Design Considerations for 3D Printing with Metal
3D printing proces most widely used is Direct Metal Laser Sintering (DMLS) for delivering fully dense metal parts and components. DMLS is an additive manufacturing process that consecutively melts designs in layers. When beginning a project for DMLS 3D printing, it’s important to remember a few key facts regarding design to ensure you’re optimizing your part for the process.
DMLS is a powder based 3D printing process, however unlike its plastic counterpart Laser Sintering, DMLS requires support structures which must be removed during post-processing. Support structures are required in most 3D printing processes. Support material is sometimes the same material as the final build, as with DMLS, or separate specially formulated material for easy release from the final part. Support structures are required during printing for a variety factors, either to ensure accuracy while a part completes the curing or hardening process or to maintain tolerances and shape for delicate features. In the case of DMLS, once the metal is sintered it becomes denser than the surrounding unsintered powder and can therefore sink through the powder and break off the part or otherwise warp without support structures in place. DMLS parts can also experience “burn” (melt deformation) when delicate features are left unsupported because DMLS metals are being melted at extremely high temperatures. Recommended that any angle below 45° incorporate supports and that wall thickness (while geometry depending) maintain a ratio of 8:1 between thickness and height.