Scalability of composite metastructures

Project team

• Victor Gaultier, Doctoral Student
• Georgios Pappas, Senior Scientist
• Paolo Ermanni, Principal Investigator

Contact

• Victor Gaultier

Project duration

•  September 2021 to present

Funding source

• SNSF grant no. 200021-​192082; Variable Stiffness Composite Metamaterials
• CMASLab internal funding

Project description

This research project deals with the field of composite metamaterial inspired structures, defined as metastructures. The prefix "meta" refers to "after" or "further" and indicates evolution or transformation. In the case of meta-material inspired structures, from now on defined as metastructures, the prefix "meta" indicates that the considered structure possesses properties that are not visible in nature, governed by their macroscopic characteristics instead of their constituent material's characteristics. Those are geometry, topology, orientation, size, etc.

The complex geometry of metastructures currently requires the versatility of additive manufacturing, but possess a low durability. This limits their potential for actual full size engineering applications.

For the development of durable thin-ply reinforced metastructures, thermoplastics matrix systems appear to have great potential. Furthermore, thermoplastic composites can be re-melted upon application of heat, which paves the way for the welding and reshaping processes, which enhance the design freedom. On the other hand, higher processing temperatures and pressures are required for the manufacturing process of thermoplastic reinforced composites. In this sense, the use of regular tooling and autoclave processing is not possible. This limitation is therefore a challenge for the manufacturing of thermoplastic-based metastructures.

Thin-ply composites reduce the risk for matrix cracking and delamination. Furthermore, thin-plies allow for thin-shell laminates, which tolerate high bending curvature and thus, and thus, low bending radii.

To allow the scalability of metastructures, research on manufacturability and durability are needed. Filling this research gap would allow the development of metastructures in the fields of shape adaptation, multi-stability, lightweight load-carrying structures, or the control of non-structural properties.