Impact Penetration of Sandwich Panels at Different Velocities – An Experimental Parameter Study: Part II – Interpretation of Results and Modeling

Based on sandwich panel penetration experiments and the observed damage patterns, as described in Part I of this article, the individual energy contributions are estimated from simple physical models. It is shown that the most important contributions are from membrane-state fiber stretching, core compression, and friction between core material and impactor. Lesser contributions are from delaminations, core fracture, and debonding between core and back face-sheet. Addition of the energy absorption contributions generally give smaller total absorption than measured; the most likely reasons for this discrepancy are outlined in the conclusion.