The energy dissipative mechanisms of particle-fiber interactions in a textile composite

Nanoindentation and nanoscratch tests made on the surface of Kevlar KM2 fibers impart contact geometries similar to a typical contact between a particle and a fiber in a particle-infused fabric. In this study, the forces required for indentation and scratching are used as a measure of a single particle gouge of the surface of a Kevlar fiber. The gouging forces and a geometric model are used to calculate the apparent friction and energy associated with particle gouging during impact. The friction associated with particle gouging can be increased up to approximate to 240% compared to Kevlar yarn-yarn friction levels. The energy of gouging a distribution of particles is on the order of 10% of the energy required for axial tensile failure and 25% of the energy required for transverse compression of the fiber (for a limiting transverse strain of approximate to 0.3). The relative contributions of the friction and energy associated with particle gouging to the overall energy dissipated by a textile composite are discussed.