Laser-Directed Energy Deposition of H13: processing window and improved characterization procedures

Additive manufacturing has the potential to create, repair, or enhance customized tools, but reliable processing guidelines for tool steels are necessary. This study focuses on printing H13 tool steel on a 316 L substrate using Laser-Directed Energy Deposition technology. A comprehensive study on the most influential process parameters was carried out, i.e. laser power (1400, 1600, 1800, 2000 W), powder feed rate (9, 12, 15 g/min) and scanning speed (1000, 1200 mm/min), for the production of single tracks. Cladding angle, aspect ratio, dilution, shift, microhardness, microstructures were selected as measured output. Manufacturing guidelines were established for a complete characterization of individual tracks, with a new approach for properly calculating the dilution. The tracks exhibited different properties and the influence of process parameters on the measured output was evaluated. The outcomes determine a technological window where it is possible to select the most sensible process parameters depending on the desired application.