TY - JOUR A1 - Reisgen, Uwe A1 - Schleser, Markus A1 - Mokrov, Oleg A1 - Zabirov, Alexander A1 - Füssel, Uwe A1 - Schnick, Michael A1 - Hertel, Martin A1 - Jaeckel, Sebastian T1 - Modellierung und Visualisierung der MSG-Lichtbogenprozesse JF - Schweissen und Schneiden : Fachzeitschrift für Schweißen und verwandte Verfahren Y1 - 2012 SN - 0036-7184 VL - 64 IS - 4 SP - 166 EP - 174 PB - DVS Verlag CY - Düsseldorf ER - TY - JOUR A1 - Reisgen, Uwe A1 - Schleser, Markus A1 - Mokrov, Oleg A1 - Zabirov, Alexander A1 - Füssel, Uwe A1 - Schnick, Michael A1 - Hertel, Martin A1 - Jaeckel, Sebastian T1 - Modelling and visualisation of the GMA process JF - Welding and Cutting Y1 - 2012 SN - 1612-3433 VL - 11 IS - 4 SP - 242 EP - 249 PB - DVS Verlag CY - Düsseldorf ER - TY - JOUR A1 - Reisgen, Uwe A1 - Schleser, Markus A1 - Mokrov, Oleg A1 - Zabirov, Alexander T1 - Virtual welding equipment for simulation of GMAW processes with integration of power source regulation JF - Frontiers of materials science Y1 - 2011 SN - 2095-0268 (E-Journal); 2095-025X (Print) VL - Vol. 5 IS - Iss. 2 SP - 79 EP - 89 PB - Springer CY - Berlin ER - TY - JOUR A1 - Reisgen, Uwe A1 - Schleser, Markus A1 - Mokrov, Oleg A1 - Ahmed, Essam T1 - Statistical modeling of laser welding of DP/TRIP steel sheets JF - Optics and laser technology N2 - In this research work, a statistical analysis of the CO2 laser beam welding of dual phase (DP600)/transformation induced plasticity (TRIP700) steel sheets was done using response surface methodology. The analysis considered the effect of laser power (2–2.2 kW), welding speed (40–50 mm/s) and focus position (−1 to 0 mm) on the heat input, the weld bead geometry, uniaxial tensile strength, formability limited dome height and welding operation cost. The experimental design was based on Box–Behnken design using linear and quadratic polynomial equations for predicting the mathematical models. The results indicate that the proposed models predict the responses adequately within the limits of welding parameters being used and the welding speed is the most significant parameter during the welding process. Y1 - 2012 U6 - http://dx.doi.org/10.1016/j.optlastec.2011.05.025 SN - 1879-2545 (E-Journal); 0030-3992 (Print); 0308-4280 (Print) VL - 44 IS - 1 SP - 92 EP - 101 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Reisgen, Uwe A1 - Schleser, Markus A1 - Mokrov, Oleg A1 - Ahmed, Essam T1 - Optimization of laser welding of DP/TRIP steel sheets using statistical approach JF - Optics and laser technology N2 - Generally, the quality of a weld joint is directly influenced by the welding input parameter settings. Selection of proper process parameters is important to obtain the desired weld bead profile and quality. In this research work, numerical and graphical optimization techniques of the CO2 laser beam welding of dual phase (DP600)/transformation induced plasticity (TRIP700) steel sheets were carried out using response surface methodology (RSM) based on Box–Behnken design. The procedure was established to improve the weld quality, increase the productivity and minimize the total operation cost by considering the welding parameters range of laser power (2–2.2 kW), welding speed (40–50 mm/s) and focus position (−1 to 0 mm). It was found that, RSM can be considered as a powerful tool in experimental welding optimization, even when the experimenter does not have a model for the process. Strong, efficient and low cost weld joints could be achieved using the optimum welding conditions. Y1 - 2012 U6 - http://dx.doi.org/10.1016/j.optlastec.2011.06.028 SN - 1879-2545 (E-Journal); 0030-3992 (Print); 0308-4280 (Print) VL - 44 IS - 1 SP - 255 EP - 262 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Reisgen, Uwe A1 - Schleser, Markus A1 - Mokrov, Oleg A1 - Ahmed, Essam T1 - Numerical and experimental investigation of tensile behavior of laser beam welded TRIP700 steel JF - ISIJ international Y1 - 2011 SN - 1347-5460 (E-Journal); 0915-1559 (Print) VL - Vol. 51 IS - No. 3 SP - 429 EP - 434 PB - ISIJ CY - Tōkyō ER - TY - JOUR A1 - Reisgen, Uwe A1 - Schleser, Markus A1 - Mokrov, Oleg A1 - Ahmed, Essam T1 - Uni- and bi-axial deformation behavior of laser welded advanced high strength steel sheets JF - Journal of materials processing technology N2 - Bead-on-plate butt joints of 2.5 mm hot rolled DP600/DP600 and 1.2 mm cold rolled TRIP700/TRIP700 steel sheets were performed using 6 kW CO2 laser beam welding. The welding speed ranged from 1.5 to 3.0 and from 2.1 to 3.9 m/min in DP/DP and TRIP/TRIP steel weldments respectively. A top surface helium gas was used as a shielding gas at a flow rate of 20 l/min. Metallographic examinations and transverse tensile testing (DIN EN 895: 1995) were carried out to characterize the weldments. The formability of base metals and weldments were investigated by standard Erichsen test (DIN EN ISO 20482). It was found that the uniaxial plastic behavior of both DP600 and TRIP700 base metals was in agreement with Swift and modified Mecking–Kocks models respectively. In a perpendicular tensile test to the weld line, all specimens were fractured at the base metal however the strengths were somewhat higher than those of base metal. There was a significant reduction in formability caused by welding of both DP/DP and TRIP/TRIP steel weldments and the formability has been improved with the increase of the welding speed. Y1 - 2010 U6 - http://dx.doi.org/http10.1016/j.jmatprotec.2010.08.003 SN - 0924-0136 VL - 210 IS - 15 SP - 2188 EP - 2196 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Reisgen, Uwe A1 - Schleser, Markus A1 - Mokrov, Oleg A1 - Ahmed, Essam T1 - Shielding gas influences on laser weldability of tailored blanks of advanced automotive steels JF - Applied surface science N2 - The effects of shielding gas types and flow rates on CO2 laser weldability of DP600/TRIP700 steel sheets were studied in this work. The evaluated shielding gases were helium (He), argon (Ar) and different mixtures of He and Ar. Weld penetration, tensile strength and formability (Erichsen test) of laser welds were found to be strongly dependent upon the shielding gas types. The ability of shielding gas in removing plasma plume and thus increasing weld penetration is believed to be closely related to ionization potential and atomic weight which determine the period of plasma formation and disappearance. It was found that the higher helium shielding gas flow rate, the deeper weld penetration and the lower weld width. Y1 - 2010 U6 - http://dx.doi.org/10.1016/j.apsusc.2010.08.042 SN - 0169-4332 (E-Journal); 0169-4332 (Print) VL - 257 IS - 5 SP - 1401 EP - 1406 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Reisgen, Uwe A1 - Schleser, Markus A1 - Jerabek, Jakub A1 - Chudoba, Rostislav T1 - Messung der Strahlqualität einer Elektronenstrahlanlage in Umgebungsatmosphäre JF - Materialwissenschaft und Werkstofftechnik N2 - In den letzten Jahrzehnten hat das Elektronenstrahlschweißen, das bereits im größeren Maßstab verwendet wird, seine Fähigkeit als qualitatives Werkzeug für die Verbindung verschiedener Materialen nachgewiesen. Das Non Vacuum Electron Beam Welding (NV-EBW) hat zahlreiche Vorteile im Vergleich zum Elektronenstrahlschweißen im Vakuum, da man unter normalem Atmosphärendruck arbeiten kann. Im Hinblick auf die reproduzierbare Qualität, insbesondere im Bereich der Massen-Fertigung, ist die Kontrolle der Strahlparameter sowie deren Einfluss auf das Schweißergebnis von großer Bedeutung. Durch eine genaue Kenntnis der Strahlkenngrößen wie des Strahldurchmessers und der Leistungsdichteverteilung kann eine Aussage über die sich ausbildende Schweißnaht sowie die Schweißbaddynamik getroffen werden. Messungen der Strahlkenngrößen im Prozess erlauben insbesondere die Untersuchung von Humping-Effekten. In diesem Beitrag wird der Prozess der Elektronenstrahlvermessung unter atmosphärischen Bedingungen beschrieben. Es wird zudem die Abhängigkeit der Elektronenstrahlcharakteristika von den verschiedenen Prozessparametern dargestellt. Y1 - 2010 SN - 1521-4052 VL - 41 IS - 1 SP - 45 EP - 52 PB - Wiley-VCH CY - Weinheim ER - TY - JOUR A1 - Reisgen, Uwe A1 - Schleser, Markus A1 - Harms, Alexander A1 - Schiebahn, Alexander A1 - Thiele, Regina ED - Kampker, Achim T1 - Elektromobilität - Herausforderungen an die Fügetechnik JF - mobilität morgen - Magazin zu Mobilität und Elektromobilität Y1 - 2011 VL - Jg. 1 IS - Nr. 2 SP - 16 EP - 17 ER - TY - JOUR A1 - Reisgen, Uwe A1 - Schleser, Markus A1 - Harms, Alexander A1 - Schiebahn, Alexander A1 - Naumov, Andreas T1 - Erweiterung des Parameterfelds zum Rührreibschweißen mittels konduktiver Unterstützung JF - Schweissen und Schneiden : Fachzeitschrift für Schweißen und verwandte Verfahren Y1 - 2011 SN - 0036-7184 VL - Bd. 63 IS - H. 12 SP - 710 EP - 714 PB - DVS-Media GmbH CY - Düsseldorf ER - TY - JOUR A1 - Reisgen, Uwe A1 - Schleser, Markus A1 - Feldmann, Martin A1 - Pak, Daniel A1 - Geßler, Achim T1 - Kleben dünnwandiger Bauteile aus textilbewehrtem Beton JF - Schweissen und Schneiden : Fachzeitschrift für Schweißen und verwandte Verfahren Y1 - 2008 SN - 0036-7184 VL - Bd. 60 IS - H. 7/8 SP - 408 EP - 412 ER - TY - JOUR A1 - Reisgen, Uwe A1 - Schleser, Markus A1 - Abdurakhmanov, Aydemir A1 - Gumenyuk, Andrey T1 - Measuring of plasma properties induced by non-vacuum electron beam welding JF - Physics of plasma N2 - Electron beam plasma measurement was realised by means of DIABEAM system invented by ISF RWTH Aachen. The Langmuir probe method is used for measurement. The relative simplicity of the method and the possibility of dispersion of high power on the probe allow its application for the investigation of high-power electron beams. The key element of the method is a rotating thin tungsten wire, which intersects the beam transversely on its axis and collects part of the current by itself. The signals, which are registered in the DIABEAM as a voltage, were taken in the form of amplitude. The conversion of the probe current into the distribution along the beam radius was realised using the Abel’s method. A voltage-current characteristic was built for the beam current. The local electron density as well as the electron temperature, the floating potential and the plasma potential were measured and calculated by means of this characteristic. Y1 - 2012 U6 - http://dx.doi.org/10.1063/1.3675874 SN - 1089-7674 (E-Journal); 1070-664X (Print) VL - 19 IS - 1 SP - 1 EP - 7 PB - AIP Publishing CY - Melville, NY ER - TY - JOUR A1 - Reisgen, Uwe A1 - Olschok, Simon A1 - Jakobs, Stefan A1 - Schleser, Markus A1 - Mokrov, Oleg A1 - Rossiter, Eduardo T1 - Laser beam submerged arc hybrid welding JF - Physics procedia N2 - The laser beam-submerged arc hybrid welding method originates from the knowledge that, with increasing penetration depth, the laser beam process has a tendency to pore formation in the lower weld regions. The coupling with the energy-efficient submerged-arc process improves degassing and reduces the tendency to pore formation. The high deposition rate of the SA process in combination with the laser beam process offers, providing the appropriate choice of weld preparation, the possibility of welding plates with a thickness larger than 20° mm in a single pass, and also of welding thicker plates with the double-sided single pass technique. Y1 - 2012 U6 - http://dx.doi.org/10.1016/j.phpro.2012.10.016 SN - 1875-3892 N1 - Part of special issue "Laser assisted net shape engineering 7 (LANE 2012)" VL - 39 SP - 75 EP - 83 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Reichert, Walter T1 - Berufseinstieg für Wirtschaftsingenieure - Bachelor oder Master? JF - Berufsstart Y1 - 2017 ER - TY - JOUR A1 - Ramazani, Ali A1 - Li, Yang A1 - Mukherjee, Krishnendu A1 - Prahl, Ulrich A1 - Bleck, Wolfgang A1 - Abdurakhmanov, Aydemir A1 - Schleser, Markus A1 - Reisgen, Uwe T1 - Microstructure evolution simulation in hot rolled DP600 steel during gas metal arc welding JF - Computational materials science Y1 - 2013 SN - 1879-0801 (E-Book); 0927-0256 (Print) VL - Vol. 68 SP - 107 EP - 116 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Raffeis, Iris A1 - Adjei-Kyeremeh, Frank A1 - Vroomen, Uwe A1 - Westhoff, Elmar A1 - Bremen, Sebastian A1 - Hohoi, Alexandru A1 - Bührig-Polaczek, Andreas T1 - Qualification of a Ni-Cu alloy for the laser powder bed fusion process (LPBF): Its microstructure and mechanical properties JF - Applied Sciences N2 - As researchers continue to seek the expansion of the material base for additive manufacturing, there is a need to focus attention on the Ni–Cu group of alloys which conventionally has wide industrial applications. In this work, the G-NiCu30Nb casting alloy, a variant of the Monel family of alloys with Nb and high Si content is, for the first time, processed via the laser powder bed fusion process (LPBF). Being novel to the LPBF processes, optimum LPBF parameters were determined, and hardness and tensile tests were performed in as-built conditions and after heat treatment at 1000 °C. Microstructures of the as-cast and the as-built condition were compared. Highly dense samples (99.8% density) were achieved after varying hatch distance (80 µm and 140 µm) with scanning speed (550 mm/s–1500 mm/s). There was no significant difference in microhardness between varied hatch distance print sets. Microhardness of the as-built condition (247 HV0.2) exceeded the as-cast microhardness (179 HV0.2.). Tensile specimens built in vertical (V) and horizontal (H) orientations revealed degrees of anisotropy and were superior to conventionally reported figures. Post heat treatment increased ductility from 20% to 31% (V), as well as from 16% to 25% (H), while ultimate tensile strength (UTS) and yield strength (YS) were considerably reduced. Y1 - 2020 U6 - http://dx.doi.org/10.3390/app10103401 SN - 2076-3417 N1 - Special Issue Materials Development by Additive Manufacturing Techniques VL - 10 IS - Art. 3401 SP - 1 EP - 15 PB - MDPI CY - Basel ER - TY - JOUR A1 - Raatschen, Hans-Jürgen A1 - Holzner, M. A1 - Borrmann, M. A1 - Pfrang, W. T1 - Numerische Simulation von Umformprozessen mit dem expliziten FE-Programm UFO-3D Y1 - 1991 N1 - Konferenz-Einzelbericht : FEM '91, International FEM-Congress, IKO Software Service, Baden Baden, D, 18.-19.11.1991 SP - 91 EP - 105 ER - TY - JOUR A1 - Raatschen, Hans-Jürgen T1 - Fokussierung von Spannungswellen in einer krummlinig berandeten Scheibe JF - ZAMM : Zeitschrift für Angewandte Mathematik und Mechanik Y1 - 1987 SN - 1521-4001 N1 - Artikel umfasst die Seiten 11 und 12 des 30-Seiten-langen PDFs der Online-Ausgabe. VL - 67 IS - 4 SP - T230 EP - T231 ER - TY - JOUR A1 - Raatschen, Hans-Jürgen T1 - Ingenieurstudium Hundert Jahre : von der Königlichen Höheren Maschinenbauschule Aachen zu den Ingenieurfachbereichen der Fachhochschule JF - Fachblatt Y1 - 2003 VL - 2003 IS - 1 SP - 28 EP - 29 ER -