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Frequency FE-Based Weld Fatigue Life Prediction of Dynamic Systems
ISSN: 0148-7191, e-ISSN: 2688-3627
Published March 28, 2017 by SAE International in United States
This content contains downloadable datasetsAnnotation ability available
In most aspects of mechanical design related to a motor vehicle there are two ways to treat dynamic fatigue problems. These are the time domain and the frequency domain approaches. Time domain approaches are the most common and most widely used especially in the automotive industries and accordingly it is the method of choice for the fatigue calculation of welded structures. In previous papers the frequency approach has been successful applied showing a good correlation with the life and damage estimated using a time based approach; in this paper the same comparative process has been applied but now extended specifically to welded structures. Both the frequency domain approach and time domain approach are used for numerically predicting the fatigue life of the seam welds of a thin sheet powertrain installation bracketry of a commercial truck submitted to variable amplitude loading. Predicted results are then compared with bench tests results, and their accuracy are rated. Ultimately the key question addressed within this study is whether the frequency domain approach can be a better alternative when compared to the conventional time domain approaches, when used to determine weld fatigue durability. It is demonstrated that when the fatigue damage is efficiently evaluated using the frequency approach (PSDs), it permits a better understand of the importance of the dynamic characteristic of the actual system, isolating the mode contributions to the total damage, guiding how much a test can be accelerated or even how this damage can be minimized by changing the normal modes of this system.
CitationCosta, E., Bishop, N., and Cardoso, V., "Frequency FE-Based Weld Fatigue Life Prediction of Dynamic Systems," SAE Technical Paper 2017-01-0355, 2017, https://doi.org/10.4271/2017-01-0355.
Data Sets - Support Documents
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- Ferreira, W., Meehan, T., Cardoso, V., and Bishop, N., "A Comparative Study of Automotive System Fatigue Models Processed in the Time and Frequency Domain," SAE Technical Paper 2016-01-0377, 2016, doi:10.4271/2016-01-0377.
- Bishop, N., Murthy, P., Sweitzer, K., and Kerr, S., "Time vs Frequency Domain Analysis for Large Automotive Systems," SAE Technical Paper 2015-01-0535, 2015, doi:10.4271/2015-01-0535.
- Palmer, T. and Bishop, N., "Solver Embedded Fatigue," SAE Technical Paper 2014-01-0904, 2014, doi:10.4271/2014-01-0904.
- Bishop, N., Kerr, S., Murthy, P., and Sweitzer, K., "Advances Relating to Fatigue Calculations for Combined Random and Deterministic Loads," SAE Technical Paper 2014-01-0725, 2014, doi:10.4271/2014-01-0725.
- Fermér, M., Andréasson, M., and Frodin, B., "Fatigue Life Prediction of MAG-Welded Thin-Sheet Structures," SAE Technical Paper 982311, 1998, doi:10.4271/982311.
- eFatigue, “Welded Structures”, http://www.efatigue.com/welds/, accessed May, 2016.
- Costa, E., “FE-Based Weld Fatigue Life Prediction of Powertrain Installation Bracketry”, SAE Technical Paper 2016-36-0149, 2016, doi:10.4271/2016-36-0149.
- Radaj, D., Sonsino, C.M., Frickle, W., “Recent Developments in Local Concepts of Fatigue Assessment of Welded Joints”, International Journal of Fatigue, 2009, 31, 2-11.
- Wei, Z., Yang, F., Luo, L., Avery, K. et al., "Fatigue Life Assessment of Welded Structures with the Linear Traction Stress Analysis Approach," SAE Int. J. Mater. Manf. 5(1):183-194, 2012, doi:10.4271/2012-01-0524.
- Kang, H., Khosrovaneh, A., Amaya, M., Bonnen, J. et al., "Application of Fatigue Life Prediction Methods for GMAW Joints in Vehicle Structures and Frames," SAE Technical Paper 2011-01-0192, 2011, doi:10.4271/2011-01-0192.
- Wei, Z., Hamilton, J., Yang, F., Luo, L. et al., "Comparison of Verity and Volvo Methods for Fatigue Life Assessment of Welded Structures," SAE Technical Paper 2013-01-2357, 2013, doi:10.4271/2013-01-2357.
- HBM United Kingdom Limited, “DesignLife Theory Guide”, NCode 10.0, 2014.
- Bishop, N., Lack L., Li. T., Kerr, S. Analytical Fatigue Life Assessment of Vibration Induced Fatigue Damage. In: Proceedings of MSC World Users Conference. Universal City, California, USA. May 8-12, 1995.
- Bishop, N.W.M, Sherratt, F. Finite Element Based Fatigue Calculations. NAFEMS, 2000.
- Bishop, N, Sherratt, F. Fatigue life prediction from power spectral density data. Part 1, traditional approaches and Part 2, recent developments. Env. Eng., 2, (1989).
- CAEfatigue VIBRATION (CFV) User Guide & Verification Manual (Release 3.0). CAEfatigue Limited, UK, October 2016.