High Throughput Characterization of Mechanical Properties of Electron Beam Additive Manufactured High-Speed Steel

Abstract Additive manufacturing of metals by electron beam-based powder bed fusion (PBF-EB/M) is widely used for processing of numerous alloy systems. However, up to now there have been only a few studies investigating tool steels using PBF-EB/M. Due to high build chamber temperatures during processing, PBF-EB/M provides advantages for such steels. These conditions, for example, help to avoid cracks. In the present study, the high-speed steel (HSS) Böhler S390 Microclean (similar to M42, 1.3247) has been processed using PBF-EB/M. As a first step, two different parameter sets, i. e., two different resulting line energies and their effect on the resulting network-like cell structure, were investigated. Nanoindentation measurements revealed strong differences in hardness and elastic modulus between the network-like cell structures and the martensitic matrix, which could be attributed to the formation of carbides during solidification, which were probed by scanning electron microscopy. In addition, monotonic tensile properties were characterized on specimens built with a parameter set adapted to the geometry in order to consider one of the most critical loading scenarios for the tool steel in focus. The investigations reveal a high tensile strength with relatively low elongation at fracture.