IF 2.1 3区工程技术 Q3 PHYSICS, APPLIED

Cryogenics

Pub Date : 2026-01-09 DOI: 10.1016/j.cryogenics.2026.104280

U.Kemal Ozturk , Ali Suat Yıldız , Murat Abdioglu

This study aims to investigate the performance parameters of high-temperature superconducting (HTS) bulks and permanent magnets (PMs) as magnetic field sources in electrodynamic suspension (EDS) systems, with the goal of enhancing the currently low magnetic lift force and reducing the high drag force in such systems. A numerical analysis is conducted on an EDS system utilizing Halbach arrays of HTS and PM bulks. The H-formulation within the Partial Differential Equation (PDE) module is employed to simulate the flux-trapping performance of the HTS bulks, with results verified by experimental data from the literature. The lift and drag forces between the arrays and an aluminium rail are investigated using the Rotating Machinery-Magnetic module of COMSOL. It is observed that increasing the width of the central sample in the array results in a higher peak value of the vertical magnetic flux density and a broader peak profile, indicating a more extended effective magnetic field region across the rail surface. The HTS-based system exhibits significantly higher lift force and loading capacity compared to its PM-based counterpart. Specifically, a Halbach array composed of three HTS bulks (10 mm, 70 mm, 10 mm widths; HTS#10-70-10) achieves a better lift force representing a 211.5 % increase over the PM array. Furthermore, the lift-to-drag ratio (LDR) of the HTS array improves by 17.2 %. The results indicate that the HTS arrays offer superior performance in terms of both lift force and energy efficiency, highlighting their potential for enhancing the applicability of HTS-EDS systems in real-scale applications. This study features the advantages of HTS-based systems in achieving higher loading capacities and more efficient operation conditions compared to the PM arrays.

本研究旨在研究高温超导体（HTS）和永磁体（pm）在电动悬架（EDS）系统中作为磁场源的性能参数，以提高目前该系统中低磁升力和降低高阻力。对利用HTS和PM体的Halbach阵列的EDS系统进行了数值分析。利用偏微分方程（PDE）模块中的h -公式模拟了HTS体的通量捕获性能，并通过文献中的实验数据验证了结果。利用COMSOL公司的旋转机械-磁力模块研究了阵列与铝导轨之间的升力和阻力。可以观察到，增加阵列中中心样品的宽度导致垂直磁通密度的峰值更高，峰值轮廓更宽，表明有效磁场区域在轨道表面上的扩展更大。与基于pm的系统相比，基于hts的系统具有更高的升力和负载能力。具体来说，由三个HTS块（10毫米、70毫米、10毫米宽度；HTS#10-70-10）组成的Halbach阵列获得了更好的升力，比PM阵列增加了21.5%。此外，HTS阵列升阻比（LDR）提高了17.2%。结果表明，HTS阵列在升力和能源效率方面都具有优异的性能，突出了其在实际应用中增强HTS- eds系统适用性的潜力。与PM阵列相比，基于hts的系统在实现更高的负载能力和更有效的运行条件方面具有优势。

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引用次数: 0

Experimental measurement of VL(L)E for R14+R32 binary mixture and theoretical assessment of cryogenic refrigeration performance R14+R32二元混合物VL(L)E的实验测量及低温制冷性能的理论评价

IF 2.1 3区工程技术 Q3 PHYSICS, APPLIED

Cryogenics

Pub Date : 2026-01-07 DOI: 10.1016/j.cryogenics.2026.104277

Yunxiao Wang , Yuqing Zhao , Shaohua Lv , Yanxing Zhao , Xueqiang Dong , Maoqiong Gong

Mixed refrigerant throttle refrigeration holds significant application potential in space, such as for Martian carbon dioxide freeze-trapping and cryogenic freezers on space stations. These scenarios impose stringent requirements on temperature control precision and temperature uniformity. Mixed refrigerants exhibiting vapor-liquid-liquid equilibrium have fewer degrees of freedom, enabling more precise control over refrigeration temperatures. Furthermore, their phase change process closely approximates isothermal evaporation, resulting in a more uniform temperature distribution. Tetrafluoromethane (R14)+difluoromethane (R32), a nonpolar-polar mixture, is a promising VLLE working fluid, but its practical utilization is limited by scarce experimental phase equilibrium data. In this study, the vapor–liquid (liquid) equilibrium characteristics of the R14+R32 binary mixture were experimentally investigated at 173.150–213.150 K. The experimental data were fitted and the binary interaction parameters were regressed using two thermodynamic models: the Peng-Robinson equation of state combined with the van der Waals mixing rule (PR-vdW), and the PR equation of state combined with the modified Huron-Vidal second-order mixing rule and the nonrandom two-liquid activity coefficient model (PR-MHV2-NRTL). For the PR-vdW model, the maximum average absolute relative deviation of pressure (AARDp) and average absolute deviation of vapor-phase composition (AADy) were 3.03% and 0.0092, respectively. For the PR-MHV2-NRTL model, the corresponding values were 1.65% and 0.0103. Further investigation was conducted on the refrigeration performance of R14+R32. The results showed that the mixture achieved a maximum exergy efficiency of 44%. This highlights its potential for high-precision cryogenic systems and extraterrestrial applications, such as stratospheric and Martian environments. This work provides the first comprehensive experimental dataset and thermodynamic assessment for the R14+R32 mixture, enabling accurate design of next-generation cryogenic refrigeration systems.

混合制冷剂节流制冷在空间中具有重要的应用潜力，例如用于火星上的二氧化碳冷冻捕获和空间站上的低温冷冻机。这些场景对温度控制精度和温度均匀性提出了严格的要求。混合制冷剂表现出气-液-液平衡，具有更少的自由度，能够更精确地控制制冷温度。此外，它们的相变过程非常接近等温蒸发，从而使温度分布更加均匀。四氟甲烷(R14)+二氟甲烷（R32）作为一种非极性-极性混合物，是一种很有前途的VLLE工质，但其实际应用受到缺乏相平衡实验数据的限制。在173.150 ~ 213.150 K的温度下，实验研究了R14+R32二元混合物的气液（液）平衡特性。采用结合范德华混合规则的彭氏-罗宾逊状态方程（PR- vdw）和结合改进的休伦-维达尔二阶混合规则和非随机双液活度系数模型（PR- mhv2 - nrtl）两种热力学模型对实验数据进行拟合，并对二元相互作用参数进行回归。PR-vdW模型的最大平均绝对相对压力偏差（AARDp）和气相组成平均绝对偏差（AADy）分别为3.03%和0.0092。PR-MHV2-NRTL模型对应的值分别为1.65%和0.0103。对R14+R32的制冷性能进行了进一步的研究。结果表明，该混合料的最高火用效率为44%。这突出了它在高精度低温系统和地外应用（如平流层和火星环境）方面的潜力。这项工作为R14+R32混合物提供了第一个全面的实验数据集和热力学评估，为下一代低温制冷系统的精确设计提供了可能。

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引用次数: 0

Measurement of the thermal conductivity of high-purity aluminum and OFHC copper for the CUPID pulse tube cryocoolers thermal links 用于丘比特脉冲管制冷机热链路的高纯度铝和OFHC铜导热系数的测量

IF 2.1 3区工程技术 Q3 PHYSICS, APPLIED

Cryogenics

Pub Date : 2025-12-29 DOI: 10.1016/j.cryogenics.2025.104276

F. Agresti , A. Benato , C. Bucci , I. Calliari , A. D’Addabbo , S. D’Eramo , S. Di Lorenzo , S. Fu , P. Gorla , L. Marini , M. Olmi , L. Pezzato , M. Pigato , A. Puiu , S. Quitadamo , A. Zambon

We present a campaign of thermal conductivity measurements of Oxygen Free High Conductivity (OFHC) copper (

>

99.9% purity) and high-purity 5N and 6N aluminum. High-purity aluminum is devoted to replace the current OFHC copper thermal links of the Pulse Tube Cryocoolers (PTC) installed in the

^{3} He

-

^{4} He

dilution cryostat of the CUORE (Cryogenic Underground Observatory for Rare Events) experiment, in view of the future commissioning of the CUPID (CUORE Upgrade with Particle IDentification) experiment, both dedicated to the search of neutrinoless double beta decay. We perform thermal conductivity measurements on high-purity aluminum (

Al

-5N and

Al

-6N) and OFHC copper samples across the temperature range from 12 K to 45 K, and then extrapolate them down to 3.5 K, namely the minimum temperature achieved by the second stage of the CUORE PTC. We estimated that the thermal conductivity of high-purity aluminum at 3.5 K is up to

≃

17 times higher than that of OFHC copper. However, the measured thermal conductivity of high-purity aluminum has been found to be limited by the boundary thermal resistance ascribed to the oxidation of the aluminum surface. By quantifying and accounting for such contribution, we estimated the actual thermal conductivity of

Al

-6N to be

≃

61 times higher value than that of OFHC copper. These findings suggest that high-purity aluminum thermal links offer a promising solution to meet the stringent requirements of the successor of CUORE, the CUPID experiment, in terms of cooling power enhancement and vibration suppression.

我们提出了一项无氧高导电性（OFHC）铜（纯度>；99.9%）和高纯5N和6N铝的热导率测量运动。高纯铝专门用于取代目前安装在CUORE（低温地下罕见事件观测站）实验3He-4He稀释低温恒温器（PTC）中的脉冲管制冷机（PTC）的OFHC铜热链接，以考虑到丘比特（CUORE升级与粒子识别）实验的未来调试，这两个实验都致力于寻找中微子双β衰变。我们在12 K至45 K的温度范围内对高纯度铝（Al-5N和Al-6N）和OFHC铜样品进行导热系数测量，然后将其外推至3.5 K，即CUORE PTC第二阶段达到的最低温度。我们估计在3.5 K时，高纯度铝的导热系数比OFHC铜的导热系数高17倍。然而，高纯度铝的热导率被发现受到铝表面氧化引起的边界热阻的限制。通过量化和计算这一贡献，我们估计Al-6N的实际导热系数比OFHC铜高61倍。这些发现表明，高纯度铝热链接提供了一个有希望的解决方案，以满足CUORE的继任者丘比特实验在冷却功率增强和振动抑制方面的严格要求。

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引用次数: 0

Design and characterization of an alumina coated helium gas gap heat switch with adjustable gap width 间隙宽度可调的氧化铝包覆氦气间隙热开关的设计与表征

IF 2.1 3区工程技术 Q3 PHYSICS, APPLIED

Cryogenics

Pub Date : 2025-12-25 DOI: 10.1016/j.cryogenics.2025.104275

Kun Wang , Shuai Ma , Kuifan Zha , Liming Han , Yi Liao , Changzhao Pan

Gas gap heat switches, with the advantages of simple operation, no moving parts, and large switching ratios, are widely applied in helium evaporation refrigerator, adiabatic demagnetization refrigerator, and dilution refrigerator. In this study, a sintered alumina (Al₂O₃) coated helium gas gap heat switch (GGHS) was successfully developed, adopting a concentric copper block structure, where the gap width was precisely controlled by adjusting the thickness of the sintered alumina coating. In the constructed 4 K test system, the thermal conductance, switching temperature, and switching time of the switch were systematically tested, and the results show that when the average temperature of the switch is 30 K, the peak thermal conductance reaches 255 mW/K; at a cold end temperature of 3 K, the OFF and ON state thermal conductance are 0.27 mW/K and 35 mW/K, respectively. Further verification of the switching temperature shows that the theoretical prediction agrees well with the experimental data, confirming the reliability of the theoretical model. In addition, the switch exhibits good dynamic response characteristics, with a switching time of 70 s from OFF state to ON state, and only 17 min required for the adsorption pump to cool during the ON to OFF transition. Finally, to evaluate its practical performance, the heat switch was implemented in a custom-built dilution refrigerator, where the system successfully cooled to 10 mK within 32.5 h. The above study confirms that the sintered alumina coating helium gas gap heat switch provides reliable performance, offering an effective solution for thermal management in cryogenic systems.

气隙热开关具有操作简单、无运动部件、开关比大等优点，广泛应用于氦气蒸发制冷机、绝热退磁制冷机、稀释制冷机等。本研究成功研制了一种烧结氧化铝（Al2O3）涂层氦气间隙热开关（GGHS），采用同心铜块结构，通过调整烧结氧化铝涂层的厚度来精确控制间隙宽度。在搭建的4 K测试系统中，对开关的热导率、开关温度、开关时间进行了系统测试，结果表明：当开关的平均温度为30 K时，热导率峰值达到255 mW/K；冷端温度为3 K时，关闭和打开状态的热导率分别为0.27 mW/K和35 mW/K。对开关温度的进一步验证表明，理论预测与实验数据吻合较好，证实了理论模型的可靠性。此外，该开关具有良好的动态响应特性，从OFF状态切换到ON状态的切换时间为70 s，从ON到OFF过渡过程中吸附泵的冷却时间仅为17 min。最后，为了评估其实际性能，将热开关应用于定制的稀释冰箱中，系统在32.5 h内成功冷却到10 mK。上述研究证实了烧结氧化铝涂层氦气间隙热开关具有可靠的性能，为低温系统的热管理提供了有效的解决方案。

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引用次数: 0

A gravity independent hydrogen heat pipe 一种不依赖重力的氢热管

IF 2.1 3区工程技术 Q3 PHYSICS, APPLIED

Cryogenics

Pub Date : 2025-12-23 DOI: 10.1016/j.cryogenics.2025.104270

Ziyang Hang, John Pfotenhauer, Franklin Miller

A new type of heat pipe called Hybrid Conventional Pulsating Heat Pipe (HCPHP), which works similarly to a conventional heat pipe but retains the advantageous geometry of a pulsating heat pipe, is experimentally verified within the saturated hydrogen temperature range and under horizontal working orientation. The Hydrogen HCPHP shows up to 1.625 W of heat transfer with thermal conductance up to 6.15 W/K and effective thermal conductivity up to 54,621 W/m-K over a 250 mm heat transfer distance. Experimental investigations of the hydrogen HCPHP focus on the condenser temperature, fluid fill ratio, and applied heat load. Thermohydraulic behavior of the Hydrogen HCPHP is analyzed, providing insights into its performance and behavior.

混合常规脉动热管（HCPHP）是一种新型热管，它的工作原理与传统热管相似，但保留了脉动热管的优势几何形状，在饱和氢温度范围内和水平工作方向下进行了实验验证。在250mm的传热距离上，HCPHP的换热量为1.625 W，导热系数为6.15 W/K，有效导热系数为54,621 W/m-K。实验研究主要集中在凝汽器温度、充液比和外加热负荷方面。分析了氢气HCPHP的热液行为，为其性能和行为提供了见解。

引用次数: 0

Investigation of the effect of electrode configuration on sensitivity and linearity of capacitance-based void fraction sensors for cryogenic nitrogen two-phase flow 电极结构对电容式低温氮两相流空分数传感器灵敏度和线性度影响的研究

IF 2.1 3区工程技术 Q3 PHYSICS, APPLIED

Cryogenics

Pub Date : 2025-12-20 DOI: 10.1016/j.cryogenics.2025.104268

Tony John , Rijo Jacob Thomas , K.A. Shafi

Capacitance-based sensors, which are favored for the measurement of void fraction in two-phase cryogenic flow, suffer from low sensitivity and linearity due to the low relative permittivity of cryogens and the non-uniform electric field inside the flow area, respectively. This paper compares the sensitivity and linearity of concave, parallel plate and concentric electrodes for use in capacitance-based void fraction sensors. The simulation model was validated using a concave electrode sensor with stratified flow. The simulation results show that of the three electrode shapes considered, concentric electrodes exhibit excellent sensitivity for both stratified and annular flow regimes and good linearity for stratified flow. Even though they have low sensitivity, the parallel plate electrodes give the best linear behavior between void fraction and capacitance for both flow regimes.

由于低温介质的相对介电常数较低，流动区域内电场不均匀，电容式传感器的灵敏度较低，线性度较低，是两相低温流动中空隙率测量的理想传感器。本文比较了凹电极、平行电极和同心电极在电容式空隙率传感器中的灵敏度和线性度。采用分层流凹电极传感器对仿真模型进行了验证。仿真结果表明，在考虑的三种电极形状中，同心电极对分层流和环形流都具有良好的灵敏度，对分层流具有良好的线性性。尽管它们的灵敏度较低，但平行板电极在两种流动模式下的空隙率和电容之间具有最佳的线性行为。

引用次数: 0

β’-Gd2(MoO4)3: A promising candidate in the sub-Kelvin temperature region β′-Gd2(MoO4)3：亚开尔文温度区域的一个有希望的候选者

IF 2.1 3区工程技术 Q3 PHYSICS, APPLIED

Cryogenics

Pub Date : 2025-12-19 DOI: 10.1016/j.cryogenics.2025.104269

Zuhua Chen , Jiahao Gao , Xinqi Zheng , Guochun Zhang , Lei Xi , Zhenxing Li , Shilin Yu , Heng Tu , Jun Shen , Shouguo Wang

Magnetic refrigeration technology is one of the important technologies to realize sub-Kelvin temperature environment, in which magnetocaloric materials are of great importance. Polycrystalline powder of β’-Gd₂(MoO₄)₃ was prepared by solid-phase synthesis, and the structure as well as magnetic properties were further investigated. The thermomagnetic curves show that the magnetic ordering temperature is about 0.6 K for β’-Gd₂(MoO₄)₃. The maximum magnetic entropy change of β’-Gd₂(MoO₄)₃ was calculated to be 20.7 and 34.1J kg⁻¹·K⁻¹ under the magnetic field changes from 0 to 1 T and 2 T, respectively. Moreover, the magnetic entropy change curves of β’-Gd₂(MoO₄)₃ at low field have obvious platform-like characteristic, which allows it to act as a refrigerant for wide refrigeration temperature range, thereby improving the overall heat transfer efficiency of the system. These properties make β’-Gd₂(MoO₄)₃ a powerful candidate of magnetic refrigeration materials in the sub-Kelvin temperature cooling.

磁致冷技术是实现亚开尔文温度环境的重要技术之一，其中磁致热材料具有重要意义。采用固相法制备了β′-Gd2(MoO4)3多晶粉体，并对其结构和磁性能进行了进一步研究。热磁曲线表明，β′-Gd2(MoO4)3的磁有序温度约为0.6 K。计算得到β′-Gd2(MoO4)3在0 ~ 1 T和2 T磁场变化下的最大磁熵变化分别为20.7和34.1J kg−1·K−1。此外，β′-Gd2(MoO4)3在低场下的磁熵变化曲线具有明显的平台型特征，可以在较宽的制冷温度范围内作为制冷剂，从而提高了系统的整体换热效率。这些特性使β′-Gd2(MoO4)3成为亚开尔文温度冷却磁致冷材料的有力候选材料。

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引用次数: 0

Low-temperature sintering of ex situ processed MgB2 tapes under various hydrogen partial pressures 不同氢分压下非原位加工MgB2带的低温烧结

IF 2.1 3区工程技术 Q3 PHYSICS, APPLIED

Cryogenics

Pub Date : 2025-12-17 DOI: 10.1016/j.cryogenics.2025.104259

Hiroki Fujii

Ex situ processed Fe-sheathed tapes using a mixture of MgB₂ and Sn powders milled for 30 and 100 h were sintered at 410 – 710 ℃ under hydrogen partial pressures of 0, 5, 20, 50 and 100 kPa in a gas mixture of Ar and H₂. The filling powders were pure MgB₂ and the mixture with the addition of 3.7 wt% Sn. Without addition of Sn, tapes sintered under a pure H₂ atmosphere show well-connected structure of grains in the core or improved grain connectivity in microstructure compared to tapes sintered under a pure Ar atmosphere. The undoped tapes sintered at 680 ℃ under pure Ar or 530 ℃ under pure H₂ exhibit transport critical current density (J_c) values of approximately 150 A/mm² at 4.2 K and 10 T. Therefore, sintering under pure H₂ is effective in reducing the sintering temperature. The sintering temperature of 530 ℃ is lower than the melting point of lightweight Al, which is one of the candidates for sheath materials for MgB₂ conductors, which is 660 ℃. Regarding the control of hydrogen partial pressure, the critical temperature (T_c) of the tapes increases by up to 2 K as the hydrogen partial pressure increases. However, the transport J_c values at 4.2 K and 10 T of these tapes sintered in a flow of mixed gas of Ar and H₂ do not improve compared to those sintered under pure H₂. Thus, sintering under pure H₂ is the most effective in the improvement in T_c and transport J_c. Whereas Sn addition is effective in shifting the transport J_c versus sintering temperature curves to a lower sintering temperature under pure Ar, the addition brings about neither such a shift nor transport J_c enhancement under pure H₂. These results lead to the fabrication of lightweight Al-sheathed conductors for applications such as maglev trains.

采用MgB2和Sn混合粉末，在Ar和H2混合气体中，在410 ~ 710℃下，在0、5、20、50和100 kPa的氢分压条件下，进行非原位加工铁包覆带的烧结。填充粉末为纯MgB2和添加3.7 wt% Sn的混合物。与纯Ar气氛下烧结的带相比，未添加Sn的纯H2气氛下烧结的带芯晶粒连接良好，微观结构上晶粒连通性提高。在纯Ar和纯H2下分别在680℃和530℃下烧结的未掺杂带在4.2 K和10 t下的输运临界电流密度（Jc）约为150 A/mm2，因此，纯H2下烧结能有效降低烧结温度。烧结温度为530℃，低于轻质铝的熔点660℃，是MgB2导体护套材料的候选材料之一。在氢气分压的控制方面，随着氢气分压的增加，胶带的临界温度（Tc）提高了2 K。然而，在Ar和H2混合气体中烧结的带在4.2 K和10 T时的输运Jc值与纯H2下烧结的带相比没有提高。因此，纯H2烧结对提高Tc和输运Jc最为有效。在纯Ar条件下，Sn的加入可以有效地将输运Jc随烧结温度曲线移动到较低的烧结温度，而在纯H2条件下，Sn的加入既没有引起这种移动，也没有增强输运Jc。这些结果导致了用于磁浮列车等应用的轻质铝护套导体的制造。

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引用次数: 0

Magnetic properties and low-temperature magnetocaloric performances in fluorite-type Tb2Zr2O7 compound 萤石型Tb2Zr2O7化合物的磁性能和低温磁热性能

IF 2.1 3区工程技术 Q3 PHYSICS, APPLIED

Cryogenics

Pub Date : 2025-12-16 DOI: 10.1016/j.cryogenics.2025.104266

Jiameng Xu, Fuyu Yang, Yikun Zhang, Xinyu Zhao, Zhe Kong

The low-temperature magnetocaloric (MC) performances in rare-earth (RE)-based magnetic materials have been determined intensively which are aimed to explore suitable materials for magnetic refrigeration (MR) application. In this work, we synthesized the Tb₂Zr₂O₇ compound using solid-state reaction method and characterized its crystal structure, elemental valence states, magnetism, and low-temperature MC properties. The Tb₂Zr₂O₇ compound crystallizes in a fluorite-type cubic structure and orders magnetically around the temperature of 2.2 K. The consistent elements are all distributed uniformly and presented as Tb³⁺, Zr⁴⁺, and O^2– valence states, respectively. Prominent low-temperature MC performances have been realized in Tb₂Zr₂O₇ compound which were related to its second order type magnetic phase transition. The MC parameters of maximum magnetic entropy change and refrigerant capacity for Tb₂Zr₂O₇ compound under magnetic field variation of 0–7 T reach 11.8 J/kg·K and 192.2 J/kg, respectively. These MC parameters are comparable with some recently reported RE-based high-performing MC materials, making the Tb₂Zr₂O₇ compound may also considerable for low-temperature MR applications.

对稀土基磁性材料的低温磁热性能进行了深入的研究，旨在探索适合磁制冷应用的材料。本文采用固相反应方法合成了Tb2Zr2O7化合物，并对其晶体结构、元素价态、磁性和低温MC性能进行了表征。Tb2Zr2O7化合物结晶为萤石型立方结构，在2.2 K左右有磁性有序。一致元素分布均匀，分别表现为Tb3+、Zr4+和O2 -价态。Tb2Zr2O7化合物具有优异的低温MC性能，这与其二级磁相变有关。在0 ~ 7 T的磁场变化下，Tb2Zr2O7化合物的最大磁熵变化和制冷剂容量MC参数分别达到11.8 J/kg·K和192.2 J/kg。这些MC参数与最近报道的一些基于re的高性能MC材料相当，使得Tb2Zr2O7化合物也可以用于低温MR应用。

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引用次数: 0

Effects of connection conditions on lap joint performance in REBCO CORC cables 连接条件对REBCO CORC电缆搭接性能的影响

IF 2.1 3区工程技术 Q3 PHYSICS, APPLIED

Cryogenics

Pub Date : 2025-12-16 DOI: 10.1016/j.cryogenics.2025.104265

Chuanyi Zhao , Huan Jin , Guanyu Xiao , Le Wang , Peng Gao , Chao Zhou , Jinggang Qin

The REBCO conductor on round core (CORC) cable, featuring high mechanical strength and high current density, has emerged as the preferred option for high-field superconducting magnets. Considering economic and safety factors, the large-scale nested superconducting magnets wound from these cables are designed to adopt demountable lap joints to realize electrical connections between sub-coils. This study focuses on comparing lap joints based on the REBCO CORC cable prepared from different materials, and testing their performance at 77 K and self-field. The results indicate that the deformable fine indium wires used as the inserts results in the lowest resistance of the REBCO CORC lap joints. Moreover, the resistivity of the connecting material is not the only factor affecting the performance of the lap joints, the material adhesion effect on the joint surface and the thickness of the material are also related to the performance of the lap joints. The conclusions are informative for the development of large aperture nested REBCO CORC magnets.

圆芯（CORC）电缆上的REBCO导体具有高机械强度和高电流密度的特点，已成为高场超导磁体的首选。考虑到经济和安全因素，将这些电缆缠绕成的大型嵌套超导磁体设计为采用可拆卸搭接方式，实现子线圈之间的电气连接。本研究的重点是比较不同材料制备的REBCO CORC电缆搭接接头，并测试其在77 K和自场下的性能。结果表明：采用可变形细铟丝作为衬垫，可使REBCO - CORC搭接接头的电阻最低；此外，连接材料的电阻率并不是影响搭接接头性能的唯一因素，材料在接头表面的附着效果和材料的厚度也与搭接接头的性能有关。所得结论为大孔径嵌套REBCO CORC磁体的研制提供了参考。

引用次数: 0

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