From powder to component
Take metallic powder particles, add a powerful laser and produce a high-strength component. The recipe for the metallic 3D printing process "Selective Laser Melting" (SLM), which scientists from the Department of Lightweight Structures and Polymer Technology at Chemnitz University of Technology, Germany, are working on, is described in a nutshell.
The Scientists use titanium, aluminium and steel alloys as well as hybrid material composites for the metallic 3D printing process. "In general, easily weldable metals in powder form are particularly suitable for the SLM process," explains Frank Schubert, scientific assistant at the Department of Lightweight Structures and Polymer Technology. Processing takes place in an argon protective gas atmosphere in special plants. This results in components for use in aerospace, medical technology such as hip implants, machining tools such as milling cutters, prototypes for machines and functional components such as hydraulic components. They are characterized by a special manufacturing method of high strength, which enables them to easily compete with the quality of conventionally manufactured components. Compared to conventional welding or milling processes, the SLM process offers the advantage of complex component geometries, sometimes including movable elements such as joints, being produced within a single process and without the need for expensive, product-specific tools.
"We are able to manufacture prototypes, test specimens and components up to 25 centimeters in width and height in our research halls. Depending on the structure and requirements, the machines work from a few hours to several days. However, the actual work starts much earlier, because we develop optimal process parameters in advance to guarantee the highest possible material quality and process stability. In addition, we use topology optimization procedures for the development of components," says Schubert. The aim is to reduce the mass of the subsequent component in such a way that it is sufficient for the application, but the material is only applied in appropriate quantities where it is needed. This enables the researchers to be particularly resource-efficient - an important aspect in the field of lightweight construction.