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In this research work, copper core yarns with cotton/polyester sheaths were produced by friction spinning machines and their woven fabrics were made by looms with varying fabric structures for electromagnetic (EM) shielding purposes. The effect of varying structures, varying materials, varying numbers of layers, core sheath ratio, and lay-up angle on EM shielding effectiveness were studied. The shielding effectiveness of copper core yarn fabrics was measured by using a Network Analyzer -EM shielding test (ASTM D4935-99) in the frequency range from 2018,000 MHz.

In this investigation the complex copper core spun yarn (Cotton Sheath and Polyester Sheath) of 179, 118, 98, and 84 tex count of copper core yarns were produced by Dref friction spinning machines and the count of 74 and 59 tex of copper core yarns (cotton sheath and polyester sheath) were produced by ring spinning machines with core attachments device for electromagnetic shielding yarn production purpose. The article reports the effects of the process variables on tensile properties of the copper core yarn as well as individual core and sheath components. Various parameters such as Spinning drum speed, the sliver material, core materials, and count of the yarn were changed to investigate how various parameters affects the tenacity of the complex copper core spun yarn.

Thermal zone was created at the spinning triangle of ring frame to produce 33/67 polyester-/cotton-blended yarns. The tenacity of modified yarn properties was compared with the yarn produced without thermal zone. Furthermore, to study the influence of gauge length in tenacity of these yarns, tests were conducted at various gauge lengths and Weibull plots were also obtained. Fibre failure at various gauge lengths was studied. The reliability analysis showed that the modified treble rove yarns are superior to the normal treble roves feed yarns.

In this work, copper core yarn (cotton sheath) was made into a plain fabric and treated with nanosilver particles. Copper (diameter 0.09 mm) was used as core material for producing Dref II core yarn with resultant count of 295 tex and core/sheath ratio 16/84. The cotton material is used as sheath. The Dref II friction spinning was used to produce the copper core yarn. In order to improve the electromagnetic shielding effectiveness of copper core yarn woven fabrics by nanosilver finishing, the copper core yarn (cotton sheath) was made into a plain fabric and treated by nanosilver particles with various levels of concentration, temperature, and curing time through Box-Behnken design. The electromagnetic shielding effectiveness values for different applying conditions were measured and analyzed, and are discussed in this paper.