Resource-efficient add-on structures for the mechanical postprocessing of laser powder bed fusion parts using five-axis machining

The combination of the laser powder bed fusion of metals process (PBF-LB/M) with mechanical finishing using state-of-the-art machining centers enables the production of high-performance structural components with both internal and external complexity and precision. However, the sequential machining of additive manufactured parts can be challenging due to the need for multiple clamping setups and part-specific clamping devices. Postprocessing typically accounts for 20%–40% of manufacturing costs and can even double the cost of the final part. To reduce component costs, mechanical postprocessing should be considered. This study presents a novel concept for the development of resource-efficient add-on structures that can simplify mechanical postprocessing. These structures can either be applied to the part design prior to additive manufacturing or integrated into the part’s support structures. The developed structures allow the direct mounting of near-net-shape components on automatable, state-of-the-art parallel clamping systems. The structures are designed to clamp the parts with increased accessibility for five-sided simultaneous machining. The additional material costs are calculated within the work. The procedure for generating the add-on structures for additive manufacturing, using bounding box, topology, and shape optimization is presented. The mechanical behavior of the add-on structures is verified by clamping and measurement tests. The developments were validated by the manufacturing of three different components from the aerospace and laser technology sectors, using PBF-LB/M and aluminum alloy AlSi10Mg. The overall functionality of the add-on structures was validated by finishing the functional surfaces of the components and mechanically removing the support structures, using five-axis vertical milling centers.