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

Abstract

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.

Single‐ and Double‐Layered Bistretch Auxetic Woven Fabrics Made of Nonauxetic Yarns Based on Foldable Geometries

“…These properties include shear modulus, energy absorbance, vibration damping, [5][6][7][8][9] sound absorption, [10] indentation resistance, [11][12][13] and synclastic behavior for better formability. [14] The known naturally and manmade auxetic materials include metals, [15] laminates, [16] gels, [17] crystalline structures, [18][19][20] polymers, [21,22] composites, [6,8,23] foams, [1,24] and textile materials including fibers, [22,25] yarns, [26][27][28][29][30] and fabrics including woven fabrics, [26,27,[31][32][33][34][35][36][37] weft-knitted fabrics, [38][39][40][41][42][43] warp-knitted fabrics, [44][45][46]…”

“…[1,3] Structural modification is one of the various mechanisms leading to auxetic effect. [18,19,31,33,42] Therefore, a simple molecular design approach is based on producing the auxetic materials by modifying the macrostructure of the material. [4,22] One such example is materials which possess hinge-like features, and they can extend in longitudinal as well as in transverse direction when a tensile force is applied.…”

“…[4,22] One such example is materials which possess hinge-like features, and they can extend in longitudinal as well as in transverse direction when a tensile force is applied. [31,33,42] Moreover, there are many mechanisms which can be achieved by structural modification and lead to auxetic behavior. Tan et al proposed an auxetic nonporous smooth curve sheet.…”

“…[55] Similarly, it is proposed that the structural modification can lead to crystal structures exhibiting auxetic behavior. [56,57] Among auxetic textile materials, auxetic woven fabrics produced by applying the technique of structural modification and made of nonauxetic yarns [31][32][33][34][35] have gained extraordinary interest of researchers in modern times. The conventional woven fabrics have a positive PR which means that they undergo contraction in transverse direction upon stretch in the longitude direction.…”

Auxetics and Other Systems of Anomalous Characteristics

“…Staying within the auxetic textiles theme, but this time considering auxetic fabrics rather than auxetic yarns, A. Zulifqar and H. Hu [12] report in 'Development of bi-stretch auxetic woven fabrics based on re-entrant hexagonal geometry' the development of bi-stretch woven auxetic fabrics displaying auxetic response. The fabrics display the re-entrant hexagon motif for auxetic behaviour and are made using an established weaving machine and non-auxetic yarns.…”