Effect of fiber architecture on the residual strength of laminate glass fiber-reinforced polymer composites after impact

Glass fiber-reinforced polymer (GFRP) composites are widely applied in automotive and shipbuilding industry. However, impact damage is unavoidable to the composites during production or service, and the evaluation of performance degradation after impact is necessary. The architecture of the fiber preform shows significant influence on the impact damage behavior of GFRP. The present work focused on the influence of preform structure on damage evolution and residual load-bearing capability of the composites. The microstructure and the residual strength after the impact of GFRP with plain-weave preform structure and cross-ply preform structure have been investigated, respectively. The low velocity impact primarily caused matrix cracking and delamination, but unobvious fiber failure to GFRP. More impact-damaged plies were detected in cross-ply composites than plain-weave composites after impact. It indicated that plain-weave preform structure owes better impact damage shielding capability. However, the GFRP with plain-weave preform structure exhibited better impact resistant ability under low impact energy but less residual strength under high impact energy, compared with the GFRP with cross-ply preform structure. The interaction between the warp and weft fibers made the plain-weave composites absorbing more energy in a single ply, which was the reason for the plain-weave composites to exhibit excellent damage shielding performance but poor residual strength under high impact energy.