IF 3.8 2区材料科学 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Vacuum

Pub Date : 2024-11-15 DOI: 10.1016/j.vacuum.2024.113835

Yu Wan, Laimin Song, Xuyang Zhang, Wenchun Jiang, Xuefang Xie, Xinyue Qi

Electron beam welding (EBW) is the preferred technique for joining TC4 titanium alloy. Accurately characterizing the welding keyhole and residual stress distribution, along with analyzing their formation mechanisms, is of paramount importance for ensuring high reliability of the TC4 EBW structures. In this regard, a “thermal-fluid-metallurgical-mechanical” multi-field coupling numerical method was developed, which was then validated by the vital experiments. The evolution of the keyhole, molten pool temperature, phase volume fraction and residual stresses was then revealed. The influencing mechanism of keyhole on residual stress was explored comprehensively. The results show that metal vapor recoil pressure serves as the primary factor in keyhole formation, while the surface tension promotes keyhole closure. The β-phase in the weld zone undergoes a complete transformation into α′ acicular martensite. Moreover, the maximum longitudinal stress occurs at the weld center, while the transverse stress exhibits a substantial stress gradient along the thickness direction. Increasing the welding power raises the temperature of molten pool. The keyhole depth and width are also enlarged, accompanying by the increase of residual stress, which is expected to offer a theoretical foundation for managing the keyhole and residual stress generated during the EBW of TC4 titanium alloy.

电子束焊接（EBW）是连接 TC4 钛合金的首选技术。准确描述焊接锁孔和残余应力分布，并分析其形成机理，对于确保 TC4 EBW 结构的高可靠性至关重要。为此，我们开发了一种 "热-流体-冶金-机械 "多场耦合数值方法，并通过重要实验进行了验证。研究揭示了键孔、熔池温度、相体积分数和残余应力的演变过程。全面探讨了锁孔对残余应力的影响机理。结果表明，金属蒸汽反冲压力是键孔形成的主要因素，而表面张力则促进了键孔的闭合。焊接区的β相完全转变为α′针状马氏体。此外，最大纵向应力出现在焊接中心，而横向应力沿厚度方向呈现出很大的应力梯度。增加焊接功率会提高熔池温度。这有望为 TC4 钛合金 EBW 焊接过程中产生的锁孔和残余应力的管理提供理论依据。

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引用次数: 0

IPFOA-MKSVM and BA-MLP models for predicting closed busbar temperatures in high voltage nuclear power plants in different vacuum environments 用于预测不同真空环境下高压核电站封闭母线温度的 IPFOA-MKSVM 和 BA-MLP 模型

IF 3.8 2区材料科学 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Vacuum

Pub Date : 2024-11-15 DOI: 10.1016/j.vacuum.2024.113825

Zuoxun Wang, Guojian Zhao, Jinxue Sui, Wangyao Wu, Chuanzhe Pang, Liteng Xu

The nuclear power closed busbar is a key power transmission component in the power system, and its high temperature may cause equipment failure. In this paper, for the temperature prediction of nuclear power closed busbar under vacuum environment, a multi-core support vector machine model optimized by the improved falcon predation algorithm and a multi-layer perceptron model enhanced by the back propagation algorithm are proposed. The vacuum pump is used to reduce the air pressure in the closed space to achieve a vacuum state. The collected data are preprocessed to improve the accuracy and stability of the model. In addition, the PSO and SVM models are used to compare and verify the superiority of the proposed model. The data set is divided into a training set and a test set. The results show that under different vacuum degrees, the prediction accuracy and stability of the IPFOA-MKSVM model are better than those of other models, but its error is slightly higher than the physical calculation result. Finally, the performance of the model in wind speed prediction is verified, and compared with several models to verify the accuracy of IPFOA-MKSVM under different vacuum and wind speed conditions.

核电封闭母线是电力系统中的关键输电部件，其温度过高可能导致设备故障。本文针对真空环境下核电封闭母线的温度预测，提出了一种通过改进的猎鹰捕食算法优化的多核支持向量机模型和一种通过反向传播算法增强的多层感知器模型。利用真空泵降低封闭空间内的气压，使其达到真空状态。收集到的数据经过预处理，以提高模型的准确性和稳定性。此外，还使用 PSO 和 SVM 模型来比较和验证所提模型的优越性。数据集分为训练集和测试集。结果表明，在不同真空度下，IPFOA-MKSVM 模型的预测精度和稳定性均优于其他模型，但其误差略高于物理计算结果。最后，验证了该模型在风速预测中的性能，并与多个模型进行了比较，验证了 IPFOA-MKSVM 在不同真空度和风速条件下的准确性。

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引用次数: 0

Martensite instability induced surface hardening on gradient nano-structured 316L stainless steel 梯度纳米结构 316L 不锈钢的马氏体不稳定性诱导表面硬化

IF 3.8 2区材料科学 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Vacuum

Pub Date : 2024-11-14 DOI: 10.1016/j.vacuum.2024.113831

Y.B. Lei , Z.M. Niu , B. Gao , Y.T. Sun

Gradient nanostructured (GNS) 316L stainless steel manufactured by surface mechanical rolling treatment (SMRT) with a full martensitic phase on the surface exhibits an extraordinary annealed hardening. The surface hardness increases by 44 % from 4.1 GPa of the SMRTed 316L stainless steel up to 5.9 GPa after annealed at 400 °C for 120 min. Surface hardening is primarily attributed to the formation of low angle grain boundaries (LAGBs) within the original nano-grains. LAGBs function as substructures that effectively divide the grains into smaller units. These LAGBs originate from lattice distortions caused by Ni segregation during the annealing process. Furthermore, the redistribution of Ni can be regarded as a nucleation step leading to phase reversion from martensite to austenite. Additionally, the presence of Ni-enriched zones distributed within the martensite matrix serves to hinder dislocation movement, thus contributing to the observed surface hardening.

通过表面机械轧制处理（SMRT）制造的梯度纳米结构（GNS）316L 不锈钢表面具有完整的马氏体相，表现出非凡的退火硬化性。经 SMRT 处理的 316L 不锈钢在 400 °C 退火 120 分钟后，表面硬度从 4.1 GPa 提高到 5.9 GPa，提高了 44%。表面硬化的主要原因是在原始纳米晶粒内形成了低角度晶界（LAGBs）。低角度晶界作为一种子结构，可有效地将晶粒分割成更小的单元。这些 LAGB 源于退火过程中镍偏析引起的晶格畸变。此外，镍的重新分布可被视为导致从马氏体到奥氏体相变的成核步骤。此外，分布在马氏体基体中的富镍区阻碍了位错运动，从而导致了观察到的表面硬化。

引用次数: 0

Research on energy loss mechanism and optimization method of liquid ring vacuum pump based on entropy production theory 基于熵产生理论的液环真空泵能量损失机理及优化方法研究

IF 3.8 2区材料科学 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Vacuum

Pub Date : 2024-11-14 DOI: 10.1016/j.vacuum.2024.113833

Huayi Liu , Guoyong Zhao , Shuo Yu , Qingyun Li , Yanjie Li , Fanrui Meng

To solve the problem of high energy consumption of liquid ring vacuum pumps and serious hydraulic losses that make it difficult to improve the efficiency of the pumps. Firstly, the mechanism of the influence of radical clearance on the energy loss of liquid ring vacuum pumps is investigated, and a directional and quantitative analysis of the energy loss in the flow field within a liquid ring vacuum is made based on the entropy production theory. Then the structural parameter control model oriented to the maximum suction capacity and minimum wall effect entropy production of the liquid ring vacuum pump is established. The results indicate that turbulent entropy production and wall entropy production dominate the energy losses of liquid ring vacuum pumps with radial clearance of 24 mm, 28 mm, 32 mm, and 36 mm. The entropy production caused by the wall effect mainly occurs at the shell of the gas compression region. The optimized liquid ring vacuum pump model achieves an increase in suction capacity of 8.74 %, an increase in isothermal compression efficiency of 3.75 %, and a reduction in wall effect entropy production of 19.7 %.

为解决液环真空泵能耗高、水力损失严重，难以提高泵效率的问题。首先研究了激元间隙对液环真空泵能量损失的影响机理，并基于熵产理论对液环真空内流场的能量损失进行了定向定量分析。然后建立了面向液环真空泵最大抽吸能力和最小壁效应熵产生的结构参数控制模型。结果表明，在径向间隙为 24 毫米、28 毫米、32 毫米和 36 毫米的液环真空泵中，湍流熵产生和壁面熵产生在能量损失中占主导地位。壁面效应导致的熵产生主要发生在气体压缩区域的壳体上。优化后的液环真空泵模型吸气能力提高了 8.74%，等温压缩效率提高了 3.75%，壁面效应产生的熵减少了 19.7%。

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引用次数: 0

Self-catalyzed growth of sub-25-nm-diameter InAs nanowire arrays on Si patterned substrate 直径亚 25 纳米 InAs 纳米线阵列在硅图案衬底上的自催化生长

IF 3.8 2区材料科学 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Vacuum

Pub Date : 2024-11-14 DOI: 10.1016/j.vacuum.2024.113832

Xiaoye Wang , Xiaoguang Yang , Tao Yang

The feature size of advanced Si-based chips is approaching its physical limit, and it is difficult to continue Moore's Law by simply pursuing the technical route of miniaturizing device size to increase the integrated density. III-V nanowire devices represented by InAs material have much higher mobility than Si based devices, but they have not been successfully applied to CMOS nanowire devices and have not shown excellent performance. The reason is that the hole mobility of III-V materials is much lower than their electron mobility. If the nanowire diameter becomes ultrafine, the quantum confinement effect becomes more prominent, the light hole band will reverse above the heavy hole band, and the hole mobility will be greatly increased. Aiming at the integrability of III-V high mobility CMOS devices on Si, how to prepare ultrafine InAs nanowire arrays on Si/SiO₂ patterned substrates has been studied in this work. New method in this work has solved the problem that the nanohole will enlarge due to etching side wall of nanohole by HF process before growth. A technology and mechanism of ultrafine InAs nanowire arrays grown by this method was developed, and the smallest diameter of nanowire in array has reached only 25 nm.

先进硅基芯片的特征尺寸已接近其物理极限，单纯追求器件尺寸微型化以提高集成密度的技术路线很难延续摩尔定律。以 InAs 材料为代表的 III-V 纳米线器件具有远高于硅基器件的迁移率，但它们尚未成功应用于 CMOS 纳米线器件，也未显示出卓越的性能。原因在于 III-V 材料的空穴迁移率远远低于其电子迁移率。如果纳米线直径变得超细，量子约束效应就会变得更加突出，轻空穴带将反向高于重空穴带，空穴迁移率将大大提高。为了在硅上实现 III-V 族高迁移率 CMOS 器件的可集成性，本文研究了如何在硅/二氧化硅图案化衬底上制备超细 InAs 纳米线阵列。这项工作中的新方法解决了纳米孔在生长前因高频工艺蚀刻纳米孔侧壁而导致纳米孔增大的问题。利用这种方法生长的超细 InAs 纳米线阵列的技术和机理已经开发出来，阵列中纳米线的最小直径仅为 25 nm。

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引用次数: 0

Molecular dynamics study on the mechanical behavior and deformation mechanism of gradient oxygen content nano-polycrystalline α-T 梯度氧含量纳米多晶α-T力学行为和变形机理的分子动力学研究

IF 3.8 2区材料科学 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Vacuum

Pub Date : 2024-11-13 DOI: 10.1016/j.vacuum.2024.113830

Junqiang Ren , Xinyue Zhang , Qing Gao , Qi Wang , Junchen Li , Hongtao Xue , Xuefeng Lu , Fuling Tang

Interstitial oxygen significantly affects the mechanical properties of α-Titanium (α-Ti) by modifying dislocation slip and deformation twinning mechanisms. This study utilizes molecular dynamics simulations to investigate the influence of interstitial oxygen atoms on the tensile mechanical properties and deformation mechanisms of nano polycrystalline α-Ti, taking into account two distinct average grain sizes and varying gradients of oxygen content. The pinning effect of interstitial oxygen atoms on grain boundary relaxation dislocations is critical for stabilizing the nano-polycrystalline grain boundaries (GBs), with this effect becoming increasingly pronounced as the oxygen content rises. Additionally, the simulation results indicate that oxygen atoms at the twin boundary enhance the stability of the {10

\overline{1}

2} twin boundary while exerting minimal influence on the migration of the {10

\overline{1}

1} twin boundary. The deformation associated with {10

\overline{1}

1} twinning leads to a crystallographic orientation transformation of the entire grain, which contrasts with the conventional grain rotation mechanism typically observed in nanocrystals. During plastic deformation, the primary dislocation slip mechanism is identified as the Shockley partial dislocation

\frac{1}{3}

<

\overline{1}

100>, whereas the basal plane perfect dislocation

\frac{1}{3}

<11

\overline{2}

0> easily dissociates into two Shockley partial dislocations due to the pinning effect of oxygen atoms. As a result, the dislocation density of the Shockley partial dislocation

\frac{1}{3}

<

\overline{1}

100> is the highest.

间隙氧通过改变位错滑移和变形孪生机制，对α-钛（α-Ti）的机械性能产生了重大影响。本研究利用分子动力学模拟研究了间隙氧原子对纳米多晶α-钛的拉伸机械性能和变形机制的影响，同时考虑了两种不同的平均晶粒尺寸和不同的氧含量梯度。间隙氧原子对晶界弛豫位错的钉扎效应对于稳定纳米多晶晶界（GBs）至关重要，随着氧含量的增加，这种效应越来越明显。此外，模拟结果表明，孪晶边界上的氧原子增强了{10 1‾ 2}孪晶边界的稳定性，同时对{101‾ 1}孪晶边界的迁移影响极小。与{101‾1}孪晶相关的形变会导致整个晶粒的晶体学取向转变，这与纳米晶体中通常观察到的传统晶粒旋转机制截然不同。在塑性变形过程中，主要的位错滑移机制被确定为肖克利部分位错 13 <1‾100>，而基底面完美位错 13 <112‾0>由于氧原子的钉扎效应，很容易解离成两个肖克利部分位错。因此，肖克利部分位错 13 <1‾ 100> 的位错密度最高。

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引用次数: 0

Design a self-reinforcement buffer layer to assist braze SiC and Nb with Cu-xTiH2 filler alloy 设计一种自强化缓冲层，以辅助碳化硅和铌与铜-xTiH2 填充合金的钎焊

IF 3.8 2区材料科学 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Vacuum

Pub Date : 2024-11-12 DOI: 10.1016/j.vacuum.2024.113829

Qiang Ma , Zhekai Zhu , Peng He , Yongwei Chen , Shujin Chen , Jun Wang

A buffer layer was designed to assist to braze SiC and Nb. The effect of brazing temperature and holding time on the microstructure and the shear strength of the joint was analyzed. The strengthening mechanism of the joint was evaluated. The results found that the SiC-Nb joint was brazed with Cu-5TiH₂, because of its good wettability on the surface of SiC. The typical microstructure of SiC-Nb joint brazed at 1060 °C for 5 min was SiC/C particles + TiC + Cu(s,s)/α-Ti + Nb(s,s)/Cu(s,s)+(Ti,Nb)₅Si₃+Ti₅Si₃/α-Ti/(Ti,Nb)Si/Nb. In addition, a buffer layer formed, which was consisted of two parts: reaction layer (α-Ti + Nb(s,s)) and infiltration layer (much C particles, little TiC and Cu(s,s)). With brazing temperature and holding time increasing, element Nb continuously diffused into brazing seam and solidified into α-Ti. With Nb content increasing, the α-Ti existed in the form of discontinuous to continuous layer, and then to particles. When Nb solidified into α-Ti continuous layer, the strength of the layer was improved and effective joining between SiC and Nb formed. In addition, the buffer layer was contributed to forming a good gradient transition of coefficient of thermal expansion (CTE), and released residual stress. So, the shear strength of the joint was increased to 52.6 MPa.

设计了一个缓冲层来辅助钎焊碳化硅和铌。分析了钎焊温度和保温时间对接头微观结构和剪切强度的影响。对接头的强化机制进行了评估。结果发现，SiC-Nb 接头采用 Cu-5TiH2 进行钎焊，因为 Cu-5TiH2 在 SiC 表面具有良好的润湿性。在 1060 °C 下钎焊 5 分钟的 SiC-Nb 接头的典型微观结构为 SiC/C 颗粒 + TiC + Cu(s,s)/α-Ti + Nb(s,s)/Cu(s,s)+(Ti,Nb)5Si3+Ti5Si3/α-Ti/(Ti,Nb)Si/Nb 。此外，还形成了缓冲层，缓冲层由两部分组成：反应层（α-Ti + Nb(s,s)）和浸润层（大量 C 粒子，少量 TiC 和 Cu(s,s)）。随着钎焊温度和保温时间的增加，Nb 元素不断扩散到钎缝中，并凝固成 α-Ti。随着铌含量的增加，α-钛以不连续层到连续层，再到颗粒的形式存在。当铌凝固成α-钛连续层时，α-钛连续层的强度得到提高，SiC 和铌之间形成了有效的连接。此外，缓冲层还有助于形成良好的热膨胀系数（CTE）梯度转变，并释放残余应力。因此，接头的剪切强度提高到了 52.6 兆帕。

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引用次数: 0

Thermodynamic modelling of a twin-stage claw vacuum pump and its gas pressurization analysis 双级爪式真空泵的热力学模型及其气体增压分析

IF 3.8 2区材料科学 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Vacuum

Pub Date : 2024-11-12 DOI: 10.1016/j.vacuum.2024.113821

Yuanjie Xin , Chunji Ren , Jun Wang , Shiyang Pan , Tao Nie , Zengli Wang , Dong Cui

Multi-stage claw vacuum pumps are crucial in various industrial applications for efficiently achieving high vacuum levels compared to other positive displacement vacuum pumps. In order to elucidate the gas pressurization process of the multi-stage claw vacuum pump and clarify its structural design principles, the authors investigated a twin-stage claw vacuum pump as the main research subject, and analyzed its working characteristic. A thermodynamic model of the twin-stage claw vacuum pump describing the pressurization process was established, and the results were verified by means of experiments. Moreover, effects of the phase difference φ_Ⅰ-Ⅱ, the first-stage discharge port angle θ_d,Ⅰ and the thickness ratio B₁:B₂ on pump performance were discussed. Results show that as φ_Ⅰ-Ⅱ increases, the pump power of the first stage gradually increases, while the power of the second stage decreases and then increases. With the increase of θ_d,Ⅰ, the pump power decreases and then increases. When the suction pressure is 10 kPa, the specific power reaches its minimum value under B₁: B₂ = 2:1. As the suction pressure increases, the pump power gradually increases, and its specific power fells substantially and then levels out. These contents are of great significance for the design and optimization of multi-stage claw vacuum pumps.

与其他容积式真空泵相比，多级爪式真空泵能有效地实现高真空度，因此在各种工业应用中起着至关重要的作用。为了阐明多级爪式真空泵的气体增压过程，明确其结构设计原理，作者以双级爪式真空泵为主要研究对象，分析了其工作特性。建立了描述增压过程的双级爪式真空泵热力学模型，并通过实验对结果进行了验证。此外，还讨论了相位差φⅠ-Ⅱ、第一级出气口角度θd,Ⅰ和厚度比 B1:B2 对泵性能的影响。结果表明，随着φⅠ-Ⅱ的增大，第一级泵的功率逐渐增大，而第二级泵的功率先减小后增大。随着θd,Ⅰ的增大，泵功率先减小后增大。当吸入压力为 10 kPa 时，比功率在 B1: B2 = 2:1 条件下达到最小值。随着吸入压力的增大，泵的功率逐渐增大，比功率大幅下降，然后趋于平稳。这些内容对多级爪式真空泵的设计和优化具有重要意义。

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引用次数: 0

Preparation of Au@AuAg yolk-shell nanoparticles with porous surface and their catalytic reduction of 4-nitrophenol 具有多孔表面的 Au@AuAg 卵黄壳纳米粒子的制备及其对 4-硝基苯酚的催化还原作用

IF 3.8 2区材料科学 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Vacuum

Pub Date : 2024-11-12 DOI: 10.1016/j.vacuum.2024.113828

Meng Yao, Sitong Zhao, Xiankui Lv, Junqi Tang

Yolk-shell structure nanoparticles, consisting of outer shell, inner core and cavity, are a combination of core-shell structure and hollow structure. Due to the existence of their internal gaps, yolk-shell nanostructures have more excellent optoelectronic properties than hollow nanostructures and core-shell nanostructures, and have promising applications in catalysis, energy storage, drug delivery, lithium batteries, biosensors and nanoreactors. In this paper, gold-silver bimetallic yolk-shell nanoparticles (Au@AuAg Y-SNPs) with porous surface structure were synthesized. The morphology and structure of Au@AuAg Y-SNPs were characterized by UV–vis, XRD, SEM, TEM, HRTEM, SAED, and HAADF-STEM, the results demonstrated that the nanostructures are composed of gold and silver bimetals with various shell thickness, and tunable internal voids. In addition, the catalytic activity of the Au@AuAg yolk-shell nanoparticles were investigated based on the model catalytic reaction of hydrogenation reduction of 4-nitrophenol (4-NP) to 4-aminophenol (4-AP) with superfluous sodium borohydride. The yolk-shell nanostructure had the best catalytic activity when the ratio of Ag to Au was 1:4. The kinetic constant of the reaction, apparent rate constants (K_app) was 0.0072 s⁻¹ when 100 μL of this nanocatalyst was added. This suggests that Au@AuAg Y-SNPs have a promising application in the removal of pollutants from water bodies and environmental remediation.

卵壳结构纳米粒子由外壳、内核和空腔组成，是核壳结构和空心结构的结合体。由于其内部间隙的存在，卵黄壳纳米结构比空心纳米结构和核壳纳米结构具有更优异的光电性能，在催化、储能、药物输送、锂电池、生物传感器和纳米反应器等领域具有广阔的应用前景。本文合成了具有多孔表面结构的金银双金属卵壳纳米颗粒（Au@AuAg Y-SNPs）。通过紫外可见光、X射线衍射、扫描电镜、电子显微镜、HRTEM、SAED和HAADF-STEM对Au@AuAg Y-SNPs的形貌和结构进行了表征，结果表明该纳米结构由金银双金属组成，具有不同的壳厚度和可调的内部空隙。此外，还以过量硼氢化钠将 4-硝基苯酚（4-NP）加氢还原为 4-氨基苯酚（4-AP）的模型催化反应为基础，研究了 Au@AuAg 卵黄壳纳米粒子的催化活性。当银与金的比例为 1:4 时，蛋黄壳纳米结构的催化活性最好。当加入 100 μL 该纳米催化剂时，反应的动力学常数（表观速率常数 (Kapp) ）为 0.0072 s-1。这表明 Au@AuAg Y-SNPs 在去除水体污染物和环境修复方面具有广阔的应用前景。

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引用次数: 0

Defect engineering of anchored on F-doped BNNR surface to enhance low-frequency microwave absorption and achieve exceptional thermal conductivity properties 锚定在掺杂 F 的 BNNR 表面的缺陷工程，可增强低频微波吸收并实现优异的导热性能

IF 3.8 2区材料科学 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Vacuum

Pub Date : 2024-11-10 DOI: 10.1016/j.vacuum.2024.113826

Zhen Lv , Zhongyang Duan , Ning Jiang , Ruoxuan Zheng , Di Yin , Yufeng Bai , Tingting Yang , Tai Peng

The growing demand for AI and smart computing drives the development of compact, lightweight electronic products to mitigate electromagnetic wave (EMW) pollution and thermal management issues. This necessitates materials with enhanced microwave absorption (MA) and optimal thermal conductivity (TC). Herein, we designed and synthesized fluorinated boron nitride nanorods (F-BNNRs) in a single step via plasma ball milling. Ammonium fluoride (NH₄F) served as the fluorinating agent for hexagonal boron nitride nanorods (h-BNNRs). F-BNNR3, with a NH₄F to h-BNNR ratio of 10:1 and 5.84 % fluorine (F) content, exhibits excellent MA, achieving a minimum reflection loss (RLmin) of −68.56 dB at 5.14 GHz with a thickness of 4.32 mm. It also displays a broad MA frequency range (4.6–6.1 GHz, 15.4–17.2 GHz) with significant RL < −10 dB. Additionally, a 0.09 wt% F-BNNR3 solution achieves a thermal conductivity (TC) of 0.95 W m⁻¹K⁻¹, 134 % higher than that of a 0.09 wt% h-BNNR dispersion fluid. Following a post-static treatment, F-BNNR3 attains a TC of 0.86 W m⁻¹K⁻¹, 118 % higher than that of h-BNNR. The incorporation of F into h-BNNRs significantly enhances MA and TC performance, addressing EMW pollution and thermal management challenges in advanced communication technologies utilizing nanofluids.

对人工智能和智能计算日益增长的需求推动了紧凑型轻质电子产品的发展，以减轻电磁波（EMW）污染和热管理问题。这就要求材料具有更强的微波吸收能力（MA）和最佳的热导率（TC）。在此，我们通过等离子体球磨一步法设计并合成了氟化氮化硼纳米棒（F-BNNRs）。氟化铵（NH₄F）是六方氮化硼纳米棒（h-BNNRs）的氟化剂。F-BNNR3 的 NH₄F 与 h-BNNR 的比例为 10:1，氟（F）含量为 5.84%，具有出色的 MA 性能，在 5.14 GHz 频率下，厚度为 4.32 mm 时的最小反射损耗（RLmin）为 -68.56 dB。它还显示出宽广的 MA 频率范围（4.6-6.1 GHz、15.4-17.2 GHz），RL < -10 dB。此外，0.09 wt% F-BNNR3 溶液的热导率 (TC) 达到 0.95 W m-1K-1，比 0.09 wt% h-BNNR 分散液的热导率高 134%。经过后静态处理后，F-BNNR3 的导热系数为 0.86 W m-1K-1，比 h-BNNR 高 118%。在 h-BNNR 中加入 F 可显著提高 MA 和 TC 性能，从而解决利用纳米流体的先进通信技术中的电磁波污染和热管理难题。

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引用次数: 0

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