The fly ash (FA) particulates are used in this study to reinforce the polyurethane foam (PUF) core. The FA particles inclusion improves the mechanical performance of the PUF core under compression by increasing its modulus of elasticity. Low-velocity impacts have damage dynamics that are pretty similar to quasi-static indentation. Consequently, the indentation resistance capability of the PUF core is investigated for three types of indenter nose tips with varied FA wt. Percentages (flat-circular, hemispherical, and conical). The results reveal that the reinforced foam core’s resistance varies with reinforcement percentage under indentation. However, FA reinforcement to PUF does not necessarily improve indentation resistance. The damage mechanism of the PUF core under indentation has been evaluated for each type of indenter. The interaction of crushing, shear, and tear of the damaged surface with the change in indenter nose tip has been explained with 0–20% variation of FA particles. Scanning electron microscope (SEM) images are taken for the analysis of the damaged PUF core cross-section at the indented location. Earlier mechanical findings of the scatter in deformation behavior with the indenter nose tip geometry are substantiated by the SEM studies.
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