scholarly journals The effects of metal type, number of layers, and hybrid yarn placement on the absorption and reflection properties in electromagnetic shielding of woven fabrics

2019 ◽  
Vol 14 ◽  
pp. 155892501986096 ◽  
Author(s):  
Ilkan Özkan ◽  
Abdurrahman Telli

In this study, stainless steel, copper, and silver wires were intermingled with two polyamide 6.6 filaments through the commingling technique to produce three-component hybrid yarns. The produced hybrid yarns were used as weft in the structure of plain woven fabric samples. The electromagnetic shielding effectiveness parameters of samples were measured in the frequency range of 0.8–5.2 GHz by the free space technique. The effects of metal hybrid yarn placement, number of fabric layers, metal types, and wave polarization on the electromagnetic shielding effectiveness and absorption and reflection properties of the woven fabrics were analyzed statistically at low and high frequencies separately. As a result, the samples have no shielding property in the warp direction. Metal types show no statistically significant effect on electromagnetic shielding effectiveness. However, fabrics containing stainless steel have a higher absorption power ratio than copper and silver samples. Double-layer samples have higher electromagnetic shielding effectiveness values than single-layer fabrics in both frequency ranges. However, the number of layers does not have a significant effect on the absorbed and reflected power in the range of 0.8–2.6 GHz. There was a significant difference above 2.6 GHz frequency for absorbed power ratio. An increase in the density of hybrid yarns in the fabric structure leads to an increase in the electromagnetic shielding effectiveness values. Two-metal placement has a higher absorbed power than the full and one-metal placements, respectively. The samples which have double layers and including metal wire were in their all wefts reached the maximum electromagnetic shielding effectiveness values for stainless steel (78.70 dB), copper (72.69 dB), and silver composite (57.50 dB) fabrics.

2018 ◽  
Vol 49 (3) ◽  
pp. 365-382 ◽  
Author(s):  
Jia-Horng Lin ◽  
Ting An Lin ◽  
Ting Ru Lin ◽  
Jia-Ci Jhang ◽  
Ching-Wen Lou

In this study, a composite plain material is composed of woven fabrics containing metal wire with shielding ability and polyester filament that can provide flexibility and far-infrared emissivity. Furthermore, a wrapping process is used to form metal/far-infrared–polyester wrapped yarns, which are then made into metal/far-infrared–polyester woven fabrics. The effects of using stainless steel wire, Cu (copper) wire, or Ni–Cu (nickel-coated copper) wire on the wrapped yarns and woven fabrics are examined in terms of tensile properties, electrical properties, and electromagnetic shielding effectiveness. Moreover, SS+Cu+Ni-Cu woven fabrics have maximum tensile strength, while SS+Ni-Cu woven fabrics have the maximum elongation and SS+Cu+Ni-Cu woven fabrics have the lowest surface resistivity. Stainless steel composite woven fabrics have far-infrared emissivity of 0.89 when they are composed of double layers. electromagnetic shielding effectiveness test results indicate that changing the number of lamination layers and lamination angle has a positive influence on electromagnetic shielding effectiveness of woven fabrics. In particular, SS+Cu+Ni-Cu woven fabrics exhibit electromagnetic shielding effectiveness of −50 dB at a frequency of 2000–3000 MHz when they are laminated with three layers at 90°.


2015 ◽  
Vol 749 ◽  
pp. 265-269 ◽  
Author(s):  
Jia Horng Lin ◽  
Ting An Lin ◽  
Chien Teng Hsieh ◽  
Jan Yi Lin ◽  
Ching Wen Lou

This study uses 0.08mm copper wire and nickel-coated copper wire as the core and 75 D far infrared filament as the wrapped material to manufacture Cu/FIR-PET wrapped yarn, Ni-Cu/FIR-PET wrapped yarn and Ni-Cu/Cu/FIR-PET wrapped yarn. The three optimum metallic/FIR-PET wrapped yarns are then weaving into Cu/FIR-PET woven fabrics, Ni-Cu/FIR-PET woven fabrics and Ni-Cu/Cu/FIR-PET woven fabrics. Tensile property of metallic/FIR-PET wrapped yarns, electrical resistance of metallic/FIR-PET wrapped yarns, surface resistivity of metallic/FIR-PET woven fabrics and electromagnetic shielding effectiveness of metallic/FIR-PET woven fabric are discussed. According to the results, the optimum tenacity and elongation are chosen as 7 turns/ cm, electrical resistance of Ni-Cu/Cu/FIR-PET wrapped presents the best value, Cu/FIR-PET woven fabric has the lowest surface resistivity and Ni-Cu/Cu/FIR-PET woven fabric shows the best EMSE at 37.61 dB when the laminating-layer number is double layer and laminating at 90 ̊. In this study, three kinds of metallic/FIR-PET woven fabrics are successfully manufactured and looking forward to applying on industrial domains.


2014 ◽  
Vol 910 ◽  
pp. 210-213 ◽  
Author(s):  
Jia Horng Lin ◽  
Ting An Lin ◽  
An Pang Chen ◽  
Ching Wen Lou

The electronic appliance is capable of emitting electromagnetic waves that will cause the damage of electrical equipment and influence peoples health. In this study, stain steel filament (SS filament) and 75D PET filament were used to manufacture SS/PET composite yarn The SS/PET composite yarn were made by the wrapping machine, which the core yarn is stain steel filament, wrapped yarn is 75D PET filament and the wrapping layers is varied as one and two. After that, the composite yarn is fabricated by the automatic sampling loom into composite woven fabrics. The composite SS/PET woven fabrics were under the tests of electromagnetic shielding effectiveness (EMSE) and air permeability. The test results revealed that the EMSE of the one-layer composite woven fabric is 9.5 dB at 900 MHz, but the EMSE decreases as test frequency increases. When laminating layer added to three layers, the EMSE raise up to 12.6 dB. The EMSE of composite woven fabric reached at 29.9 when the laminated angle is 45°. And the air permeability decreases as the laminate layer increases, which the thickness of sample affect air to pass through the sample.


2019 ◽  
Vol 50 (6) ◽  
pp. 830-846
Author(s):  
Yalan Yang ◽  
Jianping Wang ◽  
Zhe Liu ◽  
Zhujun Wang

Electromagnetic radiation is becoming increasingly serious around our living environment, which seriously endangers people's health and interferes with the operation of electronic equipment. The research and development of anti-electromagnetic radiation fabric have drawn more and more attention. However, the influencing rules and mechanisms of conductive fiber content, fabric tightness, warp–weft density, conductive yarn arrangement, weave type, and electromagnetic wave frequency on fabric electromagnetic shielding effectiveness have not been clarified. Therefore, in this study, a series of fabrics containing stainless steel fibers were produced. Meanwhile, the influencing rules of various factors on electromagnetic shielding effectiveness and the quantitative relationship between some factors and electromagnetic shielding effectiveness were discussed. The results showed that all factors had different degrees of influence on electromagnetic shielding effectiveness, and the relationship between electromagnetic shielding effectiveness and electromagnetic wave frequency could be approximately expressed as: [Formula: see text]. At the same time, the influencing mechanisms of various factors on electromagnetic shielding effectiveness were analyzed in combination with fabric microstructure and macrostructure, the intrinsic parameters of the fabric and the electromagnetic shielding effectiveness mechanism. The results are expected to provide a reference for the establishment of electromagnetic shielding fabric model and enterprise production.


2011 ◽  
Vol 239-242 ◽  
pp. 1994-1997 ◽  
Author(s):  
Ching Wen Lou ◽  
Yi Chang Yang ◽  
Chin Mei Lin ◽  
Ching Wen Lin ◽  
Lin Chao Chen ◽  
...  

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.


2020 ◽  
Vol 15 ◽  
pp. 155892502098595
Author(s):  
Metin Yuksek

The demand for multifunctional requirements in aerospace, military, automobile, sports, and energy applications has encouraged the investigation of new conductive composite fibers. This study focuses on the development of Vapor-grown carbon nanofibers (VGCNFs) filled Polyvinylidene Fluoride (PVDF) composite fibers. Polyvinylidene fluoride (PVDF) reinforced with (1, 3, 5, and 8 wt.%) carbon nanofibers were produced as a masterbatch. The production of PVDF and PVDF/CNF composite fibers have been done successfully by using melt spinning processing technique. Conductive woven fabrics were produced with composite fibers on handloom machines to measure electromagnetic interference (EMI) shielding efficiency. Tensile strength of fibers increased with increase in CNF loading up to 3%. The tensile strength displayed a decrease of 5% and 8% CNF loading. Electromagnetic shielding effectiveness (EMSE) of woven fabrics with composite fibers were tested by using the coaxial transmission line method for planar materials standard that is based on ASTM D 4935-10. The electromagnetic shielding effectiveness of woven fabric which is consist of conductive composite fibers were increased with increasing CNFs loading and amount of fabric layers. It can be seen that the woven fabrics displayed between 2–10 dB and 2–4 dB EMSE values in the 15–600 MHz and 600–3000 MHz-frequency range, respectively. Nevertheless, it was observed that conductive filler content, dispersion, and network formation within the composite fibers were highly influent on the electromagnetic shielding effectiveness performance of the structures.


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