Impact Response and Damage of Composite Shell with Various Curvatures

Abstract

In this study, the impact responses and damage behaviors of CF/Epoxy(Carbon Fiber/Epoxy Resin) composite laminates have been studied considering the effects of various curvature radius. During the impact, the impactor's kinetic energy is consumed by the rebound energy of the impactor, strain energy and damage energy. Most of the kinetic energy is consumed by delamination propagation including crack growth. Therefore the contact force-time and deflection-time histories were measured to determine the specimen response. All specimens were visually evaluated for damage after testing, and the non-destructive method(C-scan method) was used to determine the damage area. A device previously developed for impact testing of composite structures was used as the vertical free-falling testing machine. By experimenting with composite structures, we found that substantial differences in the responses of laminates subjected to either flat-plate or shell to transverse loading. And contact force, damage area and absorbed energy of the composite shells were a function of the curvature radius and impact energy.

Impact response of sandwich beams with various curvatures and debonds

“…Results indicated that the contact force increases and the amplitude of shell response decreases with decrease in shell radius. Similar results were observed in the studies of Leylek et al [12] and Kim and Yang [13] and confirmed with the nonlinear finite element analysis. Moody et al [15] experimentally studied the effects of specimen width and curvature on the residual compression strength of composite sandwich panels after low energy impact.…”

“…These papers show that the majority of published work has focused on impact of plates rather than curved structures. The detailed studies on the curved composite laminates have been seen after the 1990s [4–15]. Ambur and Starnes [9] showed that the plate radius and plate thickness were important structural parameters that influence the nonlinear response of a plate for a given impact energy.…”