Impact response of 3‐D woven composites reinforced by consolidated rods

Abstract This paper examines the impact response of three‐dimensionally woven fabric composites using consolidated rods in the axial direction. The material processing includes fabrication of the 1‐mm rods by pultrusion, formation of the fabrics, and impregnation of the resin. A weaving setup incorporating the rods in the axial direction has been developed. Using the setup, three types of orthogonal fabrics with varying the tow sizes have been made. The microgeometry of yarns and the distribution of fibers were examined. Impact tests were carried out using an instrumented drop‐weight impactor. Matrix cracks and rod debonding are the principal damage modes on the top and bottom surfaces. However, the crack configurations on these surfaces are very different. Formation of these damage modes and the associated influencing factors have been discussed. One feature not found in conventional composites is rod pull‐in, which is a result of rod debonding and sliding. The pull‐in creates a zone of holes on the specimen edge, revealing how the stress wave propagates from the impact to the non‐impact sides. It is found that the pull‐in is more pronounced near the non‐impact side. The load‐time and energy‐time histories have been examined and related to how the specimens respond to the impact.