@article{KneisslWarnckSchnecketal.2022, author = {Kneißl, Barbara and Warnck, Moritz and Schneck, Matthias and Schmitt, Matthias and Schlick, Georg}, title = {Optimisation of a hydraulic housing for a brake-by-wire system for electrical drives by additive manufacturing}, volume = {2022}, journal = {Procedia CIRP}, number = {107}, publisher = {Elsevier}, address = {Amsterdam}, issn = {2212-8271}, doi = {https://doi.org/10.1016/j.procir.2022.05.039}, pages = {641 -- 646}, year = {2022}, abstract = {Electrical drives in automotive applications require new brake concepts, e.g. to allow recuperation mode. One approach for these are brake-by-wire systems, which are utilized in electrical motorsports. Based on the design freedom of Additive Manufacturing (AM), in particular laser-based powder bed fusion, a function-integrated hydraulic housing for such brake-by-wire systems is developed. The hydraulic housing is a core component of the brake system, as it holds all electric and hydraulic devices and a complex channel system to link the hydraulic devices. Thus, it must fulfill mechanical and hydraulic requirements, as well as a lightweight design in general. Based on a morphological box, which integrates already existing technical approaches and bionic solution principles, two prototypes were developed: One is derived from a current, conventionally manufactured hydraulic housing, and another one, utilizing the AM-capabilities to full extent. Both designs were developed utilizing three CAD tools, in particular Creo Parametric™ for the design itself, Inspire™ for topology optimisation and FEM calculation, and nTopology to generate ripples and lattices, like Voronoi structures. To develop a complex AM-design utilizing different software tools required several manual process steps. Thereby, insufficient software integration was identified as a hindrance to generate complex designs. Finally, both prototypes were manufactured by laser-based powder bed fusion from the aluminum alloy AlSi10Mg. Further optimisation potential exists, but could not be exploited due to insufficient material models for the mechanical design, e.g. fatigue data. Availability of calculation methods for lifetime prediction was identified as another limitation in the design process.}, language = {en} } @article{SchmittGottwaltWinkleretal.2021, author = {Schmitt, Matthias and Gottwalt, Albin and Winkler, Jakob and Tobie, Thomas and Schlick, Georg and Stahl, Karsten and Tetzlaff, Ulrich and Schlip, Johannes and Reinhart, Gunther}, title = {Carbon Particle In-Situ Alloying of the Case-Hardening Steel 16MnCr5 in Laser Powder Bed Fusion}, volume = {11}, pages = {11060896}, journal = {Metals}, number = {6}, publisher = {MDPI}, address = {Basel}, issn = {2075-4701}, doi = {https://doi.org/10.3390/met11060896}, year = {2021}, abstract = {The carbon content of steel affects many of its essential properties, e.g., hardness and mechanical strength. In the powder bed fusion process of metals using a laser beam (PBF-LB/M), usually, pre-alloyed metal powder is solidified layer-by-layer using a laser beam to create parts. A reduction of the carbon content in steels is observed during this process. This study examines adding carbon particles to the metal powder and in situ alloying in the PBF-LB/M process as a countermeasure. Suitable carbon particles are selected and their effect on the particle size distribution and homogeneity of the mixtures is analysed. The workability in PBF-LB is then shown. This is followed by an evaluation of the resulting mechanical properties (hardness and mechanical strength) and microstructure in the as-built state and the state after heat treatment. Furthermore, potential use cases like multi-material or functionally graded parts are discussed.}, language = {en} }