The demand on lighter and more stable structure in aerospace and other sectors has led to substantial progress in two important research-fields. On one hand, fiber-reinforced materials or composite materials are used increasingly in lightweight structures. This kind of material has a high stiffness compared to its weight. On the other hand, additive manufacturing, mostly known as 3D printing, revolutionizes the whole manufacturing industry, allowing the creation of more complex customized structures.
Within the scope of our focus project, we want to merge these two research-fields into one system. The previous processing of composite materials is often very costly limited in construction form and possibilities. 3DCarb offers a fully automated alternative, where cheap untreated material goes through every process step in a really compact volume and comes out completely finished.
Our project starts on an already finished system, which was developed by Martin Eichenhofer, our current supervisor, in several years.
Our goal is to develop an improved process, that is compatible with conventional processes. The quality of the material has to reach the requirements for aerospace applications and the process speed has to increase to make it attractive for industrial use.
To reach our goals, we have to minimize the void content, without losing the high process speed.
The application head completely processes commingled yarn to a finished product that does not need any further treatments. Thereby, the material passes through new and innovative process steps: After a first preheating and preconsolidating step, several yarns are brought together, molten and formed in the pultrusion unit. This allows a local (In-situ) consolidation. Afterward the rod goes through a pulling unit and finally through an extrusion head.
A variothermal extrusion-die at the end of the system enables a highly accurate thermal treatment of the rod. this is why we can reach novel applications, without losing in quality.
Thiese steps keep a low void content, so that our end product can keep up with comparable conventional processes but provide versatile applications at a better cost-efficiency.
Thanks to an industrial robot arm, the application head can be moved more freely in space. Together with the variothermal extrusion-die, this allows us a load tailored designmeaning that we can lay down rods in the load-direction. We can therefore produce lightweight structures that were considered impossible to autonomously process (i.e. curved panes).
We are also able to do complete function integrations, such as integrating cabling and sensors directly during the manufacturing process.