The ACTion project, funded under the German grant reference 03INT711AD, aimed to develop large‑scale manufacturing methods for advanced sandwich composites that combine a lightweight, foamed core with stiff, high‑strength face sheets. The research was carried out from 1 January 2020 to 31 December 2022, with a cost‑neutral extension until 30 June 2023 to accommodate pandemic‑related delays. The consortium comprised several industrial and academic partners, with INVENT GmbH taking a leading role in requirement analysis, tooling design, material characterization, and the development of a design tool for functionally integrated sandwich structures.

Technically, the project was structured into seven work packages (WP1–WP7). WP1 established a generic demonstrator concept and defined the production process and material selection for automotive applications. In WP2, a small‑scale laboratory process was set up at the Open Hybrid LabFactory to produce test specimens of foamed thermoplastics. These specimens were used in WP3 for experimental evaluation, where rheological behaviour, mechanical strength, acoustic damping, and thermal conductivity were measured. The data obtained in WP3 fed into the numerical simulations of WP5, which modeled mold filling, foaming dynamics, and the resulting mechanical, thermal, and acoustic properties of the sandwich components. The simulation results were validated against the experimental data from WP2, confirming the fidelity of the models.

WP4 focused on identifying industrial applications beyond the automotive sector, particularly in aerospace where lightweight interior components such as folding tables, seat covers, and drawers are required in high volumes. A specific demonstrator—a drawer for an aircraft trolley—was selected and fabricated using existing tooling from consortium partners. The manufacturing process employed the Ku‑Fizz foaming technique, and the resulting parts were subjected to the same suite of characterisation tests as in WP3.

Environmental and economic aspects were addressed in WP6, where model‑based assessments of the life‑cycle environmental impact and cost of sandwich manufacturing were developed. Automated data analytics and data‑driven process control strategies were also explored, along with a scale‑up model tailored to automotive production scenarios.

Finally, WP7 delivered a design tool that integrates functional requirements—mechanical, thermal, acoustic—into the design of eco‑efficient sandwich composites. This tool allows designers to optimise core density, face‑sheet material, and geometry to meet specific performance targets while minimising weight and material usage.

Throughout the project, INVENT GmbH coordinated the work, supported the requirements analysis (WP1), and implemented the design tool (WP7). It also performed material characterisation (WP3) and explored alternative applications (WP4). Regular teleconferences and project meetings ensured continuous exchange of progress and refinement of objectives. The project’s outcomes include validated numerical models, a proven manufacturing process for foamed thermoplastic sandwich structures, and a functional design tool, all of which lay the groundwork for scalable production of lightweight, multifunctional components in automotive and aerospace markets.