Failure of Composites with Discontinuous Fabric Preform under Bending

Abstract

During the fabric preform and/or mold closure processes of the resin transfer molded composites (RTMCs), the discontinuous fabric patterns such as wrinkling and overlapping can be occurred and influenced the failure strength. It is found that the composites with discontinuous fabric preform had two failure mechanisms as functions of fabric ply number and discontinuous fabric length under the three-point bending. First, the failure modes can be related to the bend strengths that were controlled by the interfacial bonding strength depending on the discontinuous fabric length. Second, the failures were controlled by the potential strength of fabric when the discontinuous length reached the critical value. Moreover, the experimentally measured results of the normal and discontinuous preform models under bending were compared to examine the safety conditions as functions of fiber content and other factors.