@article{GottwaltKubaschinskiWaltzetal.2023, author = {Gottwalt, Albin and Kubaschinski, Paul and Waltz, Manuela and V{\"o}lkl, Rainer and Glatzel, Uwe and Tetzlaff, Ulrich}, title = {Cyclic deformation behavior of non-oriented electrical steel sheets}, volume = {2023}, pages = {145684}, journal = {Materials Science and Engineering: A}, number = {886}, publisher = {Elsevier}, address = {Amsterdam}, issn = {0921-5093}, doi = {https://doi.org/10.1016/j.msea.2023.145684}, year = {2023}, language = {en} } @article{ViewegerDielSchweigeretal.2024, author = {Vieweger, Daniel and Diel, Sergej and Schweiger, Hans-Georg and Tetzlaff, Ulrich}, title = {Mechanical Properties of Raw Filaments and Printed Specimens: Effects of Fiber Reinforcements and Process Parameters}, volume = {16}, pages = {1576}, journal = {Polymers}, number = {11}, publisher = {MDPI}, address = {Basel}, issn = {2073-4360}, doi = {https://doi.org/10.3390/polym16111576}, year = {2024}, abstract = {Fused Deposition Modeling (FDM) is a well-established manufacturing method for producing both prototype and functional components. This study investigates the mechanical properties of FDM components by material and process-related influencing variables. Tensile tests were conducted on seven different materials in their raw filament form, two of which were fiber-reinforced, to analyze their material-related influence. To cover a wide range from standard to advanced materials relevant for load-carrying components as well as their respective variations, polylactic acid (PLA), 30\% wood-fiber-reinforced PLA, acrylonitrile butadiene styrene (ABS), polycarbonate (PC), a blend of ABS and PC, Nylon, and 30\% glass-fiber-reinforced Nylon were selected. The process-related influencing variables were studied using the following process parameters: layer thickness, nozzle diameter, build orientation, nozzle temperature, infill density and pattern, and raster angle. The first test series revealed that the addition of wood fibers significantly worsened the mechanical behavior of PLA due to the lack of fiber bonding to the matrix and significant pore formation. The polymer blend of ABS and PC only showed improvements in stiffness. Significant strength and stiffness improvements were found by embedding glass fibers in Nylon, despite partially poor fiber-matrix bonding. The materials with the best properties were selected for the process parameter analysis. When examining the impact of layer thickness on part strength, a clear correlation was evident. Smaller layer thicknesses resulted in higher strength, while stiffness did not appear to be affected. Conversely, larger nozzle diameters and lower nozzle temperatures only positively impacted stiffness, with little effect on strength. The part orientation did alter the fracture behavior of the test specimens. Although an on-edge orientation resulted in higher stiffness, it failed at lower stresses. Higher infill densities and infill patterns aligned with the load direction led to the best mechanical results. The raster angle had a significant impact on the behavior of the printed bodies. An alternating raster angle resulted in lower strengths and stiffness compared to a unidirectional raster angle. However, it also caused significant stretching due to the rotation of the beads.}, language = {en} } @article{GottwaltKubaschinskiWaltzetal.2024, author = {Gottwalt, Albin and Kubaschinski, Paul and Waltz, Manuela and Tetzlaff, Ulrich}, title = {Influence of Subsequent Heat Treatment on Fatigue Behavior of Shear-Cut Electrical Steel Sheets}, volume = {3}, journal = {Alloys}, number = {4}, publisher = {MDPI}, address = {Basel}, issn = {2674-063X}, doi = {https://doi.org/10.3390/alloys3040017}, pages = {281 -- 294}, year = {2024}, abstract = {The fatigue behavior of a fully processed, non-oriented electrical steel sheet is investigated in dependence on shear-cutting parameters and a subsequent heat treatment. For this, stress-controlled fatigue tests are performed before and after annealing at 700 °C for a total of six different shear-cutting settings. For all parameters, the fatigue strength of shear-cut sheets is improved by the heat treatment. This is due to reduction in a large part of the strain hardening region as well as the reduction in tensile residual stresses. Both were introduced during shear cutting and act detrimental to the fatigue strength. However, the intensity of this improvement depends on the shear-cutting parameters. This is related to the corresponding edge surfaces characteristically being formed during shear cutting. Specimens cut with a worn cutting tool show a more pronounced increase in fatigue life. In contrast, specimens produced with a sharp-edged cutting tool and high cutting clearance hardly benefit from the heat treatment. This appears to be caused by differences in surface topography, in particular coarse topographical damage in the form of grain breakouts. If these occur during shear cutting, the crack formation is not significantly delayed by additional annealing.}, language = {en} } @article{deSouzaPintoPereiraGutjahrPereiraetal.2023, author = {de Souza Pinto Pereira, Adriano and Gutjahr, Jhonattan and Pereira, Milton and Tetzlaff, Ulrich and Fredel, M{\´a}rcio Celso}, title = {Processability of thin-powdered Inconel X750 and TiC metal matrix composite by laser-directed energy deposition}, volume = {35}, pages = {042040}, journal = {Journal of Laser Applications}, number = {4}, publisher = {LIA}, address = {Orlando}, issn = {1042-346X}, doi = {https://doi.org/10.2351/7.0001134}, year = {2023}, language = {en} } @inproceedings{MohdKreinerSchmidetal.2024, author = {Mohd, Zubair Akhtar and Kreiner, Christian and Schmid, Maximilian and Zippelius, Andreas and Tetzlaff, Ulrich and Elger, Gordon}, title = {Fully Connected Neural Network (FCNN) Based Validation Framework for FEA Post Processing to Improve SAC Solder Reliability Analysis}, booktitle = {2024 IEEE 10th Electronics System-Integration Technology Conference (ESTC), Proceedings}, publisher = {IEEE}, address = {Piscataway}, isbn = {979-8-3503-9036-0}, doi = {https://doi.org/10.1109/ESTC60143.2024.10712023}, year = {2024}, language = {en} } @article{GuldenGramstatStichetal.2018, author = {Gulden, Florian and Gramstat, Sebastian and Stich, Anton and Hoppel, Heinz Werner and Tetzlaff, Ulrich}, title = {Properties and Limitation of an Oxide Coated Aluminum Brake Rotor}, pages = {2018-01-1877}, journal = {SAE Technical Paper}, publisher = {SAE}, address = {Warrendale}, issn = {0148-7191}, doi = {https://doi.org/10.4271/2018-01-1877}, year = {2018}, language = {en} } @article{VolpatodeSouzaPintoPereiraNeumeieretal.2025, author = {Volpato, Guilherme and de Souza Pinto Pereira, Adriano and Neumeier, Steffen and Hotza, Dachamir and G{\"o}ken, Mathias and Tetzlaff, Ulrich and Fredel, M{\´a}rcio Celso}, title = {Influence of a Standard Heat Treatment on the Microstructure and Properties of Inconel X-750 Produced by Laser Powder Bed Fusion}, volume = {27}, pages = {2500306}, journal = {Advanced Engineering Materials}, number = {24}, publisher = {Wiley}, address = {Weinheim}, issn = {1527-2648}, doi = {https://doi.org/10.1002/adem.202500306}, year = {2025}, abstract = {The production of nickel-base superalloys through powder bed fusion using a laser beam (PBF-LB) offers a promising method for reducing the cost of aeronautical components, especially those with complex geometries. However, when these materials are processed using PBF-LB, the standard heat treatments developed for conventional manufacturing routes do not consistently yield predictable microstructures or mechanical properties. Thus, this study analyzes how PBF-LB affects the microstructure and mechanical behavior of Inconel alloy X-750 when compared to a hot-rolled counterpart after undergoing a standard precipitation-hardening heat treatment (solution annealing, stabilization, and precipitation). Microstructure is examined using analytical electron microscopy and high-energy X-ray diffraction, while mechanical behavior is assessed through microhardness. Significant differences between both manufacturing routes are detected, so that PBF-LB processing led to an increase in grain size, anisotropy, fraction of low-angle grain boundaries, mean angle of misorientation, and dislocation density. Moreover, PBF-LB promoted the formation of γ′-Ni3(Al,Ti) and η-Ni3Ti phases during solution annealing and stabilization, respectively. Notably, the formation of γ′ contributes to an anomalous microhardness increase observed between these steps. These findings suggest that PBF-LB may inhibit recrystallization and facilitate precipitation during heat treatment, thereby affecting the performance of components produced using this technology.}, language = {en} }