Damage Prediction of Quasi-Isotropic Carbon/Epoxy Composite Panels Impacted by High Velocity Ice

摘要

Aircraft structures made from polymer-matrix composites are exposed to high velocity impact from hail ice. These impacts can create damage, including internal delamination, that is not visually detectable and is thus of great concern from a safety standpoint. The focus of this paper is on the prediction of delamination damage in toughened carbon/epoxy tape laminates due to high velocity simulated hail ice (SHI) impact. Experiments and analytical work have been completed on a series of composite panels to determine the failure threshold energy (FTE), the contact force, and the prediction of the onset of delamination damage which can be associated with a critical force level. The damage is predicted through the use of finite element analysis (FEA) employing cohesive elements. Since the contact force of ice impact onto a flexible panel is not experimentally measureable, the force history was determined via FEA. While thicker panels correspond to higher critical forces, the critical force was found to be independent of SHI diameter.