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  - 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  - https://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  - 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  - https://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  - 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  - https://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  - https://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  - 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  - 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  - https://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  - https://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  - 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  - 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  - Rieper, Harald
A1  - Gebhardt, Andreas
A1  - Stucker, Brent
T1  - Selective Laser Melting of the Eutectic Silver-Copper Alloy Ag 28 wt % Cu
JF  - RTejournal - Forum für Rapid Technologie
N2  - The aim of this work was to perform a detailed investigation of the use of Selective Laser Melting (SLM) technology to process eutectic silver-copper alloy Ag 28 wt. % Cu (also called AgCu28). The processing occurred with a Realizer SLM 50 desktop machine. The powder analysis (SEM-topography, EDX, particle distribution) was reported as well as the absorption rates for the near-infrared (NIR) spectrum. Microscope imaging showed the surface topography of the manufactured parts. Furthermore, microsections were conducted for the analysis of porosity. The Design of Experiments approach used the response surface method in order to model the statistical relationship between laser power, spot distance and pulse time.
KW  - SLM
KW  - Response Surface Method
KW  - Porositat
KW  - Eutectic Silver Copper alloy
KW  - Additive Manufacturing
Y1  - 2016
U6  - http://nbn-resolving.de/urn/resolver.pl?nbn:de:0009-2-44141
SN  - 1614-0923
VL  - 13
ER  - 
TY  - JOUR
A1  - Roesner, Andreas
A1  - Scheik, Sven
A1  - Olowinsky, Alexander
A1  - Gillner, Arnold
A1  - Propawe, Reinhart
A1  - Schleser, Markus
A1  - Reisgen, Uwe
T1  - Innovative approach of joining hybrid components
JF  - Journal of laser applications
Y1  - 2011
SN  - 1042-346X
VL  - Vol. 23
IS  - Iss. 3
SP  - 32007
PB  - Laser Institute of America
CY  - Orlando, Fla.
ER  - 
TY  - JOUR
A1  - Roesner, Andreas
A1  - Scheik, Sven
A1  - Olowinsky, Alexander
A1  - Gillner, Arnold
A1  - Reisgen, Uwe
A1  - Schleser, Markus
T1  - Laser assisted joining of plastic metal hybrids
JF  - Lasers in manufacturing 2011 : proceedings of the sixth International WLT Conference on Lasers in Manufacturing, Munich, May 23 - 26 2011. (Physics procedia ; Vol. 12 (2011), Part B)
Y1  - 2011
SN  - 1875-3892 (E-Journal); 1875-3884 (Print)
SP  - 370
EP  - 377
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Scheidweiler, Robert
A1  - Triesch, Eberhard
T1  - A note on the duality between matchings and vertex covers in balanced hypergraphs
JF  - Journal of Combinatorial Optimization
N2  - We present a new Min-Max theorem for an optimization problem closely connected to matchings and vertex covers in balanced hypergraphs. The result generalizes Kőnig’s Theorem (Berge and Las Vergnas in Ann N Y Acad Sci 175:32–40, 1970; Fulkerson et al. in Math Progr Study 1:120–132, 1974) and Hall’s Theorem (Conforti et al. in Combinatorica 16:325–329, 1996) for balanced hypergraphs.
KW  - Hall’s Theorem
KW  - Koenig’s Theorem
KW  - Duality
KW  - Balanced hypergraph
KW  - Hypergraph
KW  - Vertex cover
KW  - Matching
Y1  - 2016
U6  - https://doi.org/10.1007/s10878-015-9887-5
SN  - 1573-2886
N1  - Lehrstuhl II für Mathematik RWTH Aachen
VL  - 32
IS  - 2
SP  - 639
EP  - 644
PB  - Springer
CY  - Berlin
ER  - 
TY  - JOUR
A1  - Schleser, Markus
A1  - Walk-Lauffer, Bernd
A1  - Raupach, Michael
A1  - Dilthey, Ulrich
T1  - Application of polymers for textile-reinforced concrete
JF  - Journal of materials in civil engineering : properties, applications, durability
Y1  - 2006
SN  - 0899-1561
VL  - 18
IS  - 5
SP  - 670
EP  - 676
ER  - 
TY  - JOUR
A1  - Schwarz, Alexander
A1  - Gebhardt, Andreas
A1  - Schleser, Markus
A1  - Popoola, Patricia
T1  - New Welding Joint Geometries Manufactured by Powder Bed Fusion from 316L
JF  - Materials Performance and Characterization 8
Y1  - 2019
U6  - https://doi.org/10.1520/MPC20180096
SN  - 2379-1365
IS  - in press
ER  - 
TY  - JOUR
A1  - Seiler, Friedrich
A1  - Pichler, Alexander
A1  - Pfaff, Raphael
A1  - Srulijes, Julio
T1  - Novel processing tools for automated doppler picture velocimetry (DPV) evaluation
JF  - Journal of visualization
Y1  - 2009
SN  - 1343-8875
VL  - Vol. 12
IS  - Iss. 4
SP  - 323
EP  - 337
ER  - 
TY  - JOUR
A1  - Starke, Günther
T1  - Welding in the century of information technology. Session 1
JF  - Welding in the World. 34 (1994), H. 9
Y1  - 1994
SN  - 0043-2288
SP  - 1
EP  - 20
ER  - 
TY  - JOUR
A1  - Starke, Günther
A1  - Drews, P.
T1  - Development approaches for advanced control in automated arc welding
Y1  - 1985
N1  - Konferenz-Einzelbericht: Automation and robotisation in welding and allied processes. International conference on automation and robotisation in welding and allied processes, Strasbourg, FR, 02.09.1985-03.09.1985
SP  - 115
EP  - 124
ER  - 
TY  - JOUR
A1  - Starke, Günther
A1  - Drews, P.
T1  - Le soudage au siecle de l'informatique
JF  - Souder. 18 (1994), H. 6
Y1  - 1994
SN  - 0246-1900
SP  - 33
EP  - 44
ER  -