Indentation recovery of shape memory foams produced by solid state foaming

In this study, solid state foaming was used to produce epoxy foam samples with shape memory properties. Foams were indented at room and high temperature by using flat pins with diameter from 1 to 5 mm. Micro-indentations were performed as well only at room temperature. The indentation marks were measured before and after thermal recovery to evaluate the ability of the material to reach the initial shape. For a better understanding of the overall process, a study was made also to predict the initial precursor density as a function of the compaction parameters. This way, it was also evaluated that the effect of the compaction process is covered by the effect of the foaming step