3D printed components usually require post-processing. Researchers from Fraunhofer IPA and MST Microstrahltechnik Vertriebs GmbH developed a semi-automated test setup in which they examined the effect of different blasting media on components made of different materials.
Want to quickly print out complicated shaped components? 3D printing makes it possible. However, as far as the visible surfaces are concerned, they often have to be reworked or freed from production residues. Because the components grow layer by layer, they are not always as perfectly shaped as desired. Blasting systems are ideal for post-processing, in which abrasive media such as nut kernels or glass splinters impact the surface at an accelerated rate via an air flow and remove material in the process. How much material is removed depends, among other things, on the material of the component and the size and type of blasting agent. Know-how and sensitivity are therefore required: on the one hand, the surface roughness of the components should be efficiently minimized, and on the other hand, the components must not melt or burn.
Understanding of the processes greatly improved
But what changes can be achieved with which blasting media? Or, to put it another way: Which blasting agent has which effect? Researchers from the Fraunhofer Institute for Production Engineering and Automation IPA have now answered these questions together with the company MST Microstrahltechnik, thereby greatly improving the understanding of these processes.
“We processed various 3D printed plastic components with different blasting media and compared the effects,” says Mark Becker, scientist at Fraunhofer IPA.
The components used were 3D printed geometries with corners and edges as well as thin wall and column elements made of three different materials: polyamide, PLA and PEEK. The researchers processed these components using three abrasive materials, which varied slightly from printing material to printing material. The company MST Microstrahltechnik primarily contributed its expertise in blasting media; the researchers at Fraunhofer IPA developed a semi-automated test setup to increase reproducibility – and compared the results with those achieved by manual processing with the blasting media . Were there burns in the area of the thin wall and column elements? How well was the surface roughness reduced?
“Especially in the series production of 3D printed components, it is helpful to adapt the abrasive material and the blasting process specifically to the component in order to get the best out of it,” Becker summarizes the findings.
This is exactly what Fraunhofer IPA and MST Microstrahltechnik offer interested companies: They optimize the blasting process on behalf of the customer for the respective components and support the selection of suitable blasting media.