Material study with Dressler Group, Fraunhofer and University of Bayreuth hailed as major milestone for circular economy.
With the ever-increasing demand for sustainability in manufacturing, you can expect more stories about repurposing waste powder for 3D printing in 2025. The latest comes from a materials study conducted by voxeljet, Dressler Group GmbH, Fraunhofer IPA and the University of Bayreuth. These found organizations have collaborated to reuse waste PA12 powder from laser-based additive manufacturing (AM) systems.
In the study, waste powder from selective laser sintering (SLS) systems was recycled by Dressler Group and 3D printed by Fraunhofer IPA at the University of Bayreuth using a VX200 HSS platform from voxeljet. According to voxeljet, the initial results demonstrate that reconditioned PA12 waste powder can be processed effectively using ink- and printhead-based high speed sintering (HSS) technology. Moreover, the company reports that the preliminary test results indicate the material properties of the test units are equal to or may even exceed those of comparable prints with fresh powder.
Normally, unprinted PA12 powder loses its ability to be reused due to high temperature exposure in the build area, which causes the polyamide chains to lengthen after condensation and negatively affects powder flowability and melt viscosity. This makes the material difficult to process again via laser-based technologies, since the energy input from lasers is too short to process the longer molecule chains.
The study aimed to reclaim this used powder by processing it through voxeljet’s VX200 HSS platform, which uses an inkjet-based printhead and infrared heating to allow the polyamide to sinter gradually, enabling its reuse.
“Recycling used PA12 powder can effectively reduce costs and support sustainability efforts in AM.” said Holger Leonards, head of R&D at Dressler Group in a voxeljet press release. “Our expertise in regenerating powder properties and handling of large powder volumes enables companies to reclaim this valuable material.”
“The VX200 HSS technology is an open-source system, allowing us to quickly change and adapt process parameters to any powder,” said Jan Kemnitzer, research team lead at Fraunhofer IPA, in the same release. “We were therefore able to quickly adapt the 3D printer to the material with consistent or improved results in part properties.”
“The results of this study are especially interesting for ink- and printhead-based technologies such as the HSS technology,” said Tobias Grün, global product management at voxeljet. “The future possibility of processing this recycled powder on production platforms like the VX1000HSS will bring immense cost savings. Typically, 50% of running costs are attributable to powder. Thus, this development provides a huge effect on cost effectiveness while boosting a circular material flow and reducing waste.”
voxeljet and Fraunhofer will be demonstrating the results of this study at their respective booths at Formnext 2024 in Frankfurt from November 19th to 22nd.
