CERAMICS INTERNATIONAL
·
2024
·
IF 5.1
Chen Zhang,Benzheng Gao,Houyang Yu,Xin Wang,Jianliang Xie
CaO–B 2 O 3 –SiO 2 (CBS) is a promising lightweight, low-dielectric matrix material for high-temperature microwave-absorbing coatings. However, the comprehensive study of absorbent morphology evolution within such coatings and its influence on electromagnetic (EM) performance has not been conducted. In this work, a series of FeSiAl (FSA)/CBS composite coatings with various FSA contents were fabricated using atmospheric plasma spraying. The morphological evolution of the FSA phase and the resulting EM properties of the coatings were systematically analyzed. Experimental findings show that during the spraying process, when the size of FSA clusters in the composite powder exceeds the thickness of CBS splats, FSA clusters form a rigid contact with the underlying solidified coating, leading to the development of a lamellar structure. This lamellar FSA phase creates local conductive networks, which significantly increase the complex permittivity of the coating. These results provide valuable guidance for controlling absorbent morphology and optimizing the EM properties of CBS-based coatings.
研究领域:
材料科学
·
电磁学
✓ 已验证
产品关联
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2023
·
IF 6.7
Qihui Sun,Jinyao Li,Hongyan Zhang,Xiong He,Baoshan Wu,Junwei Wang,Nasir Mahmood,Xian Jian
Traditional single-component microwave absorbers face the difficulties including the narrow absorption bandwidth and low absorption strength. Herein, we develop a novel dual-magnetic composite decorating with covalent-organic framework (COF of 1,3,5-triformylphloroglucinol and p-phenylenediamine: TpPa) and carbon hybrid to enhance microwave absorption performance. Namely, a dual-magnetic FeSiAl@(CoFe 2 O 4 /C)@TpPa core–shell structure with rich interfacial polarizations was prepared by the three main steps: firstly, the plate-like FeSiAl was decorated with the MOFs of ZIF-67. And then it was converted to FeSiAl@(CoFe 2 O 4 /C) after an annealing process under Ar. Lastly, the in-situ growth of COF (TpPa) was designed for enhanced microwave penetration into the interior of absorbers. The as-design dual-magnetic FeSiAl/CoFe 2 O 4 effectively favors to magnetic domain resonance resulting in the dual-magnetic coupling effects. Meanwhile, the multi-level structure formed by ultra-fine carbon in FeSiAl@(CoFe 2 O 4 /C)@TpPa enables magnetic-dielectric synergies and enriches the attenuation path as well. Furthermore, the accumulation of transferred charge at multiple interfaces provides a stronger relaxation polarization loss. The above positive factors collectively promote the high-performance microwave absorption with the reflection loss (RL) value up to −51.3 dB and the effective absorption bandwidth (EAB) covers 3.2–17.7 GHz by adjusting the thickness of absorbers. Therefore, this dual-magnetic/dielectric coupling approach provides an innovative strategy for fabricating advanced microwave absorbers.
研究领域:
材料科学
·
电磁学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE
·
2023
·Vol. 58
·期 23
·9698-9707
·
IF 4.5
Zhang Cong,Chen Yanan,Feng Shuangjiu,Kan Xucai,Zhu Yong,Li Yue,Sun Wei,Shen Jibiao,Liu Xiansong
Currently, soft magnetic composites (SMCs) are usually used for high-current power devices. As a kind of SMCs, the FeSiAl magnetic powder core exhibits excellent magnetic properties, but it is difficult to improve its permeability and DC-bias characteristics. Thus, developing SMC s with high permeability and lower power loss remains a challenge. Here, the FeSiAl powder was mixed with carbonyl iron powder (CIP) which coated with nano-SiO 2 and pressed into toroidal magnetic core with silicon resin as adhesive. For MHz frequency, the SMCs with excellent power loss, saturation magnetization and permeability were obtained. Saturation magnetization of the mixed powder increased markedly with the CIP content increasing. For magnetic powder cores, the SEM and the mappings show that the large deformation CIP was helpful to improve core density. With the addition of CIP, the permeability and DC-bias properties were improved. In addition, the power loss was greatly reduced by the optimized annealing temperature.
研究领域:
材料科学
·
电磁学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS
·
2023
·
IF 2.7
Meng Jin,Fan Zhao,Ming Liu
As a hotspot of soft magnetic composites (SMCs), the magnetic properties and loss characteristics of FeSiAl SMCs at high frequency need to be further optimized. In this study, the FeSiAl with flaky morphology was obtained by mechanical ball milling to improve its permeability, the reduction of power loss and the optimization of magnetic properties were achieved by the Ni 0.4 Zn 0.6 Fe 2 O 4 cladding layer. For comparison, phosphoric acid-passivated flaky FeSiAl was prepared. The results indicated that due to the good coating effect and high resistivity of NiZn ferrite, the Ni 0.4 Zn 0.6 Fe 2 O 4 coated flaky FeSiAl has a high permeability ( μ e ≈ 100) with extraordinary frequency stability in the range of 100 kHz–10 MHz, a higher quality factor with the peak occurs in higher frequency bands (Q = 72 at around 1 MHz), and a low relative loss factor of the order of 10 −3 –10 −4 in the range of 20 kHz–8 MHz. In addition, the ferrite-coated flaky FeSiAl also has outstanding high-frequency power loss performance, which can be explained by the coercivity in the VSM results and the reduced eddy current loss obtained by loss separation. This work broadens ideas for improving high-frequency applications of FeSiAl SMCs.
研究领域:
材料科学
·
电磁学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF PHYSICS D-APPLIED PHYSICS
·
2025
·Vol. 58
·期 13
·135005
·
IF 3.2
Rongdi Guo,Jiaxiang Qin,Guohua Wu,Zhongqiang Hu,Ming Liu
Soft magnetic composites (SMCs) are considered key elements for attaining electromagnetic signal transmission and conversion. However, they require high permeability and low core losses to ensure the efficient and stable operation of electronic devices, such as inductors and sensors. To effectively address these issues, in this work, AlN nanopowders were used to coat FeSiAl spherical particles. In parallel, the effect of coating AlN nanopowders on the electromagnetic properties of FeSiAl SMCs was investigated. By performing energy dispersive spectroscopy analysis, AlN was confirmed to be attached to the FeSiAl spherical particles, indicating the existence of an excellent AlN coating quality. Although the incorporation of the AlN coating layer yielded a monotonic reduction in saturation magnetization intensity and effective permeability, it also effectively suppressed core losses. Due to the high-resistance of AlN, the high-resistance layer developed on the surface of the FeSiAl particles can substantially increase the resistivity of FeSiAl SMCs, and then the eddy current loss was suppressed. When coated with 1.5 wt% AlN, the FeSiAl SMCs exhibited the lowest core losses of 394 kW m−3 at 100 kHz, 100 mT, and room temperature. The proposed AlN-coated FeSiAl SMCs in this work exhibited a good overall performance, and are expected to be applied in high-performance inductor devices.
研究领域:
材料科学
·
电磁学
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2025
·
IF 5.6
Jiabin Fan,Jiayi Sun,Xiuyuan Fan,Chuang Liu,Qian Wang,Jianhang Zheng,Shiliang Xu,Konglei Zhu,Jiaying Jin,Guohua Bai
Soft magnetic composites (SMCs) composed of insulating magnetic particles are essential for advancements in power electronics. Nonetheless, the high molding pressure associated with traditional cold-pressing methods compromise the integrity of insulating layers, thereby limiting their applicability in high-frequency applications. This study employs a cold sintering process to fabricate FeSiAl SMCs using FeSiAl flakes and ammonium molybdate tetrahydrate (AMT). The FeSiAl flakes are effectively consolidated, and a multi-layer insulation structure of Al 2 O 3 ·SiO 2 /Fe 2 (MoO 4 ) 3 can be formed in-between FeSiAl flakes, which endows the SMC with great high-frequency performance, characterized by a permeability of 60.7, a cut-off frequency of 38.7 MHz, a saturation magnetization of 121.4 emu/g, and a power loss of 2028.5 kW/m³ (at 10 MHz, 5 mT). This work highlights a new strategy for simultaneous consolidation and insulation of metallic magnetic particles at low pressure and low temperature, which shows great potential in fabricating high-frequency SMCs.
研究领域:
材料科学
·
电子工程
✓ 已验证
产品关联
DOI
高影响因子
MATERIALS SCIENCE IN SEMICONDUCTOR PROCESSING
·
2024
·
IF 4.2
Yang Guo,Rui Zhou
Corrosion-resistant ferromagnetic absorbers (FMAs) with self-healing properties are crucial for enhancing their durability under harsh conditions. Herein, we fabricated lychee-like FeSiAl (FSA)@C@SiO 2 @1H-Benzotriazol (BTA) coupled with multiple heterogeneous interfaces by coating FSA with a C@SiO 2 @BTA layer using sol-gel, thermal reduction, and molecular encapsulation techniques. The FSA@C@SiO 2 @BTA showed superior microwave absorption (MA) performance than FSA, with a widest absorption bandwidth of 10.44 GHz at 1.98 mm and a maximum reflection loss of −57.81 dB at 2.98 mm. The enhanced MA performance was due to the better impedance matching and the synergistic effects of interfacial and dipole polarization induced by the C@SiO 2 @BTA layer. Moreover, the FSA@C@SiO 2 @BTA exhibited a remarkable corrosion resistance, with a corrosion rate of 3.28 × 10 −10 m/s, which was two orders of magnitude lower than that of FSA, and a corrosion protection efficiency of 99.0 %. The epoxy resin coating containing FSA@C@SiO 2 @BTA also demonstrated a self-healing ability within 5 min after being damaged mechanically. This study presents a novel model that integrates MA, corrosion resistance, and self-healing, heralding new avenues for developing corrosion-resistant FMAs in marine applications.
研究领域:
材料科学
·
腐蚀与防护
·
电磁学
✓ 已验证
产品关联
DOI
高影响因子
Small
·
2025
·
IF 12.1
Hui Luo,Lingxin Kong,Sihai Lv,Qifan Li,Mi Tang,Xujin Ge,Fu Chen,Yongzhi Cheng,Xiangcheng Li
The rational manipulation of interfacial properties, composition, and morphology of materials has emerged as an effective strategy for enhancing their microwave absorption performance. The crystal phase composition, microstructure, and electromagnetic properties can be regulated by varying the thermal treatment temperature. The synergistic integration of heterogeneous interfaces, magnetic materials, microstructures, and defect engineering helps optimize impedance matching and enhance polarization and magnetic losses. Herein, multi-interface core–shell FeSiAl@MnO x @C composites with various morphologies demonstrated superior microwave absorption performance. A minimum reflection loss of −56.3 dB is achieved at an absorber thickness of 1.41 mm, and effective absorption bandwidth of 5.0 GHz is obtained at a thickness of 1.59 mm. The radar cross-section reduction value reached 19.448 at an incidence angle of 0°. The excellent microwave absorption performance is due to the synergistic effect of the significant magnetic and dielectric losses and improved impedance matching. This study establishes a foundation for designing next-generation high-performance microwave-absorbing materials with high magnetic losses.
研究领域:
材料科学
·
电磁学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ADVANCED POWDER TECHNOLOGY
·
2024
·
IF 4.2
Zigui Luo,Qi Jin,Rui Wang,Zhenjia Yang,Zhaoyang Wu,Guangqiang Li,Xi’an Fan
FeSiAl/(Al 2 O 3 -Ni) soft magnetic composites (SMCs) were prepared by sintering FeSiAl/NiO composite powders, and the formation mechanism of the Al 2 O 3 -Ni composite coating and performance of the FeSiAl SMCs with different NiO coating content were studied. During sintering, high temperature promoted a reaction between Al and NiO at the FeSiAl/NiO interface, resulting in the in-situ formation of a composite coating comprising Al 2 O 3 coating with high integrity and ferromagnetic Ni coating. The interdiffusion of Al and O 2– toward the interface ensured the continuation of the reaction and growth of the composite coating. The composite coating thickened with the increasing NiO coating content, thus showing reduced real part of permeability. Saturation magnetization considerably increased until the NiO coating content exceeded 12.5 wt% owing to residual NiO. Excessive NiO coating content led to the generation of a large amount of Ni, which was not conducive to the integrity of the Al 2 O 3 coating and increased magnetic loss. The FeSiAl SMCs with 5.0 wt% NiO coating content exhibited exceptional performance with high saturation magnetization (135.3 emu/g), good frequency stability of permeability, and low magnetic loss (63.7 W/kg at 0.05 T/20 kHz).
研究领域:
材料科学
·
磁学
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2024
·
IF 5.1
Chen Zhang,Xin Wang
In this paper, CaO-B 2 O 3 -SiO 2 (CBS) is utilized as matrix material of microwave coating for the first time to achieve high-performance microwave absorption under high-temperature. A series of FeSiAl (FSA)/CBS composite coatings were prepared via atmospheric plasma spraying. The impact of spraying power on the microstructure, electromagnetic properties, and high-temperature stability of as-sprayed coatings were studied. The experimental results reveal that CBS could effectively suppress the formation of the lamellar structure of FSA as the low initial melting temperature, also form unexpected Fe 2 SiO 4 structure with FSA during the spraying process. The increase in complex permittivity of the coating is primarily attributed to enhanced coating density and the development of Fe-rich regions within the CBS matrix. Furthermore, the dense coating prevents the oxidation of FSA and exhibits high-temperature stability. Our coating of 1 mm thickness has a reflection loss below -5 dB with frequency range of 7–14.8 GHz at 500 °C.
研究领域:
材料科学
·
电磁学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2024
·
IF 5.8
Wangchang Li,Weichao Yang,Yao Ying,Jing Yu,Jingwu Zheng,Liang Qiao,Juan Li,Shenglei Che
FeSiAl soft magnetic composites (SMCs) with phosphate-silicone resin as the insulating layer were prepared by phosphating FeSiAl powder with K 3 PO 4 solution. The effects of K 3 PO 4 content on the microstructure and composition of the insulation coating were investigated. Further, the soft magnetic properties of SMCs were analyzed in detail. It is revealed that the annealed inorganic coating layer which predominantly consists of Al(PO 3 ) 3 , Al 2 O 3 , and P 2 O 5 exhibits a high resistivity, high temperature resistance and thin thickness, significantly reducing the eddy current loss. The outstanding magnetic properties of a power loss of 118.6 kW/m 3 (100 kHz, 0.1 T) and permeability of 63.8 were achieved for this high-quality thin insulation coating. Moreover, the magnetic loss was separated into hysteresis, eddy current and excess part, and the mechanism was analyzed in detail. The reduced total loss can be ascribed to the suppression of the eddy current. The novel SMCs coating with K 3 PO 4 are particularly suitable for applications in high frequency and high DC bias situations for switching power supplies, photovoltaic inverter boost inductors and other applications.
研究领域:
材料科学
·
电磁学
✓ 已验证
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2023
·
IF 6.2
Wangchang Li,Xiang Zhou,Yue Kang,Ting Zou,Wanjia Li,Yao Ying,Jing Yu,Jingwu Zheng,Liang Qiao,Juan Li,Shenglei Che
Novel FeSiAl soft magnetic composites (SMCs) with a phosphate insulation coating doped with magnetic NiFe2O4 nanocrystalline particles were prepared. They exhibited high permeability, ultra-low loss, and high thermal stability. The saturation magnetization of the FeSiAl SMC increased, while the coercivity decreased due to the exchange coupling of the magnetic nanocrystalline particles. The total loss of the novel SMC decreased to 139.93 kW/m3 at 100 mT and 100 kHz, which is only one-third of that of common commercially available Sendust composites, while the permeability was up to 62 for the reduced demagnetization field. Furthermore, three-dimensional loss separation was performed based on the nonlinear regression method, and the complex permeability was separately addressed as the domain-wall movement and spin resonance parts. The minimum total loss was ascribed to the significantly reduced hysteresis loss and the slightly reduced eddy current loss, corresponding to the low coercivity (Hc = 0.341 Oe) and high impedance (|Z| = 67.1 MΩ). This was attributed to the improved magnetic properties and resistance of the insulation coating, which was related to the magnetic nanoparticles embedded in the insulation coating. The permeability was mainly derived from the spin resonance due to the complete insulation coating and ultrafine particles. This novel SMC with a phosphate insulation coating doped with magnetic NiFe 2 O 4 nanocrystalline particles provides a high-efficiency, high-frequency, and high-saturation soft magnetic device for switching power supplies, photovoltaic inverter boost inductors, and other applications.
研究领域:
材料科学
·
电磁学
✓ 已验证
DOI
高影响因子