TY - GEN A1 - Breuß, Michael A1 - Buhl, Johannes A1 - Mansouri Yarahmadi, Ashkan A1 - Bambach, Markus A1 - Peter, Pascal T1 - A Simple Approach to Stiffness Enhancement of a Printable Shape by Hamilton-Jacobi Skeletonization T2 - Procedia Manufacturing N2 - The 3D-Printing technology is ready to produce parts with specific properties like individual stiffness. Based on a predefined outer shape, the inner structure of a printed part defines mainly the mechanical features. By Hamilton-Jacobi skeletonization, a stiffness enhancement of a printable shape can be achieved in a way, that a novel AM-corner includes linear axis function. Originating in the field of shape analysis in computer vision and graphics, the so-called medial axis transform (MAT) is designed for the computation of a structure that resembles the bone structure of biological shapes. The input for MAT computation is typically a shape’s boundary. The arising topological skeletons have proven to provide a useful concept for many applications; however, their computation is generally intricate and also known to rely on many parameters, diminishing the accessibility of skeletonization methods. In this work, the classical Hamilton-Jacobi skeletonization approach is adopted to compute a stability enhancing shape structure. As the basic method has not been designed for the context of additive manufacturing, a set of suitable modifications are introduced to design an algorithm that suits our intended purpose. Unlike the traditional skeletonization schemes, the resulting method appears to be robust and in practice almost completely automated as we can identify useful generic parameter settings. By a finite element method (FEM) study, the elastic stress properties of the AM-corner with linear axis function is validated and printed with in metal (1.4404) with the 3D Selected Laser Melting (SLM) system AconityMIDI. The AM-knot with skeletonization guides approximately 20 times better than a standard knot. While the first obtained results are shown as 2.5 dimensional shapes, it is emphasized that the proposed algorithm offers many possibilities for extensions to three dimensions and variations in context of additive manufacturing. KW - Skeletonization KW - Hamilton-Jacobi skeletonization KW - stiffness enhancement KW - 3D printing KW - additive manufacturing Y1 - 2020 U6 - https://doi.org/10.1016/j.promfg.2020.04.147 SN - 2351-9789 N1 - 23rd International Conference on Material Forming (ESAFORM 2020) VL - Vol. 47 SP - 1190 EP - 1196 ER - TY - GEN A1 - Buhl, Johannes A1 - Hart-Rawung, Thawin A1 - Bambach, Markus T1 - Nutzung von Neuralen Netzen zur effizienten Auslegung des Presshärtens von 22MnB5 T2 - Tagungsband zum 15. Erlanger Workshop Warmblechumformung, Erlangen, den 17. November 2020 Y1 - 2020 SN - 978-3-00-066911-8 SP - 99 EP - 112 PB - Lehrstuhl für Fertigungstechnologie, Friedrich-Alexander-Universität Erlangen-Nürnberg CY - Erlangen ER - TY - GEN A1 - Blumberg, Julian A1 - Li, Zhoulong A1 - Besong, Lemopi Isidore A1 - Polte, Mitchel A1 - Buhl, Johannes A1 - Uhlmann, Eckart A1 - Bambach, Markus T1 - Deformation error compensation of industrial robots in single point incremental forming by means of data-driven stiffness model T2 - 26th International Conference on Automation and Computing (ICAC), 2-4 Sept. 2021, Portsmouth, United Kingdom Y1 - 2021 SN - 978-1-86043-557-7 SN - 978-1-6654-4352-4 U6 - https://doi.org/10.23919/ICAC50006.2021.9594138 ER - TY - GEN A1 - Bambach, Markus A1 - Imran, Muhammad A1 - Sizova, Irina A1 - Buhl, Johannes A1 - Gerster, Stephan A1 - Herty, Michael T1 - A soft sensor for property control in multi-stage hot forming based on a level set formulation of grain size evolution and machine learning T2 - Advances in Industrial and Manufacturing Engineering Y1 - 2021 U6 - https://doi.org/10.1016/j.aime.2021.100041 SN - 2666-9129 IS - 2 ER - TY - GEN A1 - Israr, Rameez A1 - Buhl, Johannes A1 - Bambach, Markus T1 - A study on power-controlled wire-arc additive manufacturing using a data-driven surrogate model T2 - The International Journal of Advanced Manufacturing Technology N2 - Wire-arc additive manufacturing (WAAM) provides an alternative for the production of various metal products needed in medium to large batch sizes due to its high deposition rates. However, the cyclic heat input in WAAM may cause local overheating. To avoid adverse effects on the performance of the part, interlayer dwelling and active cooling are used, but these measures increase the process time. Alternatively, the temperature during the WAAM process could be controlled by optimizing the welding power. The present work aims at introducing and implementing a novel temperature management approach by adjusting the weld-bead cross-section along with the welding power to reduce the heat accumulation in the WAAM process. The temperature evolution during welding of weld beads of different cross-sections is investigated and a database of the relation between optimal welding power for beads of various sizes and different pre-heating temperatures was established. The numerical results are validated experimentally with a block-shaped geometry. The results show that by the proposed method, the test shape made was welded with lower energy consumption and process time as compared to conventional constant-power WAAM. The proposed approach efficiently manages the thermal input and reduces the need for pausing the process. Hence, the defects related to heat accumulation might be reduced, and the process efficiency increased. Y1 - 2021 U6 - https://doi.org/10.1007/s00170-021-07358-y SN - 1433-3015 SN - 0268-3768 VL - 177 IS - 7-8 SP - 2133 EP - 2147 ER - TY - GEN A1 - Nguyen, Lam A1 - Buhl, Johannes A1 - Israr, Rameez A1 - Bambach, Markus T1 - Analysis and compensation of shrinkage and distortion in wire-arc additive manufacturing of thin-walled curved hollow sections T2 - Additive Manufacturing Y1 - 2021 U6 - https://doi.org/10.1016/j.addma.2021.102365 SN - 2214-8604 VL - Vol. 47 ER - TY - GEN A1 - Buhl, Johannes A1 - Klöppel, Thomas A1 - Merten, Mathias A1 - Haufe, Andre A1 - Israr, Rameez A1 - Bambach, Markus T1 - Numerical prediction of process-dependent properties of high-performance Ti6Al4 in LS-DYNA T2 - ESAFORM 2021 : 24th International Conference on Material Forming Y1 - 2021 U6 - https://doi.org/doi: 10.25518/esaform21.1496 ER - TY - GEN A1 - Maqbool, Fawad A1 - Maaß, Fabian A1 - Buhl, Johannes A1 - Hahn, Marlon A1 - Hajavifard, Ramin A1 - Walther, Frank A1 - Tekkaya, A. Erman A1 - Bambach, Markus T1 - Targeted residual stress generation in single and two point incremental sheet forming (ISF) T2 - Archive of Applied Mechanics Y1 - 2021 U6 - https://doi.org/10.1007/s00419-021-01935-z SN - 1432-0681 SN - 0939-1533 VL - 91 IS - 8 SP - 3465 EP - 3487 ER - TY - GEN A1 - Afzal, Muhammad Junaid A1 - Hajavifard, Ramin A1 - Buhl, Johannes A1 - Walther, Frank A1 - Bambach, Markus T1 - Influence of process parameters on the residual stress state and properties in disc springs made by incremental sheet forming (ISF) T2 - Forschung im Ingenieurwesen Y1 - 2021 U6 - https://doi.org/10.1007/s10010-021-00491-w SN - 1434-0860 SN - 0015-7899 VL - 85 IS - 3 SP - 783 EP - 793 ER - TY - GEN A1 - Abas, Muhammad A1 - Alkahtani, Mohammed A1 - Khalid, Qazi Salman A1 - Hussain, Ghulam A1 - Abidi, Mustufa Haider A1 - Buhl, Johannes T1 - Parametric Study and Optimization of End-Milling Operation of AISI 1522H Steel Using Definitive Screening Design and Multi-Criteria Decision-Making Approach T2 - Materials Y1 - 2022 U6 - https://doi.org/10.3390/ma15124086 SN - 1996-1944 VL - 15 IS - 12 ER - TY - GEN A1 - Besong, Lemopi Isidore A1 - Buhl, Johannes A1 - Bambach, Markus T1 - Increasing formability in hole-flanging through the use of punch rotation based on temperature and strain rate dependent forming limit curves T2 - International Journal of Material Forming Y1 - 2022 U6 - https://doi.org/10.1007/s12289-022-01684-6 SN - 1960-6214 SN - 1960-6206 VL - 15 IS - 3 SP - 1 EP - 21 ER - TY - GEN A1 - Israr, Rameez A1 - Buhl, Johannes A1 - Härtel, Sebastian A1 - Bambach, Markus T1 - Reinforcement of Tooling Using Residual Stresses Generated by Cladding by Arc Welding T2 - Metals N2 - Cladding is typically used to protect components from wear and corrosion while also improving the aesthetic value and reliability of the substrate. The cladding process induces significant residual stresses due to the temperature difference between the substrate and the clad layer. However, these residual stresses could be effectively utilized by modifying processes and geometrical parameters. This paper introduces a novel methodology for using the weld-cladding process as a cost-effective alternative to various existing reinforcement techniques. The numerical analyses are performed to maximize the reinforcement of a cylindrical tool. The investigation of how the weld cladding develops compressive stresses on the specimen in response to a change in the weld beads and the welding sequence is presented. For the benchmark shape, experimental verification of the numerical model is performed. The influence of the distance between the weld beads and the effect of the tool diameter is numerically investigated. Furthermore, the variation in compressive stresses due to temperature fluctuations during the extrusion process has been evaluated. The results showed that adequate compressive stresses are generated on the welded parts through the cladding process after cooling. More compressive stresses are induced in the tool as the cross-section of the weld bead is increased. Furthermore, keeping a gap between the adjacent beads improves tool reinforcement. Hence, the targeted reinforcement of the substrate can be achieved by optimizing the welding sequence and process parameters. KW - Additive Manufacturing (AM) KW - Wire Arc Additive Manufacturing (WAAM) KW - weld cladding KW - residual stresses KW - reinforcement KW - hole drilling method KW - LS-Dyna KW - numerical simulation Y1 - 2022 U6 - https://doi.org/10.3390/met12060984 SN - 2075-4701 VL - 12 IS - 6 ER - 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 - 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 - 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 -