A priori process parameter adjustment for SLM process optimization

Selective Laser Melting (SLM) is a layerwise production technique enabling the production of complex metallic parts. In the SLM process parts are built by selectively melting subsequent layers of powder by a laser beam. Nowadays a SLM machine is provided with a fixed scan strategy (laser power, scan velocity and scan pattern) throughout the full build process. However, the part's geometry has a large influence on the stability of the process and therefore the quality of some features like for instance thin walls, sharp corners, down facing layers (layers above powder), is often poor. This problem can be overcome by using knowledge of the geometry a priori. This paper presents a methodology to detect critical features in the model of the part, based on the slicing data. In this way these critical features can then be processed with optimized parameters. As a proof of concept this a priori parameter adaptation methodology is applied on production overhang.