Authors:
Felix Großwendt (1), Nick Hantke (2), Santiago Benito (1), Jan T. Sehrt (2), Sebastian Weber (1) and Jonathan Lentz (1)
1- Chair of Materials Technology, Ruhr University Bochum, Germany
2- Chair of Hybrid Additive Manufacturing, Ruhr University Bochum, Germany
Abstract:
With many commercially available alloys, powder bed fusion of metals using a laser beam (PBF-LB/M)
results in the formation of defects such as cracks due to high cooling rates. To obtain a broader variety of starting materials suitable for PBF-LB/M and specific applications, mixing powders, so-called in-situ alloying, using a modular powder design set is a promising approach. Unfortunately, in-situ alloying promotes chemically inhomogeneous components. In this work, different powder mixtures were analyzed and processed to obtain a carbon steel of specified composition. The samples were microstructurally characterized using several methods and compared to a pre-alloyed reference. The chemical homogeneity is statistically evaluated employing first-order variograms. It was found that the composition of the individual raw materials is decisive for the homogenization within the melt pool. Large scale homogenization is also influenced by the amount of raw material added. By carefully selecting the raw materials, almost complete in-situ homogenization was achieved in PBF-LB/M.
DOI:
https://doi.org/10.59499/EP246282740
