3D-printer for selective laser melting (SLM) with micro-focus and integratable plasma source

• Subject Area: Materials Engineering
• Term: Funded in 2022
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 501294239

Digitalization is currently driving the emergence of new processes and new products, and new business models. The familiar concepts are being displaced. In this sense, generative manufacturing processes or additive manufacturing (AM) are "disruptive". They enable new degrees in freedom of form and for customizability as well as originality of AM products. One of the most important processes here is "Selective Laser Melting" (SLM), which is used to generate industrially relevant components from metal powders. HAWK is already re-searching improved feedstock materials for this process, which gain their specific properties through plasma treatment. On the one hand, coatings are used to improve the flow proper-ties of powders with particle sizes around 1 µm, to reduce the formation of agglomerates, and thus to reduce the achievable structure size as well as to produce smoother surfaces. On the other hand, plasma treatment without deposition can modify the particle surface as well, for example by removing surface oxides. In addition, oxide ceramics, which often are non-absorbing in the near infrared at the usual laser wavelength of about 1 µm, can be reduced by plasma treatment so that they become absorbent in this spectral range and thus accessible to the process.Both approaches currently have their limits: Standard SLM printers are not designed to handle the aforementioned ultrafine powders. Therefore, specific µ-SLM equipment is re-quired to take advantage of the reduced particle sizes. Furthermore, the effects of the plasma surface treatments without coating are often short-lived. Therefore, the time be-tween treatment and printing has to be kept as short as possible; ideally, this treatment even happens in-situ.The requested device fulfills the requirements for highest resolution, short transfer times and the possibility to use in-situ plasma sources, and thus contributes significantly to the scientific progess in the individual research fields of the research focus "Laser and Plasma Technology" as well as the entire faculty "Engineering and Health".

• DFG Programme: Major Research Instrumentation
• Major Instrumentation: 3D-Drucksystem für selektives Laserschmelzen (SLM) mit Mikrofokus und integrierbarer Plasmaquelle
• Instrumentation Group: 5740 Laser in der Fertigung
• Applicant Institution: Hochschule für angewandte Wissenschaft und Kunst; Hildesheim/Holzminden/Göttingen
• Leader: Professor Dr. Wolfgang Viöl