Development of Bi-Stretch Auxetic Woven Fabrics Based on Re-Entrant Hexagonal Geometry

This paper reports a development of bi-stretch auxetic woven fabrics by using non-auxetic yarns and weaving technology. The fabric structure is first designed based on a re-entrant hexagonal geometry by combination of loose weave and tight weave in a woven fabric structure, and then fabricated on a rapier weaving machine by using both non-elastic and elastic yarns. Two variations of the fabric are produced by using different elastic yarn arrangement in weft direction. The designed auxetic geometry is finally achieved after a washing process due to creation of non-uniform contraction or shrinkage profiles within the fabric structural unit cell. The testing results showed that the developed fabrics exhibit negative Poisson ratio effect in both weft and warp directions in a large range of tensile strain.