چكيده به لاتين
In laminated composites, the susceptibility to damage from low-velocity impact events (e.g., accidental damage incurred during routine maintenance) is a significant concern. When subjected to impact loading, a composite structure is degraded through various failure mechanisms involving the interaction of matrix cracking, fiber pullout/breakage and delamination. Even with barely visible impact damage (BVID), strength can be significantly reduced. According to researches, the most considerable reduction is that of the compression strength. So damage tolerance is an essential factor in the design of aeronautic and aerospace components made of laminated materials. The literature shows that adding low concentrations of nanoparticles into polymers is an excellent solution to improve their mechanical performances without compromising density, toughness, or manufacturing process.
In this research, the influence of nanoclay on the impact damage resistance of carbon fiber–epoxy composites has been investigated using the low-velocity impact and compression after impact tests. To obtain the optimal percentage of nanoclay, the effect of nanoclay on the mechanical properties of epoxy was first investigated. Epoxy was filled with three different loads of 0.2, 0.4, and 0.8 wt% of nanoclay. For better dispersion and interface adhesion matrix/clay, Epoxy/nanoclay composites were prepared via solution blending technique. A tensile property test was conducted to examine the mechanical properties of the samples with different nanoclay content. It was found that the tensile strength of a composite with 0.2 wt.% of nanoclay increased up to 17.40%, as compared with a pristine sample. Then, Laminated composites containing 0.2 wt% nanoclay were prepared by the vacuum infusion process. The impact performance is analyzed by low-velocity impact tests carried out at different incident impact energy levels (10J, 15J, and 20J). The maximum load of nanoclay filled composite was around 23.1% higher than occurred for control material. Finally, The damage tolerance of laminates is examined by compression after impact test. By adding 0.2% nanoclay, residual compressive strength was improved by 20.03% compared to the neat epoxy laminates.
