Development of an efficient cycle of residual plastic powder from the laser sintering process

© Fraunhofer IWU

Additive manufacturing processes, which are generally summarized as 3D printing processes, are experiencing increasing demand, especially in the industrial sector. Selective laser sintering (SLS) is one of the most effective additive manufacturing processes for plastic components of high quality and good mechanical properties: by applying defined layers of plastic powder as well as selective melting and joining of the plastic particles by laser in desired areas, components are produced additively.

Compared to other additive processes, however, the SLS process is very cost-intensive and inefficient: only 8 percent of the expensive starting materials are converted into components, while at the same time the plastic powder from the remaining manufacturing space can only be reused to a limited extent due to contamination and the effects of heat. In order to make the SLS process more economical, the process must therefore be optimized and made more efficient through closing the material cycle.

In the “PowdeR²eSint” project, the project partners want to make the SLS process more resource-efficient. For this purpose, GEO Reinigungstechnik GmbH is developing an unpacking and de-powdering system for automated unloading of the printed components and the unused manufacturing space powder without contamination. In addition, the automated unpacking and de-powdering is to reduce the cycle time of this so far time-consuming process.

Furthermore, GS-Pro GmbH and Oerlikon AM are developing a recyclable powder mixture in order to realize a more resource-efficient, sustainable SLS process and to reduce the waste powder disposal volumes to a minimum. The Fraunhofer Institute for Machine Tools and Forming Technology IWU and the Chemnitz University of Technology are responsible for material characterization and materials research.