Protection Properties of Advanced Textile Shields Determined in Frequency and Time Domain (original) (raw)

Conductive textile structures and their contribution to electromagnetic shielding effectiveness

Industria Textila, 2020

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 a...

Comparison of methods for evaluating the electromagnetic shielding of textiles

Vlakna a Textil

Materials with electromagnetic shielding efficiency are widely used to attenuate the strength of electromagnetic fields as functional elements in electrotechnic devices and also as supporting elements for electromagnetic interference reduction. One of modern application is not only technical protection, but also protection of human being while operating specific electric equipments. In these days, instead of metallic shields it is more common to use various types of textile materials due to their desirable flexibility and lightweight. The results of shielding effectiveness measurements depend on the method, frequency and properties of the material itself. The current state of work in the field of standardization and measurement methods for the shielding effectiveness of thin planar materials is presented in this paper. Testing of textile samples shielding was performed by different methods and scope of application, their limitations and possibilities for comparison of results are di...

Studies on Electromagnetic Shielding Effectiveness of Electrically Conductive Fabric

TJPRC, 2013

Due to rapid growth of the electronic industry and the widespread use of electronic equipments have led to many electromagnetic interference (EMI) problems like malfunctioning of an electrical circuit and the possibility of cancer. This can be prevented using electromagnetic shielding. Use of textiles as a shielding material gives an advantages of light weight and flexibility as compared to metal screens and the other traditional shielding materials. Many researchers have tried different methods to make textile material electrically conductive for electromagnetic shielding use. PC fabric was made electrically conductive by silver coating of different thickness using plasma technique and electromagnetic shielding effectiveness has been investigated in the present paper. It was observed that with increase in coating thickness, better shielding effectiveness is achieved.

Numerical and Experimental Study of the Shielding Effectiveness of Hybrid Fabrics

Vlakna a Textil

The electromagnetic interference shielding efficiency measurement needs to use special devices and in addition results are dramatically affected by applied measuring method. Measurements of surface or volume resistivity are simpler. It is known from theory that it is possible to measure characteristics of electrical part of electromagnetic field only at sufficiently high frequencies and therefore there should be mathematical relation between total shielding effectiveness SE [dB] and fabric resistivity or conductivity. One of modern application of materials with increased electromagnetic shielding efficiency is not only technical protection, but also protection of human being while operating specific electric equipments. The main aim of this work is investigation of the form of relation between electrical characteristics and total shielding effectiveness SE for special types of fabrics containing extremely thin metal fibers in its structure.

Protection Against Electromagnetic Radiation with Textile Material

2013

Today textiles are no more limited for wearing purpose only. The technological developments in recent years have developed technical textiles material, which can be used in various industries like automobile, advertising, agriculture, civil constructions, environmental protection, chemical, electronic, geo-textile, industrial coverings, medicals, printing, space, etc. This paper highlights the various textile material, their properties, manufacturing and application with special emphasis on role of textile material as an electromagnetic and electrostatic discharge protective device.

Effectiveness of Shielding Electromagnetic Radiation, and Assumptions for Designing the Multi-layer Structures of Textile Shielding Materials

Fibres & Textiles in Eastern Europe, 2009

In many cases, to obtain the required extent of protection against electromagnetic radiation (EMR) emitted by operating electrical and electronic devices, it is not enough to use only shielding materials that non-transmit the radiation as a results of its reflection, but it is in dispensable to use shields (materials) possessing the capability to reflect and absorb EMR at the same time. Depending on their practical use, such materials should be characterised by a high EMR absorption coefficient, even twice as high as their reflection coefficient within as wide a frequency band as possible. This paper presents assumptions for designing multi-layer textile-polymeric materials, the dominating feature of which that increases the shielding effectiveness consists in absorbing EMR as a result of so-called multiple internal reflection. Methods for testing the coefficients of reflection and transmission as well as the preliminary assessment of the test results concerning the EMR shielding ma...

Fiber-based structures for electromagnetic shielding – comparison of different materials and textile structures

Textile Research Journal, 2017

In this study, 32 different electro-conductive fabrics and seven different non-conductive fabrics were taken for an analysis of their electromagnetic shielding ability, electrical resistivity and air permeability. According to the present state of development of electromagnetic shielding textile structures, a diverse set of samples was selected, including stainless steel, copper, silver, aluminum, carbon and polypyrrole as a conductive component. The ASTM D4935 coaxial transmission line method was used to study the electromagnetic shielding and the ASTM D257 ring electrode method was used to evaluate the surface and volume electrical resistivity of all the samples. Air permeability was considered as an additional important parameter for the production of electromagnetic radiation protective fabrics designed for technical or clothing applications. It was confirmed that textile structures made of conventional textile fibers are transparent to an electromagnetic field. The electromagne...