Strain sensing behavior of textile structures made of stainless steel continuous filament yarns under uni-axial tensile loading

The objective of this research was to determine the sensing behavior of various textile structures made of stainless steel continuous filament yarns for their potential measurement applications for large strain under high temperature. Four knitting structures are designed and tested. It is observed that the resistance change of the fabrics depends on the structure, the shift of the loop decreasing and the change of the contact resistance between yarns increasing are help to the repeat and sensitivity of the relative resistance change respectively. The relative resistance change also depends on the loading condition, such as strain rate, the maximum cycle strain and temperature. In our four knitting structures, single warp-knit has better repetition in strain sensing than the other three structures, this is because the loops in single warp-knit possess a stabilized behavior, and the plastic deformation is the smallest. The mechanisms of this strain sensing behavior have been investigated including the relationships between electrical resistance of yarn and yarn tensile strain, between yarn length transfer in the strain fabric and the fabric tensile strain, as well as contact resistance of the looped yarns. The major contributor has been deduced to be the change of contact resistance between looped yarns during the deformation.