MOBILITY ENGINEERING Produced by SAE Media Group
MOBILITY ENGINEERING
Magazines
Magazine cover

Current Issue

Archives

Magazine cover

Current Issue

Archives

Magazine cover

Current Issue

Archives

Magazine cover

Current Issue

Archives

Testing Silver-Coated Nylon Fibers as Electrical Conductors

Electro-textiles for connecting electronic devices might eventually be embedded in clothing.

Tests have been performed in an effort to gain understanding of electrical and mechanical properties of silver-coated nylon fibers subjected to stresses and strains and exposed to various environmental conditions. This effort is part of a larger effort to develop electro-textiles ("e-textiles") [electrically conductive textiles] that could be incorporated into future Army combat uniforms and used therein to couple electrical power and signals between electronic devices. Understanding of the effects of stresses, strains, and environmental conditions is important because of a need to ensure adequate performance of e-textiles under the widely varying, harsh conditions to which military uniforms are exposed when worn in extreme climates, during laundering, and during storage at high temperatures.

The Fractional Change in Electrical Resistance of a silver-coated nylon fiber was determined from measurements of electrical resistance immediately after application of tensile strain.
The nylon fibers included single filaments and 34-continuous- filament yarns. Before the tests, the fibers were coated with thin layers of silver by electroless deposition. The tests included standard measurements of stress versus strain, strength, and elongation to break in a tensile testing machine, and measurements of electrical resistance in the presence of tensile stress and strain and in post-strain and post-damage conditions. Electrical resistances were also measured after immersion in aqueous solutions of various degrees of acidity and alkalinity, after exposure to high temperatures, and after thermal cycling. Morphological examinations of the silver coats on the fibers were performed by means of scanning electron mi cros - copy.

The conclusions drawn from the measurement data acquired in the tests include the following:

  • As expected, electrical resistances of fibers increased with applied strains (see figure). In general, the piezoresistant behavior of a fiber of the type tested depends on the mechanical behavior of the base fiber as well as on the microstructure of the silver coat: changes in electrical resistance can be attributed to both changes in dimensions and changes in separation of silver particles.
  • Following removal of applied strains, fibers recovered mechanically and their electrical conductivities were almost completely restored. However, the response times (times for viscoelastic recovery and concomitant recovery of electrical conductivity) were found to be so long — of the order of minutes or longer — that one could not rely on such recovery in practical applications.
  • Electrical conductivities of fibers after thermal cycling and after exposure to high temperature were not diminished.
  • Although fibers in clothing are not normally subjected to large induced strains, any such strains and the associated changes in electrical resistance are of concern with respect to reliability of electrical connections. A plausible solution to the reliability problem may lie in the design of novel yarns or fabric structures to eliminate most or all induced strains.

This work was done by Suzanne Bosselman of the U. S. Army Natick Soldier Research, Development and Engineering Center.

ARL-0043

Topics:
Coatings, colorants and finishes Coatings, colorants, and finishes Conductivity Electric power Emissions Exhaust emissions Fabrics Fibers Materials Materials properties Off-board energy sources Particulate matter (PM) Reaction and response times Tensile strength Test procedures Textiles
This Brief includes a Technical Support Package (TSP).
Document cover
Testing Silver-Coated Nylon Fibers as Electrical Conductors

(reference ARL-0043) is currently available for download from the TSP library.

Don't have an account?

More From SAE Media Group

    Magazine cover
    Defense Tech Briefs Magazine

    This article first appeared in the August, 2008 issue of Defense Tech Briefs Magazine (Vol. 2 No. 4).

    Read more articles from the archives here.

    Overview

    The document titled "Electrical and Mechanical Behavior of Silver-Coated Polymeric Fibers" is a technical report authored by Suzanne Bosselman, published by the U.S. Army Natick Soldier Research, Development and Engineering Center. The report details research conducted from November 2005 to November 2006, focusing on the properties of electrically conductive, silver-coated nylon fibers.

    The primary objective of the study was to investigate the relationship between the fiber composition and morphology, tensile behavior, and electrical resistance, both in strained and post-strained states. The research also examined how environmental factors, such as immersion in aqueous solutions of varying pH levels and exposure to elevated temperatures and thermal cycling, affect the electrical resistance of these fibers.

    The fibers studied were continuous filament yarns made from 100 denier base nylon fiber, consisting of 34 filaments, sourced from Saquoit Industries in Scranton, Pennsylvania. The report is part of a broader research initiative aimed at understanding the fundamental electrical and mechanical properties of conductive textile materials, particularly for applications in e-textiles.

    The document is structured into several sections, including an introduction, background information, experimental approach, results, and conclusions. Key areas of focus include the structure and morphology of the fibers, their mechanical properties, and their electrical properties under various loading conditions. The report also discusses the durability of the fibers when exposed to different pH levels and the effects of thermal exposure and cycling.

    The findings indicate that the silver coating significantly influences the electrical conductivity and mechanical strength of the nylon fibers. The study highlights the potential of these materials for use in advanced textile applications, particularly in military and protective gear, where both electrical conductivity and mechanical durability are critical.

    The report concludes with a summary of the results and their implications for future research and development in the field of conductive textiles. It emphasizes the importance of understanding the interplay between material properties and environmental factors to optimize the performance of e-textiles in practical applications.

    Overall, this technical report provides valuable insights into the behavior of silver-coated nylon fibers, contributing to the advancement of smart textiles and their applications in various fields.

    Top Stories

    INSIDERDesign

    Feature Image Venus Aerospace’s Rotating Detonation Rocket Engine Completes First Flight...

    INSIDERDesign

    Feature Image Bombardier is Digitally Upgrading its Aircraft Design, Engineering and...

    INSIDERDefense

    Feature Image How the US Army is Advancing Research in Robotics, AI and Autonomy

    INSIDERManned Systems

    Feature Image New Copper Alloy Could Provide Breakthrough in Durability for Military Systems

    Original EquipmentManned Systems

    Feature Image ACT Expo 2025: Heavy-Duty EVs, H2 Trucks and Tariff Talk Dominate Day One

    Technology ReportPower

    Feature Image ICE and Hybrid-Electric Propulsion Show Staying Power

    Webcasts