Analysis of the Impact Properties of Structural Foams

Abstract

Several efforts have been made to predict the mechanical properties of structural foams, mainly under tensile and flexural loading modes. The prediction of the mechanical behavior of foams subjected to impact loads remains, however, an unfulfilled challenge. Several investigations have studied the variation of impact properties of structural foams. Both the studied materials, the testing methods employed and the techniques used for sample preparation, vary broadly. Some studies regarding the relation between density and energy absorption capabilities have been conclusive. The influence of cell size and skin thickness have also been analyzed. So far, results show that the foam structure adds a number of complexities to the limited characterization capabilities of conventional impact methods. This study aims to contribute to the understanding of the failure behavior of structural foams. The influence of three different factors will be addressed: the type of imposed loading, through variations in the test method used; the nature of the studied base material (semicrystalline vs. amorphous), and the influence of the foam morphology.

Keywords

Injection-molded foams structural foams mechanical properties impact properties foam morphology skin thickness foam density microcellular.

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