We are working on the large-scale printing of parts in thermoplastic materials

5 July 2024
Pieza impresa pellets

“The characteristics of the consumables and equipment make the investment required very attractive compared to other additive technologies”

We have developed a highly automated hybrid cell for the extrusion, machining and dimensional control of parts up to three metres long in thermoplastic materials.

Pellet 3D printing is a relatively new technology in which thermoplastic pellets are extruded layer by layer to generate the desired geometry. Its main advantage is the ability to produce parts with dimensions of several metres, as a heated chamber is not required, and it is possible to reach feed rates of close to 100 kg/h.

The characteristics of the consumables and equipment make the investment required very attractive compared to other additive technologies. Potential applications have already been identified in several sectors that would return significant benefits to manufacturing companies and their customers.

Manufacture of moulds and tooling for the aerospace, wind energy and automotive sectors, as well as components for the shipbuilding and construction sectors.

The cell features automatically interchangeable extrusion heads, machining and 3D inspection and a scalable linear track for larger parts. The operations are controlled by a user-friendly interface that loads and runs programmes carried out off-line and defines the extrusion conditions from a knowledge base embedded in the system, thus guaranteeing safe and competitive input ratios depending on the material under consideration.

The cell environment is virtually replicated, allowing for real-time process monitoring and subsequent analysis of the stored variables.

Knowledge of the process is just as important as the equipment, guaranteeing the productivity of the operation and the quality and properties of the manufactured part in the materials of interest according to the potential applications.

Applications capable of withstanding high temperatures

TECNALIA has focused the development of processes on high-performance materials suitable for engineering applications and capable of withstanding high temperatures.

  • For example, in the case of carbon fibre reinforced polyamide 6 (PA 6 CF20), significant improvements have been achieved in controlling thermal distortions and the generation of internal defects during the extrusion process. The mechanical properties achieved, particularly in the normal direction to the input, are notably superior to the values reported to date.

Currently, we have several demonstrators of potential applications in companies, manufactured with our own equipment and thanks to the knowledge developed.

Much of the development has been carried out within the @MOLDAM (EIT Manufacturing, ref. 23025) project.