PSI - Issue 19

Thorsten Voigt et al. / Procedia Structural Integrity 19 (2019) 4–11

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Dr.-Ing. Thorsten Voigt/ Structural Integrity Procedia 00 (2019) 000 – 000

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contribute to the efficient use of parking space in urban areas, its special feature is a strong focus on the lightweight construction of the supporting structure. The remarks in the paper focus on the lifetime evaluation of the rear axle of the vehicle. Here, component tests were carried out on the control arm of the axle and investigations on the subsystem of a half rear axle. The tests on the control arms were completed under uniaxial loading to simulate constant and variable amplitude lateral loads. Environmental conditions were simulated in some of the tests. For the tests on the half-axle module, a two-channel test setup was used, which can apply lateral and vertical loads to the assembly. The load spectra for the variable amplitude tests were derived from a scalable synthetic load program to simulate wheel loads. The paper outlines the application of the load program. The Gassner curves determined on the basis of these load signals are compared with the components Woehler curves and eval uated. Numerical and experimental stress analyses as well as the application of linear Palmgren-Miner damage accumulation serve to assess the test results for plausibility and to evaluate the service life. From the evaluation of the component tests, it can be concluded that the control arm is dimensioned sufficiently in relation to the requirements for lateral loading expected in the customer's application. According to the investigations, the influence of corro sion on the lifespan of the control arm is expressed by a factor of 1.45. In tests on the rear axle of the vehicle, premature failure of the control arm occurred because, due to the structural design of the assembly, the transmission of vertical forces is associated with high torsional moments in the control arm. Suggestions for changing the vertical load transmission were derived from the test results. These are implemented in the prototype of the vehicle, and allow for more robust features of the assembly in terms of durability. Acknowledgements The work presented in this contribution was co-funded by the European Union research project “Super Light Architectures for Safe and Affordable Urban Electric Vehicles ” , Grant Agree Number 605634, (ww.urban-ev.eu) within the Seventh Framework Programme. Eulitz, K.-G. & Kotte, K. L. (1999), Datensammlung Betriebsfestigkeit, Teil 1: Stahl- und Eisenwerkstoffe, Forschungskuratorium Maschinenbau, FKM, VDMA, Verband Deutscher Maschinen- und Anlagenbau. Grubisic, V. (1973), Bemessung und Prüfung von F ahrzeugrädern, Special Edition of „Automobiltechnische Zeitschrift“ , 75 (1), 9 – 18. Gudehus, H. & Zenner, H. (2004), Leitfaden für eine Betriebsfestigkeitsrechnung, 4th. Edition, Verlag Stahleisen GmbH, Düsseldorf. Köhler, M., Jenne, S., Pötter, K. & Zenner, H. (2012), Zählverfahren und Lastannahmen in der Betriebsfestigkeit, Springer Verlag Heidelberg Dordrecht London New York. Lipp, K., Schäfer, R. & Horwatitsch, D. (2017), Fatigue behaviour of aluminium tube crimp connections applying the electromagnetic pulse technology, in ‘Proceedings of the 7th International Conference on Fatigue Design, Fatigue Design 2017’, Sen lis, France. Müller, A., Grubisic, V., Fischer, G., Käumle, F., Schnell, R. & Hasenmaier, W. (1993), Simulation typisierter, mehraxialer Belastungsabläufe an Fahrzeug Achskomponenten, in Deutscher Verband für Materialforschung und -prüfung (DVM), „ Bauteillebensdauer: Rechnung und Versuch, 19. Vortragsveranstal tung des DVM Arbeitskreises Betriebsfestigkeit “ , 65 – 85. Schäfer, R. & Pasquale, P. (2009), Elektromagnetische Pulsumformtechnologie im industriellen E insatz’, published at companies homepage : http://pstproducts.com/infocenter.htm References