Effect of multiphase fiber system and stacking sequence on low-velocity impact and residual tensile behavior of glass/epoxy composite laminates

This article investigates the effect of multiphase fiber system based on plain weave woven fabrics and chopped short fibers in glass/epoxy composite laminates on low-velocity drop weight impact and quasi-static tensile after impact (TAI) behaviors. In this regard, glass/epoxy composites with two stacking sequences (intercalated and sandwich-like lay-ups) were tested and compared with homogeneous standard composites fabricated with either only woven or only chopped fibers. In all the samples with multiphase fiber system, the amount of woven and chopped glass fibers were equal (4 layers and 3 layers, respectively), while stacking sequences were different. This enabled us to investigate the associated influences of fiber architecture and stacking sequence on low-velocity drop weight impact and TAI behavior of the glass/epoxy composite laminates. All the glass/epoxy samples were impacted at four various impact energy levels, particularly 2, 4, 6, and 8 J. Results depicted that fiber architecture and stacking sequence played a vital role in low-velocity drop weight impact and TAI behavior (i.e., damage degree, absorbed energy, peak contact force, residual deformation, residual tensile strength, displacement to ultimate failure, and failure profile) of the glass/epoxy samples. The results depicted that the sandwich-like lay-up configuration presented superior impact properties and damage tolerance capabilities at low impact energies (up to 4 J). On the contrary, intercalated lay-up arrangement suited better to withstand widespread damage generated by higher impact energy levels (6 and 8 J), because they enabled a more efficient redistribution of low-velocity impact damage in the composite. POLYM. COMPOS., 40:1450-1462, 2019. (c) 2018 Society of Plastics Engineers