@phdthesis{42758, author = {{Gerkens, Michael}}, isbn = {{978-3-8440-7583-0}}, title = {{{Entwicklung einer Methodik zur numerischen Simulation des Hochgeschwindigkeits-Bolzensetzens}}}, year = {{2020}}, } @phdthesis{42795, author = {{Große Daldrup, Anna }}, title = {{{Modellierung des Strömungs- und Trennverhaltens viskoser Gemische in Packungskolonnen basierend auf tomographischen Untersuchungen}}}, year = {{2020}}, } @article{43160, abstract = {{Refill friction stir spot welding (RFSSW) is a highly flexible and promising solid-state joining method for aluminium alloys. Alternatively, resistance spot welding (RSW) can be stated as an appropriate joining method which can be automated and used within a high-volume production due to short process times. Both processes do not need any additional elements and a flat surface on both sides of the joints can be realised. In order to meet the modern requirements for crash safety and structural stiffness, thermal and mechanical joining methods are mainly combined by using single-component epoxy resin adhesives. Due to an insufficient knowledge about the application of both thermal joining methods for the abovementioned material combinations combined with additional adhesives, deeper investigations were done regarding the interactions of the polymers and the joining processes. Starting with a brief presentation of the boundary conditions of the investigations and the refill friction stir spot welding and resistance spot welding of high-strength aluminium alloys with sheet thicknesses bigger than 5.8 mm, the paper introduces the process-related joint properties of friction-based and resistance-based welded joints. Afterwards, the paper discusses the influences of the process parameter on the metallographic joint formation and load-bearing capacities for a selected two-sheet and four-sheet material combination. When combining the spot welding technologies with adhesives, the process parameters of the RFSSW process have to be adapted for the two-sheet combination by adding a squeeze-out step, while for RSW, just the preholding time has to be increased. Different challenges for both joining methods are shown. For RFSSW, the gap formation has to be considered when welding big total sheet thicknesses, while for RSW, the shape of the weld nugget is more important for an appropriate joint performance. Additionally, process optimisations for less adhesive incineration will be discussed for both joining processes, and the influences of the adhesive on the joint formation will be addressed with the help of load-bearing capacity evaluations. The paper closes with specific recommendations for the realisation of refill friction stir and resistance spot-welded joints with and without adhesive in the field of Al joints with big total sheet thicknesses which meet the quality demands and an outlook for further research steps will be given.}}, author = {{Schmal, Christopher and Meschut, Gerson}}, issn = {{0043-2288}}, journal = {{Welding in the World}}, keywords = {{Metals and Alloys, Mechanical Engineering, Mechanics of Materials}}, number = {{9}}, pages = {{1471--1480}}, publisher = {{Springer Science and Business Media LLC}}, title = {{{Refill friction stir spot and resistance spot welding of aluminium joints with large total sheet thicknesses (III-1965-19)}}}, doi = {{10.1007/s40194-020-00922-2}}, volume = {{64}}, year = {{2020}}, } @article{43162, abstract = {{Monitoring systems for machines, plants, materials and equipment are increasingly used in production processes. These online condition monitoring systems can detect damage or excessive loads at an early stage and can drastically reduce or prevent long downtimes of plants and machines as well as high repair and maintenance costs. This paper depicts a method for online crack detection with pattern recognition methods for specimens joined by self-pierce riveting under cyclic load in fatigue tests (laboratory application). A software specially conceived for this application was developed. This software, AnrissMF, uses active acoustic testing with a structure-borne sensor to detect cracks in the joints at a very early stage. It is shown in this paper that this software can detect cracks much earlier than classical failure criteria for joints (i. e. before any drop in stiffness or frequency is observed). Furthermore, the successful application of software AnrissMF for online crack detection during the fatigue strength test is presented.}}, author = {{Gollnick, Maik and Giese, Patrick and Hein, David and Meschut, Gerson and Herfert, Daniel}}, issn = {{2195-8572}}, journal = {{Materials Testing}}, keywords = {{Mechanical Engineering, Mechanics of Materials, General Materials Science}}, number = {{9}}, pages = {{877--882}}, publisher = {{Walter de Gruyter GmbH}}, title = {{{Early stage crack detection in mechanically joined steel/aluminum joints by condition monitoring}}}, doi = {{10.3139/120.111558}}, volume = {{62}}, year = {{2020}}, } @article{43161, author = {{Schmal, Christopher and Meschut, Gerson}}, issn = {{0043-2288}}, journal = {{Welding in the World}}, keywords = {{Metals and Alloys, Mechanical Engineering, Mechanics of Materials}}, number = {{3}}, pages = {{437--448}}, publisher = {{Springer Science and Business Media LLC}}, title = {{{Process characteristics and influences of production-related disturbances in resistance element welding of hybrid materials with steel cover sheets and polymer core}}}, doi = {{10.1007/s40194-019-00842-w}}, volume = {{64}}, year = {{2020}}, } @inbook{43181, abstract = {{„Digitalisierung“ und die oft analog benutzten Begriffe „Industrie 4.0“, „Arbeit 4.0“ usw., gelten als zentrale, aktuelle Entwicklungen in Deutschland. Gemeint ist damit der Einzug moderner Informations- und Kommunikationstechnologien, insbesondere des Computers, des Internets, von funkbasierten Überwachungssystemen, Steuerungs- und Netzwerktechnologien, z.B. RFID und Bluetooth, von mobilen Technologien bzw. Endgeräten usw., in die Berufs- und Arbeitswelt, in Dienstleistung und Produktion. Begleitet wird dies durch eine zunehmende Miniaturisierung von Technologien, die Ausstattung von Gegenständen mit einer eigenen Intelligenz (smart products) und die Vernetzung dieser Gegenstände zu cyber-physischen Systemen (CPS). Der Beitrag befasst sich mit der Frage, welche Potenziale, aber auch welche Risiken der digitale Wandel sowie die Digitalisierung von Aus- und Weiterbildung für Menschen birgt, die am Arbeitsmarkt als Geringqualifizierte, als Un- und Angelernte gelten. Es wird davon ausgegangen, dass gerade diese Menschen vom digitalen Wandel in besonderem Maße betroffen sein werden. Es ist zu erwarten, dass es durch den digitalen Wandel zu neuen Segmentierungen, zu neuen Ausschluss- und Benachteiligungsmechanismen kommt, von denen Geringqualifizierte und auch andere marginalisierte und benachteiligte Menschen am Arbeitsmarkt und in der beruflichen Bildung betroffen sein werden. Der Aus- und Weiterbildung wird eine besondere Bedeutung beigemessen, um diesen Menschen die Teilhabe und Mitgestaltung des digitalen Wandels zu ermöglich.}}, author = {{Heisler, Dietmar}}, booktitle = {{Digitalisierung über berufliche Bildung gestalten.}}, editor = {{Buchmann, Ulrike and Cleef, Maria}}, isbn = {{978-3-7639-6197-9}}, keywords = {{Digitalisierung, Geringqualifizierte, Weiterbildung, Un- und Angelernte}}, pages = {{29 -- 46}}, publisher = {{wbv}}, title = {{{Digitalisierung der Berufs- und Arbeitswelt. Herausforderungen und Potenziale in der Aus- und Weiterbildung für Geringqualifizierte, Un- und Angelernte}}}, year = {{2020}}, } @inproceedings{20680, author = {{Kappe, Fabian and Wituschek, Simon and Lechner, Michael and Bobbert, Mathias and Meschut, Gerson and Merklein, Marion}}, location = {{Darmstadt }}, title = {{{Investigation of influencing parameters on the joint formation of the self-piercing riveting process}}}, year = {{2020}}, } @inbook{24479, author = {{Moritzer, Elmar and Hüttner, M. and Henning, Bernd and Webersen, Manuel}}, booktitle = {{Advances in Polymer Processing 2020}}, title = {{{The Influence of Hydrothermal Aging on the Material Properties of Continuous Fiber-Reinforced Thermoplastics and its Non-Destructive Characterization}}}, doi = {{10.1007/978-3-662-60809-8_16}}, year = {{2020}}, } @article{22266, author = {{Grabo, Matti and Staggenborg, Christoph and Philippi, Kai Alexander and Kenig, Eugeny}}, issn = {{2296-598X}}, journal = {{Frontiers in Energy Research}}, title = {{{Modeling and Optimization of Rectangular Latent Heat Storage Elements in an Air-Guided Heat Storage System}}}, doi = {{10.3389/fenrg.2020.571787}}, volume = {{8}}, year = {{2020}}, } @article{21514, abstract = {{The influence of latent heat storage elements on the cooling performance and the temperature rise time of household refrigerating appliances is studied experimentally in the context of the “new global refriger- ator standard”IEC 62552:2015. In addition to the daily energy consumption, this international standard- ization introduced performance tests for cooling capacity and temperature rise time. While the cooling capacity has long been anchored in various test procedures of consumer organizations, the temperature rise time, which has only been tested on freezers so far, will be a decisive factor in the future. Moreover, the need for so-called "smart appliances" that may balance power consumption is increasing since such devices may compensate the volatility of renewable energies and thus stabilize the power grid. Against this background, eight commercial household refrigerators and refrigerator-freezers are equipped with polymer-bound phase change materials (PCM) and their performance is determined under the new stan- dard test conditions. The results show that the introduction of PCM increases the cooling capacity by up to 33 % and also increases the temperature rise time by up to 145 %, without affecting power consump- tion, as compared to the unmodified refrigeration appliances.}}, author = {{Sonnenrein, Gerrit and Baumhögger, Elmar and Elsner, Andreas and Morbach, A. and Neukötter, Moritz and Paul, Andreas and Vrabec, J.}}, issn = {{0140-7007}}, journal = {{International Journal of Refrigeration}}, pages = {{448--456}}, publisher = {{Elsevier}}, title = {{{Improving the performance of household refrigerating appliances through the integration of phase change materials in the context of the new global refrigerator standard IEC 62552:2015}}}, doi = {{10.1016/j.ijrefrig.2020.07.025}}, volume = {{119}}, year = {{2020}}, } @article{21512, abstract = {{Despite the omnipresence of household refrigeration appliances, there is still a lack of knowledge about their agerelated efficiency loss over time. Past studies provide basic evidence for increasing electricity consumption of cooling appliances with ageing but fail to investigate the associated technical wear. Concentrating on the degradation of the thermal insulation, we first determined the ageing process of sealed samples of polyurethane rigid foam by investigating changes in cell gas composition and thermal conductivity over time. Simultaneously, the main challenge was to develop an approach that investigates the age-related efficiency loss of the insulation without its destruction. This testing procedure is referred to as the Bonn method. The non-destructive Bonn method was applied to varying refrigerator models in a series of successive experiments to evaluate the insulation degradation over time. Subsequently, the physical relationship between the test value of the Bonn method and the heat transfer through the multi-layered compartment walls of domestic refrigeration appliances was established, ultimately characterising the degrading insulation in terms of increasing heat transfer. Our results give substantiated evidence that the efficiency loss of cooling appliances is greatly influenced by insulation degradation over time. The ageing of sealed samples of polyurethane rigid foam indicates a large initial increase of thermal conductivity by 15% within the first year, corresponding to a change in cell gas composition. These results are in line with those of the Bonn method, emphasising an increasing heat flow through the multi-layered compartment walls of domestic refrigerators with ageing. Therewith, the present study is of significance to a wide range of stakeholders and forms the basis for future research.}}, author = {{Hueppe, Christian and Geppert, Jasmin and Stamminger, Rainer and Wagner, Hendrik and Hoelscher, Heike and Vrabec, Jadran and Paul, Andreas and Elsner, Andreas and Becker, Wolfgang and Gries, Ulrich and Freiberger, Alfred}}, issn = {{1359-4311}}, journal = {{Applied Thermal Engineering}}, publisher = {{Elsevier}}, title = {{{Age-related efficiency loss of household refrigeration appliances: Development of an approach to measure the degradation of insulation properties}}}, doi = {{10.1016/j.applthermaleng.2020.115113}}, volume = {{173}}, year = {{2020}}, } @article{15945, author = {{Tinkloh, Steffen Rainer and Wu, Tao and Tröster, Thomas and Niendorf, Thomas}}, issn = {{0263-8223}}, journal = {{Composite Structures}}, title = {{{A micromechanical-based finite element simulation of process-induced residual stresses in metal-CFRP-hybrid structures}}}, doi = {{10.1016/j.compstruct.2020.111926}}, volume = {{238}}, year = {{2020}}, } @inproceedings{23409, author = {{Bertling, René and Hack, Mathias and Ausner, Ilja and Kenig, Eugeny}}, title = {{{CFD Simulation of Film and Rivulet Flows on Microstructured Surfaces}}}, year = {{2020}}, } @inproceedings{22965, author = {{Rozo Vasquez, Julian and Arian, Bahman and Riepold, Markus and Homberg, Werner and Trächtler, Ansgar and Walther, Frank}}, booktitle = {{ 54. Metallographie-Tagung}}, pages = {{75--81}}, title = {{{Microstructural investigation on phase transformation during flow forming of the metastable austenite AISI 304 }}}, year = {{2020}}, } @article{44371, author = {{Ahrens, Stephan}}, journal = {{Journal of Italian Cinema & Media Studies 9, Nr. 1}}, number = {{Nr. 1}}, pages = {{105--115}}, title = {{{Federico Fellini’s Sanctifying Effect. }}}, year = {{2020}}, } @article{22898, author = {{Schultz, Andreas Maximilian and Lamers, Christoph and Koch, Rainer and Lüke, Richard and Sauerland, Torben}}, journal = {{vfdb-Zeitschrift}}, title = {{{IRiS – Intelligente Rettung im SmartHome}}}, volume = {{4}}, year = {{2020}}, } @inproceedings{42892, abstract = {{This paper presents the results of static short-term and long-term tensile tests for beta-nucleated joined polypropylene samples by the hot plate welding process. In the present study different dimensionless joining displacements are accounted for. The results show that high short-term tensile strength does not directly transfer to high long-term tensile strength. The morphology of the weld seam in the joined samples is examined by means of transmitted and reflected light microscopy. For the dimensionless joining displacements of 0.75 and 0.95, stretched spherulites are obtained. X-Ray diffraction can be used as a tool for qualitative and quantitative analysis and eventually for differentiation of samples of various joining displacements.}}, author = {{Wübbeke, Andrea and Schöppner, Volker and Paul, André and Tiemann, Michael and Austermeier, Laura and Fitze, Marcus and Chen, Mingie and Jakob, Fabian and Heim, Hans-Peter and Wu, Tao and Niendorf, Thomas and Röhricht, Marie-Luise and Schmidt, Michael}}, booktitle = {{SPE ANTEC 2020: The Virtual Edition 5 }}, title = {{{Long- and Short-Term Tensile Strength and Morphology of Joined Beta-Nucleated Polypropylene Parts}}}, year = {{2020}}, } @inproceedings{24245, author = {{Schöppner, Volker and Wübbeke, Andrea and Geißler, B. and Schmidt, M. and Maginer, A. and Wu, T. and Niendorf, T. and Jakob, F. and Heim, H.}}, booktitle = {{73rd Annual Assembly of the International Institute of Welding (IIW)}}, location = {{Marina Bay (Singapore)}}, publisher = {{Springer-Verlag}}, title = {{{Investigation of residual stresses of hot plate welding}}}, year = {{2020}}, } @article{24236, abstract = {{In diesem Artikel werden das Scherzugverhalten und der morphologische Zustand von konturgeschweißtem Polypropylen (PP) mit einem Massenanteil von 0,2% Ruß untersucht. Dabei zeigen die Ergebnisse ...}}, author = {{Schöppner, Volker and Wübbeke, Andrea and Schriegel, Fabian and Paul, Andrej and Tiemann, Michael and Geißler, Bastian and Schmidt, Michael and Magnier, Arnaud and Niendorf, Thomas }}, journal = {{Joining Plastics}}, pages = {{30--35}}, title = {{{Selected Aspects for the Assessment of Laser Transmission Welding}}}, year = {{2020}}, } @inproceedings{24472, author = {{Schöppner, Volker and Wübbeke, Andrea and Paul, A. and Tiemann, M. and Austermeier, Laura and Fitze, M. and Chen, M. and Jakob, F. and Heim, H.-P- and Wu, T. and Niendorf, T. and Röhricht, M.-L. and Schmidt, M.}}, booktitle = {{ANTEC20}}, location = {{Texas (USA)}}, title = {{{LONG- AND SHORT-TERM TENSILE STRENGTH AND MORPHOLOGY OF JOINED BETA-NUCLEATED POLYPROPYLENE PARTS}}}, year = {{2020}}, }