Effect of Stitching Parameters on Ballistic Resistance of Kevlar Fabrics

There may be advantages and disadvantages of stitching in soft body armours. The stitching process is often a time consuming and costly step in manufacturing. It is assumed by most armour designers that stitching can create weak points (at the stitched points), and also reduce armour flexibility to users, resulting in comfort issues. This study investigates the relationship between soft body armour stitching parameters with ballistic resistance test results (blunt trauma depth) using the Design of Experiments (DOE) approach. A Response Surface Methodology Design was carried out to identify the factors that influence the ballistic impact resistance of stitched fabric armour. The factors that were studied were stitching perimeter, number of fabric layers and thread strength. The ballistic test was conducted with reference to the NIJ 0101.08 standard. The developed statistical model showed that the number of fabric layers and stitching perimeter have significant influence on ballistic resistance capability as compared to the others factors. This study can be a reference for body armour manufacturers for considering the level of stitching to be applied during the soft body armour production process.

Keywords: Fabric armour; stitched fabric; blunt trauma depth; design of experiment (DOE); Response Surface Methodology Design.

M.M.Noor