Journal of Nuclear Materials最新文献_第8页

Effect of salt purity on the corrosion of 316 L SS: Long-term studies in molten FLiNaK and ThF4 - LiF 盐纯度对316lss腐蚀的影响：熔融flink和ThF4 - LiF的长期研究

IF 3.2 2区工程技术 Q3 MATERIALS SCIENCE, MULTIDISCIPLINARY

Journal of Nuclear Materials

Pub Date : 2025-12-19 DOI: 10.1016/j.jnucmat.2025.156398

Nigel Lucas , Richard Woods , Simon Crombleholme , Hruthik Vandanapu , Connor Beer , Jeremie Sobel , Thomas Steenberg , Maulik K. Patel

This study investigated the influence of impurities on the corrosion behaviour of 316 L stainless steel in molten FLiNaK at 600 °C and LiThF at 700 °C for up to 3000 h. Coupons exposed to untreated FLiNaK containing moisture and oxides exhibited significantly higher mass loss compared to those exposed to purified salt. This coincides with the depletion of chromium (Cr) and iron (Fe) from the steel, as confirmed by ICP-OES analysis of post-experiment salts. SEM analysis identified intergranular corrosion as the primary attack mode in untreated FLiNaK, with corrosion depths up to 112 μm. Conversely, coupons exposed to purified FLiNaK displayed excellent corrosion resistance, despite trace levels of metallic impurities detected in the salt. These impurities are believed to originate from the purification process itself and may contribute to a small degree of observed corrosion. The typical mode of grain boundary Cr dissolution was observed in coupons tested in untreated FLiNaK salts, while this was absent in coupons tested in purified FLiNaK salts. Interestingly, XRD analysis identified chromium carbide phases on coupons from purified FLiNaK tests. Similar trends were observed in LiThF salt, where untreated salt resulted in severe corrosion compared to purified salt. Overall, this study highlights the critical role of salt purity in minimizing corrosion of 316 L stainless steel in molten fluoride salts. The data from the present study indicates that a purified molten FLiNaK at 600 °C can be a long-term non-corrosive environment for 316 L stainless steel.

本研究研究了杂质对316l不锈钢在600℃熔融FLiNaK和700℃熔融LiThF中长达3000小时的腐蚀行为的影响。暴露于含有水分和氧化物的未处理的FLiNaK中的薄片比暴露于纯化盐中的薄片表现出明显更高的质量损失。这与铬（Cr）和铁（Fe）从钢中耗竭相吻合，正如实验后盐的ICP-OES分析所证实的那样。SEM分析表明，未处理的FLiNaK的腐蚀主要以晶间腐蚀为主，腐蚀深度可达112 μm。相反，尽管在盐中检测到微量的金属杂质，但暴露于纯化的FLiNaK的薄片显示出优异的耐腐蚀性。这些杂质被认为是来自净化过程本身，并可能导致观察到的小程度腐蚀。在未处理的FLiNaK盐中观察到典型的晶界Cr溶解模式，而在纯化的FLiNaK盐中没有这种模式。有趣的是，XRD分析在纯化的FLiNaK测试中发现了碳化铬相。在锂盐中也观察到类似的趋势，与纯化盐相比，未经处理的盐会导致严重的腐蚀。总的来说，这项研究强调了盐纯度在减少316l不锈钢在熔融氟化物盐中的腐蚀方面的关键作用。本研究的数据表明，在600°C下，纯化的熔融FLiNaK可以成为316l不锈钢的长期无腐蚀环境。

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引用次数: 0

In-situ ion irradiation induced nanograin growth in a spent UO2 fuel 原位离子辐照诱导废UO2燃料中纳米颗粒生长

IF 3.2 2区工程技术 Q3 MATERIALS SCIENCE, MULTIDISCIPLINARY

Journal of Nuclear Materials

Pub Date : 2025-12-19 DOI: 10.1016/j.jnucmat.2025.156394

Sadman Sakib , Yunyuan Lu , Cameron B. Howard , Jatuporn Burns , Mario Matos , Wei-Ying Chen , Sudipta Biswas , Fabiola Cappia , Lingfeng He

This study investigates the irradiation-driven evolution of nanograins in the early-stage restructured rim region of medium burnup spent uranium dioxide (UO₂) fuel. Transmission electron microscopy (TEM) lamellas prepared from Belgium Reactor 3 (BR-3) fuel were subjected to in-situ 300 keV Xe ion irradiations under varying doses, fluxes, and temperatures to evaluate their effect on the evolution of the nanograins. Our results reveal that the nanograins grow during ion irradiation. Additionally, the growth is most pronounced at elevated temperatures (300 °C), moderate at room temperature, and negligible at cryogenic temperature (−223 °C). This behavior indicates that thermal activation, alongside irradiation effects, is essential to overcome grain boundary pinning by fission gas bubbles, metallic precipitates, and porosity. Furthermore, while nanograins (<200 nm) consistently coarsened under irradiation, larger grains did not undergo further restructuring, which can be attributed to the strong defect annihilation at TEM lamella surfaces combined with the limited electronic stopping power of low energy Xe ions used in this work. These findings highlight the roles of thermal spike effects, defect mobility, and impurity pinning in governing grain evolution in the rim region of spent UO₂ fuel during ion irradiation, providing key insights for predictive models of restructuring and performance of the high burnup nuclear fuel.

本文研究了中燃耗二氧化铀（UO2）乏燃料早期重构边缘区纳米颗粒的辐照驱动演化。利用比利时三号反应堆（BR-3）燃料制备的透射电子显微镜（TEM）薄片，在不同剂量、通量和温度下进行300 keV Xe离子原位辐照，以评估其对纳米颗粒演化的影响。结果表明，纳米颗粒在离子辐照下生长。此外，在高温（300°C）下生长最明显，在室温下生长适中，在低温（- 223°C）下可以忽略不计。这种行为表明，热活化和辐照效应对于克服由裂变气泡、金属沉淀和孔隙造成的晶界钉住是必不可少的。此外，虽然纳米颗粒（< 200nm）在辐照下不断变粗，但较大的颗粒没有进行进一步的重组，这可以归因于TEM片层表面的强缺陷湮灭，以及本研究中使用的低能Xe离子的有限电子停止能力。这些发现强调了热尖峰效应、缺陷迁移率和杂质钉住在离子辐照过程中控制废UO2燃料边缘区域晶粒演化中的作用，为高燃耗核燃料的重构和性能预测模型提供了关键见解。

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引用次数: 0

Inducing δ-ferrite in 316NG austenitic stainless steel without welding: Microstructure and SCC resistance in simulated BWR environment 316NG奥氏体不锈钢不焊接诱导δ-铁素体：模拟BWR环境下的显微组织和抗SCC性能

IF 3.2 2区工程技术 Q3 MATERIALS SCIENCE, MULTIDISCIPLINARY

Journal of Nuclear Materials

Pub Date : 2025-12-17 DOI: 10.1016/j.jnucmat.2025.156383

Zhao-Wei Fu, Hiroshi Abe, Yutaka Watanabe

This study aims to develop a stainless-steel microstructure with enhanced resistance to stress corrosion cracking propagation in high-temperature water by uniformly distributing island shaped δ-ferrite along grain boundaries. A partially melted zone near the fusion boundary was reproduced through weld-simulation heat treatments to investigate the formation behavior of δ-ferrite. The key material factors and optimal heat treatment conditions required to obtain a microstructure with uniformly and widely distributed island-shaped δ-ferrite along grain boundaries were examined. Crack growth tests were then conducted in a simulated boiling water reactor environment to evaluate the effect of δ-ferrite on crack propagation. The effect of the δ-ferrite on the crack growth rate was not clear. This was attributed to the low crack growth rate and the insufficient distribution of δ-ferrite along the crack propagation path. An investigation of all secondary cracks observed in the cross sections that encountered δ-ferrite revealed that, although the volume fraction of δ-ferrite along the total crack length was extremely small, >50% of the crack tips were located at δ-ferrite. This result suggests that δ-ferrite possesses resistance to crack propagation.

本研究旨在通过沿晶界均匀分布岛状δ铁素体，建立一种耐高温水中应力腐蚀裂纹扩展的不锈钢组织。通过模拟焊接热处理重现了熔合边界附近的部分熔化区，研究了δ-铁氧体的形成行为。研究了获得沿晶界均匀分布的岛状δ铁素体组织所需的关键材料因素和最佳热处理条件。在模拟沸水反应堆环境下进行了裂纹扩展试验，以评估δ-铁素体对裂纹扩展的影响。δ-铁素体对裂纹扩展速率的影响不明显。这主要是由于裂纹扩展速率低，δ-铁素体沿裂纹扩展路径分布不充分所致。对遇到δ铁素体的截面上观察到的所有次生裂纹的研究表明，尽管δ铁素体沿裂纹总长度的体积分数非常小，但50%的裂纹尖端位于δ铁素体。这表明δ-铁素体具有抗裂纹扩展的能力。

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引用次数: 0

Tensile properties of co-rolled Zr/U-10Mo fuel at ambient and elevated temperatures Zr/U-10Mo燃料在常温和高温下的拉伸性能

IF 3.2 2区工程技术 Q3 MATERIALS SCIENCE, MULTIDISCIPLINARY

Journal of Nuclear Materials

Pub Date : 2025-12-17 DOI: 10.1016/j.jnucmat.2025.156392

James Zillinger, Jason Schulthess, Randall Scott, Michael Heighes

The United States High Performance Research Reactor (USHPRR) initiative is currently interested in replacing high-enriched uranium fuel in research reactors with high-assay, low-enriched uranium fuel. This work aimed to assist in that mission by providing tensile test data on co-rolled Zr/U-10Mo plates at differing thicknesses (0.285 mm, 0.300 mm, and 0.465 mm) and temperatures (293 K, 473 K, and623 K). Yield strength and ultimate tensile strength values are reported along with an in-depth comparison of how temperature, rolling direction, thickness, and the presence of the Zr-interlayer affect mechanical properties. Results showed that yield strength and ultimate tensile strength in Zr/U-10Mo mini-plates are reduced as temperature increases by approximately 300 MPa from 293 to 473 K, and another 100 MPa from 473 to 623 K. Additionally it was found that with increased temperature, there was less differentiation in fuel necking and delamination behavior, as well as a greater perceived elongation to fracture. The elastic modulus of co-rolled miniplates did not follow the volumetric rule of mixtures in terms of averaged strength and is actually lower than the reported moduli of both Zr and U-10Mo.

美国高性能研究反应堆（USHPRR）倡议目前有兴趣用高含量、低浓度的铀燃料取代研究反应堆中的高浓缩铀燃料。这项工作旨在通过提供不同厚度（0.285 mm， 0.300 mm和0.465 mm）和温度（293 K， 473 K和623 K）的Zr/U-10Mo共轧板的拉伸测试数据来协助该任务。报告了屈服强度和极限拉伸强度值，并深入比较了温度、轧制方向、厚度和zr -中间层的存在对机械性能的影响。结果表明：在293 ~ 473 K温度范围内，Zr/U-10Mo微型板的屈服强度和极限抗拉强度随温度升高而降低约300 MPa，在473 ~ 623 K温度范围内降低约100 MPa；此外，研究还发现，随着温度的升高，燃料颈缩和分层行为的分化程度降低，断裂伸长率提高。在平均强度方面，共轧微型板的弹性模量不符合混合物的体积规律，实际上低于Zr和U-10Mo的模量。

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引用次数: 0

Deformation behavior of Zr-1Sn-0.3Nb-0.3Fe-0.1Cr zircaloy containing heterogeneous grains with low-angle grain boundaries via in-situ EBSD/SEM 原位EBSD/SEM研究含低角晶界非均相Zr-1Sn-0.3Nb-0.3Fe-0.1Cr锆合金的变形行为

IF 3.2 2区工程技术 Q3 MATERIALS SCIENCE, MULTIDISCIPLINARY

Journal of Nuclear Materials

Pub Date : 2025-12-16 DOI: 10.1016/j.jnucmat.2025.156382

Jing Chen , Wanting Chen , Gaoyong Lin , Gang Wang , Mingzhu Li , Rafi Ullah , Ruiqian Zhang , Huiqun Liu

In this study, the deformation behavior of zircaloy was studied via in-situ electron backscatter diffraction observations. A Zr alloy containing heterogeneous grains with a 1:1 low- and large-angle grain boundary ratio that exhibited excellent mechanical properties was examined. The heterogeneous grains and a high fraction of LAGBs are the main reasons for improving work hardening ability and ductility. During the in-situ tensile test, non-basal dislocation slip systems were the main deformation mechanism. The presence of GNDs and KAM distributed within fine grains requires that Zr alloy overcome greater dislocation resistance to undergo plastic deformation when subjected to external forces, increasing the material’s YS and UTS. The non-basal dislocation slips are the main mode of deformation. Some 2nd pyr. 〈c + a〉 slip systems even with relatively low Schmid factor were activated for the coordination of uniform plastic deformation of multiple grains. Grain rotation facilitated collaborative deformation, with the grain orientation shifting from the basal to non-basal slip system as the strain increased. Therefore, the formability potential of Zr alloys can be improved and excellent mechanical properties can be achieved by introducing heterogeneous grain structures and a high fraction of LAGBs, which is crucial for improving the rolling/punching procedures used in the manufacturing of nuclear reactor structural components.

在本研究中，通过原位电子背散射衍射观察锆合金的变形行为。研究了一种低角和大角晶界比为1:1的非均相Zr合金，该合金具有优异的力学性能。非均匀晶粒和高比例的lagb是提高加工硬化能力和塑性的主要原因。在原位拉伸试验中，非基底位错滑移体系是主要的变形机制。分布在细晶粒内的GNDs和KAM的存在，要求Zr合金在外力作用下克服更大的位错阻力进行塑性变形，增加了材料的YS和UTS。非基底位错滑移是主要的变形形式。第二个pyr。< c + a >滑移体系即使具有较低的施密德因子，也被激活以协调多晶粒的均匀塑性变形。晶粒旋转促进了协同变形，随着应变的增加，晶粒取向从基底滑移系统向非基底滑移系统转移。因此，通过引入非均匀晶粒组织和高含量的LAGBs，可以提高Zr合金的成形潜力，并获得优异的力学性能，这对于改进核反应堆结构部件制造中使用的轧制/冲压工艺至关重要。

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引用次数: 0

Impact of PKA energy and spatial correlation of primary damage on irradiation microstructure evolution in iron: An object kinetic Monte Carlo simulation PKA能量和初始损伤空间相关性对辐照铁微观结构演化的影响：一个物体动力学蒙特卡罗模拟

IF 3.2 2区工程技术 Q3 MATERIALS SCIENCE, MULTIDISCIPLINARY

Journal of Nuclear Materials

Pub Date : 2025-12-16 DOI: 10.1016/j.jnucmat.2025.156384

Bowen Zhang , Fengping Luo , Yuxin Liu , Jin Wang , Denghuang Chen , Chenxu Wang , Steven J. Zinkle , Yugang Wang

Object kinetic Monte Carlo (OKMC) simulations were performed to investigate irradiation-induced microstructural evolution in bcc Fe, focusing on the effects of PKA energies of neutrons and the spatial distribution of primary defects. Molecular Dynamics (MD) simulations were applied to generate displacement cascades in a wide range of PKA energies, leading to different defect distributions after primary damage stage. OKMC simulations were conducted from 300 °C to 500 °C with a dose rate from 10^–5 dpa/s to 10^–3 dpa/s and a total dose of 1.0 dpa. The simulation results demonstrate that increasing PKA energy elevates the number density of vacancy and SIA clusters by one to two orders of magnitude while only slightly reducing their average size. The influence of spatial correlations of cascade debris was further investigated by randomizing the defect clusters in the whole simulation box, neglecting their intra-cascade recombination and self-clustering. Results indicate that the absence of spatial correlations significantly underestimates the number density of vacancy and SIA clusters while overestimating their cluster sizes. Notably, these effects weaken with increasing PKA energy, and even diminish at high temperatures and low dose rates. This work provides fundamental insights into the effect of PKA energy on the long-term evolution with a focus on the spatial correlation after primary damage stage and offer novel insights into accurate prediction of long-term microstructural evolution through mesoscopic methods.

采用物体动力学蒙特卡罗（OKMC）模拟研究了辐照诱导bcc Fe的微观结构演变，重点研究了中子的PKA能量和初级缺陷的空间分布的影响。利用分子动力学（MD）模拟，在较大的PKA能量范围内生成了位移级联，导致了初始损伤阶段后缺陷的不同分布。在300°C至500°C范围内进行OKMC模拟，剂量率为10-5 dpa/s至10-3 dpa/s，总剂量为1.0 dpa。模拟结果表明，PKA能量的增加使空位团簇和SIA团簇的数量密度提高了1 ~ 2个数量级，而其平均尺寸仅略有减小。通过对整个模拟盒中的缺陷簇进行随机化处理，忽略它们在串级内的重组和自聚类，进一步研究了串级碎片空间相关性的影响。结果表明，空间相关性的缺失显著低估了空位和SIA集群的数量密度，而高估了它们的集群大小。值得注意的是，这些效应随着PKA能量的增加而减弱，甚至在高温和低剂量率下减弱。这项工作为PKA能量对长期演变的影响提供了基础见解，重点关注初级损伤阶段后的空间相关性，并为通过介观方法准确预测长期微观结构演变提供了新的见解。

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引用次数: 0

Evaluation of damage effects in 304 high-boron austenitic stainless steel under only and simultaneous Fe, He ions irradiation 304高硼奥氏体不锈钢在单一和同时铁、氦离子照射下的损伤效果评价

IF 3.2 2区工程技术 Q3 MATERIALS SCIENCE, MULTIDISCIPLINARY

Journal of Nuclear Materials

Pub Date : 2025-12-14 DOI: 10.1016/j.jnucmat.2025.156378

Jinhua Hao , Peng Zhang , Xi Li , Bin Wang , Zhihui Cai , Lifeng Ma , Xianxiu Mei

The introduction of precipitates into austenitic stainless steel is an effective strategy for improving irradiation resistance. This study employed only and simultaneous Fe, He ions irradiation on 304 high-boron austenitic stainless steel at room temperature and investigated the mechanism of ion irradiation on irradiation-induced defects and mechanical property. Throughout the ion penetration region under different irradiation conditions, both the austenite and TiB₂ phase retained original crystal structure, while the (Fe,Cr)₂B phase underwent a crystal-to-amorphous transformation. Only He ions irradiation generated nanoscale helium bubbles and induced a high density of fine dislocation loops in the damage peak region within the austenitic matrix. Under simultaneous Fe+He ions irradiation, the average size of helium bubbles and the width of helium bubbles layer increased, and at the same time, the incorporation of Fe ions also promoted the coalescence and growth of dislocation loops. The amorphization of the (Fe,Cr)₂B phase after ion irradiation played a dominant role in softening, while the pinning effect of helium bubbles inhibited hardness decrease. Irradiation-induced dislocation loops played a major role in hardening, especially the small and dense dislocation loops induced by only He ions irradiation generated significant hardening effects. Under simultaneous Fe+He ions irradiation, the 304 high-boron stainless steel with diffusely distributed borides exhibited slight softening without evident hardening. The behavior demonstrated superior resistance to irradiation hardening compared to conventional austenitic stainless steel.

在奥氏体不锈钢中引入析出相是提高耐辐照性能的有效方法。本研究采用Fe、He离子对304高硼奥氏体不锈钢在室温下进行单独和同时辐照，研究了离子辐照对辐照缺陷和力学性能的影响机理。在不同辐照条件下，在整个离子穿透区，奥氏体和TiB2相均保持了原有的晶体结构，而（Fe,Cr）2B相则发生了晶向非晶转变。仅He离子辐照就产生了纳米级的氦气泡，并在奥氏体基体的损伤峰区诱发了高密度的精细位错环。在Fe+He离子同时辐照下，氦气泡的平均尺寸和氦气泡层宽度增大，同时Fe离子的掺入也促进了位错环的聚结和生长。离子辐照后（Fe,Cr）2B相的非晶化对软化起主导作用，而氦气泡的钉住作用则抑制了硬度的降低。辐照诱导的位错环在硬化中起主要作用，特别是仅He离子辐照诱导的小而致密的位错环产生了显著的硬化效应。在Fe+He离子同时照射下，硼化物弥散分布的304高硼不锈钢表现出轻微的软化，没有明显的硬化。与传统奥氏体不锈钢相比，该材料具有更好的抗辐照硬化性能。

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引用次数: 0

Research on the regulation mechanism of laser shock peening on SCC performance of thin-walled austenitic welded joints 激光冲击强化对薄壁奥氏体焊接接头SCC性能的调节机理研究

IF 3.2 2区工程技术 Q3 MATERIALS SCIENCE, MULTIDISCIPLINARY

Journal of Nuclear Materials

Pub Date : 2025-12-13 DOI: 10.1016/j.jnucmat.2025.156381

Qianwu Li, Chengtao Li, Jing Wan, Zhaoguang Zhu, Zhilin Chen, Shugang Zhang, Bin Yang, Yuanbin Gui

To address the susceptibility of thin-walled austenitic stainless steel welded joints in nuclear power plants to stress corrosion cracking (SCC) under multi-field coupling environments, this study employs laser shock peening (LSP) technology for surface treatment to enhance their SCC resistance. By controlling LSP parameters, the research achieved redistribution of residual stresses and the construction of gradient nanostructures, effectively suppressing the initiation and propagation of SCC. Experimental results indicate that LSP treatment transforms residual tensile stresses on the welded joint surface into compressive stresses, significantly reducing the driving force for crack propagation. Simultaneously, the formed gradient nanostructure further mitigates stress concentration, thereby enhancing the material’s crack resistance. EDS analysis reveals that LSP treatment induces redistribution of Cr and Ni elements at grain boundaries, increasing precipitation of M₂₃C₆-type carbides. Although local chromium-depleted zones may elevate the risk of microcrack initiation, the strengthening effect of the gradient nanostructure predominantly governs the overall improvement in SCC resistance. Furthermore, optimized LSP parameters for thin-walled structures were established, and a three-stage strengthening model was developed, providing theoretical guidance for selecting optimal process parameters in practical applications. This research offers new technological pathways and theoretical support for enhancing SCC protection in critical thin-walled welded components of nuclear power plants.

针对核电站薄壁奥氏体不锈钢焊接接头在多场耦合环境下易发生应力腐蚀开裂（SCC）的问题，采用激光冲击强化（LSP）技术进行表面处理，提高其抗应力腐蚀开裂能力。通过对LSP参数的控制，实现了残余应力的重新分布和梯度纳米结构的构建，有效抑制了SCC的产生和扩展。实验结果表明，LSP处理将焊接接头表面的残余拉应力转化为压应力，显著降低了裂纹扩展的驱动力。同时，形成的梯度纳米结构进一步减轻了应力集中，从而提高了材料的抗裂性。EDS分析表明，LSP处理导致Cr和Ni元素在晶界处重新分布，增加了m23c6型碳化物的析出。虽然局部缺铬区可能会增加微裂纹萌生的风险，但梯度纳米结构的强化效应主导了抗SCC性能的整体提高。建立了薄壁结构的优化LSP参数，建立了三阶段强化模型，为实际应用中选择最优工艺参数提供了理论指导。本研究为加强核电站关键薄壁焊接构件的SCC保护提供了新的技术途径和理论支持。

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引用次数: 0

Poisitron annihilation study on corrosion-incudced defects in UNS N10003 alloy exposed to tellurium-containing FLiNaK salt unsn10003合金暴露于含碲的FLiNaK盐中腐蚀缺陷的泊电子湮没研究

IF 3.2 2区工程技术 Q3 MATERIALS SCIENCE, MULTIDISCIPLINARY

Journal of Nuclear Materials

Pub Date : 2025-12-13 DOI: 10.1016/j.jnucmat.2025.156377

Hongxia Xu , Bin Leng , Qi Liu , Wei Xu , Jiandang Liu , Bangjiao Ye , Hefei Huang , Xingtai Zhou , Run Ye

Positron annihilation spectroscopy reveals the effect of tellurium on the corrosion behavior of UNS N10003 in FLiNaK salts at 650°C. Te exposure increased mass loss 16-fold (0.48 vs 0.03 mg/cm²), with inductively coupled plasma optical emission spectrometry (ICP-OES) showing elevated Fe and Cr concentrations but depleted Te in the FLiNaK salts. X-ray diffraction (XRD) and scanning electron microscopy (SEM) identified Ni₃Te₂ precipitates at grain boundaries (GBs) and M₆C carbide-matrix interfaces, which induce the τ₃ component in positron annihilation spectra due to void trapping. Coincidence Doppler broadening (CDB) confirmed defect proliferation via elevation of the S-parameter. Ni₃Te₂ precipitates failed to suppress Cr dissolution and accelerated GBs weakening, thereby promoting intergranular cracking or embrittlement.

正电子湮没光谱揭示了碲对UNS N10003在650℃下在FLiNaK盐中的腐蚀行为的影响。暴露使质量损失增加了16倍（0.48 vs 0.03 mg/cm²），电感耦合等离子体光学发射光谱（ICP-OES）显示，FLiNaK盐中的Fe和Cr浓度升高，但Te耗尽。x射线衍射（XRD）和扫描电镜（SEM）在晶界（GBs）和M6C碳化物-基体界面处发现Ni₃Te₂沉淀，由于空穴捕获导致正电子湮没谱中出现τ₃分量。重合多普勒增宽（CDB）通过s参数升高证实了缺陷增生。Ni₃Te₂的析出未能抑制Cr的溶解，反而加速了GBs的弱化，从而促进了晶间开裂或脆化。

引用次数: 0

Early-stage corrosion behavior of amorphous Al2O3 coating on SIMP steel in static lead-bismuth eutectic 静态铅铋共晶中SIMP钢表面非晶Al2O3涂层的早期腐蚀行为

IF 3.2 2区工程技术 Q3 MATERIALS SCIENCE, MULTIDISCIPLINARY

Journal of Nuclear Materials

Pub Date : 2025-12-13 DOI: 10.1016/j.jnucmat.2025.156380

Jiale Huang , Jintao Zhang , Chenfei Cui , Xueli Mao , Xiaodan Fei , Yang Wu , Guo Pu , Haoxuan Zhong , Sijie Liu , Fangfang Ge , Bingsheng Li

This study focused on the early-stage corrosion behavior of the Al₂O₃ coatings. Al₂O₃ coatings were deposited on SIMP steel substrates via magnetron sputtering. Subsequent corrosion experiments were conducted in oxygen-saturated lead-bismuth eutectic (LBE) at 500 °C for 300 h and 500 h, and 600 °C for 300 h, with complementary testing under an oxygen-controlled condition (10⁻⁶ wt.%) at 500 °C for 500 h. The coating exhibited an initial thickness increase after 300 h at 500 °C in oxygen-saturated LBE, followed by a decrease after 500 h. In contrast, under the oxygen-controlled condition, the coating thickness remained nearly unchanged throughout the 500 h exposure. This divergence is attributed to the initial formation and decomposition of PbAl₂O₄ in oxygen-saturated environment, whereas formation of PbAl₂O₄ was suppressed under oxygen-controlled condition. The coating’s maintained corrosion resistance despite phase changes confirms the efficacy of oxygen control and its promise for structural material applications.

本文主要研究了Al2O3涂层的早期腐蚀行为。采用磁控溅射技术在SIMP钢基体上沉积了Al2O3涂层。随后的腐蚀实验在饱和氧铅铋共晶（LBE）中进行，温度为500℃，分别为300 h和500 h， 600℃，300 h，并在500℃的氧气控制条件下（10 - 6 wt.%）进行500 h的补充测试。在饱和氧LBE中，涂层在500℃，温度为300 h后出现初始厚度增加，500 h后下降。涂层厚度在500 h的暴露过程中几乎保持不变。这种差异归因于PbAl2O4在氧饱和环境下的初始形成和分解，而在氧控制条件下PbAl2O4的形成受到抑制。尽管发生了相变，但涂层仍然保持了耐腐蚀性，这证实了氧控制的有效性及其在结构材料应用中的前景。

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引用次数: 0