The target applications for these ThermHex^WAVY PEI honeycomb cores are mainly aircraft interior components. With a need for ramp up of production volumes and increasing focus on safety, health and environment, efficiently produced thermoplastic honeycombs made with the proven EconCore technology offer great potential. The thermoplastic honeycomb is typically laminated with fiber-reinforced thermoplastic composites, resulting in a monopolymer, all-thermoplastic sandwich solution. 

Patented technology

A key innovation that now allows to bring the PEI honeycomb to aerospace applications is EconCore’s new patented ThermHex^WAVY cell technology. The continuously produced PEI honeycomb with an optimal structured geometry of cell walls that are wavy-shaped brings a drastic increase of the cell wall buckling resistance, under out-of-plane compression and shear loads, the key mechanical properties of honeycomb cores.

At JEC 2025 in Paris, ThermHex Honeycomb and EconCore presented another innovation: ThermHex^COEX honeycomb core profiles. This development is based on the extrusion of thermoplastic polymer polypropylene into a multi-layer flat film followed by a process of thermoforming into honeycomb cores. The structured cellular wall comprises of two solid outer layers and a lower density inner layer.

The innovative three-layer sandwich cell wall resulted in significant improvements in stiffness and mechanical strength under compressive loads, making it particularly advantageous for lightweight construction applications. The foamed inner layer plays a crucial role by contributing to the overall density reduction of the cell wall, thus enabling cell walls with an increased cross-sectional area at a constant weight. This increase in wall thickness results in a simultaneous rise in buckling stiffness, delaying the onset of buckling failure as the primary failure mechanism of honeycomb cores under shear and compressive loads.

The internal cellular structuring was achieved by adding a chemical blowing agent and nucleation to the base granulate of the inner layer. The concept creation and production trials conducted by ThermHex were supported by FEM simulations.