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Growth of magnetic metals on carbon microspheres with synergetic dissipation abilities to broaden microwave absorption

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Journal of materials Science & technology 2022年第12期107卷 100-110页

作者： Biao Zhao Yang Li Qingwen Zeng Bingbing Fan Lei Wang Rui Zhang Renchao Che laboratory of Advanced materials Shanghai Key Lab of Molecular Catalysis and Innovative MaterialsFudan UniversityShanghai 200438China Department of materials Science Fudan UniversityShanghai 200438China Henan Key Laboratory of Aeronautical Materials and Application Technology School of Material Science and EngineeringZhengzhou University of AeronauticsZhengzhouHenan 450046China School of Material Science and Engineering Zhengzhou UniversityZhengzhouHenan 450001China State key laboratory of Solidification Processing Northwestern Polytechnical UniversityXi’an 710072China

Microwave absorption(MA) materials have been captured extensive attentions due to the serious electromagnetic(EM) pollution. Numerous interests focus on the MA performances of core-shell structural composites with magnetic constituents as cores and dielectric constituents as shells, which inevitably suppressed the magnetic coupling causing the decrease of magnetic loss to some extent. Herein, the coreshell structural carbon(C) microsphere/magnetic metal composites were fabricated through the combination of an electrostatic assembly approach and subsequent in-situ reduction reaction. The complex permittivity and permeability of core-shell C@magnetic metal composite system can be effective adjusted by the constituent and microstructure of shells. Thanks to the distinct magnetic coupling from the subtle designed structures and the promotion of the magnetic-dielectric synergy, the C@magnetic metal composite exhibited enhanced MA properties. The optimal reflection loss(RL) of C@Ni composite was-54.1 dB with a thickness of 3.4 mm, meanwhile the effective absorbing band could reach over 5.5 GHz at only a1.8 mm thickness. Broad absorption bandwidth with RL below-10 d B could achieve 6.0 GHz and 6.7 GHz for C@Co and C@Ni Co composites with a thin 2.1 mm thickness, respectively. Our exciting findings might lead a guide on the novel structure design for the functional core-shell structural composites used for microwave absorption.

关键词： Microwave absorption Core-shell structure C@magnetic metal composite Interfacial polarization Magnetic coupling

Development of acoustic liner in aero engine: A review

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Science China(Technological Sciences) 2020年第12期63卷 2491-2504页

作者： MA XuQiang SU ZhengTao Aviation key laboratory of Science and technology on materials and application Research for Vibration and Noise Reduction AECC Beijing Institute of Aeronautical MaterialsBeijing 100095China

Noise reduction for aircraft engine has attracted great concern due to the strict noise control regulation nowadays. Conventional perforated sheet-over-honeycomb acoustic liners have been widely used to attenuate turbofan engine noise. To dampen the broadband noise and resist the harsh service conditions with high temperature and pressure in modern turbofan engine,new acoustic liner concepts are proposed and evaluated in the latest decade. In this review,available studies regarding the recent development of liners are gathered. The paper starts with the introduction of acoustic absorption mechanism of local-reacting and extended-reacting liners. The progress of novel passive liners(e.g.,mesh-cap liner,variable-depth liner,metal foam liner,hybrid liner,etc.) is summarized. Furthermore,adaptive liners with tunable geometry dimension or bias flow are illustrated in details.Metamaterial is also mentioned as a hot candidate in the next generation of acoustic liners. Finally,this review identifies benefits and some technical challenges with the goal of unveiling the potential of novel acoustic liner technologies in aero engine.

关键词： aero engine noise acoustic liner Helmholtz resonators composites

Achieving ultra-broadband electromagnetic wave absorption in high-entropy transition metal carbides (HE TMCs)

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Journal of Advanced Ceramics 2022年第4期11卷 545-555页

作者： Weiming ZHANG Huimin XIANG Fu-Zhi DAI Biao ZHAO Shijiang WU Yanchun ZHOU Science and technology on Advanced Functional Composite laboratory Aerospace Research Institute of Materials&Processing TechnologyBeijing 100076China Henan Key Laboratory of Aeronautical Materials and Application Technology School of Material Science and EngineeringZhengzhou University of AeronauticsZhengzhou 450046China Zibo Firststar New Material Incorporated Co. Ltd.Zibo 255000China

Electronic devices pervade everyday life,which has triggered severe electromagnetic(EM)wave pollution.To face this challenge,developing EM wave absorbers with ultra-broadband absorption capacity is critically required.Currently,nano-composite construction has been widely utilized to realize impedance match and broadband absorption.However,complex experimental procedures,limited thermal stability,and interior oxidation resistance are still unneglectable issues.Therefore,it is appealing to realize ultra-broadband EM wave absorption in single-phase materials with good stability.Aiming at this target,two high-entropy transition metal carbides(HE TMCs)including(Zr,Hf,Nb,Ta)C(HE TMC-2)and(Cr,Zr,Hf,Nb,Ta)C(HE TMC-3)are designed and synthesized,of which the microwave absorption performance is investigated in comparison with previously reported(Ti,Zr,Hf,Nb,Ta)C(HE TMC-1).Due to the synergistic effects of dielectric and magnetic losses,HE TMC-2 and HE TMC-3 exhibit better impedance match and wider effective absorption bandwidth(EAB).In specific,the exclusion of Ti element in HE TMC-2 endows it optimal minimum reflection loss(RL_(min))and EAB of−41.7 dB(2.11 mm,10.52 GHz)and 3.5 GHz(at 3.0 mm),respectively.Remarkably,the incorporation of Cr element in HE TMC-3 significantly improves the impedance match,thus realizing EAB of 10.5,9.2,and 13.9 GHz at 2,3,and 4 mm,respectively.The significance of this study lays on realizing ultra-broadband capacity in HE TMC-3(Cr,Zr,Hf,Nb,Ta),demonstrating the effectiveness of high-entropy component design in tailoring the impedance match.

关键词： transition metal carbide(TMC) high-entropy ceramics electromagnetic(EM)wave absorption dielectric and magnetic loss coupling ultra-broadband absorption

High-entropy spinel ferrites MFe_(2)O_(4)(M=Mg,Mn,Fe,Co,Ni,Cu,Zn)with tunable electromagnetic properties and strong microwave absorption

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Journal of Advanced Ceramics 2022年第5期11卷 754-768页

作者： Jiabin MA Biao ZHAO Huimin XIANG Fu-Zhi DAI Yi LIU Rui ZHANG Yanchun ZHOU Henan Key Laboratory of Aeronautical Materials and Application Technology School of Materials Science and EngineeringZhengzhou University of AeronauticsZhengzhou 450046China Science and technology on Advanced Functional Composite laboratory Aerospace Research Institute of Materials&Processing TechnologyBeijing 100076China School of Material Science and Engineering Shaanxi University of Science and TechnologyXi'an 710021China School of materials Science and Engineering Luoyang Institute of Science and TechnologyLuoyang 471023China

Ferrites are the most widely used microwave absorbing materials to deal with the threat of electromagnetic(EM)pollution.However,the lack of sufficient dielectric loss capacity is the main challenge that limits their applications.To cope with this challenge,three high-entropy(HE)spineltype ferrite ceramics including(Mg_(0.2)Mn_(0.2)Fe_(0.2)Co_(0.2)Ni_(0.2))Fe_(2)O_(4),(Mg_(0.2)Fe_(0.2)Co_(0.2)Ni_(0.2)Cu_(0.2))Fe_(2)O_(4),and(Mg_(0.2)Fe_(0.2)Co_(0.2)Ni_(0.2)Zn_(0.2))Fe_(2)O_(4)were designed and successfully prepared through solid state synthesis.The results show that all three HE MFe_(2)O_(4) samples exhibit synergetic dielectric loss and magnetic loss.The good magnetic loss ability is due to the presence of magnetic components;while the enhanced dielectric properties are attributed to nano-domain,hopping mechanism of resonance effect and HE effect.Among three HE spinels,(Mg_(0.2)Mn_(0.2)Fe_(0.2)Co_(0.2)Ni_(0.2))Fe_(2)O_(4)shows the best EM wave absorption performance,e.g.,its minimum reflection loss(RL_(min))reaches-35.10 dB at 6.78 GHz with a thickness of 3.5 mm,and the optimized effective absorption bandwidth(EAB)is 7.48 GHz from 8.48 to 15.96 GHz at the thickness of 2.4 mm.Due to the easy preparation and strong EM dissipation ability,HE MFe_(2)O_(4) are promising as a new type of EM absorption materials.

关键词： high-entropy ceramics(HECs) spinel-type ferrite electromagnetic(EM)wave absorption dielectric loss magnetic loss

Microwave synthesis of chain-like zircona nanofibers through carbon-induced self-assembly growth

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Frontiers of materials Science 2017年第4期11卷 353-357页

作者： Wanyu ZHAO Jian LI Bingbing FAN Gang SHAO Hailong WANG Bozhen SONG Shengnan WEI Rui ZHANG School of materials Science and Engineering Zhengzhou University Zhengzhou 450001 China henan key laboratory of aeronautical Material and application technology Zhengzhou University of Aeronautics Zhengzhou 450046 China

Chain-like zircona （ZrO2） nanofibers were prepared by microwave sinter- ing without any surfactants or solid templates. Microwave sintering was conducted in a multimode microwave cavity with TE666 resonant mode at 2.45 GHz. Carbon particles were used to activate unique thermal processes when mixed with ZrO2 precursor. The sintering condition was at 1300℃ for 10 min. Samples were characterized by XRD, SEM, TEM techniques. It was found that both monolithic and tetragonal ZrO2 co-existed in samples prepared from the mixture of ZrO2 precursors and carbon by either microwave or conventional sintering. Only m-ZrO2 exists in samples prepared by ZrO2 precursors without carbon. ZrO2 appeared as chain-like nanofibers, which might be attributed to a so- called carbon-induced self-assembly growth mechanism.

关键词： ZrO2 chain-like nanofibers microwave sintering carbon-induced self-assembly growth

Achieving strong microwave absorption capability and wide absorption bandwidth through a combination of high entropy rare earth silicide carbides/rare earth oxides

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Journal of materials Science & technology 2020年第12期47卷 216-222页

作者： Heng Chen Biao Zhao Zifan Zhao Huimin Xiang Fu-Zhi Dai Jiachen Liu Yanchun Zhou Science and technology on Advanced Functional Composite laboratory Aerospace Research Institute of Materials&Processing TechnologyBeijing 100076China key laboratory of Advanced Ceramics and Machining technology of Ministry of Education School of Materials Science and EngineeringTianjin UniversityTianjin 300072China Henan Key Laboratory of Aeronautical Materials and Application Technology School of Material Science and EngineeringZhengzhou University of AeronauticsZhengzhou 450046China

Developing electromagnetic(EM) wave absorbing materials with low reflection coefficient and optimal operating frequency band is urgently needed on account of the increasingly serious EM pollution. However, the applications of common EM absorbing materials are encumbered by poor high-temperature stability, poor oxidation resistance, narrow absorption bandwidth or high density. Herein, the strong EM absorption capability and wide efficient absorption bandwidth of high entropy ceramics are reported for the first time, which are designed by a combination of the novel high entropy(HE) rare earth silicide carbides/rare earth oxides(RE3 Si2 C2/RE2 O3). Three HE powders, i.e., HERSC-1(HE(Tm0.2 Y0.2 Dy0.2 Gd0.2 Tb0.2)3 Si2 C2),HERSC-2 HE(Tm0.2 Y0.2 Dy0.2 Gd0.2 Tb0.2)3 Si2 C2/HE(Tm0.2 Y0.2 Dy0.2 Gd0.2 Tb0.2)2 O3) and HERSC-3(HE(Tm0.2 Y0.2 Dy0.2 Gd0.2 Tb0.2)3 Si2 C2/HE(Tm0.2 Y0.2 Dy0.2 Gd0.2 Tb0.2)2 O3), are synthesized. Although HERSC-1 exhibits a limited absorption effect(the minimum reflection loss(RLmin) is-11.6 d B at 3.4 mm) and a relatively narrow effective absorption bandwidth(EAB) of 1.7 GHz, the optimal absorption RLminvalue and EAB of HERSC-2 and HERSC-3 are-40.7 d B(at 2.9 mm), 3.4 GHz and-50.9 d B(at 2.0 mm), 4.5 GHz,respectively, demonstrating strong microwave absorption capability and wide absorption bandwidth.Considering the better stability, low density and strong EM absorption effect, HE ceramics are promising as a new type of EM absorbing materials.

关键词： High entropy ceramics Rare earth silicide carbides Absorption materials Reflection loss Interfacial polarization

In-situ grown Ni Co bimetal anchored on porous straw-derived biochar composites with boosted microwave absorption properties

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International Journal of Minerals,Metallurgy and materials 2023年第3期30卷 515-524页

作者： Yuanyuan Zhou Zhongyi Bai Xiangyang Yang Wei Liu Bingbing Fan Zhikai Yan Xiaoqin Guo Henan Key Laboratory of Aeronautical Materials and Application Technology School of Material Science and EngineeringZhengzhou University of AeronauticsZhengzhou 450046China School of Chemical&Environmental Engineering China University of Mining&Technology(Beijing)Beijing 100083China School of Material Science and Engineering Zhengzhou UniversityZhengzhou 450001China

With the gradually increasing protection awareness about electromagnetic pollution,the demand for absorbing materials with renewability and environmental friendliness has attracted widespread attention.In this work,composites consisting of straw-derived biochar combined with NiCo alloy were successfully fabricated through high-temperature carbonization and subsequent hydrothermal reaction.The electromagnetic parameters of the porous biocarbon/NiCo composites can be effectively modified by altering their NiCo content,and their improved absorbing performance can be attributed to the synergy effect of magnetic-dielectric characteristics.An exceptional reflection loss of-27.0 dB at 2.2 mm thickness and an effective absorption bandwidth of 4.4 GHz(11.7-16.1 GHz)were achieved.These results revealed that the porous biocarbon/NiCo composites could be used as a new generation absorbing material because of their low density,light weight,excellent conductivity,and strong absorption.

关键词： straw-derived biochar microwave absorption interfacial polarization magnetic loss bimetallic NiCo impedance matching

Tribological properties in seawater for Ti/TiCN coatings on Ti6Al4V alloy by arc ion plating with different carbon contents

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Rare Metals 2017年第11期36卷 858-864页

作者： Jin-Long Li Gang-Yi Cai Hua-Sheng Zhong Yong-Xin Wang Jian-Min Chen key laboratory of Marine materials and application Technologies Zhejiang Key Laboratory of Marine Materials and Protection Technologies Ningbo Institute of Materials Technologies and Engineering Chinese Academy of Sciences School of Mechanical and Electrical Engineering Henan University of Technology

TiCN coatings incorporated with Ti buffer layer were deposited on Ti6A14V alloy by arc ion plating. The carbon content in TiCN coatings was varied by controlling flow rates of C2H2 in reactive gas. The Ti/TiCN coatings have a typical structure of columnar crystal with a total thickness of about 2 pro. The elements of Ti, C and N are present as TiN and TiC in TiCN coatings. A little free carbon appears with carbon content increasing in TiCN coatings. For the TiCN coatings, the hardness, friction coefficient and wear rate decrease with the increase in carbon content. In seawater, both friction coefficient and wear rate have an obvious decrease at lower carbon content compared with those in atmosphere. However, the friction coefficient and wear rate only have a slight decrease, while the carbon content reaches or exceeds 10 at% in Ti/TiCN coatings.

关键词： Ti/TiCN coatings Arc ion plating Hardness Seawater Wear

A novel MgF2/PDA/S-HA coating on the bio-degradable ZE21B alloy for better multi-functions on cardiovascular application

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Journal of Magnesium and Alloys 2023年第2期11卷 480-492页

作者： Yang Yu Shi-Jie Zhu Hao-Tian Dong Xue-Qi Zhang Jing-An Li Shao-Kang Guan School of materials Science and Engineering&henan key laboratory of Advanced Magnesium Alloy&key laboratory of materials Processing and Mold technology(Ministry of Education) Zhengzhou UniversityZhengzhou 450001China

Recently, functional molecules such as Polydopamine(PDA), Hyaluronic Acid(HA) and heparin have been widely studied in the field of surface modification of magnesium(Mg) alloy stents for better degradation behavior and biocompatibility, but their further application is limited by undesirable anticoagulant function, uncontrollable degradation and easy bleeding, respectively.Regarding to this consideration, a magnesium Fluoride/Polydopamine/Sulphonated hyaluronic acid(Mg F2/PDA/S-HA) composite coating was successfully prepared by applying S-HA with sulfur content of 9.71 wt% on the surface of ZE21B alloy in this study. The results showed that the composite coating with a unique mesh structure not only inherited the anticoagulant effect of sulfonic acid group and the excellent cyto-compatibility of S-HA with high sulfur content, but also significantly improved the corrosion performance of ZE21B alloy.These results indicate a great application potential of the composite coating in the field of cardiovascular biomaterials.

关键词： Bio-degradable magnesium alloy Cardio-vascular stents Composite coating Sulphonated hyaluronic acid