3D printing meets fibre compound materials

March 07, 2016 // By CHRISTOPH HAMMERSCHMIDT
Individual design and flexible production methods no longer preclude requirements such as robustness and sturdiness. Products like automotive seat shells or artificial limbs – which need to meet both requirements – can now be made in a combined process of 3D printing and fibre compound technology.

The Fraunhofer Institute for Production Technology (IPT) in Aachen (Germany) is exploring the combination of the abovementioned two technologies within the LightFlex research project. The 3D printing technology ensures a maximum of flexibility with respect to shape and functionality of a component whereas fibre compound guarantees high stability even under high load.

 

However, these benefits are only theoretical ones. Currently combining the two technologies it is considered very difficult. In today’s manufacturing technology, reinforcing injection moulded components through embedded fibre compound materials require expensive and inflexible tooling. Thus, production is possible only in large quantities to be profitable. Specific functionalities or product variants can only be implemented by means of costly, complex rework. For this reasons, the production of small series and, even more so, of  prototypes fails on grounds of too high costs. Fraunhofer IPT along with partners in the LightFlex projects now plan to replace injection moulded components through parts manufactured in a 3D printing process. Additive production, as 3D printing is also called, allows individualising the components almost arbitrarily. And they can be provided with the desired functionality before they are joined together by means of a thermoplastic fibre compound material and thus are getting the desired load-bearing capacity.

 

To optimise the components, the scientists utilise so-called organo sheeting made of unidirectional semi-finished materials for the thermoplastic fibre compound components. Instead of standard products with fixed physical dimensions, the scientists are using custom-cut organo sheetings, that have been manufactured in a production plant installed by Fraunhofer IPT. There, they are made at the desired shapes and dimensions which reduces waste. In addition, the expenditure of energy can be significantly reduced. The plant has been developed in the context of a predecessor project.

 

The organo sheets then are joined with the 3D structure in a thermoforming process. Overall, the project LightFlex covers the entire process chain of a connected, adaptive production, from the production of