Tensile response of tubular braids with an elastic core

Circular braiding has been traditionally used for forming tubular structures but there is an ever-increasing interest to use these structures for various composite applications. A tubular braid without any core undergoes large lateral contraction but when elastic materials are inserted in the hollow braids, they can potentially act as reinforcement in energy absorbing composites. In this paper, the tensile behaviour of tubular braids consisting of an elastic core has been predicted based on defined braid geometry, core properties and tensile properties of helically undulated strands of filaments. The constituent filaments considered here are monofilament type but the proposed tensile model of braid–core system has also been extended for low twist multifilament yarns with non-hybrid weave. Braid angle is found to be the most important design parameter for varying the extensibility of braid–core systems. A comparison has been made between the theoretical and experimental stress–strain curves of tubular braids consisting of elastic core.