Fracture performance of epoxy foam: Low density to bulk polymer

Strain rate dependent compressive mechanical properties and dynamic failure of pre-strained epoxy syntactic foam

“…This is similar to the increase of density of the pre-strained foam [37]. As reported by Gupta et al [51,52] and Irven et al [53], the density significantly affects the mechanical behaviour of syntactic foam. Assuming that the reduced volume of the bulk foam is solely due to the failed microballons, the estimated volume fraction of the failed microballons decreases to 48 %, 18 % and about 0 % after three levels of pre-strained deformation.…”

“…The comparison of energy absorption illustrates the brittleness of the ESF is gradually suppressed with the pre-strain. The density is an important parameter to describe the mechanical behaviour of syntactic foam, as can be seen in the studies of Gupta et al [51,52] and Irven et al [53]. Here, the specific energy absorption ∫ σdε ρ , which is the strain energy density ( ∫ σdε) divided by the foam density ρ, is compared in Fig.…”

“…By considering the embedded collapsed microballons, this study provides additional information on the variation of fracture strength and the density issue of syntactic foam, as can be seen in the recent works of Carolan et al [21] and Irven et al [53]. From a practical point of view, the evaluation of the crushability of the pre-strained foam would be considered as a means to study the behaviour of the foam under large deformation.…”

Effects of reactive diluent on processing, structure, and properties of epoxy foams and their sandwich composites

“…However, the sample also exhibits the characteristics of ductile fracture. According to the research of Irven et al, 31 it can be inferred that during the fracture process, the crack tends to move forward along the path with the least resistance. The epoxy resin component is capable of withstanding significant stress.…”