Mechanical Behavior in Compression-after-Impact(CAI) Tests of Conventional CF/Epoxy Laminates.

Extensive experimental research was conducted to pursue mechanical behavior occurred in the actual Compression-after-Impact (CAI) tests for conventional (brittle) CF/Epoxy composite plates. Two test methods, SACMA and NASA were used and examined for future possible improvements. Comparison of experimental results obtained by the two methods is another key issue in the present paper. Focuses are placed on the pursuit of mechanism of behavior during the tests. By examining the mechanics, an appropriate parameter was discovered for unified data reduction obtained by the two methods. It is based on a ratio of a virtual cylinder with an effective diameter of delamination excluding the “brim” region to a total sectional area of the specimen. CAI strengths and initial local buckling in delaminated area were universally explained by this parameter.