Study on Electromagnetic Shielding Effectiveness of Nickel Fiber-Filled Cement

2010 ◽  
Vol 168-170 ◽  
pp. 997-1000 ◽  
Author(s):  
Guo Xuan Xiong ◽  
Zhi Bin Zhang ◽  
Min Deng
Keyword(s):  
Portland Cement ◽  
Electromagnetic Shielding ◽  
Shielding Effectiveness ◽  
Frequency Range ◽  
Shielding Properties ◽  
Electromagnetic Shielding Effectiveness ◽  
Fiber Thickness

The cement-based composite shielding materials was prepared using portland cement and nickel fiber. The effects of dispersive manner, contents of nickel fiber, thickness of specimens on shielding properties and conductivity were studied in a frequency range of 100 KHz~1.5 GHz. With the contents of nickel fiber by ultrasonic dispersed at 5 vol.% and specimen’s thickness of 10 mm, the conductivity is 2.58×10-3 S•cm-1 and maximum shielding effectiveness is 47.8 dB, average shielding effectiveness reaches about 45.9 dB for cement-based composites.

Effectiveness of Low Frequency Electromagnetic Shielding of Concrete with the Functionally Primitives Materials of Short Carbon Fibers and Graphite

2011 ◽  
Vol 189-193 ◽  
pp. 4297-4303 ◽  
Author(s):  
Fa Qin Dong ◽  
Qiong Si
Keyword(s):  
Carbon Fibers ◽  
Low Frequency ◽  
Electromagnetic Shielding ◽  
Shielding Effectiveness ◽  
Frequency Range ◽  
Shielding Properties ◽  
Electromagnetic Shielding Effectiveness ◽  
Short Carbon

The electromagnetic shielding properties of short carbon fibers and graphite concrete were investigated, and the influence of the contents of the short carbon fibers and graphite on the electromagnetic shielding effectiveness of the concrete in low frequency was studied. The mechanism causing the influence of the short carbon fibers adulteration on the electromagnetic shielding effectiveness of the graphite concrete at low frequency was investigated. The maximum electromagnetic shielding effectiveness was up to 8.5dB in the low frequency range of 1MHz～1.8GH. The results of the investigation provide the basis for further designing and producing of high-powered electromagnetic shielding concrete at low frequency.

scholarly journals Conductive textile structures and their contribution to electromagnetic shielding effectiveness

2020 ◽  
Vol 71 (05) ◽  
pp. 432-437
Author(s):  
Ion Razvan Radulescu ◽  
Lilioara Surdu ◽  
Bogdana Mitu ◽  
Cristian Morari ◽  
Marian Costea ◽  
...  
Keyword(s):  
Electromagnetic Compatibility ◽  
Modern Technology ◽  
Electromagnetic Shielding ◽  
Shielding Effectiveness ◽  
Frequency Range ◽  
Conductive Coatings ◽  
Tem Cell ◽  
Conductive Yarns ◽  
Conductive Textile ◽  
Electromagnetic Shielding Effectiveness

Fabrics for electromagnetic shielding are especially relevant in nowadays context, contributing to human’s protection and wellbeing and to proper functioning of electronic equipment, in relation to electromagnetic compatibility. Fabrics with electromagnetic shielding properties employ two main technologies, namely insertion of conductive yarns and application of conductive coatings. Magnetron sputtering is a modern technology to enable conductive coatings with thickness in the range of nanometers onto fabrics. This paper aims to analyze contribution of various conductive textile structures out of both fabrics with inserted conductive yarns and coatings to Electromagnetic shielding effectiveness (EMSE). EMSE was measured in the frequency range of 0.1–1000 MHz by using a TEM cell according to standard ASTM ES-07. Results show a gain of 10–25 dB when introducing silver yarns in warp/ weft direction, a variation of 5–35 dB between conductive yarns out of silver and stainless steel and an up to 12 dB gain out of thin copper coating by magnetron plasma onto the fabrics with inserted conductive yarns

Electromagnetic shielding performance of three-dimensional woven fabrics with copper-based hybrid yarn in X-band frequency range

2018 ◽  
Vol 49 (4) ◽  
pp. 484-502 ◽  
Author(s):  
Dharmendra Nath Pandey ◽  
Arindam Basu ◽  
Pramod Kumar ◽  
Himangshu B Baskey
Keyword(s):  
Cotton Fabric ◽  
Three Dimensional ◽  
Electromagnetic Shielding ◽  
Shielding Effectiveness ◽  
Frequency Range ◽  
Structural Configuration ◽  
Band Frequency ◽  
Hybrid Yarn ◽  
X Band ◽  
Electromagnetic Shielding Effectiveness

This study involves a comprehensive evaluation of electromagnetic shielding characteristics of multilayer three-dimensional conductive fabrics by using cotton/copper wrapped hybrid yarn in X band frequency range. Five, three-dimensional fabrics with different structural configuration, such as orthogonal, angle interlock, cellular spacer, multi-tubular spacer, and contour were produced. Three different series of all five structures was also developed using pure cotton fabric, conductive hybrid yarn in weft and one-third hybrid yarn and two-third cotton yarn in warp Also, the effect of vertical and horizontal polarization of electromagnetic waves on electromagnetic shielding effectiveness was studied. The comparative analysis of reflectance transmittance and absorption behavior was also undertaken. The results indicate that pure cotton fabric (A series) does not have electromagnetic shielding capabilities. The difference between the electromagnetic shielding effectiveness values in vertical and horizontal planes of fabrics, having conductive hybrid yarn in weft direction (B series), showed significantly better results on the vertical plane in comparison to that on the horizontal plane. Fabric containing conductive hybrid yarn in both warp and weft (C series) exhibits consistent electromagnetic shielding effectiveness in both the planes. It is worth mentioning that the structural configuration in all five three-dimensional fabrics in B and C series has shown differential trends of electromagnetic shielding effectiveness in terms of reflectance, transmittance and absorption behavior. They are also found to be statistically significant. Finally, it is concluded that the conductive 3-D multilayer system develops special protective capabilities, mostly due to its larger surface area.

Electromagnetic Shielding Effectiveness and Manufacture Technique of Functional Metal Composite Knitted Fabrics

2014 ◽  
Vol 910 ◽  
pp. 262-265
Author(s):  
Jia Horng Lin ◽  
Zhi Cai Yu ◽  
Jian Fei Zhang ◽  
Ching Wen Lou
Keyword(s):  
Stainless Steel ◽  
Electromagnetic Shielding ◽  
Metal Composite ◽  
Shielding Effectiveness ◽  
Frequency Range ◽  
Knitted Fabrics ◽  
Steel Wires ◽  
Core Yarn ◽  
Composite Fabrics ◽  
Electromagnetic Shielding Effectiveness

In order to fabricate fabrics with electromagnetic shielding effectiveness (EMSE) and other function, we fabricated Crisscross-section polyester /antibacterial nylon / stainless steel wires (CSP/AN/SSW) composite yarns with stainless wires as core yarn, antibacterial nylon and crisscross-section polyester as inner and out wrapped yarns, respectively. Knitted fabrics were fabricated with the metal composite yarns with wrap amount of 8 turns/cm on a circular knitted machine. Furthermore, the EMSE of the metal composite fabrics were evaluated by changing the lamination amounts and lamination angles. The results show that when the lamination amount was four, lamination angles were 0°/45°/90°/-45°, the EMSE of the fabrics reached to-10--20 dB in the frequency range of 300 KHz to 3 GHz.

scholarly journals Investigation on antimicrobial activity and electromagnetic shielding effectiveness of metal composite single jersey fabrics

2019 ◽  
Vol 14 ◽  
pp. 155892501989598
Author(s):  
İlkan Özkan
Keyword(s):  
Vertical Direction ◽  
Electromagnetic Shielding ◽  
Activity Level ◽  
Test Method ◽  
Metal Composite ◽  
Shielding Effectiveness ◽  
Shielding Properties ◽  
Composite Fabrics ◽  
Electromagnetic Shielding Effectiveness ◽  
Single Jersey

In this study, antimicrobial and electromagnetic shielding properties of metal composite single jersey fabrics were investigated. For this purpose, stainless steel wire, copper wire, and metalized silver polyamide filament were commingled with textured polyester. The composite yarns were knitted to single jersey fabrics. Electromagnetic shielding effectiveness of samples was measured according to free space test method between 0.8 and 5.2 GHz frequency range. In addition, antibacterial and antifungal activity tests were performed for the overall technical characterization of composite fabrics. The effects of metal type, filament form on electromagnetic shielding effectiveness, and antimicrobial properties were examined. All composite fabrics showed electromagnetic shielding properties at different levels up to 35 dB in vertical direction. Fabrics including metalized multifilament yarn exhibit higher electromagnetic shielding effectiveness in both vertical and horizontal directions. In addition, antibacterial activity level of metalized silver polyamide and copper composite fabrics reached up to 99% against Klebsiella pneumoniae and Staphylococcus aureus. Furthermore, Aspergillus niger could not grow on these composite fabrics.

The Influence of Fabric Structures of the Woven Fabrics on Electromagnetic Shielding Effectiveness

2011 ◽  
Vol 239-242 ◽  
pp. 1994-1997 ◽  
Author(s):  
Ching Wen Lou ◽  
Yi Chang Yang ◽  
Chin Mei Lin ◽  
Ching Wen Lin ◽  
Lin Chao Chen ◽  
...  
Keyword(s):  
Stainless Steel ◽  
Electromagnetic Interference ◽  
Woven Fabrics ◽  
Electromagnetic Shielding ◽  
Shielding Effectiveness ◽  
Frequency Range ◽  
Fabric Structures ◽  
Electromagnetic Shielding Effectiveness

Stainless steel (SS) blended yarns with electromagnetic interference (EMI) were made into woven fabrics, after which the fabrics were evaluated with electromagnetic shielding effectiveness (EMSE). Parameters of laminated angle and the lamination number layers affected the fabrics’ EMSE differently. In addition, density of unidirectional SS yarns affected EMSE in frequency range of 200 to 500 MHz , so as the density of cross SS yarns on a frequency over 1000 MHz.

scholarly journals Multilayer-Structured Wood Electroless Cu–Ni Composite Coatings for Electromagnetic Interference Shielding

Coatings ◽  
2020 ◽  
Vol 10 (8) ◽  
pp. 740
Author(s):  
Yanfei Pan ◽  
Dingwen Yin ◽  
Xiaofang Yu ◽  
Nanyi Hao ◽  
Jintian Huang
Keyword(s):  
Surface Roughness ◽  
Surface Morphology ◽  
Electromagnetic Interference ◽  
Composite Coatings ◽  
Electromagnetic Shielding ◽  
Shielding Effectiveness ◽  
Frequency Range ◽  
Electromagnetic Interference Shielding ◽  
Electromagnetic Shielding Effectiveness ◽  
The Ideal

The lightweight multilayer-structured electromagnetic interference shielding composite coatings with controllable electromagnetic gradient on wood surface were prepared via a simple multiple electroless copper–nickel (Cu–Ni) approach. The surface morphology, conductivity, hydrophobicity property and electromagnetic shielding effectiveness of the composite coatings were investigated. The surface roughness and conductivity of the composite coatings were enhanced with the increase in the number of depositions. The surface morphology demonstrated that the roughness was decreased with the process of multiple electroless. The coatings were compact and homogeneous as the deposition run was three. Here, the Sa (Sa illustrated Surface Roughness) value of coatings was 4.497 μm. The ideal conductivity of composite coatings can be obtained as the number of depositions was four. Electromagnetic shielding effectiveness reached average 90.69 dB in the frequency range from 300 kHz to 2.0 GHz. This study provides a new pathway for fabricating lightweight multilayer-structured electromagnetic interference shielding with controllable electromagnetic gradient and hydrophobic composite coatings-based wood.

Electromagnetic shielding and far infrared composite woven fabrics: Manufacturing technique and function evaluation

2016 ◽  
Vol 87 (16) ◽  
pp. 2039-2047 ◽  
Author(s):  
Jia-Horng Lin ◽  
Po-Wen Hwang ◽  
Chien-Teng Hsieh ◽  
Yi-Jun Pan ◽  
Yueh-Sheng Chen ◽  
...  
Keyword(s):  
High Frequency ◽  
Far Infrared ◽  
Woven Fabrics ◽  
Electromagnetic Shielding ◽  
Function Evaluation ◽  
Shielding Effectiveness ◽  
Frequency Range ◽  
Blended Yarn ◽  
And Function ◽  
Electromagnetic Shielding Effectiveness

This study prepares and explores the properties of three types of woven fabrics that have electromagnetic shielding effectiveness (EMSE), far infrared (FIR) emissivity, or both (EMSE/FIR). The EMSE woven fabrics use stainless steel (SS) staple blended yarn and the FIR woven fabrics use FIR polyester filaments. The woven fabrics are made with various structures, densities, lamination layers, and warp/weft arrangements in order to yield the optimum EMSE and FIR emissivity. The experimental results show that an increase in SS content slightly increases the EMSE at the frequency range between 300 and 600 MHz, but does not significantly increase the EMSE at a high frequency of between 2000 and 2200 MHz. However, using SS staple blended yarn for both the warp and the weft significantly increases the EMSE by between −8 and −16 dB. The FIR emissivity increases as a result of an increasing amount of FIR polyester filament and reaches the optimum, 0.88.

Electroless Plating Nickel Film on Surface of Epoxy Resin and Evaluation of its Electromagnetic Shielding Effectiveness

2011 ◽  
Vol 148-149 ◽  
pp. 963-967
Author(s):  
Peng Jin ◽  
Shi Yun Dong ◽  
Bin Shi Xu ◽  
Zhan Yong Song
Keyword(s):  
Epoxy Resin ◽  
Electroless Plating ◽  
Electroless Deposition ◽  
Nickel Coating ◽  
Electromagnetic Shielding ◽  
Shielding Effectiveness ◽  
Frequency Range ◽  
Electromagnetic Shielding Effectiveness ◽  
Optic Microscopy ◽  
Scanning Electron

Nickel coating was prepared on surface of Epoxy Resin plate by electroless plating process. Surface and section morphologies of the coatings were observed by scanning electron microscopy (SEM) and metallographic optic microscopy. Electromagnetic shielding effectiveness was evaluated via flanged coaxial electromagnetic shielding effectiveness tester. The results showed that the surface of the nickel coating prepared by electroless plating process was smooth, and its structure was fine and compact. The electroless deposition rate of the nickel coating reached at 12μm/h. In the frequency range of 300 kHz to 100MHz the electromagnetic shielding effectiveness of the nickel coating was above 60dB, and in the frequency range of 100MHz to 1.5GHz the electromagnetic shielding effectiveness of the nickel coating was above 44dB.

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