Effective frequency range of ladder network realization for complex permeability of magnetic sheets

For the sake of thinner electromagnetic wave absorbers used in quasimicrowave band, planar anisotropy carbonyl-iron (PACI) coated with amorphous SiO2 particles as absorber and paraffin as matrix were prepared. The complex permeability, complex permittivity and microwave absorption properties were investigated in the frequency range of 0.1-18 GHz. Both the real parts of permeability and permittivity are increased with the increasing of PACI/SiO2 particles volume concentrations. The minimum reflection loss shifts to the low frequency region with increase in PACI/SiO2 particles volume concentrations. The decrease of matching frequency could be well explained by the increasing of and . The PACI/SiO2 core-shell material exhibits great potential in application absorbers in quasimicrowave frequency range.

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Magnetic and Microwave Properties of Polycrystalline Gadolinium Iron Garnet

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.268.287 ◽

2017 ◽

Vol 268 ◽

pp. 287-291 ◽

Cited By ~ 5

Author(s):

Farah Nabilah Shafiee ◽

Raba’ah Syahidah Azis ◽

Ismayadi Ismail ◽

Rodziah Nazlan ◽

Idza Riati Ibrahim ◽

...

Keyword(s):

Magnetic Loss ◽

Ambient Air ◽

High Energy ◽

Microwave Properties ◽

Complex Permeability ◽

Frequency Range ◽

Mixed Powder ◽

Band Frequency ◽

Suitable Material ◽

Microwave Loss

The microwave loss in nanosized GdIG particles synthesized using mechanical alloying technique was investigated. There were very few of research on the microwave properties of nanosized particle GdIG and there is no attempt investigating on the material at C-band frequency range and its correlation with the microstructure. Gadolinium (III) iron oxide and iron (III) oxide, α-Fe2O3 were used as the starting materials. The mixed powder was then milled in a high-energy ball mixer/mill SPEX8000D for 3 hours. The samples were sintered at temperature 1200°C for 10 hours in an ambient air environment. The phase formation of the sintered samples was analyzed using a Philips X’Pert Diffractometer with Cu-Kα radiation. Complex permeability constitutes of real permeability and magnetic loss factor were measured using an Agilent HP4291A Impedance Material Analyzer in the frequency range from 10 MHz to 1 GHz. A PNA-N5227 Vector Network Analyzer (VNA) was used to obtain the information on ferromagnetic linewidth broadening, ΔH that represents the microwave loss in the samples in in frequency range of 4 to 8 GHz (C-band). The ΔH value was calculated from the transmission (S21) data acquired from VNA. The single phase GdIG showed low initial permeability and low magnetic loss when applied with low-frequency range energy. From these data, it is validated that GdIG is a suitable material for microwave devices for the high-frequency range.

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SiC Micro-Threads Prepared within the Carbon Fiber Felt

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.368-372.843 ◽

2008 ◽

Vol 368-372 ◽

pp. 843-845

Author(s):

Feng Yuan ◽

Hong Jie Wang ◽

Zhi Hao Jin

Keyword(s):

Carbon Fiber ◽

Three Dimensional ◽

Nitrogen Pressure ◽

Complex Permeability ◽

Similar Form ◽

Frequency Range ◽

Band Frequency ◽

X Band ◽

Carbon Fiber Felt ◽

Low Nitrogen

Polyacrylonitrile (PAN) based carbon fiber felt which contains abundant various SiC microthreads and some other microstructures was prepared through sintering the pretreated felt at high temperature at low nitrogen pressure. XRD, SEM, TEM, HRTEM analyses for the sintered felt were carried out to study its components and microstructures. There are SiC nanothreads, SiC submicron threads, SiC micron threads and a few SiO2 two- or three-dimensional microstructures (possibly intermix with the similar form of SiC) existed within the inner hollow spaces of the felt. The complex permittivity, complex permeability of the sample in the X-band frequency range were obtained.

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Effect of Sendust Particle Size on Absorption Characteristics of Composite Electromagnetic Wave Absorber

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.421-422.451 ◽

2009 ◽

Vol 421-422 ◽

pp. 451-454

Author(s):

Kenji Sakai ◽

Yoichi Wada ◽

Yuuki Sato ◽

Shinzo Yoshikado

Keyword(s):

Particle Size ◽

Electromagnetic Wave ◽

Return Loss ◽

Single Layer ◽

Complex Permeability ◽

Wave Power ◽

Flexible Design ◽

Frequency Range ◽

Polystyrene Resin ◽

Absorption Characteristics

The effects of the particle size of sendust, which is an alloy of Al 5%, Si 10%, and Fe 85%, on the absorption characteristics of composite electromagnetic wave absorbers made of polystyrene resin and sendust were investigated in the frequency range from 1 to 40 GHz. The size of sendust particles was varied between approximately 5 and 20 m. A metal-backed single-layer absorber made of 20 m sendust particles absorbed more than 99% of electromagnetic wave power at frequencies above 20 GHz. Meanwhile, a composite made of 5 m particles exhibited a return loss of less than −20 dB in the frequency range of not only several GHz but also above 30 GHz. In addition, the relative complex permeability r* was shown to be controlled by adjusting the particle size of sendust, and an electromagnetic wave absorber with a flexible design was proposed.

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Preparation and Electromagnetic Properties of CIP/SiO2/PANI Composites

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.834-836.187 ◽

2013 ◽

Vol 834-836 ◽

pp. 187-190

Author(s):

Ming Ming Wang ◽

Zhong Lun Zhang ◽

Wan Jun Hao ◽

Guo Yan Hou ◽

Zhi Jun Xin ◽

...

Keyword(s):

Dielectric Loss ◽

In Situ Polymerization ◽

Magnetic Loss ◽

Electromagnetic Properties ◽

Complex Permeability ◽

Core Shell ◽

Network Analyzer ◽

Frequency Range ◽

Xrd Patterns

CIP particles first were coated with SiO2 shell by the Stober process , then grafted the polyaniline by in-situ polymerization to prepare CIP/SiO2/PANI core-shell composites. The CIP/SiO2/PANI composites are composed the dielectric loss properties with the the magnetic loss properties, the morphologystructure and electromagnetic properties are characterized by SEMXRD and vector network analyzer, respectively. It is observed that SiO2 and PANI are on the surface of CIP particles, XRD patterns further confirm that the CIP/SiO2/PANI composites are synthesized successfully, and that interaction between components exist in the polymerization. In comparison with CIP, the complex permittivity of CIP/SiO2/PANI composites have certain enhancement in 2-18GHz frequency range, but it has a very small impact on the complex permeability.

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The effective frequency range of an active suspended handle based on the saturation effects of a piezo stack actuator

Journal of Vibration and Control ◽

10.1177/1077546315585218 ◽

2016 ◽

Vol 23 (5) ◽

pp. 752-769 ◽

Cited By ~ 3

Author(s):

Ahmad Zhafran Ahmad Mazlan ◽

Zaidi Mohd Ripin

Keyword(s):

Excitation Frequency ◽

Saturation Effect ◽

Feedback Gain ◽

Operating Speed ◽

Frequency Range ◽

Effective Frequency ◽

Novel Approach ◽

Saturation Effects ◽

Force Displacement ◽

Proportional Feedback

This paper presents a novel approach to the design of an active suspended handle by identifying the effective frequency range, based on the saturation effects of the piezo stack actuator, in terms of the force-displacement-voltage relationship as a function of the excitation frequency. The effective range allows for proper matching between the operating speed of the machine and the suspended handle. A model of the active suspended handle was developed, which took into account the non-linear saturation effect of the piezo stack actuator. A proportional-integral-derivative controller generated the counter voltage for the piezo stack actuator, using a proportional feedback gain (P) step up method, in order to attenuate the vibration transmitted to the handle. By including the saturation effect, the Pearson’s correlation coefficient ( R2) of the model improved to 0.97, within the frequency range of 50 ∼ 500 Hz. Using this approach, we identified that the effective frequency range of isolation with transmissibility less than unity is between 250 ∼ 450 Hz. The active suspended handle was attached to a die grinder with a nominal operating speed of 25000 rpm and the vibration transmitted from the die grinder to the handle was reduced by 91%.

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Design of An Ultra-Thin and Broadband Absorption Materials For Middle-Temperature Applications

10.21203/rs.3.rs-200487/v1 ◽

2021 ◽

Author(s):

Yanmin Jia ◽

Zhaoning Yang ◽

Lu Gao ◽

Wei Ren ◽

Ruiduan Zhang ◽

...

Keyword(s):

Reflection Loss ◽

Frequency Selective Surface ◽

Complex Permeability ◽

Frequency Range ◽

Broadband Absorption ◽

Radar Absorbing Material ◽

Temperature Environment ◽

Absorbing Material ◽

Relationship Of ◽

The Relationship

Abstract A radar absorbing material (RAM) is designed based on the magnetic ceramic and frequency selective surface (FSS). The phase composition and micromorphology were characterized, respectively. The complex permittivity and complex permeability of magnetic ceramic were tested and studied from 25 ℃ to 500 ℃ temperature. Based on the experimental and simulation results, the changes of reflection loss along with the structure parameters of RAM are analyzed at 500 ℃. The relationship of reflection loss varies with temperature are studied. The analytical results show that the absorption property of the RAM increases with the increase of temperature. An optimal absorption of RAM is obtained at 500℃. When the thickness of RAM is 1.5 mm, the reflection loss lower than -10 dB can be obtained in the frequency range from 8.2 ~ 16 GHz. More than 90% microwave energy can be consumed in the RAM which may be applied in the high temperature environment.

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