The University of Applied Sciences and Arts of Southern Switzerland (SUPSI) is one of nine universities of Applied Science recognised by the Swiss Confederation. Situated on the border of Switzerland and Italy, the university works closely with a number of full-time researchers and scientific collaborators.
The ICIMSI Research Institute at SUPSI has traditionally used polymeric foams as templates for its cellular ceramics replica process (the deposition of a layer of a slurry - polymer, binder, solvent - onto the template) which are typically produced by gasses evolving during polymerisation.
The labour involved added to the production time and the process resulted in random structures that the Institute could not engineer. This, along with a bid to support its mechanical design activities, led the university to explore the capabilities of 3D printing technology and, subsequently, the installation of a Stratasys Objet Eden260V 3D printer.
Since introducing this equipment, which is capable of printing ultrafine 16 micron layers with exceptional detail, complex geometries and very thin walls, SUPSI has been able to 3D print lattices that can be converted into cellular ceramics via the replica process.
This has dramatically changed the university’s research method of engineering cellular ceramics and, in particular, has seen the university expand its research into thermal protection systems (TPS) for re-entry vehicles. ICIMSI's Professor Alberto Ortona takes up the story:
“3D printing technology has become an integral part of our research into thermal protection systems. We have been developing prototypes that protect the interiors of space vehicles exposed to extreme thermal temperature when re-entering the atmosphere.
“After discovering the Objet Eden260V’s capability to 3D print highly precise, complex structures, I developed the idea of producing complex templates for heat exchangers in three main industries – energy conversion, aerospace and chemical.
"The technology allows us to produce structures required for the final cellular ceramic with a smooth surface and in high detail. This was previously impossible.”
Aided by 3D printing, the department is developing and printing multilayer sandwich structures used in TPS. These structures possess multi-functional properties including insulation, durability and damage tolerance once processed.
This stage is undertaken at the premises of Erbicol SA, the project’s research partner, who covers the structure with slurry. The structure is then turned into ceramic using thermal treatment - a process also known as direct replica.
Since introducing the Objet Eden 260V, the university has also been able to 3D print high-precision, customised cellular ceramic templates for a number of other scientific fields. This includes energy conversion, where the templates are used for porous burners and volumetric solar absorbers, and the chemical industry where catalytic conversions and hydrogen production is tested. Professor Ortona again:
“The Stratasys 3D printing technology has enabled a number of possibilities and ultimately helped us expand our research further, exploring new projects we never thought possible, including development of thermal protectors of re-entry vehicles. In fact, we have seen our third-party research increase by a third as a result of our investment.”
According to Professor Ortona, third-party, scientific research partners such as companies involved in the European research project SMARTEES and THOR have been amazed by the parts performance achieved with 3D printing.
“Our partners have given us fantastic feedback when we have provided them a 3D printed part. There is a great deal of enthusiasm about how they can specialise products for various applications,” Professor Orton concludes.