TY - GEN A1 - Sydow, Benjamin A1 - Jhanji, Avantika A1 - Hälsig, André A1 - Buhl, Johannes A1 - Härtel, Sebastian T1 - The Benefit of the Process Combination of Wire Arc Additive Manufacturing (WAAM) and Forming—A Numerical and Experimental Study T2 - Metals KW - WAAM KW - forming KW - process combination KW - simulation KW - recrystallization KW - hardness KW - heat treatment cycle KW - fine grained mild steel KW - microstructure evolution Y1 - 2022 U6 - https://doi.org/10.3390/met12060988 SN - 2075-4701 VL - 12 IS - 6 ER - TY - GEN A1 - Emdadi, Aliakbar A1 - Bolz, Sebastian A1 - Buhl, Johannes A1 - Weiß, Sabine A1 - Bambach, Markus T1 - Laser Powder Bed Fusion Additive Manufacturing of Fe3Al-1.5Ta Iron Aluminide with Strengthening Laves Phase T2 - Metals Y1 - 2022 U6 - https://doi.org/10.3390/met12060997 SN - 2075-4701 VL - 12 IS - 6 ER - TY - GEN A1 - Ertugrul, Gökhan A1 - Hälsig, Andre A1 - Hensel, Jonas A1 - Buhl, Johannes A1 - Härtel, Sebastian T1 - Efficient Multi-Material and High Deposition Coating including Additive Manufacturing by Tandem Plasma Transferred Arc Welding for Functionally Graded Structures T2 - Metals KW - additive manufacturing powder KW - 3D Plasma Metal Deposition (3DPMD) KW - austenitic stainless steel KW - super-duplex stainless steel KW - multi-material KW - functionally graded KW - high deposition rate KW - arc KW - powder Y1 - 2022 U6 - https://doi.org/10.3390/met12081336 SN - 2075-4701 VL - 12 IS - 8 SP - 1 EP - 17 ER - TY - GEN A1 - Omair, Muhammad A1 - Alkahtani, Mohammed A1 - Ayaz, Kashif A1 - Hussain, Ghulam A1 - Buhl, Johannes T1 - Supply Chain Modelling of the Automobile Multi-Stage Production Considering Circular Economy by Waste Management Using Recycling and Reworking Operations T2 - Sustainability N2 - The supply chain management plays a crucial role in delivering products from a supplier, through the manufacturer, distributors, and retailers to the targeted customers. The lifecycle of the products can be ended at any stage due to imperfect quality or waste, which are typically not managed well for a good price. This product’s life can be extended and increased with the use of the circular economy for the value addition processes which turn the waste into byproducts, which can be sold with maximum profit. The automobile industry is associated with various other small industries and is very significant for the economy at the local, national, and international levels. However, the industry also requires sustainable development in its supply chain management, gained by introducing the circular economy concept to manage and reduce the generated waste. The consumption of carbon fiber-reinforced composites (CFRCs) in the manufacturing of numerous automotive parts has acquired immense attention this decade, but the process also generates imperfect products (waste). The proposed model is based on a mathematical formulation to manage imperfect production by reworking and recycling, where the former is required to re-add value to the proportion of the rejected parts, and the latter is to recycle the remaining scrap into useful products by using a circular economy. The outsourcing operation is also added to provide an optimal level of inventory and lot sizing for minimizing the total cost of the supply chain management. Data from the automobile part industry are tested to provide the practical implications of the proposed SCM mathematical model. Sensitivity analysis is performed to understand the significance level of the individual parameters affecting the objective function, i.e., the total cost of the SCM. The results show a meaningful insight for the managers to obtain the benefits of the circular economy in multi-stage automobile part production for sustainable and resilient supply chain management. KW - supply chain management KW - circular economy KW - automotive industry KW - outsourcing KW - imperfect production Y1 - 2022 U6 - https://doi.org/10.3390/su142215428 SN - 2071-1050 VL - 14 IS - 22 ER - TY - GEN A1 - Scharf-Wildenhain, Ronny A1 - Hälsig, André A1 - Härtel, Sebastian A1 - Wandtke, Karsten A1 - Schröpfer, Dirk A1 - Kromm, Arne A1 - Kannengießer, Thomas T1 - Einfluss der Wärmeführung auf die Eigenschaften und fertigungsbedingten Beanspruchungen additiv geschweißter hochfester Feinkornbaustähle T2 - 42. Assistentenseminar Fügetechnik KW - Additive Fertigung; Eigenspannungen; Hochfester Stahl; Kaltrisssicherheit; MAG-Schweißen Y1 - 2022 SN - 978-3-96144-210-2 SP - 94 EP - 101 PB - DVS Media GmbH CY - Düsseldorf ER - TY - GEN A1 - Hussain, Ghulam A1 - Alkahtani, Mohammed A1 - Alsultan, Marwan A1 - Buhl, Johannes A1 - Gupta, Munish Kumar T1 - Chip formation, cutting temperature and forces measurements in hard turning of Gcr15 under the influence of PcBN chamfering parameters T2 - Measurement KW - Chamfering width KW - Chamfering angle KW - DEFORM KW - Hard turning Y1 - 2022 U6 - https://doi.org/10.1016/j.measurement.2022.112130 SN - 1873-412X SN - 0263-2241 VL - Vol. 204 ER - TY - GEN A1 - Hirtler, Markus A1 - Ünsal, Ismail A1 - Buhl, Johannes A1 - Bambach, Markus T1 - Investigation of quench hardening behavior of directed energy deposited 22MnB5 steel for local reinforcement of hot stamping parts T2 - CIRP Journal of Manufacturing Science and Technology KW - 22MnB5 KW - Directed Energy Deposition KW - Hardenability KW - Critical cooling rate KW - Dilatometry KW - Boron nitride KW - Mill scale Y1 - 2022 U6 - https://doi.org/10.1016/j.cirpj.2022.08.003 SN - 1878-0016 SN - 1755-5817 VL - Vol. 39 SP - 223 EP - 231 ER - TY - GEN A1 - Colditz, Pascal A1 - Härtel, Sebastian A1 - Drehmann, Rico T1 - Numerical and Experimental Modeling of an Inline Forming Process for the Mechanical Property Optimization of Cold Gas Sprayed Material Composites T2 - Production at the Leading Edge of Technology : Proceedings of the 11th Congress of the German Academic Association for Production Technology (WGP), Dresden, September 2021 KW - Cold gas spraying Composite material Titanium Hybrid process Y1 - 2022 SN - 978-3-030-78423-2 SN - 978-3-030-78426-3 SN - 978-3-030-78424-9 U6 - https://doi.org/10.1007/978-3-030-78424-9_41 SN - 2194-0533 SP - 366 EP - 374 PB - Springer CY - Cham ER - TY - GEN A1 - Hart-Rawung, Thawin A1 - Buhl, Johannes A1 - Härtel, Sebastian A1 - Bambach, Markus T1 - Intelligent Iterative Experimental Design to Achieve Maximum Model Quality for Phase Change of 22MnB5 T2 - Key Engineering Materials Y1 - 2022 U6 - https://doi.org/https://doi.org/10.4028/p-0cnty5 VL - 926 SP - 2031 EP - 2039 PB - Verlag Trans Tech Publications Ltd ER - TY - GEN A1 - Besong, Lemopi Isidore A1 - Buhl, Johannes A1 - Härtel, Sebastian A1 - Bambach, Markus T1 - Increasing the Forming Limits in Hole Flanging of Dual-Phase (DP) 1000 Steel Using Punch Rotation T2 - Key Engineering Materials KW - Frictional Heat KW - High Formability KW - Hole Flanging KW - Punch Rotation Y1 - 2022 U6 - https://doi.org/10.4028/p-06y8un SN - 1662-9795 VL - Vol. 926 SP - 717 EP - 723 ER - TY - GEN A1 - Afzal, Muhammad Junaid A1 - Buhl, Johannes T1 - Numerical Study to Promote the Residual Stresses Development during ISF Process with Improvement in Two Point Incremental Die Forming T2 - Key Engineering Materials KW - Disc springs KW - Martensite transformation KW - Residual stresses KW - Cooling channels KW - Incremental sheet forming KW - Austenite phase Y1 - 2022 SN - 1662-9795 VL - Vol. 926 SP - 752 EP - 759 ER - TY - RPRT A1 - Buhl, Johannes A1 - Butz, Alexander A1 - Wessel, Alexander A1 - Morand, Lukas T1 - Intelligente Werkstoffprüfung mit automatisierter Versuchsplanung und Modellidentifikation Y1 - 2022 SN - 978-3-86776-639-5 PB - Euroäische Forschungsgesellschaft für Blechverarbeitung CY - Hannover ER - TY - GEN A1 - Imran, Muhammad A1 - Deillon, Léa A1 - Sizova, Irina A1 - Neirinck, Bram A1 - Bambach, Markus T1 - Process optimization and study of the co-sintering behaviour of Cu-Ni multi-material 3D structures fabricated by spark plasma sintering (SPS) T2 - Materials & Design KW - Multi-material KW - Spark plasma sintering KW - Sintering behavior KW - Master sintering curve KW - Master sintering surface Y1 - 2022 U6 - https://doi.org/10.1016/j.matdes.2022.111210 SN - 0264-1275 VL - Vol. 223 ER - TY - GEN A1 - Fischer, Tim Sebastian A1 - Grüger, Lennart A1 - Woll, Ralf T1 - Additive Manufacturing: A Step-by-Step Guide T2 - Industry 4.0 Science N2 - New technologies have enabled additive manufacturing to construct components layer by layer using 3D model data. Machinery requirements for this are minimal, entailing only a welding device for energy input and a guiding machine to shape the component. Though there are clear benefits to the process, such as the cost-effective technology and high deposition rates, the complex interactions involved must receive due consideration. KW - process visualization KW - Additive Manufacturing KW - Wire Arc Additive Manufacturing KW - WAAM KW - Structured Analysis and Design Technique KW - SADT KW - welding KW - manufacturing KW - metal components KW - slicing KW - arc welding KW - deposition rate KW - machining centers KW - wire feed rate Y1 - 2023 U6 - https://doi.org/10.30844/I4SE.23.1.80 SN - 2942-6162 IS - 1 SP - 80 EP - 88 ER - TY - GEN A1 - Grüger, Lennart A1 - Fischer, Tim Sebastian A1 - Woll, Ralf A1 - Buhl, Johannes T1 - Absicherung von Risiken beim Prozess des Wire Arc Additive Manufacturing T2 - Industry 4.0 Science KW - Additive Manufacturing KW - Wire Arc Additive Manufacturing KW - Failure Mode and Effects Analysis Y1 - 2024 U6 - https://doi.org/10.30844/I4SD.24.1.63 SN - 2942-6154 VL - 2024 IS - 1 SP - 63 EP - 69 ER - TY - GEN A1 - Grüger, Lennart A1 - Fischer, Tim Sebastian A1 - Woll, Ralf A1 - Buhl, Johannes T1 - Safeguarding Against Risks in the Wire Arc Additive Manufacturing Process T2 - Industry 4.0 Science N2 - In this article, the potential risks in wire arc additive manufacturing are analyzed using failure mode and effects analysis. To achieve this, 186 possible causes of risk were analyzed and the five most critical risks were discussed in detail. Four significant risk factors were identified in the construction process. The fifth risk relates to the shielding gas flow. This is only one influencing factor among the welding parameters, which have strong interactions with each other. Therefore, their relationships should be analyzed on the basis of numerous tests. KW - additive manufacturing KW - wire arc additive manufacturing KW - failure mode and effects analysis Y1 - 2024 U6 - https://doi.org/10.30844/I4SE.24.1.63 SN - 2942-6170 VL - 2024 IS - 1 SP - 63 EP - 69 ER - TY - CHAP A1 - Grüger, Lennart A1 - Fischer, Tim Sebastian A1 - Woll, Ralf ED - Gapiński, Bartosz ED - Ciszak, Olaf Stanisław ED - Ivanov, Vitalii ED - Machado, Jose Mendes T1 - Investigation of the Wire Arc Direct Energy Deposition-Process and Possible Interactions T2 - Advances in Manufacturing IV N2 - The Wire Arc Direct Energy Deposition (WA-DED) process is highly regarded as part of additive manufacturing. Compared to other additive manufacturing processes, it is characterized above all by its high deposition rate and low system costs. Despite many years of experience in the build-up welding process, WA-DED still holds a number of challenges in terms of process stability. This article analyses the interactions in the WA-DED process. To this end, the process was visualized and described with the help of Structured Analysis and Design Technique (SADT). Building on this, a process Failure Mode and Effects Analysis (FMEA) was presented to identify and priorities risks. Finally, the results of the Taguchi tests were analyzed and visualized. The results illustrate the strong interactions between the influencing factors. These have a material-specific effect on the production results. Each new material composition therefore requires a systematic analysis in order to determine quantitative correlations. In future, these can be supported by machine learning approaches. KW - Additive Manufacturing KW - Structured Analysis and Design Technique KW - Failure Mode and Effects Analysis KW - Design of Experiments Y1 - 2024 SN - 9783031564659 U6 - https://doi.org/10.1007/978-3-031-56463-5_14 SN - 2195-4356 VL - 2024 SP - 176 EP - 194 PB - Springer Nature Switzerland CY - Cham ET - 4 ER - TY - GEN A1 - Ertugrul, Gökhan A1 - Alimov, Artem A1 - Sviridov, Alexander A1 - Härtel, Sebastian T1 - Machine learning application for optimization of laser directed energy deposition process for aerospace component rapid prototyping in additive manufacturing T2 - Materials Research Proceedings N2 - Abstract. The paper proposes a methodology for determining the optimal L-DED parameters based on the minimum number planned of L-DED trials. A dataset compiled from planned L-DED experiments was used to train a machine learning model. The algorithm demonstrated a robust ability to predict the output metrics with notable accuracy and proposed a theoretical framework that modeled the complex relationships between the input variables and the resulting critical welding properties for AM. The application of the developed model and its comparison with conventional methods thus offers a methodical approach to determining the optimum process parameters in advance. This is a step towards the development and production of additively manufactured components for future digital twin application in the aerospace industry. Y1 - 2024 U6 - https://doi.org/10.21741/9781644903131-31 SN - 2474-395X VL - 41 SP - 271 EP - 282 PB - Taylor&Francis ER - TY - GEN A1 - Schmidt, Alexander A1 - Emdadi, Aliakbar A1 - Härtel, Sebastian T1 - A holistic approach for near-net-shape processing of iron aluminides by means of Laser Directed Energy Deposition with cored wires T2 - 77th IIW Annual assembly and international conference on welding and joining, 7-12 July 2024, Rhodes N2 - Iron aluminides are characterized by high corrosion resistance, excellent mechanical properties and dimensional stability at high temperatures. With a low density this material offers technological and economic advantages over Ni-based alloys in the aerospace sector. Because of the excellent mechanical properties machining is the current challenge in processing Fe-Al. Due to the possibility of near-net-shape manufacturing along with high material efficiency additive manufacturing processes such as L-DED with wires seem to be predestined for the processing of Fe-Al. In this paper, a holistic approach for processing Fe-Al including manufacturing of wires and the actual processing of the wires is described. Since the wire drawing of iron aluminides is not possible due to low forming characteristics, a rotary swaging process was applied for manufacturing cored wires with a steel shell and aluminum core. On the one hand, the usage of unalloyed raw materials with suitable forming properties are advantageous. On the other hand, cored wires require in-situ alloying of the steel shell and aluminum core during the application process. Thus, the weldability of such cored wires was investigated in preliminary tests, initially using a tungsten inert gas welding process. The wires and the welding results were characterized by scanning electron microscopy, hardness measurement, and X-ray analyses. Y1 - 2024 UR - www.erasmuscorp.gr/IIW2024/ProceedingFiles/FP375.pdf VL - 2024 ER - TY - GEN A1 - Jensch, Felix A1 - Eissing, Katharina A1 - Richard, Williams A1 - Trautmann, Marcus A1 - Yang, Yitong A1 - Dubinin, Sergej A1 - Härtel, Sebastian T1 - Improving the structural integrity of challenging to manufacture LPBF components with toolpath correction T2 - Materials Research Proceedings N2 - This work deals with the influence of optimised exposure strategies on the distortion and microstructure of components susceptible to overheating and warpage. Therefore, different distortion-prone specimen geometries of 316L were fabricated with the standard parameters, as well as with exposure strategies optimised by machine learning, which were generated using the AMAIZE software package. The manufactured samples were analysed with regard to distortion. The results of the distortion analysis were then linked with the results of the digital tomography from AMAIZE. Furthermore, components were manufactured that tend to overheat due to their geometry and orientation on the substrate plate. The influence of overheating during the LPBF process on the microstructure and porosity was investigated along the build-up direction by means of an EBSD analysis and a porosity analysis. With the presented approach for optimising the exposure strategy with AMAIZE, it could be shown that a successful production of distortion- prone components with a porosity of less than 1 % is possible in the first trial. KW - LPBF-Process, Machine Learning, Microstructural Investigation Y1 - 2024 UR - https://d21zja6o12zyp0.cloudfront.net/9781644903131.pdf U6 - https://doi.org/10.21741/9781644903131-12 SN - 2474-395X VL - 41 SP - 110 EP - 119 PB - Materials Research Forum LLC ER - TY - GEN A1 - Grüger, Lennart A1 - Jensch, Felix A1 - Dittrich, Fabian A1 - Härtel, Sebastian T1 - On the creation of a material bond between L-PBF-manufactured AZ91 and Ti-6Al-4V components in the context of medical applications T2 - Materials N2 - Within the scope of these investigations, the feasibility of a material bond between Ti-6Al-4V and the magnesium alloy AZ91 is analyzed. Ti-6Al-4V is frequently used for implants due to its biocompatibility, corrosion resistance, and specific strength. However, depending on the surface quality, the attachment behavior of the bone to the implant varies. Magnesium implants promote the regeneration of bone tissue and biodegrade as the bone tissue heals. Combining the properties of both materials in one implant enables a reduced implant volume and increased stability. For this reason, this study aims to demonstrate the feasibility of creating a material bond between the materials Ti-6Al-4V and AZ91. For this purpose, Ti-6Al-4V truncated cones and AZ91 sleeves were produced using the additive manufacturing process of laser powder bed fusion (L-PBF). The as-built sleeves were then pressed onto machined truncated cones. Since zinc serves as a lubricant and has good diffusion properties with the materials used as a result of heat treatment, a comparison was made between zinc-coated and the as-built Ti-6Al-4V samples. This showed that a bond was created after hot isostatic pressing and that the push-out force could be increased by more than 4.5 times. Consequently, a proof of feasibility was demonstrated, and a high potential for applications in medical technology was shown. KW - AZ91 KW - Ti6-Al-4V KW - L-PBF KW - implant technology Y1 - 2024 U6 - https://doi.org/10.3390/ma17184667 SN - 1996-1944 VL - 17 IS - 18 PB - MDPI AG ER - TY - GEN A1 - Apel, Markus A1 - Härtel, Sebastian A1 - Szyndler, Joanna T1 - Prediction of the microstructure morphology after the WAAM process based on the FEM simulation results T2 - Materials Research Proceedings N2 - To improve understanding of the material behavior of additive-produced components, this paper focuses on the development of a numerical model that reproduces a Wire Arc Additive Manufacturing (WAAM) process, with particular attention given to the evolution of the microstructure. In this study, a finite element model in Simufact Welding software is developed, that replicates a real wire arc welding process of building a multilayer straight wall. Microscopy analysis of the weld wall cut in the middle of its length gave information about the expected microstructure morphology at different levels of the build wall. The whole experimental setup is reproduced in the software Simufact Welding. Simulation results in the form of temperature-time and temperature gradient-time history are then used as superimposed thermal conditions to simulate the microstructure evolution at different areas of the welded part by using MICRESS software. Y1 - 2024 U6 - https://doi.org/10.21741/9781644903131-3 VL - 41 SP - 22 EP - 31 ER - TY - GEN A1 - Härtel, Sebastian A1 - Szyndler, Joanna A1 - Pakdel Sefidi, Moein A1 - Jäger, Reyk T1 - Prediction of the evolution of material properties during the AM process based on the FEM simulation and experimental results T2 - Materials Research Proceedings N2 - To deepen the understanding of material behavior after additive manufacturing, this article focuses on the prediction of material properties after the Wire Arc Additive Manufacturing (WAAM) process. Particular attention is put on the temperature curves in the various phases of the welding process, which influence the final material properties, especially the hardness of the resulting part. A total of nine components in the form of walls were produced using the WAAM process, with the number of layers varying from 1 to 9. By experimentally analyzing the welded parts, which were cut in the middle of their length, it was possible to gain insights into the development of hardness at selected points. The entire test setup was simulated in the Simufact Welding FE-software. The simulation results in the form of temperature-time diagrams were then correlated with the real hardness measurements at the corresponding points. In this way, a model was developed that for the first time considers the development of hardness as a result of cooling after the welding process as well as the change in hardness as a result of reheating due to the application of additional layers. Y1 - 2024 U6 - https://doi.org/10.21741/9781644903131-5 VL - 41 SP - 40 EP - 49 ER - TY - GEN A1 - Grüger, Lennart A1 - Härtel, Sebastian A1 - Sahin, Emre T1 - Simulierte Produktionsumgebung heute – Evaluation der numerischen Prozesssimulation des selektiven Laserschmelzens T2 - Industry 4.0 Science Y1 - 2024 U6 - https://doi.org/10.30844/I4SD.24.4.70 SN - 2942-6154 VL - 2024 IS - 4 SP - 70 EP - 77 PB - GITO mbH Verlag ER - TY - GEN A1 - Bambach, Markus A1 - Ünsal, Ismail A1 - Sviridov, Alexander A1 - Hama-Saleh, Rebar A1 - Weisheit, Andreas T1 - Hybrid manufacturing of sheet metals and functionalizing for joining applications via hole flanging T2 - Production Engineering KW - Hybrid manufacturing KW - Laser metal deposition KW - Lightweight design KW - Hole flanging Y1 - 2021 U6 - https://doi.org/10.1007/s11740-020-01016-0 SN - 0944-6524 SN - 1863-7353 VL - 15 IS - 2 SP - 223 EP - 233 ER - TY - GEN A1 - Jensch, Felix A1 - Buhl, Johannes A1 - Laue, Robert A1 - Härtel, Sebastian T1 - Application of the plane-strain-compression-test to determine the local mechanical properties of LPBF-manufactured 316l components T2 - Material Forming: The 26th International ESAFORM Conference on Material Forming, Kraków, Poland, April 19-21, 2023 KW - LPBF-Process, Local Properties, Plane-Strain-Compression-Test Y1 - 2023 U6 - https://doi.org/10.21741/9781644902479-17 VL - 28 SP - 149 EP - 149 ER - TY - GEN A1 - Jedynak, Angelika A1 - Ertugrul, Gökhan A1 - Neumann, Andreas A1 - Pippig, Robert A1 - Härtel, Sebastian T1 - Semi-finished powder of aluminum matrix composite for a direct energy deposition additive manufacturing T2 - Material Forming: The 26th International ESAFORM Conference on Material Forming, Kraków, Poland, April 19-21, 2023 KW - Aluminum-Matrix Composites (AMCs), Direct-Vacuum-Casting (DVC), Direct Energy Deposition (DED), Additive Manufacturing (AM) Y1 - 2023 U6 - https://doi.org/10.21741/9781644902479-22 VL - 28 SP - 199 EP - 206 ER - TY - GEN A1 - Szyndler, Joanna A1 - Schmidt, Alexander A1 - Härtel, Sebastian T1 - Determination of welding heat source parameters for fem simulation based on temperature history and real bead shape T2 - Material Forming : The 26th International ESAFORM Conference on Material Forming, Kraków, Poland, April 19-21, 2023 KW - Finite Element Method (FEM), Wire Arc Additive Manufacturing (WAAM), Calibration Procedure, Goldak’s Heat Source Parameters Y1 - 2023 U6 - https://doi.org/10.21741/9781644902479-18 SP - 159 EP - 168 ET - 28 ER - TY - RPRT A1 - Grüger, Lennart A1 - Sydow, Benjamin A1 - Woll, Ralf A1 - Buhl, Johannes T1 - Design of a Cost-Effective and Statistically Validated Test Specification with Selected Machine Elements to Evaluate the Influence of the Manufacturing Process with a Focus on Additive Manufacturing N2 - Due to their versatile advantages, the use of additively manufactured components is growing. In addition, new additive manufacturing processes are constantly being developed, so that a wide range of printing processes are now available for metal. Despite the same starting material, the microstructure and thus also the final mechanical properties differ greatly compared to conventional processes. In most cases, only direction-dependent characteristic values from the uniaxial tension are used to qualify a printing process before it is used. The literature, on the other hand, demonstrates that the results are not transferable to other loading conditions. In this work, several engineering tests were integrated into a single test specimen so that they can be determined on the same specimen. The test specimen can be used to test tooth root strength, bending strength, notched bar impact energy, and thread strength depending on the mounting direction, thus representing industrial loading cases. In this study, test specimens were fabricated by conventional manufacturing (machining), L-PBF (Laser Powder Bed Fusion), and WA-DED (Wire Arc Direct Energy Deposition), and the results were compared using statistical methods. Factors to capture manufacturing influence and buildup direction were statistically validated on 316L. The work shows a benchmark with a typical initial microstructure of rolled and milled material, L-PBF, and WA-DED parts on loads close to the application and thus simplifies an industry-oriented evaluation of a new manufacturing process. KW - manufacturing factor KW - testing specification KW - laser powder bed fusion KW - wire arc direct energy deposition KW - 316L KW - significance KW - statistical method KW - benchmark geometry Y1 - 2023 UR - https://www.mdpi.com/2075-4701/13/11/1900 U6 - https://doi.org/https://doi.org/10.3390/met13111900 ER - TY - GEN A1 - Sydow, Benjamin A1 - Härtel, Sebastian ED - Mocellin, Katia ED - Bouchard, Pierre-Olivier ED - Bigot, Régis ED - Balan, Tudor T1 - Temperature Control During the Process Combination Welding and Rolling for Enabling Full Recrystallization with Homogenized Grain Size Distribution T2 - Proceedings of the 14th International Conference on the Technology of Plasticity : current trends in the technology of plasticity, ICTP 2023, volume 1 N2 - Welding with an electric arc is mainly used as a joining technology, where a high energy input is required locally for the joining process. Due to the heat input, the welded bead is characterized by a heat affected zone, that consists of an inhomogeneous microstructure of different phases and grain sizes. This leads to non-optimal mechanical properties. One way to improve the microstructure is to induce plastic deformation (e.g. by rolling), which can enable recrystallization mechanisms, that homogenize the microstructure and therefore can optimize the material properties. Yet, the recrystallization mechanisms require a minimum temperature to be activated. On one hand, the in-situ heat input during welding can be used for this in a process combination of welding and rolling but might not be enough, to reach or hold this recrystallization temperature during rolling. An excessive heat input on the other hand leads to too high temperatures, causing significant grain growth, that also negatively affect the mechanical properties. In any case, a certain temperature range over time has to be maintained. The temperature can be controlled by burners for pre-heating and post-heating, and the heating power can be controlled separately. In this numerical study, burner heat models are used to simulate the temperature-controlled process combination of welding one single bead with a subsequent rolling step for the mild steel St37/S235JR. The influence of the pre- and post-heating could be numerically proven and suitable heating combinations were found, that allow a full recrystallization with a nearly homogenous grain size distribution. Y1 - 2023 SN - 978-3-031-41022-2 SN - 978-3-031-41023-9 U6 - https://doi.org/10.1007/978-3-031-41023-9_20 SP - 192 EP - 202 PB - Springer CY - Cham ER - TY - RPRT A1 - Behrens, Bernd-Arno A1 - Krimm, Richard A1 - Fries, Stefan A1 - Härtel, Sebastian A1 - Schmidt, Alexander T1 - Eigenschaften individuell gefertigter Bauteile für Umformanlagen N2 - Die Dauerschwingfestigkeit ist eine wichtige sowie für die Auslegung von zyklisch belasteten Bauteilen in Umformmaschinen notwendige Materialkenngröße. Diese Kenngröße ist nicht nur material- sondern auch fertigungsprozessabhängig. Aufgrund der rapiden Entwicklung von additiven Fertigungsanlagen und Werkstoffen mangelt es an hinreichenden Erfahrungswerten zu den Betriebseigenschaften von additiv gefertigten Bauteilen. Daher ist es wichtig, die Eignung von additiv gefertigten Bauteilen für Umformmaschinen im Vorfeld technologisch und wissenschaftlich zu untersuchen. Die Ermittlung der Dauerschwingfestigkeit von additiv gefertigten Komponenten für Umformmaschinen liefert außerdem einen Mehrwert für die konstruktive Auslegung anderer AM-Bauteile mit einem vergleichbaren Belastungskollektiv und ermöglicht eine Topologieoptimierung von Komponenten von Umformmaschinen. Im Rahmen dieses Forschungsvorhabens wurde die Dauerschwingfestigkeit additiv gefertigter Bauteile in Abhängigkeit von der Gesamtheit der Herstellungsparameter eines WAAM-Prozesses sowie diverser Nachbehandlungsmethoden erfolgreich anhand des Fallbeispiels Pleuel ermittelt. Außerdem wurde die Anwendbarkeit von WAAM-Prozessen zur Herstellung von individuellen Anlagenbauteilen für den Bereich Umformmaschinen erfolgreich belegt. Mit den ermittelten Dauerschwingfestigkeitswerten konnte eine Grundlage zur Auslegung weiterer AM-Bauteile mit vergleichbaren Belastungskollektiv sowie Topologieoptimierung genannter Bauteile geschaffen werden. Die Untersuchungen erfolgten an Laborproben geeigneter Geometrie in Bezug auf das Realbauteil und unter Gewährleistung der thermischen Übertragbarkeit auf Realbauteile. Abschließend ist mittels eines skalierten Demonstratorbauteils die Machbarkeit nachgewiesen worden. Y1 - 2023 SN - 978-3-86776-660-9 CY - Hannover ER - TY - GEN A1 - Schmidt, Alexander A1 - Jensch, Felix A1 - Härtel, Sebastian T1 - Multi-material additive manufacturing-functionally graded materials by means of laser remelting during laser powder bed fusion T2 - Frontiers of Mechanical Engineering N2 - Many processes may be used for manufacturing functionally graded materials. Among them, additive manufacturing seems to be predestined due to near-net shape manufacturing of complex geometries combined with the possibility of applying different materials in one component. By adjusting the powder composition of the starting material layer by layer, a macroscopic and step-like gradient can be achieved. To further improve the step-like gradient, an enhancement of the in-situ mixing degree, which is limited according to the state of the art, is necessary. In this paper, a novel technique for an enhancement of the in-situ material mixing degree in the melt pool by applying laser remelting (LR) is described. The effect of layer-wise LR on the formation of the interface was investigated using pure copper and low-alloy steel in a laser powder bed fusion process. Subsequent cross-sectional selective electron microscopic analyses were carried out. By applying LR, the mixing degree was enhanced, and the reaction zone thickness between the materials was increased. Moreover, an additional copper and iron-based phase was formed in the interface, resulting in a smoother gradient of the chemical composition than the case without LR. The Marangoni convection flow and thermal diffusion are the driving forces for the observed effect. KW - multi-material additive manufacturing (MMAM) KW - functionally graded materials (FGMs) KW - laser powder bed fusion (L-PBF) KW - laser remelting (LR) KW - pure copper Y1 - 2023 UR - https://link.springer.com/article/10.1007/s11465-023-0765-z U6 - https://doi.org/10.1007/s11465-023-0765-z SN - 2095-0233 VL - 18 IS - 4 SP - 1 EP - 11 ER - TY - GEN A1 - Alimov, Artem A1 - Sviridov, Alexander A1 - Sydow, Benjamin A1 - Jensch, Felix A1 - Härtel, Sebastian T1 - Additive Manufacturing of Hot-Forming Dies Using Laser Powder Bed Fusion and Wire Arc Direct Energy Deposition Technologies T2 - Metals N2 - Additive technologies are now widely used for the production of complex precise parts and have high potential for the production of forming dies. In this work, hot-forming dies optimized for additive manufacturing were developed and produced with wire arc direct energy deposition (WA-DED) and laser powder bed fusion (L-PBF) technologies. The concept of lightweight hot-forming dies with a 2D-lattice structure was developed, which reduced the weight of each die by 56%, from 14.2 kg to 6.1 kg, in production using L-PBF. Maraging/precipitation-hardened steel 17-4PH was used as an alternative to traditional hot-working steels with slightly lower mechanical properties and a much higher processability in the additive manufacturing process. The workability of the manufactured dies was confirmed by forging tests on an industrial screw press. KW - additive manufacturing KW - hot-forming dies KW - L-PBF KW - WA-DED KW - WAAM Y1 - 2023 UR - https://www.mdpi.com/2075-4701/13/11/1842 U6 - https://doi.org/10.3390/met13111842 SN - 2075-4701 VL - 13 IS - 11 ER - TY - GEN A1 - Jäger, Reyk A1 - Sydow, Benjamin A1 - Schmidt, Alexander A1 - Witt, Susanne A1 - Härtel, Sebastian ED - Mocellin, Katia T1 - Design and Manufacturing of a Lightweight Press-Hardening Forming Tool by Wire Arc Additive Manufacturing T2 - Proceedings of the 14th International Conference on the Technology of Plasticity - Current Trends in the Technology of Plasticity, Volume 3 N2 - Press-hardening is an important metal sheet manufacturing process to improve the metal sheet properties during forming with an inline quenching process. This requires higher cooling rates often obtained by cooling channels within the tools, that enable the formation of martensite for a high strength. The manufacturing of those forming tools with internal cooling channels is quite complex, time and material consuming and therefore expensive. Optimal cooling channel geometry cannot be realized by conventional machining operations, that limits cooling efficiency too. Wire Arc Additive Manufacturing (WAAM) is a layer-wise welding process, that allows the manufacturing of near net shapes and internal cooling channels. In contrast to conventional machining, manufacturing of a complex lightweight design forming tool can be realized by WAAM. This will further reduce the WAAM process time and material consumption. However, the lightweight design reduces on one hand the thermal mass and thus the capability of heat transfer, making cooling via the cooling channels more crucial. On the other hand, elastic tool deformation has to be as low as possible. In this study, a press-hardening forming tool made of S235JR is designed and manufactured by means of WAAM. FEM analysis are performed to optimize the design of the forming tool regarding lightweight aspects. Simple near net shapes of cooling channels are considered for a simplification of the WAAM process. The forming tool is mechanically tested to compare and evaluate the stiffness with the FEM analysis. KW - lightweight forming tool KW - press-hardening KW - wire arc additive manufacturing KW - integrated surface cooling KW - CO2 balance Y1 - 2023 SN - 978-3-031-41340-7 SN - 978-3-031-41341-4 U6 - https://doi.org/10.1007/978-3-031-41341-4_25 SN - 2195-4364 SP - 235 EP - 246 PB - Springer ER - TY - GEN A1 - Neumann, Andreas A1 - Härtel, Sebastian ED - Mocellin, Katia T1 - Limitations of a new forming process for vault structured recuperator tubes T2 - Proceedings of the 14th International Conference on the Technology of Plasticity - Current Trends in the Technology of Plasticity ICTP 2023 - Volume 1 N2 - Classic forming technologies can make a difference to a climate-neutral economy. This also applies to the production of innovative hydrogen coolers (recuperators). To improve the efficiency of hydrogen coolers, heat transfer and heat flux can be increased by tube structures made by pressing spherical elements on their surface. Hydrogen is passed through the tubes of the recuperators and the cooling medium flows across it (Figure 1a). The tube serves as an atmosphere separator. Structured tubes can increase the power den-sity with the same dimensions. Figure 1b shows a process for introducing the structure into the pipe using radially and symmetrically arranged tools. Sheet metal forming usually involves pressing with structural tools, bending into a tube, and longitudinally welding. However, producing small tube diameters in the range of one inch presents a technical challenge. The challenge considered in this paper is to develop a new structuring process while maintaining the structural integrity and wall thickness of the tubes. This study aims to determine the feasibility of a multi-stage vault structuring process for recuperator tubes us-ing heat-resistant semi-finished products. KW - Forming limit, model-based evaluation, Tool Development Y1 - 2023 SN - 978-3-031-41022-2 U6 - https://doi.org/10.1007/978-3-031-41023-9_58 SN - 2195-4356 SP - 577 EP - 583 PB - Springer Nature CY - Cham, Schweiz ET - 1 ER - TY - GEN A1 - Jhanji, Avantika A1 - Sydow, Benjamin A1 - Adams, Tom-Eric A1 - Habisch, Stefan A1 - Härtel, Sebastian T1 - Influence of the Initial Microstructure on the Mechanical Behavior During Forming for Inline Manufacturing Process Routes T2 - Proceedings of the 14th International Conference on the Technology of Plasticity - Current Trends in the Technology of Plasticity, ICTP 2023 - Volume 2 N2 - With a view of sustainability and the rising energy costs currently, manufacturing processes of metals are becoming increasingly focused on optimizing process parameters such as energy and time consumption. A conventional hot-forming process route currently involves casting an ingot, letting it cool down, and heating it up again for the hot-forming process (see Fig. 1a). In order to implement the combination of casting and forging, avoiding the reheating cycle and using less energy, by utilizing the casting heat (see Fig. 1b), a methodology was developed within the present work to quantify the influence of the resulting microstructure as a function of the cooling rate on the forming and recrystallization behavior (see Fig. 1c). For this purpose, AISI 301 austenitic stainless-steel cast samples with different cast cooling rates were generated. An in-situ high-temperature microscope is used to determine the holding time and the heating rate. Dilatometer tests are performed to characterize the interaction between initial microstructure and the flow curves to verify the determination method (see Fig. 1d). The aim was to demonstrate whether the microstructure evolution and mechanical behavior is affected by the initial microstructure. The flow curves and the post-forming microstructure show a higher degree of recrystallization in fast-cooled microstructure than slow-cooled microstructure. Hence, it was found that the initial microstructure and the associated temperature history does have an impact on the mechanical properties. Y1 - 2023 SN - 978-3-031-40919-6 SN - 978-3-031-40920-2 U6 - https://doi.org/10.1007/978-3-031-40920-2_53 SN - 2195-4356 SP - 513 EP - 524 PB - Springer Nature Switzerland CY - Cham ER - TY - GEN A1 - Graf, Marcel A1 - Pippig, Robert A1 - Lehnert, Tim A1 - Jedynak, Angelika A1 - Härtel, Sebastian ED - Mocellin, Katia T1 - Aluminium-Matrix-Composites (AMC) for Hot Forged Components T2 - Proceedings of the 14th International Conference on the Technology of Plasticity - Current Trends in the Technology of Plasticity, ICTP 2023 - Volume 1 N2 - The development of new materials or material systems is always accompanied by the development of processing technologies suitable for the material. The reduction of process steps, the saving of material and the optimization of material properties are aims of forming processes. The basis for this is the comprehensive characterisation of the thermos-physical and thermos-mechanical technologically relevant material behaviour, taking into account the real process conditions. In the present work, the material-specific process limits were determined by means of experimental simulation and used in the numerical simulation in order, on the one hand, to identify the forming steps for optimizing the manufacturing conditions and, on the other hand, to be able to set the final material properties. It was essential to homogenize the casting microstructure for the forming processes and to adjust it to globulitical grains by solution annealing. The previously limited forming behaviour of the cast AlSi9Mg alloy with 20 vol.-% SiC could be increased thus to forging-relevant plastic strains without occurring damages. Based on the comprehensive temperature-dependent material data, a one-step and resource-efficient manufacturing process for AMC materials by hot forming could be developed with the help of the FE software Simufact Forming and validated in reality under near-industrial conditions. Y1 - 2023 SN - 978-3-031-41022-2 SN - 978-3-031-41023-9 U6 - https://doi.org/10.1007/978-3-031-41023-9_4 SN - 2195-4356 SP - 36 EP - 47 PB - Springer Nature Switzerland CY - Cham ER - TY - GEN A1 - Buhl, Johannes A1 - Härtel, Sebastian A1 - Besong, Lemopi Isidore ED - Mocellin, Katia T1 - Temperature Control of the Two-Point Incremental Forming Process to Achieve Homogeneous Martensite Content Based on Finite Element Simulations T2 - Proceedings of the 14th International Conference on the Technology of Plasticity - Current Trends in the Technology of Plasticity, ICTP 2023 - Volume 1 N2 - Deformation-induced martensite has been observed in the incremental sheet forming of metastable austenitic stainless steels (MASS). The presence of martensite improves the characteristics of the springs. Martensite transformation usually occurs at low temperatures (<70 ℃). Depending on the tool speed, incremental forming of disk springs requires between 3 to 5 min. The forming time needs to be short to increase the process output in industrial settings. However, accelerating the process leads to high temperatures above the martensite transformation temperature that suppress martensite formation, necessitating temperature control during forming. It is suggested to enhance the martensite content of the blank by cooling during the forming operation. In this contribution, two-point incremental sheet forming is conducted to determine the influence of process temperature on the phase content of MASS disk springs. A temperature-dependent phase change material model that includes the strain rate effect is implemented in finite element (FE) simulations to predict the martensite content. FE simulations are performed to investigate the convection coefficients and cooling time leading to process temperatures below 70 ℃. The framework can be used to control and speed up the incremental forming of disk springs while maintaining a high martensite content. Y1 - 2023 SN - 978-3-031-41022-2 SN - 978-3-031-41023-9 U6 - https://doi.org/10.1007/978-3-031-41023-9_74 SN - 2195-4356 SP - 739 EP - 747 PB - Springer CY - Cham ER - TY - GEN A1 - Hussain, G. A1 - Hassan, Malik A1 - Wei, Hongyu A1 - Buhl, Johannes A1 - Xiao, Maohua A1 - Iqbal, Asif A1 - Qayyum, Hamza A1 - Riaz, Asim Ahmed A1 - Muhammad, Riaz A1 - Ostrikov, Kostya T1 - Advances on Incremental forming of composite materials T2 - Alexandria Engineering Journal Y1 - 2023 U6 - https://doi.org/10.1016/j.aej.2023.07.045 SN - 1110-0168 VL - Vol. 79 SP - 308 EP - 336 ER - TY - GEN A1 - Hart-Rawung, Thawin A1 - Horn, Alexander A1 - Buhl, Johannes A1 - Bambach, Markus A1 - Merklein, Marion T1 - A unified model for isothermal and non-isothermal phase transformation in hot stamping of 22MnB5 steel T2 - Journal of Materials Processing Technology Y1 - 2023 U6 - https://doi.org/10.1016/j.jmatprotec.2023.117856 SN - 1873-4774 SN - 0924-0136 VL - 313 ER - TY - CHAP A1 - Israr, Rameez A1 - Buhl, Johannes ED - Khan, Wasim Ahmed T1 - An Introduction to Additive Manufacturing (AM) of Metals and Its Trends in Wire-Arc Additive Manufacturing (WAAM) Simulations T2 - Machine Tools : An Industry 4.0 Perspective Y1 - 2023 U6 - https://doi.org/10.1201/9781003220985 PB - CRC Press CY - Boca Raton ER - TY - GEN A1 - Szyndler, Joanna A1 - Härtel, Sebastian A1 - Bambach, Markus T1 - Machine learning of the dynamics of strain hardening based on contact transformations T2 - Journal of Intelligent Manufacturing N2 - Dislocation density-based models offer a physically grounded approach to modeling strain hardening in metal forming. Since these models are typically defined by Ordinary Differential Equations (ODEs), their accuracy is constrained by both, the model formulation and the parameter identification process. Machine Learning (ML) provides an alternative by allowing models to be constructed directly from experimental data, bypassing the accuracy limitations of explicitly defined models. However, applying ML to ODEs introduces the need for novel training techniques. This work presents a new approach for developing neural ODE models for flow curve description, utilizing a contact transformation to simplify the problem of learning an ODE into a learning a multivariate function. Y1 - 2025 UR - https://link.springer.com/article/10.1007/s10845-025-02577-6 U6 - https://doi.org/10.1007/s10845-025-02577-6 VL - 2025 PB - Springer ER - TY - RPRT A1 - Schmidt, Alexander T1 - Verfahren zur Herstellung von funktional gradierten Multimaterial-Werkstoffen und Bauteile aus funktional gradierten Multimaterial-Werkstoffen N2 - Die vorliegende Erfindung betrifft ein Verfahren zur Herstellung funktional gradierter Multimaterial-Werkstoffe mittels eines additiven Fertigungsprozesses, bei welchem man nacheinander die folgenden Schritte durchführt, nämlich a) Bereitstellen einer Basis aus einem ersten Werkstoff, b) Aufbringen einer Schicht eines weiteren Werkstoffs auf der in Schritt a) bereitgestellten Basis, c) Schmelzen der in Schritt b) aufgebrachten Schicht des weiteren Werkstoffs unter Ausbildung eines additiv gefertigten Werkstoffs, d) Wiederaufschmelzen einer gewünschten Schichtdicke des in Schritt c) additiv gefertigten Werkstoffs, e) Aufbringen einer weiteren Schicht eines weiteren Werkstoffs auf die Oberfläche des in Schritt d) erhaltenen Werkstoffs, f) Schmelzen der in Schritt e) aufgebrachten Schicht unter Ausbildung eines additiv gefertigten Werkstoffs, g) Wiederaufschmelzen einer gewünschten Schichtdicke des in Schritt f) additiv gefertigten Werkstoffs unter Ausbildung eines funktional gradierten Multimaterial-Werkstoffs. Weiterhin betrifft die vorliegende Erfindung einen mittels des erfindungsgemäßen Verfahrens hergestellten funktional gradierten Multimaterial-Werkstoff und aus diesem Werkstoff hergestellte Bauteile. KW - Functionally graded materials (FGM), Multi Material Additive Manufacturing (MMAM), Laser Powder Bed Fusion (L-PBF), Laser Remelting (LR) Y1 - 2024 UR - https://depatisnet.dpma.de/DepatisNet/depatisnet?action=pdf&docid=DE102022131122A1&xxxfull=1 N1 - Bei der Publikation handelt es sich um eine Offenlegungsschrift SP - 1 EP - 18 ER - TY - GEN A1 - Kaars, Jonny A1 - Dittrich, Fabian A1 - Mayr, Peter A1 - Hensel, Jonas T1 - Welding of 42SiCr treated by quenching and partitioning : mechanical properties of the HAZ and preheating proposal T2 - Welding in the world : the international journal of materials joining N2 - A 42SiCr experimental steel was heat-treated by the quenching and partitioning (Q&P) heat treatment to achieve a combination of high strength and ductility. The associated microstructure is characterized in literature by finely distributed martensite laths with a small volume fraction of retained austenite embedded. The goal of this work is to provide a comprehensive characterization of the mechanical properties of all subzones in the heat-affected zone (HAZ) of welded 42SiCr-Q&P steel. Dedicated microspecimens were subjected to a specifically selected thermal cycle in a dilatometer and characterized by mechanical testing and microstructural assessment. One specimen series is dedicated to the assessment of the mechanical properties of the material after welding; another four specimen series represent some carefully selected strategies to mitigate adverse effects of welding. Tensile testing revealed a decrease in yield strength in the HAZ by up to 35%. The ductility of the material showed inverse behavior. Material in the supercritical zone shows > 2000 MPa of ultimate strength, but at the same time is very brittle. The most remarkable result showed that the embrittlement in the supercritical zone can be successfully mitigated by holding the material at temperatures in the range of 200–250 °C for 5 min upon cooling, resulting in a yield strength of around 1400 MPa along with a ductility of > 10%, restoring the desired property combination. This very promising observation suggests fusion welding of 42SiCr-Q&P might be possible by means of preheating, maintaining the superior mechanical properties of Q&P in the weld. KW - Quenching and partitioning KW - 42SiCr KW - HAZ KW - Welding KW - Tensile strength KW - Fracture strain KW - Hardness Y1 - 2025 U6 - https://doi.org/10.1007/s40194-025-02032-3 SP - 1 EP - 13 PB - Springer CY - Berlin ER - TY - CHAP A1 - Grüger, Lennart A1 - Fischer, Tim Sebastian A1 - Korb, Elisa A1 - Härtel, Sebastian ED - Jochem, Roland ED - Maurice, Meyer T1 - Vergleichende Prozesskettenuntersuchung der konventionellen und additiven Fertigung eines Demonstratorbauteils unter umwelttechnischen Aspekten T2 - Rethinking Quality - Wandel des Qualitätsmanagements durch Digitalisierung und Künstliche Intelligenz : Bericht zur GQW-Jahrestagung 2024 in Berlin N2 - Nachhaltigkeit ist branchenübergreifend ein relevantes Thema. Häufig werden zu umwelttechnischen Untersuchungen jedoch nur einzelne Schritte der Fertigung eines Produktes und nicht die gesamte Prozesskette betrachtet. Der vorliegende Artikel liefert einen Vergleich von konventionellen und additiven Fertigungsverfahren anhand eines Demonstratorbauteils unter umwelttechnischen Gesichtspunkten. Zu diesem Zweck werden die Wertschöpfungsketten der additiven Fertigungsverfahren des Laser Powder Bed Fusion und der Wire Arc Direct Energy Deposition mit einer konventionellen Fertigungsprozesskette verglichen. Hierbei kommen Energieverbrauch, CO2-Ausstoß und Abfallaufkommen als wesentliche Vergleichskriterien zur Anwendung. Im Ergebnis sind die additiven Fertigungsverfahren für das Demonstratorbauteil, in Bezug auf die genannten Kriterien als nachhaltiger zu bewerten. Der Artikel erhebt keinen Anspruch auf vollständige Übertragbarkeit, präsentiert jedoch einen Ansatz zur Analyse der Bauteilnachhaltigkeit über die gesamte Wertschöpfungskette. KW - Wertschöpfungskette KW - Nachhaltigkeit KW - Additive Fertigung Y1 - 2025 SN - 978-3-658-47212-2 SN - 978-3-658-47213-9 U6 - https://doi.org/https://doi.org/10.1007/978-3-658-47213-9_7 SP - 123 EP - 142 PB - Springer Fachmedien Wiesbaden CY - Wiesbaden ER - TY - GEN A1 - Grüger, Lennart A1 - Szyndler, Joanna A1 - Jensch, Felix A1 - Härtel, Sebastian T1 - Porosity analysis of L-PBF manufactured AZ91D components T2 - Materials research proceedings N2 - Several materials for joint replacement parts approved in medical technology are being investigated. Magnesium alloys are very suitable for implants due to the similar strength properties between magnesium alloys and human bone. Therefore, the present work aims to examine the parameters for producing the magnesium alloy AZ91D. For this purpose, 16 samples were manufactured with varying laser power and exposure speed and examined using µCT analyses. As a result, densities between 99.56 and 95.21 percent were achieved. The samples with the lowest density were subjected to a HIP process to increase the relative density. However, a further µCT analysis revealed only minor positive effects of the HIP process. An analysis of the number and size of the pores indicates that the pores bonded together instead of being closed. KW - A91D KW - Additive Manufacturing KW - L-PBF KW - HIP KW - Process Parameter Analysis Y1 - 2025 SN - 978-1-64490-359-9 U6 - https://doi.org/10.21741/9781644903599-22 SN - 2474-395X VL - 54 SP - 199 EP - 208 PB - Materials Research Forum LLC CY - Millersville, PA ER - TY - GEN A1 - Sviridov, Alexander A1 - Alimov, Artem A1 - Jensch, Felix A1 - Dubinin, Sergej A1 - Härtel, Sebastian T1 - Influence of surface quality on performance of forging dies produced by additive manufacturing the role of post-processing in LPBF-manufactured X55 steel T2 - Materials research proceedings N2 - Laser Powder Bed Fusion (LPBF) has become a key technology in additive manufacturing (AM), enabling the production of highly complex geometries and is increasingly applied in serial production. With the continuous expansion of processable materials, LPBF is now also being considered for the manufacturing of forging dies. However, LPBF application for tool steels such as H11 is limited by their susceptibility to hot cracking. Maraging steels like X55 present a promising alternative due to their superior resistance to such defects. A major advantage of this technology for forging dies lies in the potential elimination of extensive machining required to refine rough as-built surfaces, thereby streamlining and accelerating the production process. Achieving this goal requires systematic investigations into non-machining post-processing techniques for targeted surface modifications, along with a comprehensive evaluation of mechanical properties and surface integrity after post-processing. This study examines the influence of different post-processing methods on the surface quality, mechanical properties, and tribological behavior of LPBF-manufactured X55 (1.2709) specimens. To evaluate surface roughness and mechanical performance, slope specimens and tensile specimens were analyzed in different conditions: as-built, mechanically machined, sandblasted, and treated via Hirtisition®. Additionally, flat dies were produced and subjected to ring compression tests to determine friction factors under varying surface and lubrication conditions. The findings emphasize the crucial role of post-processing in optimizing the surface quality and functional performance of LPBF-manufactured forging tools, offering valuable insights for their further development. KW - Additive manufacturing KW - L-PBF KW - Forging dies KW - Hot bulk forging KW - Friction KW - X55 Y1 - 2025 SN - 978-1-64490-359-9 U6 - https://doi.org/10.21741/9781644903599-27 SN - 2474-395X VL - 54 SP - 245 EP - 253 PB - Materials Research Forum LLC CY - Millersville, PA ER - TY - GEN A1 - Okolo, Chukwuemeka A1 - Eissing, Katharina A1 - Williams, Richard A1 - Jensch, Felix A1 - Fergani, Omar A1 - Härtel, Sebastian T1 - Investigation of the influence of AI-controlled process parameter adjustment on the mechanical properties of LBPF-manufactured parts T2 - Materials research proceedings N2 - This study investigates the influence of machine learning (ML) based process parameter adjustments on the microstructure, relative density, and mechanical properties of laser powder bed fusion (LPBF)-manufactured components, focusing on AlSi10Mg and Ti6Al4V. The ML algorithm optimizes the thermal history by adjusting laser power and exposure time at the vector level, ensuring consistent cooling and solidification dynamics. Microscopy revealed a refined and homogeneous microstructure in the optimized AlSi10Mg samples, with reduced grain size (4.92 µm compared to 6.37 µm in non-optimized samples). Relative density analysis showed a significant improvement for optimized samples, achieving consistent values across top, middle, and bottom sections of the specimen. Hardness measurements confirmed the homogenized mechanical properties, with more uniform and elevated hardness values observed in optimized samples. This study demonstrates that ML-based process optimization minimizes defects like porosity and microcracks, enabling improved mechanical performance and efficient process qualification for LPBF-manufactured parts. The findings underline the potential of AI-driven solutions for addressing complex geometrical and thermal challenges in LPBF process. KW - LPBF-process KW - Machine learning KW - Mechanical properties Y1 - 2025 SN - 978-1-64490-359-9 U6 - https://doi.org/10.21741/9781644903599-24 SN - 2474-395X VL - 54 SP - 218 EP - 227 PB - Materials Research Forum LLC CY - Millersville, PA ER - TY - GEN A1 - Emdadi, Aliakbar A1 - Jensch, Felix A1 - Szyndler, Joanna A1 - Huang, Hsuan-Po A1 - Härtel, Sebastian A1 - Weiß, Sabine T1 - Void closure behavior during hot forming of an Fe-Al alloy T2 - Materials research proceedings N2 - Hot forging is a forming process that can be used as a post-processing treatment to close residual porosity and refine the microstructure of additively manufactured materials, resulting in improved mechanical properties. During hot forging, void closure occurs through plastic deformation resulting from a predominantly compressive stress state at elevated temperatures. In the present work, Fe-25Al-1.5Ta (at. %) samples have been produced by laser powder bed fusion (LPBF) using a larger layer thickness and scan speed than commonly used to achieve a target porosity fraction of approximately 10%. Full densification is attempted in the subsequent hot compression step at various height reduction ratios. The as-built LPBF samples contained 8-10% voids. After deformation to true strains of 0.2, 0.4, and 0.6, the void fraction decreased significantly to approximately 4%, 2.3%, and 1.1%, respectively. Hot compression resulted in the complete closure of large pores with a size range of 200-300 µm and a significant reduction in the size of small to medium pores. These results show potential for improving the productivity of the LPBF by speeding up the process by increasing layer thickness and scanning speed while maintaining a reasonable density. Full densification should be achieved by subsequent hot forging. KW - Hot metal forming KW - Laser powder bed fusion (LPBF) KW - Post-processing KW - Void closure KW - X-Ray micro-computed tomography Y1 - 2025 SN - 978-1-64490-359-9 U6 - https://doi.org/10.21741/9781644903599-99 SN - 2474-395X VL - 54 SP - 927 EP - 935 PB - IWA Publishing CY - Millersville, PA ER - TY - GEN A1 - Ertugrul, Gökhan A1 - Emdadi, Aliakbar A1 - Jedynak, Angelika A1 - Weiß, Sabine A1 - Härtel, Sebastian T1 - Hot forming behavior of tungsten carbide reinforced Ni-based superalloy 625 additively manufactured by laser directed energy deposition T2 - Additive manufacturing letters N2 - The demands of high-performance industries such as aerospace, automotive, tool manufacturing, oil, and gas industries are driving the innovation in high-performance materials and their production methods. This study explores the impact of hybrid manufacturing, specifically the effect of the addition of tungsten carbide (WC/W2C) via Laser-Directed Energy Deposition (L-DED), on the hot workability, hardness, and microstructure of nickel-based superalloy Inconel 625 (IN625). IN625 is known for its high temperature and high corrosion resistance, and tungsten carbide for its high wear resistance and grain refinement effect. The integration of WC/W2C particles into the IN625 matrix, in addition to the use of the hybrid approach of additive manufacturing followed by a hot–forming process, significantly influences the microstructure and mechanical behavior of the material. Thus, while incorporation of the WC/W2C can strengthen the material and extend the mechanical limitations, its full impact, including any potential usages, should be thoroughly evaluated for the intended application of the materials. To understand the effect of WC/W2C, additive manufacturing of IN625 both with and without WC/W2C and isothermal hot compression was carried out. The objective is to analyze the differences in microstructure and properties between L-DED manufactured IN625, and WC-reinforced IN625, and their hot-forming behavior, focusing on the effects of WC addition and post-deformation on microstructure and mechanical properties. This work represents the first investigation into the effect of WC/W2C hard particles on the hot-forming process of additively manufactured Ni-based metal matrix composites. Y1 - 2025 U6 - https://doi.org/10.1016/j.addlet.2025.100267 SN - 2772-3690 VL - 13 SP - 1 EP - 12 PB - Elsevier CY - Amsterdam ER -