Impact compressive behavior of warp-knitted spacer fabrics for protective applications

This paper presents a study of the impact compressive behavior of warp-knitted spacer fabrics developed for human body protections. A series of warp-knitted spacer fabrics was produced on a double-needle bar Raschel warp knitting machine by varying their structural parameters, including spacer monofilament inclination and fineness, fabric thickness, and surface layer structure. A drop-weight impact tester was used to test these fabrics with predefined impact energy. The impact process of a typical spacer fabric was analyzed based on its impact contact force-displacement curve, energy absorbed-contact force curve and transmitted force-time curve. The effects of the structural parameters on the impact compressive behavior of the warp-knitted spacer fabrics were also discussed. The relationship between the peak transmitted force and peak contact force was established for these fabrics. The study shows that the warp-knitted spacer fabrics can be used as a type of effective material for human body protection due to their high energy absorption capacity and reduction of the contact peak force. The study also shows that all the structural parameters significantly affect the impact compressive behavior of the warp-knitted spacer fabrics in terms of peak contact force, peak transmitted force, and energy absorbed at different impact compressive stages. According to the results obtained, the warp-knitted spacer fabrics studied can reduce about 33.16% of the peak contact force.