure through adjustments to the austenitizing, quenching and tempering conditions.</div></div>","PeriodicalId":56004,"journal":{"name":"Nuclear Materials and Energy","volume":"42 ","pages":"Article 101907"},"PeriodicalIF":2.3,"publicationDate":"2025-02-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143454758","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Modified sink strength model for dislocation in tungsten: Dependence on temperature and probability density distribution","authors":"Hui-Zhi Ma,&nbsp;Yu-Hao Li,&nbsp;Yu-Ze Niu,&nbsp;Hong-Bo Zhou,&nbsp;Guang-Hong Lu","doi":"10.1016/j.nme.2025.101900","DOIUrl":"10.1016/j.nme.2025.101900","url":null,"abstract":"<div><div>Sink strength, as a fundamental parameter in mean-field approaches, describes the ability of sinks (e.g., dislocation lines) to capture migrating defects and is crucial for simulating the microstructure evolution of irradiation damage in nuclear materials. Here, taking body centered cubic tungsten (W) as an example, we systematically investigate the sink strength of dislocation lines using the object Kinetic Monte Carlo (OKMC) method. It is found that there are noteworthy discrepancies of sink strength between the traditional theoretical expression and OKMC simulations. This should be attributed to two factors, namely temperature and probability density distribution. The former can be derived from a master curve that has already been proposed for 1D to 3D diffusion–reaction kinetics, while the latter can be well described by a modified analytical expression of sink strength for dislocation lines. By incorporating these factors, the discrepancy between theoretical results and OKMC simulations is eliminated. Notably, the results of defect evolution in irradiated W, obtained using the modified sink strength expression, exhibit a greater consistency with experimental observations than those derived from the conventional model. These results provide a better insight into the sink strength model, and have broad implications for understanding and reproducing the microstructure evolution of irradiation defects in materials.</div></div>","PeriodicalId":56004,"journal":{"name":"Nuclear Materials and Energy","volume":"42 ","pages":"Article 101900"},"PeriodicalIF":2.3,"publicationDate":"2025-02-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143446038","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"TALIF measurements of atomic deuterium in toroidal divertor simulator NAGDIS-T","authors":"Shin Kajita ,&nbsp;Kota Hiraiwa ,&nbsp;Hirohiko Tanaka ,&nbsp;Ryuki Iwai ,&nbsp;Mitsutoshi Aramaki ,&nbsp;Ryo Yasuhara ,&nbsp;Noriyasu Ohno","doi":"10.1016/j.nme.2025.101898","DOIUrl":"10.1016/j.nme.2025.101898","url":null,"abstract":"<div><div>The behavior of neutral deuterium (D) atoms is important for understanding the physics in the divertor region of nuclear fusion reactors. It is necessary to introduce an active measurement when considering the application to detached plasmas, where recombination processes dominate the processes determining the population distribution. In this work, we have developed a two-photon absorption laser-induced fluorescence (TALIF) system in the toroidal divertor simulator NAGDIS-T to measure D atomic density. The absolute D atomic density was obtained by calibrating the signal with the krypton TALIF signal. The gas pressure and power dependence of the D atomic density is shown. The D atomic density was in the range of 1.6 × 10¹⁸–1.4 × 10¹⁹ m⁻³, and the temperature was estimated to be <span><math><mo>&lt;</mo></math></span>0.4 <span><math><mi>eV</mi></math></span>. The behavior of the D atoms is discussed in terms of the production process.</div></div>","PeriodicalId":56004,"journal":{"name":"Nuclear Materials and Energy","volume":"42 ","pages":"Article 101898"},"PeriodicalIF":2.3,"publicationDate":"2025-02-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143430285","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Experiment-modeling studies comparing energy dissipation in the DIII-D SAS and SAS-VW divertors","authors":"D.M. Thomas ,&nbsp;T. Abrams ,&nbsp;R. Ding ,&nbsp;D. Donovan ,&nbsp;F. Effenberg ,&nbsp;J. Herfindal ,&nbsp;A. Hyatt ,&nbsp;A.W. Leonard ,&nbsp;X. Ma ,&nbsp;R. Maurizio ,&nbsp;A.G. McLean ,&nbsp;C. Murphy ,&nbsp;J. Ren ,&nbsp;M.W. Shafer ,&nbsp;D. Truong ,&nbsp;H.Q. Wang ,&nbsp;J.G. Watkins ,&nbsp;J.H. Yu","doi":"10.1016/j.nme.2025.101903","DOIUrl":"10.1016/j.nme.2025.101903","url":null,"abstract":"<div><div>Recent DIII-D experiments on Small Angle Slot (SAS) divertors have confirmed that a combination of divertor closure and target shaping can enhance cooling across the divertor target and increase energy dissipation, but with significant dependence on B_T (toroidal magnetic field) direction. In these novel divertors, the roles of closure, target shaping, drifts, and scale lengths are all interconnected in optimizing dissipation, with the separatrix electron density n_eSEP being the key parameter associated with the level of dissipation/detachment. After modifying the original flat-targeted graphite SAS to include a V shape with a tungsten coating on the outer side of the divertor (SAS-VW), matched series of discharges were run to compare to detailed SOLPS-ITER modeling. Experimentally, when run as designed with the outer strike point at the slot vertex, SAS-VW requires nearly identical n_eSEP for detachment as the original SAS, with little difference in dissipation for the new geometry. This is in contrast to (1) earlier modeling predictions that a small change of the SAS geometry to a V shape should enhance dissipation at the same n_eSEP for magnetic configurations having better H-mode access (ion B × ∇B drift directed into the divertor), and (2) despite the achievement of significantly higher (2-7x) neutral pressures and compression in the SAS-VW slot. Comparisons of experimental density scans to the most recent SOLPS-ITER modeling with ExB drifts show reasonable agreement for dissipation/detachment onset when using separatrix density as the independent parameter. In order to help understand the discrepancy in modeled vs actual performance for the new configuration, additional measurements varying gas injection location and impurity injection were undertaken. In-slot D₂ gas fueling is more effective (5–22 %) in promoting detachment, in accord with modeling. In-slot impurity injection (N₂ or Ne) can yield 30 % lower core Z_eff and 15 % less confinement degradation after detachment compared to main chamber puffing, as well as relatively lower tungsten leakage from the divertor. Modeling can also reproduce the improved detachment seen as the strike point moves inboard of the slot vertex.</div><div>While we can explain the effects of the most important parameters causing energy dissipation in these slot divertors, it remains that many aspects of their behavior cannot be accurately modeled using state-of-art codes such as SOLPS-ITER. This is of concern for future model-driven designs utilizing similar V-shaped geometries.</div></div>","PeriodicalId":56004,"journal":{"name":"Nuclear Materials and Energy","volume":"42 ","pages":"Article 101903"},"PeriodicalIF":2.3,"publicationDate":"2025-02-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143436679","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}