Technical Coatings in Additive Manufacturing
The surface of additive manufacturing (AM) components is generally coarse and porous, requiring time-consuming and costly post processing. Technical coatings are opening up new possibilities for the AM market, specifically in industrial production.
Encompassing a range of different technologies, additive manufacturing (AM) describes the layer-by-layer construction of an object using a 3D model. 3D printing is arguably the best known of these technologies. Industry can benefit from AM due to its on-demand, low-volume, custom production capabilities. However, the resulting coarseness and porosity of the component's surface pose a challenge: in response to this, Belgian non-profit organisation Sirris and the Fraunhofer Institute for Applied Polymer Research IAP have joined forces to investigate technical coatings in AM.
Smooth, sealed surfaces
Using technical coatings, researchers from both organisations were able to significantly improve the surface properties of AM-produced components. Combining lacquering and polishing has proven to be the most effective method of optimising the surface. "If we only polish our finished components, it takes a long time, and especially with fine, detailed features, we change their shape. It comes to abrasion, which we want to avoid. With the Fraunhofer IAP, we have developed possibilities to overcome the current problems, especially the porous and rough surface, in additive manufacturing," explains Patrick Cosemans from Sirris Flanders.
In addition, components can be further modified for specific functions (functionalised) by using special lacquers or surface treatments. In the current project, the scientists metallised the component to emphasise functionalisation. An alternative functionalisation includes improved scratch resistance or anti-microbial properties. The research project successfully demonstrated that the entire component can be fully functionalised with the appropriate surface treatment.
AM market development
The use of established technologies in technical coatings is opening up new possibilities for the AM market. "In future, the corresponding surface treatment will be integrated into the AM manufacturing process," predicts Dr. Andreas Holländer, expert in surface technology at the Fraunhofer IAP. AM combined with established technologies offers better value and more potential applications than AM alone.