فهرست نشریات علمی دسترسی آزاد ایران

Recently, sandwich composites have been in high demand in the air, maritime, and land transportation industries. Particularly, epoxy matrix composites reinforced with carbon fiber have become desirable structural materials due to their high static strength and stiffness characteristics. On the other hand, if Kevlar fibers are used as a substitute for or alongside graphite fibers for reinforcement, the damage tolerance of composite materials may be significantly enhanced. The current research investigated how four composite cylinders constructed of Kevlar and carbon fiber react to low-velocity impact. These cylinders can be classified physically as carbon-only, Kevlar-only, carbon-outside/Kevlar-inside, or Kevlar-inside/carbon-outside. A drop-weight impact device containing a free-falling spherical steel impactor was used to apply the impact to the samples. Abaqus/Explicit software based on finite element modeling (FEM) was employed to assess the impact behavior of specimens. Then, the composite cylinders were modeled as standard shell composite lay-ups, while the impactor was represented as a stiff analytical part. The results demonstrated that carbon fiber was less effective at absorbing energy than Kevlar fiber and that the carbon-only specimen had the strongest contact force and the least deflection compared to the other samples. To further validate the analysis, empirical and numerical findings were carefully compared.