Energy absorption in glass-reinforced continuous strand mat composites

A unique test fixture was developed for determining the energy-absorbing mechanisms in automotive composite material systems. The objective of the test method was to quantify the energy absorption and identify the failure mechanisms associated with the observed frond formation in progressive crush testing of composite tubes by testing less costly composite plates under progressive crush load conditions. Quasi-static progressive crush tests were performed on glass/polyurethane continuous strand mat (CSM) composite plate specimens. The effect of various test parameters on energy absorption was evaluated by varying the following parameters during testing: the loading rate, profile radius, and profile constraint condition. The experimental data in conjunction with the test observations were used to develop analytical models for predicting the crash-worthiness of automotive composite structures. The crushing process and the load-deflection curves were similar to the progressive crushing of tubes. Modification of the basic specimen geometry was required when testing material systems that have low axial stiffness to prevent a global buckling mode. (C) 2003 Wiley Periodicals, Inc.