Modelling of the Indentation Behaviour of Thermoplastic Honeycomb Sandwich Panels

Thermoplastic honeycombs based on polypropylene are one of the latest types of cores used in sandwich structures. Up to now there have been few experimental and modelling studies on the mechanical behaviour of sandwich structures with thermoplastic cores. In this paper, by considering the similar properties of foams and thermoplastic honeycombs, attempts are made to model the static indentation behaviour of honeycombs based on a crushable foam material model using the ABAQUS finite element programme. Comparison of the experimental results and numerical predictions for indentation values show a good correlation up to 20% depth of the panel thickness. It must be noted that in static indentations it would be irrelevant to study the rupture of the skins or cores and, therefore, the crushable foam model should be suitable for modelling the behaviour of thermoplastic honeycombs.