Effects of Impact Damage on the Energy Absorption Capabilities of Composite Materials

Abstract

In the current investigation, the effects of in-service impact damage on the energy absorption capabilities, and damage evolution of two different geometries, corrugated beams, and c-channel stanchions, have been presented. Both the energy absorber geometries were manufactured using two composite material systems, Hexcel IM7/8552 and Hexcel AS4 PW/8552. Two different stacking sequences evaluated were: [90o/0o]2S and [45o/90o/-45o/0o]s. The pristine specimens were secured in a nonstandard fixture and impacted at the center using a drop tower [1]. The specimens were impacted at different energy levels to introduce varying levels of damage. Postdamage introduction, compression tests were performed at 1 in/s using a high-speed servo-hydraulic test frame. All the tests were supported with high-speed Digital Image Correlation (DIC) to obtain damage evolution and surface strains. A comparison of the energy absorption capabilities and damage modes between the pristine specimens and specimens with impact damage has been reported.