Progressive crush response of hybrid felt/fabric composite structures

The energy absorption response and damage characteristics of composite structures are of increasing interest to both automotive and aerospace areas, as a means of achieving superior crash impact performance and energy absorption as compared to metals. Previous research has concentrated almost entirely on axisymmetric cylindrical tubes, hour-glass shapes and conical frustra. In this paper a multicelled geometry connected by flanges is considered and characteristics of progressive crush as a result of the use of needle-felts in addition to conventional fabrics in the preform are investigated. It is shown that the presence of the needle-felt layer can drastically modify crush response and can serve as a means of energy absorption through hybridization. The results of ten preform types are discussed and compared on the basis of a number of metrics in order to assess viability of both structural response and crash worthiness.