@inproceedings{BrandPetzTutschetal., author = {Brand, M. and Petz, M. and Tutsch, R. and Wohlfahrt, Helmut and Michailov, Vesselin}, title = {Numerische Simulation und Verifikation des Bauteilverzugs beim Schweißen unter Verwendung optischer Feldmeßmethoden}, series = {Conference proceedings, 21st CAD-FEM Users' Meeting 2003, International Congress on FEM Technology, 12. - 14. November 2003, im Hotel Dorint Sanssouci Berlin, Potsdam}, booktitle = {Conference proceedings, 21st CAD-FEM Users' Meeting 2003, International Congress on FEM Technology, 12. - 14. November 2003, im Hotel Dorint Sanssouci Berlin, Potsdam}, publisher = {CAD-FEM GmbH}, address = {Grafing bei M{\"u}nchen}, isbn = {3-937523-00-6}, language = {de} } @misc{MichailovStadtaus, author = {Michailov, Vesselin and Stadtaus, Marc}, title = {Einige Probleme der FE-Simulation zur Wasserstoff- und Stickstoffverteilung beim Schweißen}, series = {Zeitschrift f{\"u}r Metallkunde}, volume = {92}, journal = {Zeitschrift f{\"u}r Metallkunde}, number = {3}, issn = {0044-3093}, pages = {247 -- 252}, language = {de} } @misc{ZhangDoynovWolfetal., author = {Zhang, Wei and Doynov, Nikolay and Wolf, Matthias and Dreibati, Ossama and Ossenbrink, Ralf and Michailov, Vesselin}, title = {Investigation of the Thermal Shock Behavior of Ceramic Using a Combination of Experimental Testing and FE-Simulation Methods}, series = {Advanced engineering materials}, volume = {15}, journal = {Advanced engineering materials}, number = {6}, issn = {1527-2648}, doi = {10.1002/adem.201200241}, pages = {480 -- 484}, abstract = {Thermal shock behavior of ceramics plays a decisive role in their broad industrial applications. For enhanced understanding of damage and failure mechanism under thermal shock loading, in the present work, a combination of experimental testing and numerical simulation methods has been used. The thermal shock behavior of the alumina (99.7\%) disk samples has been investigated by using a plasma test stand: the bottom of the ceramic disks were locally heated in the center by plasma beam; during the heat treatment the temperature distribution at the top of the sample was recorded with a thermographic system. To characterize the thermal shock resistance, a thermomechanical simulation was subsequently carried out. It calculates the temperature and stress distribution within the ceramic disks. The calculated critical thermal tension stresses are reported, which led to the failure of the ceramic disks under thermal shock loading. The effect of the sample thickness on the temperature and stress distribution is presented. Compared with the experimental results the simulated results show excellent agreement. As conclusion, it is possible to determine the thermal shock behavior of ceramic materials by the combination of experimental testing and numerical simulation.}, language = {en} } @inproceedings{OssenbrinkMichailov, author = {Ossenbrink, Ralf and Michailov, Vesselin}, title = {Vorhersage der H{\"a}rteverteilung beim Schweißen mit Hilfe der numerischen Simulation}, series = {Conference proceedings, 21st CAD-FEM Users' Meeting 2003, International Congress on FEM Technology, 12. - 14. November 2003, im Hotel Dorint Sanssouci Berlin, Potsdam}, booktitle = {Conference proceedings, 21st CAD-FEM Users' Meeting 2003, International Congress on FEM Technology, 12. - 14. November 2003, im Hotel Dorint Sanssouci Berlin, Potsdam}, publisher = {CAD-FEM GmbH}, address = {Grafing bei M{\"u}nchen}, isbn = {3-937523-00-6}, language = {de} } @incollection{DoynovChristovMichailovetal., author = {Doynov, Nikolay and Christov, St. and Michailov, Vesselin and Wohlfahrt, Helmut}, title = {Finite Elements Simulation of Multipass Submerged Arc Welding}, series = {Mathematical Modelling of Weld Phenomena 6}, booktitle = {Mathematical Modelling of Weld Phenomena 6}, publisher = {Maney - IOM}, address = {London}, isbn = {978-1-902653-56-3}, pages = {651 -- 669}, language = {en} } @incollection{StadtausMichailovWohlfahrt, author = {Stadtaus, Marc and Michailov, Vesselin and Wohlfahrt, Helmut}, title = {Simulation of Weld Shape, Microstructure, Distortion and Residual Stresses for Laser Beam Welding}, series = {Mathematical Modelling of Weld Phenomena 6}, booktitle = {Mathematical Modelling of Weld Phenomena 6}, publisher = {Maney - IOM}, address = {London}, isbn = {978-1-902653-56-3}, pages = {419 -- 442}, language = {en} } @incollection{RethmeierStadtausMichailovetal., author = {Rethmeier, M. and Stadtaus, Marc and Michailov, Vesselin and Wohlfahrt, Helmut}, title = {Numerical Calculation of Temperature Load and Distortion during Welding of Circumferential Weld Seams}, series = {Mathematical Modelling of Weld Phenomena 6}, booktitle = {Mathematical Modelling of Weld Phenomena 6}, publisher = {Maney - IOM}, address = {London}, isbn = {978-1-902653-56-3}, pages = {685 -- 702}, language = {en} } @incollection{StadtausMichailovWohlfahrt, author = {Stadtaus, Marc and Michailov, Vesselin and Wohlfahrt, Helmut}, title = {Berechnung von Nahtgeometrie, Gef{\"u}ge, Verzug und Eigenspannungen beim Schmelzschweißen}, series = {Schweißen und Schneiden 2001}, booktitle = {Schweißen und Schneiden 2001}, publisher = {DVS Verlag}, address = {D{\"u}sseldorf}, isbn = {978-3-87155-674-6}, pages = {315 -- 321}, language = {de} } @incollection{RoehrsMichailovWohlfahrt, author = {R{\"o}hrs, K. and Michailov, Vesselin and Wohlfahrt, Helmut}, title = {Einfluss von Beimengungen zum Schutzgas beim Lichtbogenschweißen von Aluminiumwerkstoffen}, series = {Schweißen und Schneiden 2001}, booktitle = {Schweißen und Schneiden 2001}, publisher = {DVS Verlag}, address = {D{\"u}sseldorf}, isbn = {978-3-87155-674-6}, pages = {349 -- 354}, language = {de} } @inproceedings{KarkhinLevchenkoHomichetal., author = {Karkhin, Victor A. and Levchenko, A. M. and Homich, P. N. and Michailov, Vesselin}, title = {Computer-Aided Express Determination of Diffusible Hydrogen in Deposited Weld Metal}, series = {International Conference on Total Welding Management in Industrial Applications, 3rd JOIN Conference, Lappeenranta, August 21 - 24, 2007}, booktitle = {International Conference on Total Welding Management in Industrial Applications, 3rd JOIN Conference, Lappeenranta, August 21 - 24, 2007}, address = {Lappeenranta}, isbn = {978-952-214-413-3}, pages = {252 -- 262}, language = {en} } @misc{StadtausMichailovWohlfahrt, author = {Stadtaus, Marc and Michailov, Vesselin and Wohlfahrt, Helmut}, title = {Numerical calculation of the main factors on cold cracking}, series = {Materialwissenschaften und Werkstofftechnik}, volume = {34}, journal = {Materialwissenschaften und Werkstofftechnik}, number = {1}, issn = {0933-5137}, doi = {10.1002/mawe.200390007}, pages = {145 -- 151}, language = {en} } @inproceedings{OssenbrinkMichailovWohlfahrt, author = {Ossenbrink, Ralf and Michailov, Vesselin and Wohlfahrt, Helmut}, title = {Numerische Simulation der Eigenspannungen und des Bauteilverzugs beim Schweißen unter Ber{\"u}cksichtigung der zeitlichen und {\"o}rtlichen {\"A}nderung der Dehnrate}, series = {Internationale FEM-Technologietage, 20th CAD-FEM Users' Meeting, 9-11 Oktober 2002, Friedrichshafen}, booktitle = {Internationale FEM-Technologietage, 20th CAD-FEM Users' Meeting, 9-11 Oktober 2002, Friedrichshafen}, publisher = {CAD-FEM GmbH}, address = {Grafing bei M{\"u}nchen}, language = {de} } @misc{KornienkoOssenbrinkMichailov, author = {Kornienko, Elena and Ossenbrink, Ralf and Michailov, Vesselin}, title = {Corrosion resistance of zinc-coated structured sheet metals}, series = {Corrosion Science}, volume = {Vol. 69}, journal = {Corrosion Science}, issn = {0010-938X}, pages = {270 -- 280}, abstract = {The purpose of this study is to characterise the corrosion behaviour of zinc-coated sheet metals after a structuring process using the salt spray test. The investigated structured material is manufactured by hydroforming and has a periodic hexagonal geometry. The corrosion behaviour has been evaluated by estimating the development of the corrosion area and penetration depth. The results of the investigation show that the corrosion area is larger on the smooth sheet than on the structured sheet. The difference between the structured and smooth sheets is negligible with increasing exposure time. Furthermore, the reasons for the different corrosion behaviours are discussed.}, language = {en} } @inproceedings{OssenbrinkDoynovMichailov, author = {Ossenbrink, Ralf and Doynov, Nikolay and Michailov, Vesselin}, title = {Welding simulation of aluminium to steel joints by means of arc welding Processes}, series = {10th International Scientific and Technical Conference, Advanced metal materials and technologies (AMMT'2013), June 25-29, Saint Petersburg, 2013}, booktitle = {10th International Scientific and Technical Conference, Advanced metal materials and technologies (AMMT'2013), June 25-29, Saint Petersburg, 2013}, publisher = {Izdat. Polytechn. Univ.}, address = {Saint Petersburg, Russia}, pages = {523 -- 528}, abstract = {The object of the present work is the introduction of a welding simulation approach for aluminium to steel welded joints which are realised by short-arc welding. The study is carried out with special emphasis on the simulation of temperature field by means of conduction solution, on the applicability of different metallurgical models as well as the aspects of the mechanical simulation of the residual welding stresses and distortions. As result an approved heat source model is suggested and the calibration parameters are presented. For the modelling of the microstructure and corresponding thermomechanical material properties in the heat affected zone different material models are validated. They are used to simulate the welding residual stresses and distortions. Furthermore, the welding simulation of a real component as well as a simulation study of different welding scenarios is presented.}, language = {en} } @misc{VossMichailovDecker, author = {Voß, O. and Michailov, Vesselin and Decker, I.}, title = {Erweiterung der numerischen Schweißsimulation zur Untersuchung metallkundlicher Fragestellungen}, series = {Zeitschrift f{\"u}r Metallkunde}, volume = {92}, journal = {Zeitschrift f{\"u}r Metallkunde}, number = {3}, issn = {0044-3093}, pages = {293 -- 299}, language = {de} } @misc{ThomasMichailovWohlfahrt, author = {Thomas, Karl and Michailov, Vesselin and Wohlfahrt, Helmut}, title = {Z{\"a}higkeitsuntersuchungen an schmalen Verfahrenseinflusszonen pressstumpfgeschweißter St{\"a}hle}, series = {Schweißen und Schneiden}, volume = {52}, journal = {Schweißen und Schneiden}, number = {12}, pages = {734 -- 745}, language = {de} } @phdthesis{Stadtaus, author = {Stadtaus, Marc}, title = {FE-Simulation der Verteilung von Wasserstoff und Stickstoff in Schweißverbindungen}, publisher = {Shaker Verlag}, address = {Aachen}, isbn = {978-3-8440-2537-8}, pages = {184}, language = {de} } @incollection{OssenbrinkGenchevDoynov, author = {Ossenbrink, Ralf and Genchev, Gancho Vladimirov and Doynov, Nikolay}, title = {Simulation der Schweißeigenspannungen und des -verzuges unter Ber{\"u}cksichtigung der Gef{\"u}geumwandlungen mit dem STAAZ-Modell}, series = {Internationales Symposium Schweißtechnik - Verfahren, Werkstoffe, Simulation, Cottbus, 6. November 2013}, booktitle = {Internationales Symposium Schweißtechnik - Verfahren, Werkstoffe, Simulation, Cottbus, 6. November 2013}, editor = {Michailov, Vesselin}, publisher = {Shaker Verlag}, address = {Aachen}, isbn = {978-3-8440-2319-0}, pages = {149 -- 167}, abstract = {Die vorliegende Arbeit stellt das von Professor Michailov vorgeschlagene Spitzentemperatur-Austenitisierungs- Abk{\"u}hlzeit-Modell f{\"u}r die thermomechanische Schweißsimulation unter Ber{\"u}cksichtigung der Gef{\"u}geumwandlungen vor. Das Modell erfasst die f{\"u}r die Gef{\"u}geausbildung maßgebenden Temperaturzyklen durch seine drei so genannten STAAZ-Parameter: Spitzentemperatur, Austenitisierungs- und Abk{\"u}hlzeit. Die Korrelation dieser Temperaturzyklusparameter mit den thermomechanischen gef{\"u}geabh{\"a}ngigen Werkstoffeigenschaften erfolgt auf Grundlage einer empirischen Datenbasis. Mit der vorgenommenen Erweiterung zu Mehrmalig-(M-)STAAZ l{\"a}sst sich das aus einem vorgelagerten Temperaturzyklus entstandene Zwischengef{\"u}ge ber{\"u}cksichtigen.}, language = {de} } @phdthesis{Kornienko, author = {Kornienko, Elena}, title = {Einfluss der Beschichtung und des Schweißens auf das Korrosionsverhalten von strukturierten Blechen}, publisher = {Shaker}, address = {Aachen}, isbn = {978-3-8440-3087-7}, pages = {190}, language = {de} } @phdthesis{Sasse, author = {Sasse, Ina}, title = {Schneiden und Schweißen strukturierter Bleche mit Faserlaser}, publisher = {Shaker}, address = {Aachen}, isbn = {978-3-8440-3035-8}, pages = {XVIII, 131, 53}, language = {de} } @phdthesis{Kapp, author = {Kapp, Mirjam}, title = {Untersuchung der Einflussfaktoren auf die Kaltrissanf{\"a}lligkeit niedriglegierter St{\"a}hle beim Laserstrahlschweißen an zylindrischen Bauteilen}, publisher = {Shaker}, address = {Aachen}, isbn = {978-3-8440-3452-3}, pages = {166}, language = {de} } @phdthesis{Dreibati, author = {Dreibati, Ossama}, title = {Physical welding simulation of the cold crack susceptibility}, publisher = {Shaker}, address = {Aachen}, isbn = {978-3-8440-3133-1}, pages = {141}, language = {en} } @misc{OPUS4-14599, title = {Internationales Symposium Schweißtechnik - Verfahren, Werkstoffe, Simulation : 6. November 2013}, editor = {Michailov, Vesselin and Ossenbrink, Ralf and Doynov, Nikolay}, publisher = {Shaker}, address = {Aachen}, isbn = {978-3-8440-2319-0}, pages = {174}, language = {en} } @phdthesis{Stapelfeld, author = {Stapelfeld, Christoph}, title = {Vereinfachte Modelle zur Schweißverzugsberechnung}, publisher = {Shaker Verlag GmbH}, address = {Aachen}, isbn = {978-3-8440-4142-2}, pages = {234}, abstract = {Joining by means of welding has a vital importance in many sectors of industry. However, the uneven heating of the welded structure results in unwanted distortions, which has to be removed by cost-intensive after treatments. Knowing the welding distortions in an early stage of the product development cycle enables taking countermeasures or define after treatments, already in the product planning. The aim of this research study is the development and implementation of an analytic numerical hybrid model for the distortion calculation of large welded structures. The basis of the hybrid model is the analytical shrinkage force model, which is upgraded for modern welding processes and new materials. By means of experimental as well as numerical investigations, the instability of thin walled structures during welding is reviewed and a possibility for capturing is proposed. The linking of the analytical and the numerical method opens up the possibility for calculating the distortions caused by curved trajectories. To simplify the application of the hybrid model, a software will be programmed, including the complex mathematical approach of the shrinkage force model. It determines the mechanical loads, depending on the geometry of the welded structure, material data and weld parameters. The verification of the program as well as the coupling procedure is done on butt joints. The same welded structures are used for the investigation of the stability and the sensibility of the hybrid model afterwards. Finally the hybrid model will be applied to welded structures of different complexity and the results will be compared with experimental measurements. At the beginning butt and T-joints are determined, followed by the distortion calculation of a evaluation model made up of 8 welds. At the end an entire section of a ship deck, whereupon different elements are assembled by about 90 welds on a 20x16 meter large ground plate, is estimated.}, language = {de} } @misc{SasseSchleussOssenbrinketal., author = {Sasse, Ina and Schleuß, Leander and Ossenbrink, Ralf and Michailov, Vesselin}, title = {Joining of structured sheet metals - Remote laser beam welding in comparison with resistance spot welding}, series = {Welding and Cutting}, volume = {13}, journal = {Welding and Cutting}, number = {1}, pages = {43 -- 47}, abstract = {One main problem of thin-walled, large-area sheet components for lightweight construction solutions is the inadequate stiffness. One approach for a solution is provided by structured sheet metals which have an increased flexural stiffness due to three-dimensionally incorporated structures. The areas of application of the structured sheet metals (e.g. in subassemblies in automobile, rail vehicle and tank construction) necessitate adapted welding technologies. Since few systematic investigations have been conducted on structured sheet metals in the field of joining technology until now, there is a lack of knowledge about the further processing of these sheets by means of welding technology. The aims of the presented investigations are to make it possible to utilise these modern semi-finished products industrially using remote laser beam welding and to compare this with resistance spot welding. Both are important joining processes in the areas of applications interesting for structured sheet metals and thus constitute key technologies for industrial utilisation. Resistance spot welding has already been qualified for utilisation on structured sheet metals [1]. In addition, investigations were conducted into the remote laser beam welding of structured and flat sheets. These investigations encompass the possibilities of joining structured and flat joining members by means of remote laser beam welding as well as the assessment of the joint strength in tensile shear and peel tests. Thereafter, the results of the investigations are compared with the resistance spot welding of structured sheet metals and specific application recommendations are derived.}, language = {en} } @inproceedings{SasseSchleussOssenbrinketal., author = {Sasse, Ina and Schleuß, Leander and Ossenbrink, Ralf and Michailov, Vesselin}, title = {F{\"u}gen strukturierter Bleche - Remote-Laserstrahlschweißen im Vergleich zum Widerstandspunktschweißen}, series = {DVS Congress 2013, Große Schweißtechnische Tagung, DVS-Studentenkongress}, booktitle = {DVS Congress 2013, Große Schweißtechnische Tagung, DVS-Studentenkongress}, publisher = {DVS-Verlag}, address = {D{\"u}sseldorf}, isbn = {978-3-87155-614-2}, pages = {98 -- 103}, language = {de} } @misc{DreibatiOssenbrinkMichailov, author = {Dreibati, Ossama and Ossenbrink, Ralf and Michailov, Vesselin}, title = {Quantification of cold cracking parameters of high strength steels by physical simulation under welding conditions}, series = {Quarterly journal of the Japan Welding Society}, volume = {31}, journal = {Quarterly journal of the Japan Welding Society}, number = {4}, issn = {0288-4771}, doi = {10.2207/qjjws.31.148s}, pages = {148 -- 152}, abstract = {Cold cracks in welds are the result of the formation of brittle microstructure as martensite in the presence of diffusible hydrogen as well as of tensile stresses. Cold cracks occur when the combination of cold crack influence parameters (CCIP) overcomes a critical limit. In this study, critical combinations of CCIP were identified with an enhanced test procedure under welding conditions. The test is based on the physical simulation technique of heat affected zone (HAZ) and it is carried out using the test and simulation center Gleeble 3500. Thereby, laboratory special specimens are charged with hydrogen from pure hydrogen atmosphere in the initial stage of the test. Rigidly restraint specimen section is subjected to different weld temperature cycles. Through the thermal exposure, the desired microstructure of HAZ is set in the test zone of the restraint specimen section. A plastic deformation takes place owing to the prevented expansion during heating and contraction of the specimen during cooling. Consequently, compressive or tensile reactions stresses arise in the deformed zone. Cracked specimen represents a critical combination of the CCIP. The quantitative cold crack criterion separates the cold crack susceptible combinations from those non susceptible.}, language = {en} } @misc{MichailovDreibatiOssenbrinketal., author = {Michailov, Vesselin and Dreibati, Ossama and Ossenbrink, Ralf and Schweizer, Frank}, title = {Rechnergest{\"u}tzte Vorhersage der Kaltrissneigung laserstrahlgeschweißter Bauteile aus hochfesten St{\"a}hlen - Teil 1}, series = {Schweißen und Schneiden : Fachzeitschrift f{\"u}r Schweißen und verwandte Verfahren}, volume = {65}, journal = {Schweißen und Schneiden : Fachzeitschrift f{\"u}r Schweißen und verwandte Verfahren}, number = {11}, issn = {0036-7184}, pages = {776 -- 781}, language = {de} } @inproceedings{SchleussSeidlitzFritzscheetal., author = {Schleuß, Leander and Seidlitz, Holger and Fritzsche, Sebastian and Schulze, Marcus and Michailov, Vesselin and Schuhmann, Tilo}, title = {Gewichtsreduzierte Multi-Material-Bauweisen mit Organoblechen}, series = {Tagungsband, 15. Chemnitzer Textiltechnik-Tagung, Chemnitz, Germany, 31.05-01.06.2016}, booktitle = {Tagungsband, 15. Chemnitzer Textiltechnik-Tagung, Chemnitz, Germany, 31.05-01.06.2016}, publisher = {Technische Universit{\"a}t Chemnitz, Professur F{\"o}rdertechnik}, address = {Chemnitz}, isbn = {978-3-945479-06-3}, pages = {112 -- 119}, language = {de} } @techreport{SchleussBrobeckOssenbrinketal., author = {Schleuß, Leander and Brobeck, Andreas F. W. and Ossenbrink, Ralf and Polzin, Ralf and Michailov, Vesselin}, title = {Rollennahtschweißen strukturierter Feinbleche}, publisher = {BTU, Lehrstuhl F{\"u}ge- und Schweißtechnik}, address = {Cottbus-Senftenberg}, pages = {XV, 154}, abstract = {Strukturierte Bleche besitzen eine dreidimensionale Struktur aus regelm{\"a}ßig angeordneten Versteifungselementen, welche die Steifigkeit der Bleche global erh{\"o}hen. Neben der Steifigkeitserh{\"o}hung besitzen strukturierte Bleche eine vergr{\"o}ßerte Oberfl{\"a}che, ein ver{\"a}ndertes akustisches Verhalten sowie ein ansprechendes Design als positive Merkmale. Mit der Qualifizierung des Rollennahtschweißens f{\"u}r verzugsarme, mediendichte Schweißn{\"a}hte erschließen sich neue wichtige industrielle Anwendungen f{\"u}r strukturierte Bleche und den daraus hergestellten mehrschaligen Bauelementen (zwei strukturierte Bleche im Parallelstoß) mit Hohlr{\"a}umen zwischen den Blechen. Innovative Produktentwicklungen in der W{\"a}rmetechnik, im Transportwesen und im Bauwesen k{\"o}nnen mit strukturierten Blechen f{\"u}r Rekuperatoren, L{\"u}ftungsanlagen, W{\"a}rmeboxen, chemische Apparate, temperierbare Beh{\"a}lter sowie Fußbodenheizungen, K{\"u}hlr{\"a}ume, Klimakammern, Fassadenelemente oder L{\"a}rmschutzw{\"a}nde umgesetzt werden. Derzeit steht dazu kein geeignetes F{\"u}geverfahren zur Verf{\"u}gung, welches alle Anforderungen erf{\"u}llt. Das Rollennahtschweißen eignet sich, strukturierte Bleche so zu f{\"u}gen, dass sie den Anforderungen der zuk{\"u}nftigen Einsatzbereiche entsprechen unter Erhalt der positiven Eigenschaften. In diesem Projekt wurden strukturierte Einzelbleche und der aus ihnen gefertigten mehrschaligen Bauelemente mit dem Rollennahtschweißen gef{\"u}gt. Zur Herstellung der mehrschaligen Bauelemente wurden Rollpunktn{\"a}hte genutzt, welche strukturerhaltend hergestellt wurden. Dazu sind neuartige Rollennahtelektroden entwickelt, gefertigt und erprobt worden. Die notwendigen Schweißparameter zum strukturerhaltenden Schweißen und zum Schweißen mit Verformung der Struktur wurden in schweißbereichsdiagrammen dokumentiert und die Verbindungseigenschaften durch Zugversuche und Metallografie qualifiziert. F{\"u}r die genannten Anwendungsbereiche wurden Dichtn{\"a}hte an den Randbereichen der Bleche hergestellt. Durch die {\"U}berpr{\"u}fung der Dichtheit, der Druck- und Korrosionsbest{\"a}ndigkeit wurden die mehrschaligen Bauelemente f{\"u}r m{\"o}gliche Anwender qualifiziert. F{\"u}r die durchgef{\"u}hrten Recherchen und Untersuchungen wurde ein wissenschaftlicher Mitarbeiter in Vollzeit besch{\"a}ftigt und durch eine studentische Hilfskraft, sowie einen Techniker unterst{\"u}tzt. Die geleistete Arbeit entspricht im vollen Umfang dem begutachteten und bewilligten Antrag und war f{\"u}r die Durchf{\"u}hrung des Vorhabens notwendig und angemessen.}, language = {de} } @inproceedings{SchleussBrobeckOssenbrinketal., author = {Schleuß, Leander and Brobeck, Andreas F. W. and Ossenbrink, Ralf and Polzin, Ralf and Michailov, Vesselin}, title = {Neuartige Elektroden zum Rollennahtschweißen mit nichtlinearem Schweißpfad}, series = {Große Schweißtechnische Tagung, 15.-17.09.15}, booktitle = {Große Schweißtechnische Tagung, 15.-17.09.15}, publisher = {DVS Media}, address = {D{\"u}sseldorf}, isbn = {978-3-945023-46-4}, pages = {185 -- 190}, abstract = {Beim Rollennahtschweißen von Blechen mit eingebrachten Versteifungselementen wie Sicken oder regelm{\"a}ßig angeordneten Strukturen f{\"u}hren lineare Schweißpfade unter Verwendung klassischer Rollenelektroden zur teilweisen bzw. vollst{\"a}ndigen Einebnung dieser Versteifungselemente. Dadurch kann die positive Wirkung der Versteifungselemente reduziert bzw. vollst{\"a}ndig aufgehoben werden. Somit m{\"u}ssen neue Wege f{\"u}r das Rollennahtschweißen von gesickten oder strukturierten Blechen erarbeitet werden. Es wurden zwei neuartige Elektroden mit ver{\"a}nderten Geometrien an den Kontaktfl{\"a}chen entwickelt, welche die Topologie der Bleche ber{\"u}cksichtigen und eine Einebnung vermeiden. Eine der Elektroden besitzt eine periodisch unterbrochene Kontaktfl{\"a}che, die zweite eine laterale Profilierung mit in Schweißrichtung nichtlinearer Form der Kontaktfl{\"a}che. Das Verhalten beim Schweißen wurde durch Schweißversuche bestimmt. Es wurden Schweißbereichsdiagramme bzw. Prozessfenster abgeleitet. Die Verbindungseigenschaften wurden durch Metallografie-, Festigkeits-, Druck- und Dichtheitsuntersuchungen validiert. Als Vergleich und Referenz dienen Schweißuntersuchungen mit konventionellen Rollennahtelektroden. Die geschweißten Bleche haben Wabenstrukturen als regelm{\"a}ßig angeordnete Versteifungselemente mit unterschiedlichen Elementtiefen. Diese Bleche finden vorrangig Anwendung im Fahrzeugbau, in der Investitionsg{\"u}terindustrie und im Bauwesen. Aufgrund dieser Branchen und f{\"u}r zuk{\"u}nftige Anwendungen im W{\"a}rmetauscher- und Beh{\"a}lterbau sowie zur Ermittlung grundlegender Kenntnisse wurden die Untersuchungen an Werkstoffqualit{\"a}ten DC04 und 1.4301 mit Blechdicken von 0,5 mm und 0,7 mm durchgef{\"u}hrt. Die Untersuchungsergebnisse zeigen Unterschiede bei den Prozessparametern und der Auspr{\"a}gung der Verbindung in Abh{\"a}ngigkeit von der geschweißten Struktur, dem ausgew{\"a}hlten Schweißpfad und des geschweißten Werkstoffes gegen{\"u}ber den Referenzschweißungen. Eine anschließende Optimierung f{\"u}hrte zu einer vergleichbar guten Schweißnahtqualit{\"a}t sowohl bei Erhalt der Versteifungselemente mit den neuen Elektroden als auch bei deren Einebnung mit konventionellen Elektroden in Referenz zu Schweißuntersuchungen am ebenen Blech.}, language = {de} } @inproceedings{SchleussBrobeckOssenbrinketal., author = {Schleuß, Leander and Brobeck, Andreas F. W. and Ossenbrink, Ralf and Polzin, Ralf and Michailov, Vesselin}, title = {Rollennahtschweißen strukturierter Bleche mit neuartigen Elektroden}, series = {Widerstandsschweißen, 23. Sondertagung in Duisburg am 29. und 30. Juni 2016}, booktitle = {Widerstandsschweißen, 23. Sondertagung in Duisburg am 29. und 30. Juni 2016}, publisher = {DVS Media GmbH}, address = {D{\"u}sseldorf}, isbn = {978-3-945023-75-4}, pages = {230 -- 240}, abstract = {Bleche mit regelm{\"a}ßig angeordneten steifigkeitserh{\"o}henden Strukturen werden zunehmend in Kon-struktionen zur Erh{\"o}hung der Steifigkeit d{\"u}nner Bleche bzw. von kompletten Bauteilen verwendet. Damit diese Bauteile wirtschaftlich verarbeitet werden k{\"o}nnen, bietet das Rollennahtschweißen mit seinen hohen Prozessgeschwindigkeiten und ohne notwendigen Einsatz von Zusatzwerkstoffen bzw. Schweißhilfsstoffen eine kosteng{\"u}nstige Alternative zu anderen Verfahren. Beim Rollennahtschweißen strukturierter Bleche f{\"u}hren jedoch klassische Rollennahtelektroden zur teilweisen bzw. vollst{\"a}ndigen Einebnung der Versteifungselemente, sodass deren positive Wirkung reduziert bzw. vollst{\"a}ndig auf-gehoben werden kann. Die geschweißten Bleche haben Wabenstrukturen mit unterschiedlichen Elementtiefen als regelm{\"a}ßig angeordnete Versteifungselemente. Die Bleche finden vorrangig Anwendung im Fahrzeugbau und im Bauwesen. Aufgrund dieser Branchen und f{\"u}r zuk{\"u}nftige Anwendungen im W{\"a}rmetauscher- und Beh{\"a}l-terbau wurden die Untersuchungen an Werkstoffqualit{\"a}ten DC04 und X5CrNi 18-10 mit Blechdicken von 0,5 mm und 0,7 mm durchgef{\"u}hrt. Die entwickelten neuartigen Elektroden ber{\"u}cksichtigen die Topologie der Bleche, um eine Einebnung der strukturierten Bleche zu vermeiden. Daher wurden Elektroden mit ver{\"a}nderten Geometrien an den Elektrodenarbeitsfl{\"a}chen gestaltet. Eine der Elektroden besitzt eine periodisch unterbrochene und die zweite eine laterale Profilierung mit in Schweißrichtung nichtlinearer Form der Elektrodenarbeitsfl{\"a}che. Das Verhalten beim Schweißen wurde in Schweißversuchen bestimmt und Schweißbereichsdiagram-me bzw. Prozessfenster abgeleitet. Die Verbindungseigenschaften wurden durch Metallografie-, Fes-tigkeits-, Druck- und Dichtheitsuntersuchungen validiert. Als Vergleich und Referenz dienen Schweiß-untersuchungen mit konventionellen Rollennahtelektroden. Die Untersuchungsergebnisse zeigen Unterschiede bei den Prozessparametern und der Auspr{\"a}gung der Verbindung in Abh{\"a}ngigkeit von der geschweißten Struktur, dem ausgew{\"a}hlten Schweißpfad und des geschweißten Werkstoffes gegen{\"u}ber den Referenzschweißungen. Eine anschließende Optimie-rung f{\"u}hrte zu einer vergleichbar guten Schweißnahtqualit{\"a}t sowohl bei Erhalt der Versteifungselemen-te mit den neuen Elektroden als auch bei deren Einebnung mit konventionellen Elektroden in Referenz zu Schweißuntersuchungen am ebenen Blech. Anschließend wurde ein Vergleich der Verbindungsfestigkeiten mit dem Widerstandspunktschweißen und dem Metall-Aktivgas-Schweißen durchgef{\"u}hrt.}, language = {de} } @inproceedings{SchleussSpringerZoekeetal., author = {Schleuß, Leander and Springer, Katrin and Zoeke, J{\"o}rg and Ossenbrink, Ralf and Michailov, Vesselin}, title = {Qualifizierung von w{\"a}rmearmen MSG-Schweißverfahren f{\"u}r Leichtbaukonstruktionen mit strukturierten Halbzeugen}, series = {Internationaler Fachkongress der Schweiß- und Verbindungstechnik Join-Ex 2012 Wien, 10. + 11. Oktober 2012, Congress Center der Messe Wien}, booktitle = {Internationaler Fachkongress der Schweiß- und Verbindungstechnik Join-Ex 2012 Wien, 10. + 11. Oktober 2012, Congress Center der Messe Wien}, publisher = {Schweißtechnische Zentralanstalt e.V.}, address = {Wien}, pages = {75 -- 83}, language = {de} } @misc{KazakSchleussOssenbrinketal., author = {Kazak, Fedor and Schleuß, Leander and Ossenbrink, Ralf and Michailov, Vesselin and Weiß, Sabine}, title = {Particularities of testing structured sheet metals in 3-point bending tests}, series = {Materials Testing}, volume = {58}, journal = {Materials Testing}, number = {6}, issn = {0025-5300}, doi = {10.3139/120.110883}, pages = {495 -- 500}, abstract = {Thin sheet metals from deep drawing steel DC04 are very often used in the production of car body and case parts. Quality improvement of sheet metal components by new constructive solutions (structuring) as well as adapted joining technology is going on. Structured sheet metals differ from each other by their high bending stiffness. At the same time, they show certain anisotropy due to the structure. Therefore a typical testing method of structured semi-finished parts (single sheet metals, sandwiches)is the bending test. The literature review revealed that in many studies no special demands on tests of structured materials were made. This concerns particularly the structure arrangement, structure direction and structure location of the specimen relative to the mandrel position during bending tests, i. e., the direction of the fixed load relative to the structure. The aim of this study was to determine the influence of the test specification on flexural behavior. In the present paper, honeycomb-structured sheet metals were examined using 3-point bending tests. Bending stiffness and lightweight potential were calculated with respect to the location of load application and compared for different structure arrangements,directions and locations. The influence of the anisotropy on flexural behavior of the honeycomb-patterned sheet metals was moderate.}, language = {en} } @inproceedings{HaaseReinholdWolletal., author = {Haase, Florian Vincent and Reinhold, Maximilian and Woll, Ralf and Wolf, Matthias and Seidlitz, Holger}, title = {Reliability capability assessment of cooperative networks using the example of developing demonstrators of structured materials}, series = {Risk, Reliability and Safety: Innovating Theory and Practice, Proceedings of the ESREL 2016, Glasgow (United Kingdom)}, booktitle = {Risk, Reliability and Safety: Innovating Theory and Practice, Proceedings of the ESREL 2016, Glasgow (United Kingdom)}, editor = {Walls, Lesley and Revie, Matthew and Bedford, Tim}, publisher = {CRC Press}, address = {Boca Raton}, isbn = {978-1-138-02997-2}, pages = {1323 -- 1329}, language = {en} } @misc{ZhangMelcherTravitzkyetal., author = {Zhang, Wei and Melcher, Reinhold and Travitzky, Nahum and Greil, Peter}, title = {Three-Dimensional Printing of Complex-Shaped Alumina/Glas Composites}, series = {Advanced engineering materials}, volume = {11}, journal = {Advanced engineering materials}, number = {12}, issn = {1527-2648}, doi = {10.1002/adem.200900213}, pages = {1039 -- 1043}, language = {en} } @inproceedings{CyprisWeclasGreiletal., author = {Cypris, Jochen and Weclas, Miroslaw and Greil, Peter and Schlier, Lorenz M. and Travitzky, Nahum and Zhang, Wei}, title = {Application of macro-cellular SiC reactor to diesel engine-like injection and combustion conditions}, series = {Porous Media and its Applications in Science, Engineering, and Industry: Fourth International Conference, Potsdam, Germany, 17-22 June 2012}, booktitle = {Porous Media and its Applications in Science, Engineering, and Industry: Fourth International Conference, Potsdam, Germany, 17-22 June 2012}, publisher = {AIP, American Inst. of Physics}, address = {Melville, NY}, isbn = {978-0-7354-1053-4}, doi = {10.1063/1.4711197}, pages = {341 -- 346}, language = {en} } @misc{SchlierZhangTravitzkyetal., author = {Schlier, Lorenz M. and Zhang, Wei and Travitzky, Nahum and Greil, Peter and Cypris, Jochen and Weclas, Miroslaw}, title = {Macro-Cellular Silicon carbide Reactors for Nonstationary Combustion Under Piston Engine-Like Conditions}, series = {International Journal of Applied Ceramic Technology}, volume = {8}, journal = {International Journal of Applied Ceramic Technology}, number = {5}, issn = {1744-7402}, doi = {10.1111/j.1744-7402.2010.02591.x}, pages = {1237 -- 1245}, language = {en} } @misc{ZhangTravitzkyHuetal., author = {Zhang, Wei and Travitzky, Nahum and Hu, Chunfeng and Zhou, Yanchun and Greil, Peter}, title = {Reactive Hot Pressing and Properties of Nb2AlC}, series = {Journal of the American Ceramic Society}, volume = {92}, journal = {Journal of the American Ceramic Society}, number = {10}, issn = {1551-2916}, doi = {10.1111/j.1551-2916.2009.03187.x}, pages = {2396 -- 2399}, language = {en} } @misc{ZhangTravitzkyGreil, author = {Zhang, Wei and Travitzky, Nahum and Greil, Peter}, title = {Formation of NbAl3/Al2O3 Composites by pressureless reactive Infiltration}, series = {Journal of the American Ceramic Society}, volume = {91}, journal = {Journal of the American Ceramic Society}, number = {9}, issn = {1551-2916}, doi = {10.1111/j.1551-2916.2008.02583.x}, pages = {3117 -- 3120}, language = {en} } @misc{MelcherZhangTravitzkyetal., author = {Melcher, Reinhold and Zhang, Wei and Travitzky, Nahum and Greil, Peter}, title = {3D-Printing of Al2O3/Cu-O Composites}, series = {Ceramic Forum international}, volume = {83}, journal = {Ceramic Forum international}, number = {13}, issn = {0173-9913}, pages = {18 -- 22}, language = {en} } @misc{JakobsenZhangDoynovetal., author = {Jakobsen, Daniel and Zhang, Wei and Doynov, Nikolay and B{\"o}hm, Anna and Malzbender, J{\"u}rgen and Michailov, Vesselin and Roosen, Andreas}, title = {Thermal shock behaviour of laminated multilayer refractories for steel casting applications reinforced by residual stresses}, series = {Ceramics International}, volume = {42}, journal = {Ceramics International}, number = {12}, issn = {0272-8842}, doi = {10.1016/j.ceramint.2016.05.149}, pages = {13562 -- 13571}, language = {en} } @misc{ZhangDoynovOssenbrinketal., author = {Zhang, Wei and Doynov, Nikolay and Ossenbrink, Ralf and Michailov, Vesselin}, title = {Physical and FE-Simulation of Thermal Shock Behaviour of Refractory Ceramics}, series = {refractories WORLDFORUM}, volume = {8}, journal = {refractories WORLDFORUM}, number = {2}, issn = {1868-2405}, pages = {110 -- 117}, language = {en} } @inproceedings{ZhangPrieferOleninaetal., author = {Zhang, Wei and Priefer, Marian and Olenina, Mariia and Ossenbrink, Ralf and Michailov, Vesselin}, title = {Additive manufacturing by laser beam build-up welding}, series = {6th International Conference on Additive Technologies - iCAT 2016, N{\"u}rnberg, Germany, 29. - 30. November 2016}, booktitle = {6th International Conference on Additive Technologies - iCAT 2016, N{\"u}rnberg, Germany, 29. - 30. November 2016}, isbn = {978-961-285-537-6}, pages = {324 -- 327}, language = {en} } @inproceedings{ZhangSchrammKaneneksetal., author = {Zhang, Wei and Schramm, Maximilian and Kaneneks, Michael and Michailov, Vesselin and Fleischhauer, Matthias}, title = {Laserstrahl-Auftragschweißen mit pulverf{\"o}rmigen keramischen und metallischen Zusatzwerkstoffen zur Herstellung von Gradientenwerkstoffen}, series = {Große Schweißtechnische Tagung, N{\"u}rnberg, 15. - 17. September 2015}, booktitle = {Große Schweißtechnische Tagung, N{\"u}rnberg, 15. - 17. September 2015}, publisher = {DVS Media}, address = {D{\"u}sseldorf}, isbn = {978-3-945023-46-4}, pages = {842 -- 845}, language = {de} } @inproceedings{ZhangDoynovOssenbrinketal., author = {Zhang, Wei and Doynov, Nikolay and Ossenbrink, Ralf and Michailov, Vesselin and Scheithauer, Uwe and Michaelis, Alexander}, title = {Investigation of thermal shock behaviour of refractory ceramics based on the calcium-aluminate}, series = {14th Biennial Worldwide Congress Unified International Technical Conference on Refractories (UNITECR) 2015, Vienna, Austria, September 15-18, 2015}, booktitle = {14th Biennial Worldwide Congress Unified International Technical Conference on Refractories (UNITECR) 2015, Vienna, Austria, September 15-18, 2015}, address = {Hannover}, isbn = {978-3-9815813-1-7}, language = {en} } @misc{AtangaZhangDreibatietal., author = {Atanga, Valetine Kubong and Zhang, Wei and Dreibati, Ossama and Doynov, Nikolay and Ossenbrink, Ralf and Michailov, Vesselin and Scheffler, Michael}, title = {Alumina-mullite Materials for Refractory Applications: Microstructure, Physical and Finite Element Simulation of Thermal Shock Behaviour}, series = {refractories WORLDFORUM}, volume = {4}, journal = {refractories WORLDFORUM}, number = {1}, issn = {1868-2405}, pages = {159 -- 164}, language = {en} } @misc{HantelmannFritzscheMichailovetal., author = {Hantelmann, Cord and Fritzsche, Sebastian and Michailov, Vesselin and Boywitt, Ralf and Risse, Steffen and Paulinus, Dietmar}, title = {Utilisation of aluminium foam sandwich components in welded structures}, series = {Welding and Cutting}, journal = {Welding and Cutting}, number = {5}, issn = {1612-3433}, pages = {317 -- 325}, language = {en} } @misc{HantelmannFritzscheMichailovetal., author = {Hantelmann, Cord and Fritzsche, Sebastian and Michailov, Vesselin and Boywitt, Ralf and Risse, Steffen and Paulinus, Dietmar}, title = {Einsatz von Aluminiumschaum-Sandwich-Bauteilen in Schweißkonstruktionen}, series = {Schweissen und Scheiden}, volume = {68}, journal = {Schweissen und Scheiden}, number = {3}, issn = {0036-7184}, pages = {106 -- 114}, language = {de} } @misc{GenchevDoynovOssenbrinketal., author = {Genchev, Gancho Vladimirov and Doynov, Nikolay and Ossenbrink, Ralf and Michailov, Vesselin}, title = {Modelling the Local Microstructure Properties due to Multi-Pass Welding}, series = {Materials Science Forum}, volume = {Vol. 879}, journal = {Materials Science Forum}, issn = {0255-5476}, doi = {10.4028/www.scientific.net/MSF.879.595}, pages = {595 -- 600}, language = {en} }