FAILURE BEHAVIOR OF WOVEN FABRIC COMPOSITES

Woven fabrics are now considered important reinforcing materials for use as unidirectional (UD) tapes in composites technology. The understanding of the failure mechanisms in woven fabric composites, however, is not complete. The tensile behavior of on-axis and off-axis specimens of E-glass/epoxy and carbon/epoxy plain weave fabric composites with and without a hole is studied. The failure behavior of woven fabric composites differs from UD tape composites. Because of the interlaced nature of warp and weft fibers, their reorientation along the loading direction is possible in off-axis specimens. The reorientation of fibers may increase the notched strength over the unnotched strength. The failure modes in angle-ply laminates of UD tape are mostly matrix cracking, fiber pullout, delamination, and to some extent, fiber breakage, whereas in woven fabric composites, the ultimate failure is always due to fiber breakage which, in general, is a preferred failure mode