Advanced composite materials like carbon-fiber-reinforced-polymer (CFRP) laminates are now widely used in the aerospace
industry due to their outstanding high strength-to-weight ratio and very good rigidity. However, composite structures
are prone to impact damage, which can occur either during the processing stages or during inservice operations. This paper
presents the impact behavior and damage characteristics of CFRP panels at low velocity impact tests over a range of impact
energies. An environmental aging machine and a tensile fatigue method were used to simulate the inservice environmental
aging effects. Cross-section images of impact defect structures from multiple directions were demonstrated and discussed by
utilizing ultrasonic nondestructive evaluation (NDE) method.
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