@article{WilbringEnningPfaffetal.2020, author = {Wilbring, Daniela and Enning, Manfred and Pfaff, Raphael and Schmidt, Bernd}, title = {Neue Perspektiven f{\"u}r die Bahn in der Produktions- und Distributionslogistik durch Prozessautomation}, series = {ETR - Eisenbahntechnische Rundschau}, volume = {69}, journal = {ETR - Eisenbahntechnische Rundschau}, number = {3}, issn = {0013-2845}, pages = {15 -- 19}, year = {2020}, language = {de} } @article{EngemannDuKallweitetal.2020, author = {Engemann, Heiko and Du, Shengzhi and Kallweit, Stephan and C{\"o}nen, Patrick and Dawar, Harshal}, title = {OMNIVIL - an autonomous mobile manipulator for flexible production}, series = {Sensors}, volume = {20}, journal = {Sensors}, number = {24, art. no. 7249}, publisher = {MDPI}, address = {Basel}, isbn = {1424-8220}, doi = {10.3390/s20247249}, pages = {1 -- 30}, year = {2020}, language = {en} } @article{WingensMayPfaff2019, author = {Wingens, Niklas and May, J{\"o}rg and Pfaff, Raphael}, title = {Betrieblich-technische Innovationsans{\"a}tze zur Bremsprobe nach einer Prozess{\"a}nderung}, series = {Eisenbahntechnische Rundschau : ETR ; Zeitschrift f{\"u}r die gesamte Eisenbahntechnik}, journal = {Eisenbahntechnische Rundschau : ETR ; Zeitschrift f{\"u}r die gesamte Eisenbahntechnik}, number = {5}, publisher = {DVV Media Group}, address = {Hamburg}, issn = {0013-2845}, pages = {5}, year = {2019}, language = {de} } @article{BucurLazarescuPopetal.2019, author = {Bucur, Alexandru and Lazarescu, Lucian and Pop, Grigore Marian and Achimas, Gheorghe and Gebhardt, Andreas}, title = {Tribological performance of biodegradable lubricants under different surface roughness of tools}, series = {Academic Journal of Manufacturing Engineering}, volume = {17}, journal = {Academic Journal of Manufacturing Engineering}, number = {1}, issn = {1583-7904}, pages = {172 -- 178}, year = {2019}, language = {en} } @article{PancContiuBocanetetal.2019, author = {Panc, Nicolae and Contiu, Glad and Bocanet, Vlad and Thurn, Laura and Sabau, Emilia}, title = {The influence of cutting technology on surface wear hardness}, series = {Academic Journal of Manufacturing Engineering}, volume = {17}, journal = {Academic Journal of Manufacturing Engineering}, number = {3}, issn = {1583-7904}, pages = {205 -- 210}, year = {2019}, language = {en} } @article{WilbringEnning2019, author = {Wilbring, Daniela and Enning, Manfred}, title = {Stromversorgung auf G{\"u}terwagen - Aktuelle Bem{\"u}hungen zur Standardisierung}, series = {ETR - Eisenbahntechnische Rundschau}, volume = {68}, journal = {ETR - Eisenbahntechnische Rundschau}, number = {11}, publisher = {DVV Media Group}, address = {Hamburg}, issn = {0013-2845}, pages = {64 -- 67}, year = {2019}, language = {de} } @article{KunkelGebhardtMpofuetal.2019, author = {Kunkel, Maximilian Hugo and Gebhardt, Andreas and Mpofu, Khumbulani and Kallweit, Stephan}, title = {Quality assurance in metal powder bed fusion via deep-learning-based image classification}, series = {Rapid Prototyping Journal}, volume = {26}, journal = {Rapid Prototyping Journal}, number = {2}, issn = {1355-2546}, doi = {10.1108/RPJ-03-2019-0066}, pages = {259 -- 266}, year = {2019}, language = {en} } @article{SchwarzGebhardtSchleseretal.2019, author = {Schwarz, Alexander and Gebhardt, Andreas and Schleser, Markus and Popoola, Patricia}, title = {New Welding Joint Geometries Manufactured by Powder Bed Fusion from 316L}, series = {Materials Performance and Characterization 8}, journal = {Materials Performance and Characterization 8}, number = {in press}, issn = {2379-1365}, doi = {10.1520/MPC20180096}, year = {2019}, language = {en} } @article{Thomas2019, author = {Thomas, Axel}, title = {Die Wiederbelebung der Mitarbeiterwohnungsidee bei kommunalen Unternehmen}, series = {VM Verwaltung und Management}, volume = {25}, journal = {VM Verwaltung und Management}, number = {6}, publisher = {Nomos-Verl.-Ges.}, address = {Baden-Baden}, issn = {0947-9856}, doi = {10.5771/0947-9856-2019-6-286}, pages = {286 -- 291}, year = {2019}, language = {de} } @article{Wollert2018, author = {Wollert, J{\"o}rg}, title = {Echtzeit-Ethernet - Basis f{\"u}r Industrie 4.0}, series = {Design \& Elektronik}, journal = {Design \& Elektronik}, publisher = {WEKA-Fachmedien}, address = {M{\"u}nchen}, isbn = {0933-8667}, year = {2018}, language = {de} } @article{Wollert2018, author = {Wollert, J{\"o}rg}, title = {TSN - Schluss mit dem Feldbuskrieg?}, series = {Design \& Elektronik}, journal = {Design \& Elektronik}, number = {3}, publisher = {WEKA-Fachmedien}, address = {M{\"u}nchen}, issn = {0933-8667}, pages = {26 -- 31}, year = {2018}, language = {de} } @article{MichauxMatternKallweit2018, author = {Michaux, F. and Mattern, P. and Kallweit, Stephan}, title = {RoboPIV: how robotics enable PIV on a large industrial scale}, series = {Measurement Science and Technology}, volume = {29}, journal = {Measurement Science and Technology}, number = {7}, publisher = {IOP}, address = {Bristol}, issn = {1361-6501}, doi = {10.1088/1361-6501/aab5c1}, pages = {074009}, year = {2018}, abstract = {This work demonstrates how the interaction between particle image velocimetry (PIV) and robotics can massively increase measurement efficiency. The interdisciplinary approach is shown using the complex example of an automated, large scale, industrial environment: a typical automotive wind tunnel application. Both the high degree of flexibility in choosing the measurement region and the complete automation of stereo PIV measurements are presented. The setup consists of a combination of three robots, individually used as a 6D traversing unit for the laser illumination system as well as for each of the two cameras. Synchronised movements in the same reference frame are realised through a master-slave setup with a single interface to the user. By integrating the interface into the standard wind tunnel management system, a single measurement plane or a predefined sequence of several planes can be requested through a single trigger event, providing the resulting vector fields within minutes. In this paper, a brief overview on the demands of large scale industrial PIV and the existing solutions is given. Afterwards, the concept of RoboPIV is introduced as a new approach. In a first step, the usability of a selection of commercially available robot arms is analysed. The challenges of pose uncertainty and importance of absolute accuracy are demonstrated through comparative measurements, explaining the individual pros and cons of the analysed systems. Subsequently, the advantage of integrating RoboPIV directly into the existing wind tunnel management system is shown on basis of a typical measurement sequence. In a final step, a practical measurement procedure, including post-processing, is given by using real data and results. Ultimately, the benefits of high automation are demonstrated, leading to a drastic reduction in necessary measurement time compared to non-automated systems, thus massively increasing the efficiency of PIV measurements.}, language = {en} } @article{KunkelGebhardtMpofuetal.2018, author = {Kunkel, Maximilian Hugo and Gebhardt, Andreas and Mpofu, Khumbaulani and Kallweit, Stephan}, title = {Statistical assessment of mechanical properties of selective laser melted specimens of stainless steel}, series = {The International Journal of Advanced Manufacturing Technology}, volume = {98}, journal = {The International Journal of Advanced Manufacturing Technology}, number = {5-8}, publisher = {Springer}, address = {London}, issn = {0268-3768}, doi = {10.1007/s00170-018-2040-8}, pages = {1409 -- 1431}, year = {2018}, abstract = {The rail business is challenged by long product life cycles and a broad spectrum of assembly groups and single parts. When spare part obsolescence occurs, quick solutions are needed. A reproduction of obsolete parts is often connected to long waiting times and minimum lot quantities that need to be purchased and stored. Spare part storage is therefore challenged by growing stocks, bound capital and issues of part ageing. A possible solution could be a virtual storage of spare parts which will be 3D printed through additive manufacturing technologies in case of sudden demand. As mechanical properties of additive manufactured parts are neither guaranteed by machine manufacturers nor by service providers, the utilization of this relatively young technology is impeded and research is required to address these issues. This paper presents an examination of mechanical properties of specimens manufactured from stainless steel through the selective laser melting (SLM) process. The specimens were produced in multiple batches. This paper interrogates the question if the test results follow a normal distribution pattern and if mechanical property predictions can be made. The results will be put opposite existing threshold values provided as the industrial standard. Furthermore, probability predictions will be made in order to examine the potential of the SLM process to maintain state-of-the-art mechanical property requirements.}, language = {en} } @article{KampkerSchleserTriebsetal.2018, author = {Kampker, Achim and Schleser, Markus and Triebs, Johannes and Berg, Alexander-Karl and Hansen, Jan Ole and Fiedler, Falko}, title = {Bauteilintegrierte Vorrichtungsfunktionen im Karosseriebau : Aktuelle Ergebnisse im Forschungsprojekt ProeK}, series = {ZWF Zeitschrift f{\"u}r wirtschaftlichen Fabrikbetrieb}, volume = {113}, journal = {ZWF Zeitschrift f{\"u}r wirtschaftlichen Fabrikbetrieb}, number = {11}, publisher = {De Gruyter}, address = {Berlin}, issn = {0947-0085}, doi = {10.3139/104.112012}, pages = {767 -- 770}, year = {2018}, abstract = {Das Forschungsprojekt Produktionseffizienz in der Kleinserie (ProeK) erarbeitet kosteng{\"u}nstige und effiziente L{\"o}sungsans{\"a}tze f{\"u}r Prozessketten im Zukunftsfeld der Elektromobilit{\"a}t. Das Teilprojekt Karosserie setzt diese Zielsetzung durch innovative und praxisorientierte Produkt- und Prozesskonzepte mit neuartigen bauteilintegrierten Vorrichtungsfunktionen (BiV) um. Im Teilprojekt Außenhaut sollen Toleranzen adaptiv durch Anpassungen der Prozessparameter sowie Bauteilmanipulation kompensiert werden.}, language = {de} } @article{BergSchleserDelidovichetal.2018, author = {Berg, Alexander-Karl and Schleser, Markus and Delidovich, Artem and Houben, Alexander}, title = {Ultraschallunterst{\"u}tzter Schmelzklebstoffauftrag}, series = {adh{\"a}sion KLEBEN \& DICHTEN}, volume = {Volume 62}, journal = {adh{\"a}sion KLEBEN \& DICHTEN}, number = {Issue 12}, publisher = {Springer}, doi = {10.1007/s35145-018-0089-z}, pages = {32 -- 37}, year = {2018}, language = {de} } @article{FranzenPindersPfaffetal.2018, author = {Franzen, Julius and Pinders, Erik and Pfaff, Raphael and Enning, Manfred}, title = {RailCrowd's virtual fleets: Make most of your asset data}, series = {Deine Bahn}, journal = {Deine Bahn}, number = {9}, publisher = {Bahn-Fachverlag}, address = {Berlin}, issn = {0948-7263}, pages = {11 -- 13}, year = {2018}, abstract = {For smaller railway operators or those with a diverse fleet, it can be difficult to collect sufficient data to improve maintenance programs. At the same time, new rules such as entity in charge of maintenance - ECM - regulations impose an additional workload by requiring a dedicated maintenance management system and specific reports. The RailCrowd platform sets out to facilitate compliance with ECM and similar regulations while at the same time pooling anonymised fleet data across operators to form virtual fleets, providing greater data insights.}, language = {en} } @article{SchmidtEnningPfaff2018, author = {Schmidt, Bernd and Enning, Manfred and Pfaff, Raphael}, title = {G{\"u}terwagen 4.0 - Der G{\"u}terwagen f{\"u}r das Internet der Dinge Teil 3: Einf{\"u}hrungsszenarien f{\"u}r aktive, kommunikative G{\"u}terwagen}, series = {ETR - Eisenbahntechnische Rundschau}, volume = {67}, journal = {ETR - Eisenbahntechnische Rundschau}, number = {5}, publisher = {DVV Media Group}, address = {Hamburg}, issn = {0013-2845}, pages = {60 -- 64}, year = {2018}, abstract = {Wenn durch innovative, automatisierte G{\"u}terwagen betriebswirtschaftliche Vorteile nutzbar gemacht werden sollen, muss die Migration auf das neue System in sinnvollen Teilschritten unter Ber{\"u}cksichtigung der organisationellen und betrieblichen Vereinbarkeit vorgenommen werden. Eine stufenweise Migration mit Nachr{\"u}stbarkeit und Kompatibilit{\"a}t kann die optimale Ausstattungsvariante f{\"u}r die unterschiedlichen Betriebsszenarien sowie eine Steigerung der Wirtschaftlichkeit des Gesamtsystems bieten.}, language = {de} } @article{Thomas2018, author = {Thomas, Axel}, title = {Technologiezentren in der Aachener Region - Retrospektiven und Perspektiven}, series = {VM Verwaltung und Management}, volume = {24}, journal = {VM Verwaltung und Management}, number = {3}, publisher = {Nomos}, address = {Baden-Baden}, issn = {0947-9856}, doi = {10.5771/0947-9856-2018-3-147}, pages = {147 -- 156}, year = {2018}, language = {de} } @article{Thomas2018, author = {Thomas, Axel}, title = {Zielerreichungen der Technologie- und Gr{\"u}nderzentren aus Sicht der kommunalen Finanzwirtschaft - dargestellt am Beispiel der Aachener Region}, series = {Der Gemeindehaushalt}, volume = {119}, journal = {Der Gemeindehaushalt}, number = {7}, publisher = {Kohlhammer}, address = {Stuttgart}, issn = {0340-3645}, pages = {149 -- 155}, year = {2018}, language = {de} } @article{KlockeRichertSube2018, author = {Klocke, Martina and Richert, Vera and Sube, Maike}, title = {Vier Jahre „Guter Studienstart im Ingenieurbereich": Entwicklung und Perspektiven des „Nullten Semesters" in Aachen}, series = {Zeitschrift f{\"u}r Beratung und Studium}, volume = {13}, journal = {Zeitschrift f{\"u}r Beratung und Studium}, number = {1}, publisher = {Universit{\"a}tsverlag Webler}, address = {Bielefeld}, issn = {1860-3068}, pages = {17 -- 22}, year = {2018}, abstract = {Bereits 2015 wurde in der Zeitschrift „Qualit{\"a}t in der Wissenschaft" (QiW) {\"u}ber das Kooperationsprojekt „Guter Studienstart im Ingenieurbereich", das Orientierungssemester von RWTH und FH Aachen, berichtet. In diesem Artikel legen wir den Schwerpunkt auf die Entwicklung des Projekts in den Jahren 2015 bis 2018 und geben eine R{\"u}ckschau sowie einen Ausblick auf die Entwicklungsperspektiven nach dem offiziellen Projektende.}, language = {de} } @article{BabilonWilbringTappertetal.2018, author = {Babilon, Katharina and Wilbring, Daniela and Tappert, Tim and Pfaff, Raphael and Enning, Manfred}, title = {Schienenfahrzeugtechnik hands on - FH Aachen IMechE Railway Challenge}, series = {Ingenieurspiegel}, journal = {Ingenieurspiegel}, number = {2}, publisher = {Public Verlag}, address = {Bingen}, issn = {1868-5919}, pages = {20 -- 22}, year = {2018}, language = {de} } @article{ZieburaBremenSchleifenbaumetal.2018, author = {Ziebura, Dawid and Bremen, Sebastian and Schleifenbaum, Johannes Henrich and Gebhardt, Andreas}, title = {Machbarkeitsstudie zur Verarbeitung von nicht rostendem Stahl 1.4404 unter Verwendung einer Diodenlaser-basierten LPBF-Maschine mit kartesischem Achssystem}, series = {RTejournal - Forum f{\"u}r Rapid Technologie}, volume = {15}, journal = {RTejournal - Forum f{\"u}r Rapid Technologie}, issn = {1614-0923}, year = {2018}, language = {de} } @article{KilicRaatschenKoerfgenetal.2017, author = {Kilic, S. A. and Raatschen, Hans-J{\"u}rgen and K{\"o}rfgen, B. and Apaydin, N. M. and Astaneh-Asl, A.}, title = {FE Model of the Fatih Sultan Mehmet Suspension Bridge Using Thin Shell Finite Elements}, series = {Arabian Journal for Science and Engineering}, volume = {42}, journal = {Arabian Journal for Science and Engineering}, number = {3}, publisher = {Springer Nature}, issn = {2191-4281}, doi = {10.1007/s13369-016-2316-y}, pages = {1103 -- 1116}, year = {2017}, abstract = {This paper presents the results of an eigenvalue analysis of the Fatih Sultan Mehmet Bridge. A high-resolution finite element model was created directly from the available design documents. All physical properties of the structural components were included in detail, so no calibration to the measured data was necessary. The deck and towers were modeled with shell elements. A nonlinear static analysis was performed before the eigenvalue calculation. The calculated natural frequencies and corresponding mode shapes showed good agreement with the available measured ambient vibration data. The calculation of the effective modal mass showed that nine modes had single contributions higher than 5 \% of the total mass. They were in a frequency range up to 1.2 Hz. The comparison of the results for the torsional modes especially demonstrated the advantage of using thin shell finite elements over the beam modeling approach.}, language = {en} } @article{EnningPfaff2017, author = {Enning, Manfred and Pfaff, Raphael}, title = {G{\"u}terwagen 4.0 - Der G{\"u}terwagen f{\"u}r das Internet der Dinge. Teil 1: Gesamtsystembetrachtung und grundlegendes Konzept}, series = {ETR - Eisenbahntechnische Rundschau}, volume = {66}, journal = {ETR - Eisenbahntechnische Rundschau}, number = {1/2}, publisher = {DVV Media Group}, address = {Hamburg}, issn = {0013-2845}, pages = {12 -- 16}, year = {2017}, language = {de} } @article{Enning2017, author = {Enning, Manfred}, title = {Vom "K{\"o}nig der Landstraße" zur "Ameise 4.0"}, series = {ETR - Eisenbahntechnische Rundschau}, volume = {66}, journal = {ETR - Eisenbahntechnische Rundschau}, number = {1/2}, publisher = {DVV Media Group}, address = {Hamburg}, issn = {0013-2845}, pages = {3}, year = {2017}, abstract = {Auf Eisenbahn- und Logistikkonferenzen werden gelegentlich Videos von Blattschneiderameisen gezeigt, die effizient und selbstorganisiert große Mengen Material durch den Dschungel transportieren. Daran sollen wir uns ein Beispiel nehmen.}, language = {de} } @article{PfaffEnning2017, author = {Pfaff, Raphael and Enning, Manfred}, title = {G{\"u}terwagen 4.0 - Der G{\"u}terwagen f{\"u}r das Internet der Dinge. Teil 2: Ausgew{\"a}hlte technische Aspekte und Prozesse}, series = {ETR - Eisenbahntechnische Rundschau}, volume = {66}, journal = {ETR - Eisenbahntechnische Rundschau}, number = {5}, publisher = {DVV Media Group}, address = {Hamburg}, issn = {0013-2845}, pages = {74 -- 77}, year = {2017}, language = {de} } @article{ReisgenSchaeferWilmsetal.2017, author = {Reisgen, Uwe and Sch{\"a}fer, Johannes and Wilms, Konrad and Schleser, Markus}, title = {Aufmischungsarmes, dickschichtiges MSG-Auftragschweißen mit entkoppelter Zweidrahttechnik}, series = {Schweißen und Schneiden}, volume = {69}, journal = {Schweißen und Schneiden}, number = {12}, publisher = {DVS Verlag}, address = {D{\"u}sseldorf}, issn = {0036-7184}, pages = {838 -- 843}, year = {2017}, abstract = {F{\"u}r Auftragschweißaufgaben existiert eine Vielzahl an verfahrenstechnischen Prozessvarianten, die je nach Charakteristik und Anwendungsfall ausgew{\"a}hlt werden. Ein Nachteil der vorwiegend verwendeten Metall- Schutzgasschweißprozesse (MSG) f{\"u}r das Auftragschweißen ist durch die direkte Kopplung von Drahtvorschub zu Energieeintrag gegeben. Die vorgestellte Zweidraht-Prozessvariante kann durch die Ausbildung eines {\"u}bertragenen und eines nicht-{\"u}bertragenen Lichtbogens die elektrische Leistung beider Lichtb{\"o}gen variieren und damit einen direkten Einfluss auf die Prozessgr{\"o}ßen Abschmelzleistung und Aufschmelzgrad nehmen. Im Speziellen besteht {\"u}ber die Entkopplung von Drahtvorschub zu Schweißstromst{\"a}rke die M{\"o}glichkeit eines niederenergetischen Betriebs trotz hoher Drahtvorschubgeschwindigkeit. Damit lassen sich Aufschmelzgrade unter 2\% umsetzen und Abschmelzleistungen bis zu 15 kg/h realisieren.}, language = {de} } @article{Pfaff2017, author = {Pfaff, Raphael}, title = {Einsatz von offenen Onlinekursen in der Eisenbahnlehre}, series = {Deine Bahn}, journal = {Deine Bahn}, number = {1}, publisher = {Bahn-Fachverlag}, address = {Berlin}, issn = {0948-7263}, pages = {12 -- 16}, year = {2017}, abstract = {Eigene positive Erfahrungen mit Onlinekursen sowie die geringen Studierendenzahlen in der Pr{\"a}senzlehre gaben den Anstoß zu einem Experiment mit einem offenen Onlinekurs auf der Plattform Udemy. Die Erfahrungen sowohl bei der Erstellung und als auch im Lehrbetrieb waren positiv und f{\"u}hrten zu einer neuen Besch{\"a}ftigung mit Inhalten und Lernenden, getrieben durch die Anforderungen der Lernplattform.}, language = {de} } @article{Wollert2017, author = {Wollert, J{\"o}rg}, title = {Echtzeit-Ethernet - Basis f{\"u}r Industrie 4.0}, series = {Design \& Elektronik}, journal = {Design \& Elektronik}, number = {12}, publisher = {WEKA-Fachmedien}, address = {Haar, M{\"u}nchen}, issn = {0933-8667}, pages = {38 -- 41}, year = {2017}, language = {de} } @article{Pfaff2017, author = {Pfaff, Raphael}, title = {Apps f{\"u}r den G{\"u}terwagen? Wie der G{\"u}terwagen 4.0 die effiziente Integration der G{\"u}terbahn in ERTMS erm{\"o}glicht}, series = {Ingenieurspiegel}, journal = {Ingenieurspiegel}, number = {2}, pages = {1 -- 2}, year = {2017}, language = {de} } @article{PfaffEnning2017, author = {Pfaff, Raphael and Enning, Manfred}, title = {Die nachhaltige Alternative zum autonomen Lastwagen}, series = {Deine Bahn}, journal = {Deine Bahn}, number = {10}, pages = {22 -- 26}, year = {2017}, language = {de} } @article{Reichert2017, author = {Reichert, Walter}, title = {Berufseinstieg f{\"u}r Wirtschaftsingenieure - Bachelor oder Master?}, series = {Berufsstart}, journal = {Berufsstart}, year = {2017}, language = {de} } @article{Wollert2016, author = {Wollert, J{\"o}rg}, title = {Rapid Application Development}, series = {Design \& Elektronik}, journal = {Design \& Elektronik}, number = {4}, publisher = {WEKA-Fachmedien}, address = {M{\"u}nchen}, issn = {0933-8667}, pages = {8 -- 11}, year = {2016}, abstract = {Das IoT ist ohne eingebettete Systeme undenkbar. Erst kleine und kleinste Mikrocontroller mit intelligenten Kommunikationsschnittstellen und Anbindung ans Internet erm{\"o}glichen sinnvolles und fl{\"a}chendeckendes Einsammeln von Daten. Doch wie kompliziert ist der Einstieg in die Embedded-Welt? Dieser Artikel gibt Einblick, wie die »Arduino-Plattform« die Einstiegsh{\"u}rden f{\"u}r eingebettete Systeme dramatisch reduzieren kann.}, language = {de} } @article{Wollert2016, author = {Wollert, J{\"o}rg}, title = {Industrial Internet of Things : Seifenblase oder Revolution}, series = {Elektronik}, journal = {Elektronik}, number = {7}, publisher = {WEKA-Fachmedien}, address = {M{\"u}nchen}, issn = {0013-5658}, pages = {39 -- 45}, year = {2016}, language = {de} } @article{KosterScheidweilerTieves2016, author = {Koster, Arie and Scheidweiler, Robert and Tieves, Martin}, title = {A flow based pruning scheme for enumerative equitable coloring algorithms}, series = {A flow based pruning scheme for enumerative equitable coloring algorithms}, journal = {A flow based pruning scheme for enumerative equitable coloring algorithms}, doi = {10.48550/arXiv.1607.08754}, pages = {1 -- 30}, year = {2016}, abstract = {An equitable graph coloring is a proper vertex coloring of a graph G where the sizes of the color classes differ by at most one. The equitable chromatic number is the smallest number k such that G admits such equitable k-coloring. We focus on enumerative algorithms for the computation of the equitable coloring number and propose a general scheme to derive pruning rules for them: We show how the extendability of a partial coloring into an equitable coloring can be modeled via network flows. Thus, we obtain pruning rules which can be checked via flow algorithms. Computational experiments show that the search tree of enumerative algorithms can be significantly reduced in size by these rules and, in most instances, such naive approach even yields a faster algorithm. Moreover, the stability, i.e., the number of solved instances within a given time limit, is greatly improved. Since the execution of flow algorithms at each node of a search tree is time consuming, we derive arithmetic pruning rules (generalized Hall-conditions) from the network model. Adding these rules to an enumerative algorithm yields an even larger runtime improvement.}, language = {en} } @article{BeckenbachScheidweiler2016, author = {Beckenbach, Isabel and Scheidweiler, Robert}, title = {Perfect ƒ-Matchings and ƒ-Factors in Hypergraphs - A Combinatorial Approach}, series = {Discrete Mathematics}, volume = {240}, journal = {Discrete Mathematics}, number = {10}, publisher = {Elsevier}, address = {Amsterdam}, issn = {2192-7782}, doi = {10.1016/j.disc.2017.05.005}, pages = {2499 -- 2506}, year = {2016}, abstract = {We prove characterizations of the existence of perfect ƒ-matchings in uniform mengerian and perfect hypergraphs. Moreover, we investigate the ƒ-factor problem in balanced hypergraphs. For uniform balanced hypergraphs we prove two existence theorems with purely combinatorial arguments, whereas for non-uniform balanced hypergraphs we show that the ƒ-factor problem is NP-hard.}, language = {en} } @article{ScheidweilerTriesch2016, author = {Scheidweiler, Robert and Triesch, Eberhard}, title = {A note on the duality between matchings and vertex covers in balanced hypergraphs}, series = {Journal of Combinatorial Optimization}, volume = {32}, journal = {Journal of Combinatorial Optimization}, number = {2}, publisher = {Springer}, address = {Berlin}, issn = {1573-2886}, doi = {10.1007/s10878-015-9887-5}, pages = {639 -- 644}, year = {2016}, abstract = {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.}, language = {en} } @article{RieperGebhardtStucker2016, author = {Rieper, Harald and Gebhardt, Andreas and Stucker, Brent}, title = {Selective Laser Melting of the Eutectic Silver-Copper Alloy Ag 28 wt \% Cu}, series = {RTejournal - Forum f{\"u}r Rapid Technologie}, volume = {13}, journal = {RTejournal - Forum f{\"u}r Rapid Technologie}, issn = {1614-0923}, url = {http://nbn-resolving.de/nbn:de:0009-2-44141}, year = {2016}, abstract = {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.}, language = {en} } @article{WollertBooke2016, author = {Wollert, J{\"o}rg and Booke, Andreas}, title = {IoT von der Stange}, series = {elektronik}, journal = {elektronik}, number = {21 (2016)}, publisher = {WEKA-Fachmedien}, address = {M{\"u}nchen}, pages = {30 -- 37}, year = {2016}, abstract = {Heute sollte am besten jedes Ger{\"a}t in die große Rechnerwolke eingebettet werden. Doch so einfach ist das nicht, denn Cloud ist viel mehr als nur das Internet der Dinge. Als Anwender muss man sich also fragen, welche Dienste man m{\"o}chte und welchem Anbieter man sein Vertrauen schenkt.}, language = {de} } @article{Wollert2016, author = {Wollert, J{\"o}rg}, title = {OS-Funktionalit{\"a}t ohne OS f{\"u}r das IoT}, series = {Design \& Elektronik}, journal = {Design \& Elektronik}, number = {11}, publisher = {WEKA-Fachmedien}, address = {M{\"u}nchen}, issn = {0933-8667}, pages = {85 -- 90}, year = {2016}, abstract = {Low-end-Embedded-Plattformen stellen eine hohe Anforderung an die Entscheidungsf{\"a}higkeit des Entwicklers: Zum n{\"a}chstgr{\"o}ßeren Prozessor greifen und ein Betriebssystem benutzen oder doch besser auf das Betriebssystem verzichten? Die Frage l{\"a}sst sich einfach beantworten: Einen Nanokernel verwenden und das Embedded-System mit einem minimalen Footprint realisieren. Adam Dunkels Protothreads sind eine ausgesprochen effiziente Art, Mikrocontroller gut strukturiert zu programmieren und gleichzeitig auf Overhead zu verzichten. So k{\"o}nnen auch mit kleinen 8-bit-Prozessoren anspruchsvolle Aufgaben in einem Thread-Modell bearbeitet werden. Man muss also nicht immer das Rad neu erfinden oder gleich auf Linux-basierte Systeme zur{\"u}ckgreifen.}, language = {de} } @article{Thomas2016, author = {Thomas, Axel}, title = {Genussrechte als Instrument der Unternehmensfinanzierung von kommunalen Wohnungs- baugesellschaften}, series = {VM Verwaltung und Management}, volume = {22}, journal = {VM Verwaltung und Management}, number = {6}, publisher = {Nomos}, address = {Baden-Baden}, issn = {0947-9856}, doi = {10.5771/0947-9856-2016-6-322}, pages = {322 -- 327}, year = {2016}, abstract = {Die kommunalen Wohnungsbaugesellschaften und ihr Gesch{\"a}ftszweck bzw. Versorgungsauftrag erfahren aus gesamtgesellschaftlichen Gr{\"u}nden aktuell einen erheblichen Bedeutungszuwachs. Der kommunale Wohnungsbau soll und muss intensiviert werden, da z.B. zunehmend Wohnungsbindungen auslaufen. Bezahlbare Neubauten fehlen speziell Familien, Senioren, Studenten und Fl{\"u}chtlingen. Um das Investitionsvolumen zu bew{\"a}ltigen, bedarf es nicht nur der F{\"o}rderkredite, sondern auch der Zuf{\"u}hrung „frischen Kapitals". Der Beitrag stellt dar, dass Genussrechte ein interessantes und oft unbekanntes Finanzierungsinstrument f{\"u}r kommunale Wohnungsbaugesellschaften mit passgenauen Ausgestaltungsm{\"o}glichkeiten sind. Mit Hilfe von Genussrechten k{\"o}nnen die notwendigen Neubau-Investitionen solide mit Quasi-Eigenkapital unterlegt werden und den sozialen Wohnungsbau wiederbeleben. Genussrechte als Hybridkapital lassen sich mangels gesetzlicher Eingrenzung exakt und individuell ebenso an die Bed{\"u}rfnisse der kommunalen Wohnungsbaugesellschaft anpassen wie an die der Gesellschafter und des jeweiligen Neubauvorhabens.}, language = {de} } @article{PfaffSchmidt2016, author = {Pfaff, Raphael and Schmidt, Bernd}, title = {Daten in der Cloud - und dann?}, series = {Deine Bahn}, journal = {Deine Bahn}, number = {6}, publisher = {Bahn-Fachverlag}, address = {Berlin}, issn = {0948-7263}, pages = {50 -- 55}, year = {2016}, abstract = {Schienenverkehrssysteme stehen in zunehmendem Wettbewerb, sowohl untereinander als auch mit anderen Verkehrstr{\"a}gern. Als wichtiger Aspekt zur Steigerung der Kosteneffizienz wird die Digitalisierung des Betriebs und der Fahrzeuge betrachtet. {\"U}ber eine Prognose der Ausfallwahrscheinlichkeit bzw. Restlebensdauer von Subsystemen k{\"o}nnen mittels Digitalisierung die Instandhaltungskosten gesenkt werden. Die geringen Fehlerraten im System Bahn machen die Nutzung besonderer Simulationstechniken notwendig. In diesem Beitrag wird gezeigt, wie sich die Subsystemverf{\"u}gbarkeit aus den beobachteten Fehlerraten der Teilfunktionen vorhersagen l{\"a}sst.}, language = {de} } @article{FateriGebhardt2015, author = {Fateri, Miranda and Gebhardt, Andreas}, title = {Selective Laser Melting of Soda-Lime Glass Powder}, series = {International Journal of Applied Ceramic Technology}, volume = {12}, journal = {International Journal of Applied Ceramic Technology}, number = {1}, publisher = {Wiley-Blackwell}, address = {Oxford}, issn = {1744-7402}, doi = {10.1111/ijac.12338}, pages = {53 -- 61}, year = {2015}, language = {en} } @article{FateriGebhardt2015, author = {Fateri, Miranda and Gebhardt, Andreas}, title = {Process Parameters Development of Selective Laser Melting of Lunar Regolith for On-Site Manufacturing Applications}, series = {International Journal of Applied Ceramic Technology}, volume = {12}, journal = {International Journal of Applied Ceramic Technology}, number = {1}, publisher = {Wiley-Blackwell}, address = {Oxford}, isbn = {1744-7402}, doi = {10.1111/ijac.12326}, pages = {46 -- 52}, year = {2015}, language = {en} } @article{FateriGebhardt2015, author = {Fateri, Miranda and Gebhardt, Andreas}, title = {Additive manufactured mechanical disentanglement lock}, series = {RTejournal - Forum f{\"u}r Rapid Technologie}, volume = {12}, journal = {RTejournal - Forum f{\"u}r Rapid Technologie}, publisher = {Fachhochschule Aachen}, address = {Aachen}, issn = {1614-0923}, url = {http://nbn-resolving.de/urn:nbn:de:0009-2-42147}, year = {2015}, language = {en} } @article{Wollert2015, author = {Wollert, J{\"o}rg}, title = {IO-Link - f{\"u}r smarte Sensoren}, series = {elektroniknet.de}, journal = {elektroniknet.de}, year = {2015}, language = {de} } @article{Wollert2015, author = {Wollert, J{\"o}rg}, title = {Echtzeit-Ethernet : Protokoll-Reigen}, series = {elektroniknet.de}, journal = {elektroniknet.de}, year = {2015}, language = {de} } @article{KesslerBalcGebhardtetal.2015, author = {Kessler, Julia and Balc, Nicolae and Gebhardt, Andreas and Abbas, Karim}, title = {Basic Research on Lattice Structures Focused on the Tensile Strength}, series = {Applied Mechanics and Materials}, volume = {Vol. 808}, journal = {Applied Mechanics and Materials}, publisher = {Trans Tech Publications}, address = {B{\"a}ch}, issn = {1662-7482}, doi = {10.4028/www.scientific.net/AMM.808.193}, pages = {193 -- 198}, year = {2015}, language = {en} } @article{Pfaff2015, author = {Pfaff, Raphael}, title = {Praxisnahe Ausbildung im Fach Schienenfahrzeugtechnik}, series = {Deine Bahn}, journal = {Deine Bahn}, number = {8}, publisher = {Eisenbahn-Fachverlag}, address = {Mainz}, issn = {0172-4479}, pages = {52 -- 55}, year = {2015}, language = {de} } @article{PfaffSchmidtPinders2015, author = {Pfaff, Raphael and Schmidt, Bernd and Pinders, Udo}, title = {Energieeffizienz steigern durch Rekuperationseinrichtungen}, series = {Deine Bahn}, journal = {Deine Bahn}, number = {5}, publisher = {Eisenbahn-Fachverlag}, address = {Mainz}, issn = {0172-4479}, pages = {50 -- 53}, year = {2015}, language = {de} } @article{Gebhardt2015, author = {Gebhardt, Andreas}, title = {3D-Druck ist {\"u}berall. Modische Accessoires, Kleidung, Medikamente, Nahrungsmittel, Autos, H{\"a}user, Waffen, B{\"u}sten, Musikinstrumente - alles geht}, series = {Kunststoffe}, volume = {105}, journal = {Kunststoffe}, number = {10}, publisher = {Hanser}, address = {M{\"u}nchen}, issn = {0023-5563}, pages = {62 -- 70}, year = {2015}, language = {de} } @article{GebhardtFateri2014, author = {Gebhardt, Andreas and Fateri, Miranda}, title = {3D-Drucken und die Anwendungen}, series = {RTejournal - Forum f{\"u}r Rapid Technologie}, volume = {11 (2014)}, journal = {RTejournal - Forum f{\"u}r Rapid Technologie}, number = {1}, issn = {1614-0923}, pages = {1 -- 9}, year = {2014}, language = {de} } @article{GebhardtHoetterZiebura2014, author = {Gebhardt, Andreas and H{\"o}tter, Jan-Steffen and Ziebura, Dawid}, title = {Impact of SLM build parameters on the surface quality}, series = {RTejournal - Forum f{\"u}r Rapid Technologien}, volume = {11 (2014)}, journal = {RTejournal - Forum f{\"u}r Rapid Technologien}, number = {1}, issn = {1614-0923}, pages = {1 -- 14}, year = {2014}, language = {de} } @article{FiedlerHennMelcher2014, author = {Fiedler, Gerda and Henn, Gudrun and Melcher, Karin}, title = {ANPAK - ein semesterbegleitender Anpassungskurs}, series = {Zeitschrift f{\"u}r Hochschulentwicklung}, volume = {9}, journal = {Zeitschrift f{\"u}r Hochschulentwicklung}, number = {4}, publisher = {{\"O}GHD}, address = {Wien}, issn = {2219-6994}, pages = {85 -- 100}, year = {2014}, abstract = {In Folge mehrj{\"a}hriger statistischer Untersuchungen an der FH Aachen ist unter anderem ein Eingangstest entstanden, der als Diagnosetool f{\"u}r einen erfolgreichen Studieneinstieg verwendet wird. Es hat sich herausgestellt, dass ein Testergebnis von weniger als 25 (von maximal 56 erreichbaren) Punkten die Chance auf einen erfolgreichen Studieneinstieg deutlich verringert. Ungef{\"a}hr die H{\"a}lfte aller Erstsemester hat weniger als 25 Punkte im Eingangstest. Weniger als 20 \% dieser Gruppe bestehen innerhalb eines Jahres die Klausur Mathematik 1. Die investierte Zeit von zwei Semestern ist mit Blick auf den Wissenszuwachs und damit letztendlich den Studienerfolg nicht effizient genutzt. Deshalb haben wir im WS 2013/14 einen semesterbegleitenden Anpassungskurs f{\"u}r diese Gruppe installiert. Ziel eines solchen Kurses ist es, die Student/innen innerhalb eines Jahres in die Lage zu versetzen, nach zwei Semestern problemlos den Vorlesungen in Mathematik zu folgen. Dieser Artikel beschreibt das Konzept dieses Anpassungskurses und zeigt erste Ergebnisse und Probleme des Pilotdurchgangs auf.}, language = {de} } @article{FateriGebhardtThuemmleretal.2014, author = {Fateri, Miranda and Gebhardt, Andreas and Th{\"u}mmler, Stefan and Thurn, Laura}, title = {Experimental investigation on selective laser melting of glass}, series = {Physics procedia : 8th International Conference on Laser Assisted Net Shape Engineering LANE 2014}, volume = {56 (2014)}, journal = {Physics procedia : 8th International Conference on Laser Assisted Net Shape Engineering LANE 2014}, publisher = {Elsevier}, address = {Amsterdam}, issn = {1875-3892 (E-Journal); 1875-3884 (Print)}, doi = {10.1016/j.phpro.2014.08.118}, pages = {357 -- 364}, year = {2014}, language = {en} } @article{Thomas2014, author = {Thomas, Axel}, title = {Generation Y}, series = {P.T. : Magazin f{\"u}r Wirtschaft und Gesellschaft}, volume = {10}, journal = {P.T. : Magazin f{\"u}r Wirtschaft und Gesellschaft}, number = {3}, publisher = {OPS Netzwerk}, address = {Leipzig}, issn = {1860-501X}, pages = {6 -- 9}, year = {2014}, language = {de} } @article{ThomasWassenberg2014, author = {Thomas, Axel and Wassenberg, Gerd}, title = {Erfolgreich sein im Kampf um die besten Talente : Employer Branding}, series = {Wirtschaftliche Nachrichten der Industrie- und Handelskammer Aachen}, journal = {Wirtschaftliche Nachrichten der Industrie- und Handelskammer Aachen}, publisher = {IHK Aachen}, address = {Aachen}, year = {2014}, language = {de} } @article{Wollert2014, author = {Wollert, J{\"o}rg}, title = {Funkstandards f{\"u}r Sensornetzwerke}, series = {Elektronik : Fachmedium f{\"u}r industrielle Anwender und Entwickler}, volume = {Bd. 63}, journal = {Elektronik : Fachmedium f{\"u}r industrielle Anwender und Entwickler}, number = {H. 12}, publisher = {WEKA-Fachmedien}, address = {Haar}, issn = {0013-5658}, pages = {36 -- 41}, year = {2014}, language = {de} } @article{Wollert2014, author = {Wollert, J{\"o}rg}, title = {Echtzeit-Ethernet : Protokoll-Reigen}, series = {Elektronik : Fachmedium f{\"u}r industrielle Anwender und Entwickler}, volume = {Bd. 63}, journal = {Elektronik : Fachmedium f{\"u}r industrielle Anwender und Entwickler}, number = {H. 26}, publisher = {WEKA-Fachmedien}, address = {Haar}, issn = {0013-5658}, pages = {24 -- 31}, year = {2014}, language = {de} } @article{Wollert2014, author = {Wollert, J{\"o}rg}, title = {Der Embedded Wireless-Report}, series = {Elektronik : Fachmedium f{\"u}r industrielle Anwender und Entwickler ; Sonderh. Wireless : Fachmedium f{\"u}r Entwicklungen funkbasierter Systeme}, journal = {Elektronik : Fachmedium f{\"u}r industrielle Anwender und Entwickler ; Sonderh. Wireless : Fachmedium f{\"u}r Entwicklungen funkbasierter Systeme}, publisher = {WEKA-Fachmedien}, address = {Haar}, issn = {0013-5658}, pages = {18 -- 25}, year = {2014}, language = {de} } @article{Wollert2014, author = {Wollert, J{\"o}rg}, title = {Echtzeit-Ethernet mit Standardtechnik}, series = {Elektronik : Fachmedium f{\"u}r industrielle Anwender und Entwickler ; Sonderh. Embedded : Fachmagazin f{\"u}r die Entwicklung von Embedded-Systemen}, volume = {Bd. 63}, journal = {Elektronik : Fachmedium f{\"u}r industrielle Anwender und Entwickler ; Sonderh. Embedded : Fachmagazin f{\"u}r die Entwicklung von Embedded-Systemen}, number = {H. 12}, publisher = {WEKA-Fachmedien}, address = {Haar}, issn = {0013-5658}, pages = {28 -- 32}, year = {2014}, language = {de} } @article{Wollert2014, author = {Wollert, J{\"o}rg}, title = {Feldbustechnologie}, series = {Factory : der Durchblick in der Technik}, journal = {Factory : der Durchblick in der Technik}, publisher = {WEKA-Industriemedien}, address = {Wien}, pages = {Publ. online}, year = {2014}, language = {de} } @article{HuberStreblowMuelleretal.2014, author = {Huber, M. and Streblow, R. and M{\"u}ller, D. and Lange, S. and Joneleit, R. and Sefker, T. and Rau, Sebastian and Wollert, J{\"o}rg}, title = {Funksignal{\"u}bertragung in Luftleitungen}, series = {HLH : L{\"u}ftung, Klima, Heizung, Sanit{\"a}r, Geb{\"a}udetechnik}, volume = {Bd. 65}, journal = {HLH : L{\"u}ftung, Klima, Heizung, Sanit{\"a}r, Geb{\"a}udetechnik}, number = {H. 7/8}, issn = {1436-5103}, pages = {36 -- 40}, year = {2014}, language = {de} } @article{HaagZontarSchleupenetal.2014, author = {Haag, S. and Zontar, D. and Schleupen, Josef and M{\"u}ller, T. and Brecher, C.}, title = {Chain of refined perception in self-optimizing assembly of micro-optical systems}, series = {Journal of sensors and sensor systems}, volume = {3}, journal = {Journal of sensors and sensor systems}, number = {1}, publisher = {Copernicus Publ.}, address = {G{\"o}ttingen}, issn = {2194-878X}, doi = {10.5194/jsss-3-87-2014}, pages = {87 -- 95}, year = {2014}, abstract = {Today, the assembly of laser systems requires a large share of manual operations due to its complexity regarding the optimal alignment of optics. Although the feasibility of automated alignment of laser optics has been shown in research labs, the development effort for the automation of assembly does not meet economic requirements - especially for low-volume laser production. This paper presents a model-based and sensor-integrated assembly execution approach for flexible assembly cells consisting of a macro-positioner covering a large workspace and a compact micromanipulator with camera attached to the positioner. In order to make full use of available models from computer-aided design (CAD) and optical simulation, sensor systems at different levels of accuracy are used for matching perceived information with model data. This approach is named "chain of refined perception", and it allows for automated planning of complex assembly tasks along all major phases of assembly such as collision-free path planning, part feeding, and active and passive alignment. The focus of the paper is put on the in-process image-based metrology and information extraction used for identifying and calibrating local coordinate systems as well as the exploitation of that information for a part feeding process for micro-optics. Results will be presented regarding the processes of automated calibration of the robot camera as well as the local coordinate systems of part feeding area and robot base.}, language = {en} } @article{GebhardtFateri2013, author = {Gebhardt, Andreas and Fateri, Miranda}, title = {3D printing and its applications}, series = {RTejournal - Forum f{\"u}r Rapid Technologie}, volume = {10}, journal = {RTejournal - Forum f{\"u}r Rapid Technologie}, number = {1}, publisher = {Fachhochschule Aachen}, address = {Aachen}, issn = {1614-0923}, url = {http://nbn-resolving.de/urn:nbn:de:0009-2-35626}, year = {2013}, abstract = {Eine zunehmende Anzahl von Artikeln in Publikumszeitschriften und Journalen r{\"u}ckt die direkte Herstellung von Bauteilen und Figuren immer mehr in das Bewusstsein einer breiten {\"O}ffentlichkeit. Leider ergibt sich nur selten ein einigermaßen vollst{\"a}ndiges Bild davon, wie und in welchen Lebensbereichen diese Techniken unseren Alltag ver{\"a}ndern werden. Das liegt auch daran, dass die meisten Artikel sehr technisch gepr{\"a}gt sind und sich nur punktuell auf Beispiele st{\"u}tzen. Dieser Beitrag geht von den Bed{\"u}rfnissen der Menschen aus, wie sie z.B. in der Maslow'schen Bed{\"u}rfnispyramide strukturiert dargestellt sind und unterstreicht dadurch, dass 3D Printing (oder Additive Manufacturing resp. Rapid Prototyping) bereits alle Lebensbereiche erfasst hat und im Begriff ist, viele davon zu revolutionieren.}, language = {en} } @article{ReisgenSchleserSchiebahn2013, author = {Reisgen, Uwe and Schleser, Markus and Schiebahn, Alexander}, title = {Untersuchung zum Einfluss von Maschineneigenschaften von Schweißzangen zum Widerstandspunktschweißen auf das Schweißergebnis}, series = {Schweissen und Schneiden : Fachzeitschrift f{\"u}r Schweißen und verwandte Verfahren}, volume = {Bd. 65}, journal = {Schweissen und Schneiden : Fachzeitschrift f{\"u}r Schweißen und verwandte Verfahren}, number = {H. 6}, publisher = {DVS Verl.}, address = {D{\"u}sseldorf}, issn = {0036-7184}, pages = {309 -- 313}, year = {2013}, language = {de} } @article{RamazaniLiMukherjeeetal.2013, author = {Ramazani, Ali and Li, Yang and Mukherjee, Krishnendu and Prahl, Ulrich and Bleck, Wolfgang and Abdurakhmanov, Aydemir and Schleser, Markus and Reisgen, Uwe}, title = {Microstructure evolution simulation in hot rolled DP600 steel during gas metal arc welding}, series = {Computational materials science}, volume = {Vol. 68}, journal = {Computational materials science}, publisher = {Elsevier}, address = {Amsterdam}, issn = {1879-0801 (E-Book); 0927-0256 (Print)}, pages = {107 -- 116}, year = {2013}, language = {en} } @article{FateriHoetterGebhardt2012, author = {Fateri, Miranda and H{\"o}tter, Jan-Steffen and Gebhardt, Andreas}, title = {Experimental and Theoretical Investigation of Buckling Deformation of Fabricated Objects by Selective Laser Melting}, series = {Physics Procedia}, volume = {39}, journal = {Physics Procedia}, publisher = {Elsevier}, address = {Amsterdam}, issn = {1875-3892}, doi = {10.1016/j.phpro.2012.10.062}, pages = {464 -- 470}, year = {2012}, abstract = {Although Selective Laser Melting (SLM) process is an innovative manufacturing method, there are challenges such as inferior mechanical properties of fabricated objects. Regarding this, buckling deformation which is caused by thermal stress is one of the undesired mechanical properties which must be alleviated. As buckling deformation is more observable in hard to process materials, silver is selected to be studied theoretically and experimentally for this paper. Different scanning strategies are utilized and a Finite Element Method (FEM) is applied to calculate the temperature gradient in order to determine its effect on the buckling deformation of the objects from experiments.}, language = {en} } @article{HoetterFateriGebhardt2012, author = {H{\"o}tter, Jan-Steffen and Fateri, Miranda and Gebhardt, Andreas}, title = {Prozessoptimierung des SLM-Prozesses mit hoch-reflektiven und thermisch sehr gut leitenden Materialien durch systematische Parameterfindung und begleitende Simulationen am Beispiel von Silber}, series = {RTejournal - Forum f{\"u}r Rapid Technologie}, volume = {9}, journal = {RTejournal - Forum f{\"u}r Rapid Technologie}, number = {1}, publisher = {Fachhoschule Aachen}, address = {Aachen}, issn = {1614-0923}, url = {http://nbn-resolving.de/urn:nbn:de:0009-2-33639}, pages = {1 -- 14}, year = {2012}, abstract = {Additive Manufacturing durch Aufschmelzen von Metallpulvern hat sich auf breiter Front als Herstellverfahren, auch f{\"u}r Endprodukte, etabliert. Besonders f{\"u}r die Variante des Selective Laser Melting (SLM) sind Anwendungen in der Zahntechnik bereits weit verbreitet und der Einsatz in sensitiven Branchen wie der Luftfahrt ist in greifbare N{\"a}he ger{\"u}ckt. Deshalb werden auch vermehrt Anstrengungen unternommen, um bisher nicht verarbeitete Materialien zu qualifizieren. Dies sind vorzugsweise Nicht-Eisen- und Edelmetalle, die sowohl eine sehr hohe Reflektivit{\"a}t als auch eine sehr gute W{\"a}rmeleitf{\"a}higkeit aufweisen - beides Eigenschaften, die die Beherrschung des Laser-Schmelzprozesses erschweren und nur kleine Prozessfenster zulassen. Die Arbeitsgruppe SLM des Lehr- und Forschungsgebietes Hochleistungsverfahren der Fertigungstechnik hat sich unter der Randbedingung einer kleinen und mit geringer Laserleistung ausgestatteten SLM Maschine der Aufgabe gewidmet und am Beispiel von Silber die Parameterfelder f{\"u}r Einzelspuren und wenig komplexe Geometrien systematisch untersucht. Die Arbeiten wurden von FEM Simulationen begleitet und durch metallographische Untersuchungen verifiziert. Die Ergebnisse bilden die Grundlage zur schnellen Parameterfindung bei komplexen Geometrien und bei Ver{\"a}nderungen der Zusammensetzung, wie sie bei zuk{\"u}nftigen Legierungen zu erwarten sind. Die Ergebnisse werden exemplarisch auf unterschiedliche Geometrien angewandt und entsprechende Bauteile gezeigt.}, language = {de} } @article{ReisgenSchleserMokrovetal.2012, author = {Reisgen, Uwe and Schleser, Markus and Mokrov, Oleg and Ahmed, Essam}, title = {Statistical modeling of laser welding of DP/TRIP steel sheets}, series = {Optics and laser technology}, volume = {44}, journal = {Optics and laser technology}, number = {1}, publisher = {Elsevier}, address = {Amsterdam}, issn = {1879-2545 (E-Journal); 0030-3992 (Print); 0308-4280 (Print)}, doi = {10.1016/j.optlastec.2011.05.025}, pages = {92 -- 101}, year = {2012}, abstract = {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.}, language = {en} } @article{ReisgenSchleserMokrovetal.2012, author = {Reisgen, Uwe and Schleser, Markus and Mokrov, Oleg and Ahmed, Essam}, title = {Optimization of laser welding of DP/TRIP steel sheets using statistical approach}, series = {Optics and laser technology}, volume = {44}, journal = {Optics and laser technology}, number = {1}, publisher = {Elsevier}, address = {Amsterdam}, issn = {1879-2545 (E-Journal); 0030-3992 (Print); 0308-4280 (Print)}, doi = {10.1016/j.optlastec.2011.06.028}, pages = {255 -- 262}, year = {2012}, abstract = {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.}, language = {en} } @article{ReisgenOlschokJakobsetal.2012, author = {Reisgen, Uwe and Olschok, Simon and Jakobs, Stefan and Schleser, Markus and Mokrov, Oleg and Rossiter, Eduardo}, title = {Laser beam submerged arc hybrid welding}, series = {Physics procedia}, volume = {39}, journal = {Physics procedia}, publisher = {Elsevier}, address = {Amsterdam}, issn = {1875-3892}, doi = {10.1016/j.phpro.2012.10.016}, pages = {75 -- 83}, year = {2012}, abstract = {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.}, language = {en} } @article{ReisgenSchleserAbdurakhmanovetal.2012, author = {Reisgen, Uwe and Schleser, Markus and Abdurakhmanov, Aydemir and Gumenyuk, Andrey}, title = {Measuring of plasma properties induced by non-vacuum electron beam welding}, series = {Physics of plasma}, volume = {19}, journal = {Physics of plasma}, number = {1}, publisher = {AIP Publishing}, address = {Melville, NY}, issn = {1089-7674 (E-Journal); 1070-664X (Print)}, doi = {10.1063/1.3675874}, pages = {1 -- 7}, year = {2012}, abstract = {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.}, language = {en} } @article{ReisgenSchleserMokrovetal.2012, author = {Reisgen, Uwe and Schleser, Markus and Mokrov, Oleg and Zabirov, Alexander and F{\"u}ssel, Uwe and Schnick, Michael and Hertel, Martin and Jaeckel, Sebastian}, title = {Modellierung und Visualisierung der MSG-Lichtbogenprozesse}, series = {Schweissen und Schneiden : Fachzeitschrift f{\"u}r Schweißen und verwandte Verfahren}, volume = {64}, journal = {Schweissen und Schneiden : Fachzeitschrift f{\"u}r Schweißen und verwandte Verfahren}, number = {4}, publisher = {DVS Verlag}, address = {D{\"u}sseldorf}, issn = {0036-7184}, pages = {166 -- 174}, year = {2012}, language = {de} } @article{ScheikSchleserReisgen2012, author = {Scheik, Sven and Schleser, Markus and Reisgen, Uwe}, title = {Thermisches Direktf{\"u}gen von Metall und Kusntstoff: eine Alternative zur Klebtechnik}, series = {Adh{\"a}sion : Kleben \& Dichten}, volume = {56}, journal = {Adh{\"a}sion : Kleben \& Dichten}, number = {11}, publisher = {Springer Vieweg}, address = {Wiesbaden}, issn = {0001-8198 (E-Journal); 0001-8198 (Print)}, doi = {10.1007/s35145-012-0005-x}, pages = {36 -- 40}, year = {2012}, abstract = {Im Rahmen des Exzellenzclusters „Integrative Produktionstechnik f{\"u}r Hochlohnl{\"a}nder" der RWTHAachen University werden derzeit alternative Verfahren zur Herstellung von Metall/Kunststoff- Verbindungen untersucht. Eines davon ist das thermische Direktf{\"u}gen, das eine stoffschl{\"u}ssige Verbindung zwischen Kunststoff und Metall erm{\"o}glicht und ohne die Verwendung von Klebstoffen, Haftvermittlern oder mechanischen Verbindungshilfen auskommt.}, language = {de} } @article{ReisgenSchleserMokrovetal.2012, author = {Reisgen, Uwe and Schleser, Markus and Mokrov, Oleg and Zabirov, Alexander and F{\"u}ssel, Uwe and Schnick, Michael and Hertel, Martin and Jaeckel, Sebastian}, title = {Modelling and visualisation of the GMA process}, series = {Welding and Cutting}, volume = {11}, journal = {Welding and Cutting}, number = {4}, publisher = {DVS Verlag}, address = {D{\"u}sseldorf}, issn = {1612-3433}, pages = {242 -- 249}, year = {2012}, language = {en} } @article{HoetterFateriGebhardt2012, author = {H{\"o}tter, Jan-Steffen and Fateri, Miranda and Gebhardt, Andreas}, title = {Selective laser melting of metals: desktop machines open up new chances even for small companies}, series = {Advanced materials research}, volume = {622-623}, journal = {Advanced materials research}, publisher = {Trans Tech Publ.}, address = {Baech}, issn = {1662-8985 (E-Journal); 1022-6680 (Print)}, doi = {10.4028/www.scientific.net/AMR.622-623.461}, pages = {461 -- 465}, year = {2012}, abstract = {Additive manufacturing (AM) of metal parts by using Selective Laser Melting (SLM) has become a powerful tool mostly in the area of automotive, aerospace engineering and others. Especially in the field of dentistry, jewelry and related branches that require individualized or even one-of-a-kind products, the direct digital manufacturing process opens up new ways of design and manufacturing. In these fields, mostly small and medium sized businesses (SME) are operating which do not have sufficient human and economic resources to invest in this technology. But to stay competitive, the application of AM can be regarded as a necessity. In this situation a new desktop machine (Realizer SLM 50) was introduced that cost about 1/3 of a shop floor SLM machine and promises small quality parts. To find out whether the machine really is an alternative for SMEs the University of Applied Science, Aachen, Germany, designed, build and optimized typical parts from the dentistry and the jewelry branches using CoCr and silver material, the latter being new with this application. The paper describes the SLM procedure and how to find and optimize the most important parameters. The test is accompanied by digital simulation in order to verify the build parameters and to plan future builds. The procedure is shown as well as the resulting parts made from CoCr and silver material.}, language = {en} } @article{LeidingerNoistenWollert2012, author = {Leidinger, Rafael and Noisten, Thomas and Wollert, J{\"o}rg}, title = {Realtime automation networks in moVing industrial environments}, series = {Journal of systemics, cybernetics and informatics}, volume = {Vol. 10}, journal = {Journal of systemics, cybernetics and informatics}, number = {Iss. 2}, publisher = {IIIC}, address = {Orlando}, issn = {1690-4532}, pages = {52 -- 56}, year = {2012}, abstract = {The radio-based wireless data communication has made the realization of new technical solutions possible in many fields of the automation technology (AT). For about ten years, a constant disproportionate growth of wireless technologies can be observed in the automation technology. However, it shows that especially for the AT, conventional technologies of office automation are unsuitable and/or not manageable. The employment of mobile services in the industrial automation technology has the potential of significant cost and time savings. This leads to an increased productivity in various fields of the AT, for example in the factory and process automation or in production logistics. In this paper technologies and solutions for an automation-suited supply of mobile wireless services will be introduced under the criteria of real time suitability, IT-security and service orientation. Emphasis will be put on the investigation and development of wireless convergence layers for different radio technologies, on the central provision of support services for an easy-to-use, central, backup enabled management of combined wired / wireless networks and on the study on integrability in a Profinet real-time Ethernet network.}, language = {en} } @article{Gartzen2011, author = {Gartzen, Johannes}, title = {Sp{\"a}tes Aufwachen aus dem Dornr{\"o}schenschlaf: Ohne Energie l{\"a}uft nichts}, series = {Aachener Nachrichten (2011)}, journal = {Aachener Nachrichten (2011)}, publisher = {Zeitungsverl. Aachen}, address = {Aachen}, pages = {22}, year = {2011}, language = {de} } @article{KallweitKorculaninFroehligetal.2011, author = {Kallweit, Stephan and Korculanin, O. and Fr{\"o}hlig, F. and Gabi, M. and Mattern, P.}, title = {Photogrammetrische Rekonstruktion von Partikelpositionen mittels R{\"u}ckprojektion f{\"u}r 3D-PIV}, series = {Lasermethoden in der Str{\"o}mungsmesstechnik : 19. Fachtagung, 6. - 8. September 2011, Ilmenau ; [Tagungsband enth{\"a}lt ... Beitr{\"a}ge, die anl{\"a}sslich der 19. Fachtagaung "Lasermethoden in der Str{\"o}mungsmesstechnik" ... vorgetragen und diskutiert wurden] / veranst. von der Deutschen Gesellschaft f{\"u}r Laser-Anemometrie GALA e.V. Hrsg. A. Thess...}, journal = {Lasermethoden in der Str{\"o}mungsmesstechnik : 19. Fachtagung, 6. - 8. September 2011, Ilmenau ; [Tagungsband enth{\"a}lt ... Beitr{\"a}ge, die anl{\"a}sslich der 19. Fachtagaung "Lasermethoden in der Str{\"o}mungsmesstechnik" ... vorgetragen und diskutiert wurden] / veranst. von der Deutschen Gesellschaft f{\"u}r Laser-Anemometrie GALA e.V. Hrsg. A. Thess...}, publisher = {Dt. Ges. f{\"u}r Laser-AnemometrieGALA e. V.}, address = {Karlsruhe}, isbn = {978-3-9805613-7-2}, pages = {28/1 -- 28/6}, year = {2011}, language = {de} } @article{MukherjeeRamazaniYangetal.2011, author = {Mukherjee, Krishnendu and Ramazani, Ali and Yang, Li and Prahl, Ulrich and Bleck, Wolfgang and Reisgen, Uwe and Schleser, Markus and Abdurakhmanov, Aydemir}, title = {Characterization of gas metal arc welded hot rolled DP600 steel}, series = {Steel research international}, volume = {Vol. 82}, journal = {Steel research international}, number = {Iss. 12}, publisher = {Wiley}, address = {Weinheim}, issn = {1869-344X (E-Book); 1611-3683 (Print)}, pages = {1408 -- 1416}, year = {2011}, language = {en} } @article{GlowaniaGriesSchoeneetal.2011, author = {Glowania, Michael and Gries, Thomas and Schoene, Jens and Schleser, Markus and Reisgen, Uwe}, title = {Innovative coating technology for textile reinforcements of concrete applications}, series = {13th International Congress on Polymers in Concrete : 10 - 12 February 2010, Funchal, Madeira, Portugal.(Key engineering materials. Vol. 466)}, journal = {13th International Congress on Polymers in Concrete : 10 - 12 February 2010, Funchal, Madeira, Portugal.(Key engineering materials. Vol. 466)}, publisher = {Trans Tech Publications}, address = {B{\"a}ch}, organization = {International Congress Polymers in Concrete <13, 2010, Funchal, Madeira>}, isbn = {978-3-03785-008-4}, issn = {1013-9826 (E-Journal) ; 0252-1059 (Print)}, pages = {167 -- 173}, year = {2011}, language = {en} } @article{ReisgenSchleserMokrovetal.2011, author = {Reisgen, Uwe and Schleser, Markus and Mokrov, Oleg and Ahmed, Essam}, title = {Numerical and experimental investigation of tensile behavior of laser beam welded TRIP700 steel}, series = {ISIJ international}, volume = {Vol. 51}, journal = {ISIJ international}, number = {No. 3}, publisher = {ISIJ}, address = {Tōkyō}, organization = {Iron and Steel Institute of Japan (ISIJ)}, issn = {1347-5460 (E-Journal); 0915-1559 (Print)}, pages = {429 -- 434}, year = {2011}, language = {en} } @article{ReisgenSchleserHarmsetal.2011, author = {Reisgen, Uwe and Schleser, Markus and Harms, Alexander and Schiebahn, Alexander and Naumov, Andreas}, title = {Erweiterung des Parameterfelds zum R{\"u}hrreibschweißen mittels konduktiver Unterst{\"u}tzung}, series = {Schweissen und Schneiden : Fachzeitschrift f{\"u}r Schweißen und verwandte Verfahren}, volume = {Bd. 63}, journal = {Schweissen und Schneiden : Fachzeitschrift f{\"u}r Schweißen und verwandte Verfahren}, number = {H. 12}, publisher = {DVS-Media GmbH}, address = {D{\"u}sseldorf}, issn = {0036-7184}, pages = {710 -- 714}, year = {2011}, language = {de} } @article{ReisgenSchleserHarmsetal.2011, author = {Reisgen, Uwe and Schleser, Markus and Harms, Alexander and Schiebahn, Alexander and Thiele, Regina}, title = {Elektromobilit{\"a}t - Herausforderungen an die F{\"u}getechnik}, series = {mobilit{\"a}t morgen - Magazin zu Mobilit{\"a}t und Elektromobilit{\"a}t}, volume = {Jg. 1}, journal = {mobilit{\"a}t morgen - Magazin zu Mobilit{\"a}t und Elektromobilit{\"a}t}, number = {Nr. 2}, editor = {Kampker, Achim}, pages = {16 -- 17}, year = {2011}, language = {de} } @article{RoesnerScheikOlowinskyetal.2011, author = {Roesner, Andreas and Scheik, Sven and Olowinsky, Alexander and Gillner, Arnold and Propawe, Reinhart and Schleser, Markus and Reisgen, Uwe}, title = {Innovative approach of joining hybrid components}, series = {Journal of laser applications}, volume = {Vol. 23}, journal = {Journal of laser applications}, number = {Iss. 3}, publisher = {Laser Institute of America}, address = {Orlando, Fla.}, issn = {1042-346X}, pages = {32007}, year = {2011}, language = {en} } @article{RoesnerScheikOlowinskyetal.2011, author = {Roesner, Andreas and Scheik, Sven and Olowinsky, Alexander and Gillner, Arnold and Reisgen, Uwe and Schleser, Markus}, title = {Laser assisted joining of plastic metal hybrids}, series = {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)}, journal = {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)}, publisher = {Elsevier}, address = {Amsterdam}, organization = {International WLT Conference on Lasers in Manufacturing <6, M{\"u}nchen, 2011>}, issn = {1875-3892 (E-Journal); 1875-3884 (Print)}, pages = {370 -- 377}, year = {2011}, language = {en} } @article{ReisgenSchleserMokrovetal.2011, author = {Reisgen, Uwe and Schleser, Markus and Mokrov, Oleg and Zabirov, Alexander}, title = {Virtual welding equipment for simulation of GMAW processes with integration of power source regulation}, series = {Frontiers of materials science}, volume = {Vol. 5}, journal = {Frontiers of materials science}, number = {Iss. 2}, publisher = {Springer}, address = {Berlin}, issn = {2095-0268 (E-Journal); 2095-025X (Print)}, pages = {79 -- 89}, year = {2011}, language = {en} } @article{GebhardtSchmidtHoetteretal.2010, author = {Gebhardt, Andreas and Schmidt, Frank-Michael and H{\"o}tter, Jan-Steffen and Sokalla, Wolfgang and Sokalla, Patrick}, title = {Additive Manufacturing by selective laser melting the realizer desktop machine and its application for the dental industry}, series = {Physics Procedia}, volume = {5}, journal = {Physics Procedia}, number = {2}, isbn = {1875-3892}, pages = {543 -- 549}, year = {2010}, language = {en} } @article{WollertLeidinger2010, author = {Wollert, J{\"o}rg and Leidinger, Rafael}, title = {Automation trifft Automotive : SPS in der Fahrzeugtechnik}, series = {Elektronik automotive : Magazin f{\"u}r Entwicklungen in der Kfz-Elektronik und Telematik}, journal = {Elektronik automotive : Magazin f{\"u}r Entwicklungen in der Kfz-Elektronik und Telematik}, number = {4/5}, publisher = {WEKA Fachmedien}, address = {Haar}, issn = {1614-0125}, pages = {44 -- 48}, year = {2010}, abstract = {Eine SPS im Kraftfahrzeug? Das geht ja gar nicht - da gibt es doch all die Hersteller f{\"u}r Kfz-Steuerger{\"a}te, die konfigurierbare Hardware anbieten. Im Prinzip ja, aber leider sind gerade die Sensoren oder Aktoren nicht ansteuerbar, die der Entwickler genau f{\"u}r sein aktuelles Projekt ben{\"o}tigt. Dieser Beitrag gibt einen kleinen Einblick in neue M{\"o}glichkeiten des Rapid Prototyping f{\"u}r mechatronische Systeme auf der Basis von Speicherprogrammierbaren Steuerungen (SPS).}, language = {de} } @article{ReisgenSchleserMokrovetal.2010, author = {Reisgen, Uwe and Schleser, Markus and Mokrov, Oleg and Ahmed, Essam}, title = {Uni- and bi-axial deformation behavior of laser welded advanced high strength steel sheets}, series = {Journal of materials processing technology}, volume = {210}, journal = {Journal of materials processing technology}, number = {15}, publisher = {Elsevier}, address = {Amsterdam}, issn = {0924-0136}, doi = {http10.1016/j.jmatprotec.2010.08.003}, pages = {2188 -- 2196}, year = {2010}, abstract = {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.}, language = {en} } @article{ReisgenSchleserJerabeketal.2010, author = {Reisgen, Uwe and Schleser, Markus and Jerabek, Jakub and Chudoba, Rostislav}, title = {Messung der Strahlqualit{\"a}t einer Elektronenstrahlanlage in Umgebungsatmosph{\"a}re}, series = {Materialwissenschaft und Werkstofftechnik}, volume = {41}, journal = {Materialwissenschaft und Werkstofftechnik}, number = {1}, publisher = {Wiley-VCH}, address = {Weinheim}, issn = {1521-4052}, pages = {45 -- 52}, year = {2010}, abstract = {In den letzten Jahrzehnten hat das Elektronenstrahlschweißen, das bereits im gr{\"o}ßeren Maßstab verwendet wird, seine F{\"a}higkeit als qualitatives Werkzeug f{\"u}r 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 Atmosph{\"a}rendruck arbeiten kann. Im Hinblick auf die reproduzierbare Qualit{\"a}t, 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 Strahlkenngr{\"o}ßen wie des Strahldurchmessers und der Leistungsdichteverteilung kann eine Aussage {\"u}ber die sich ausbildende Schweißnaht sowie die Schweißbaddynamik getroffen werden. Messungen der Strahlkenngr{\"o}ßen im Prozess erlauben insbesondere die Untersuchung von Humping-Effekten. In diesem Beitrag wird der Prozess der Elektronenstrahlvermessung unter atmosph{\"a}rischen Bedingungen beschrieben. Es wird zudem die Abh{\"a}ngigkeit der Elektronenstrahlcharakteristika von den verschiedenen Prozessparametern dargestellt.}, language = {de} } @article{MukherjeePrahlBlecketal.2010, author = {Mukherjee, Krishnendu and Prahl, Ulrich and Bleck, Wolfgang and Reisgen, Uwe and Schleser, Markus and Abdurakhmanov, Aydemir}, title = {Characterization and modelling techniques for gas metal arc welding of DP 600 sheet steels}, series = {Materialwissenschaft und Werkstofftechnik}, volume = {41}, journal = {Materialwissenschaft und Werkstofftechnik}, number = {11}, publisher = {Wiley-VCH}, address = {Weinheim}, issn = {1521-4052}, doi = {10.1002/mawe.201000692}, pages = {972 -- 983}, year = {2010}, abstract = {The objectives of the present work are to characterize the Gas Metal Arc Welding process of DP 600 sheet steel and to summarize the modelling techniques. The time-temperature evolution during the welding cycle was measured experimentally and modelled with the softwaretool SimWeld. To model the phase transformations during the welding cycle dilatometer tests were done to quantify the parameters for phase field modelling by MICRESS®. The important input parameters are interface mobility, nucleation density, etc. A contribution was made to include austenite to bainite transformation in MICRESS®. This is useful to predict the microstructure in the fast cooling segments. The phase transformation model is capable to predict the microstructure along the heating and cooling cycles of welding. Tensile tests have shown the evidence of failure at the heat affected zone, which has the ferrite-tempered martensite microstructure.}, language = {en} } @article{ReisgenSchleserMokrovetal.2010, author = {Reisgen, Uwe and Schleser, Markus and Mokrov, Oleg and Ahmed, Essam}, title = {Shielding gas influences on laser weldability of tailored blanks of advanced automotive steels}, series = {Applied surface science}, volume = {257}, journal = {Applied surface science}, number = {5}, publisher = {Elsevier}, address = {Amsterdam}, issn = {0169-4332 (E-Journal); 0169-4332 (Print)}, doi = {10.1016/j.apsusc.2010.08.042}, pages = {1401 -- 1406}, year = {2010}, abstract = {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.}, language = {en} } @article{AhmedReisgenSchleseretal.2010, author = {Ahmed, Essam and Reisgen, Uwe and Schleser, Markus and Mokrov, Oleg}, title = {On formability of tailor laser welded blanks of DP/TRIP steel sheets}, series = {Science and technology of welding and joining}, volume = {15}, journal = {Science and technology of welding and joining}, number = {5}, publisher = {Maney}, address = {Leeds}, issn = {1743-2936}, doi = {10.1179/136217110X12731414739754}, pages = {337 -- 342}, year = {2010}, abstract = {This paper aims to evaluate the formability of tailor welded blanks of dual phase (DP600)/transformation induced plasticity (TRIP700) steel sheets. In this work, bead on plate butt joints of 2·5 mm DP600 and 1·2 mm TRIP700 steel sheets were performed using CO2 laser beam welding. Microhardness measurements and transverse tensile testing were carried out to characterise the welds. The formability of base metals and welds were investigated by standard Erichsen test. In a perpendicular tensile test to the weld line, all specimens were fractured at the TRIP base metal, and the strengths were somewhat higher than those of base metal. There was a significant reduction in formability caused by welding of the DP600/TRIP700 steel sheets, and the formability increased with increasing welding speed.}, language = {en} } @article{HaselgruberMautnerThiele2010, author = {Haselgruber, Nikolaus and Mautner, Karin and Thiele, Jan}, title = {Usage Space Analysis for Reliability Testing}, series = {Quality and Reliability Engineering International}, volume = {26}, journal = {Quality and Reliability Engineering International}, number = {8}, publisher = {Wiley}, address = {New York}, issn = {1099-1638}, doi = {10.1002/qre.1155}, pages = {877 -- 885}, year = {2010}, abstract = {During the development process of a complex technical product, one widely used and important technique is accelerated testing where the applied stress on a component is chosen to exceed the reference stress, i.e. the stress encountered in field operation, in order to reduce the time to failure. For that, the reference stress has to be known. Since a complex technical product may fail regarding numerous failure modes, stress in general is highly dimensional rather than scalar. In addition, customers use their products individually, i.e. field operation should be described by a distribution rather than by one scalar stress value. In this paper, a way to span the customer usage space is shown. It allows the identification of worst case reference stress profiles in significantly reduced dimensions with minimal loss of information. The application example shows that even for a complex product like a combustion engine, stress information can be compressed significantly. With low measurement effort it turned out that only three reference stress cycles were sufficient to cover a broad range of customer stress variety.}, language = {en} } @article{EnningBaier2009, author = {Enning, Manfred and Baier, M.}, title = {Energetic and operational use of FlexCargoRail freight wagons in the single wagon load traffic / Baier, M. ; Enning, M.}, series = {Towards zero emission : EVS 24, the 24th International Battery, Hybrid and Fuel Cell Electric Vehicle Symposium \& Exhibition, Stavanger, Norway, May 13 - 16, 2009 ; symposium proceedings / organised by AVERE ... Robert St{\"u}ssi [Hrsg.]}, journal = {Towards zero emission : EVS 24, the 24th International Battery, Hybrid and Fuel Cell Electric Vehicle Symposium \& Exhibition, Stavanger, Norway, May 13 - 16, 2009 ; symposium proceedings / organised by AVERE ... Robert St{\"u}ssi [Hrsg.]}, address = {Stavanger}, pages = {CD-Rom}, year = {2009}, language = {en} } @article{EnningBaierDaniel2009, author = {Enning, Manfred and Baier, M. and Daniel, A. F.}, title = {Fahrzeugtechnische Machbarkeitsstudie eines selbstangetriebenen G{\"u}terwagens f{\"u}r das System FlexCargoRail / Baier, M. ; Daniel, A. F. ; Enning, M.}, series = {ZEVrail : Glasers Annalen ; Zeitschrift f{\"u}r das gesamte System Bahn. 133 (2009), H. 1-2}, journal = {ZEVrail : Glasers Annalen ; Zeitschrift f{\"u}r das gesamte System Bahn. 133 (2009), H. 1-2}, publisher = {Siemens}, address = {Berlin}, isbn = {1618-8330}, pages = {52 -- 58}, year = {2009}, language = {de} } @article{EnningDollsBrunberg2009, author = {Enning, Manfred and Dolls, S. and Brunberg, A.}, title = {Selbsteinstellverfahren f{\"u}r Temperiervorrichtungen mit Außenverrohrung / Dolls, S. ; Enning, M. ; Brunberg, A. ; Abel, D.}, series = {Automation 2009 : Automatisierungskongress in Deutschland ; Kongress Baden-Baden, 16. und 17. Juni 2009 / VDI-VDE-Gesellschaft Mess- und Automatisierungstechnik}, journal = {Automation 2009 : Automatisierungskongress in Deutschland ; Kongress Baden-Baden, 16. und 17. Juni 2009 / VDI-VDE-Gesellschaft Mess- und Automatisierungstechnik}, publisher = {VDI-Verl.}, address = {D{\"u}sseldorf}, isbn = {978-3-18-092067-2}, pages = {429 -- 432}, year = {2009}, language = {de} } @article{StarkeAhlbehrendtBischoffetal.2009, author = {Starke, G{\"u}nther and Ahlbehrendt, Norbert and Bischoff, Rainer and Melzer, Harald and Sieber, Sven and Senk, Burkhard and Kramarczyk, Peter}, title = {RoboTOOL. Technologien f{\"u}r den ortsflexiblen Einsatz von Robotern bei tempor{\"a}ren Arbeitsaufgaben in der Fertigung}, series = {wt Werkstattstechnik online}, volume = {Bd. 99}, journal = {wt Werkstattstechnik online}, number = {H. 9}, issn = {1436-4980}, pages = {661 -- 670}, year = {2009}, language = {de} }