by Karsten Braun, Scientist, Fraunhofer Institute for laser technology ILT
Despite their great potential for individualization, 3D-printing processes for polymer parts like SLS (Selective Laser Sintering) and FDM (Fused Deposition Modeling) have the particular disadvantage of a high surface roughness; therefore, surface finishing is often necessary. However, current finishing procedures often have deficits such as low flexibility, long process times or incorporation of abrasives in the component. Therefore, Fraunhofer ILT is developing a non-contact, laser-based polishing process for additively manufactured plastic components.
In this presentation process basics of laser polishing including a special process strategy called “quasi-top-hat scanning strategy” that is especially suited for plastics will be explained and recent achievements on 3D-printed polymer parts will be presented. Example materials are Polyamide, PEEK or TPU and example roughness values after laser polishing are between Sa = 0.1 µm and Sa = 1 µm. It will also be discussed where laser polishing might be applicable as an ancillary post process in the future.
What drives you?
Scientific work in general is always interesting. You learn new things every day. Also seeing a process being developed from a very basic stand to an actual application is a huge motivator.
Why should the delegate attend your presentation?
Laser polishing is not yet known very well in the AM industry. Although it is a very new approach to polish 3D printed polymer parts, it has great potential due to its contactless, digital and fully automatable process principle. The presentation will give an introduction in the laser polishing process and an overview about recent achievements. Also it will show where the process is applicable already and where potential future applications might be.
What emerging technologies/trends do you see as having the greatest potential in the short and long run?
The laser polishing is surely a promising technology in the long run but still needs much development work.
Despite that combinations of different technology will probably become the most efficient ways to produce the best results in terms of quality and process speed, especially in the post processing.
What kind of impact do you expect them to have?
The laser polishing will probably fill the gap between fast post processes with medium quality and high quality post processes that are slow and expensive.
What are the barriers that might stand in the way?
The laser polishing still needs much development work. To get a good process it has to be invested into the development.
The technology of tomorrow has to be developed today.
About Karsten Braun
- Name: Karsten Braun, 28 years old
- Studied physics at the RWTH Aachen University in Germany
- Master thesis was written at the Fraunhofer ILT in the field of laser based optics manufacturing
- Since 2016: Scientist at the Fraunhofer ILT and working on the laser polishing of glass and plastics
With more than 540 employees and more than 19,500 m² net floor space the Fraunhofer Institute for Laser Technology ILT is worldwide one of the most important development and contract research institutes of its specific field. The activities cover a wide range of areas such as the development of new laser beam sources and components, precise laser based metrology, testing technology and industrial laser processes. This includes laser cutting, caving, drilling, welding and soldering as well as surface treatment, micro processing and additive manufacturing.
The Fraunhofer ILT is part of the Fraunhofer-Gesellschaft, with 72 institutes, more than 26,600 employees and an annual research budget of 2.6 billion euros.