The objective of this study is to evaluate the potential of light alloy use in automobile parts by studying their fatigue life using various parameters such as the effect of the suspension, the nature of the excitation, the
geometry and the weight of the part. The part under study is the lower suspension arm made of 7075-T6 aluminium alloy. The energy approach enables us to compare two of the same order of tensors, the multiaxial and
the uniaxial cases. In both cases, the strain energy density is a zero tensor order. The random displacement excitation is obtained analytically from the power spectral density PSD. The force excitation is obtained by a simple normalisation of spectrum displacement. To avoid the use of the Newton-Raphson method, during the partial fatigue life calculation step in all the elements of the mesh, we create a Matlab interface to identify the critical elements. The strain energy SENER signal of the critical element is corrected to remove the anomalies by a WAFO Matlab interface algorithm. Rainflow cycles are extracted using the Markov formulation in order to calculate the number of signal repetitions to failure, wich is calculated from the Miner law. The results show that the studied loading signal must be repeated 8.86*1011 times before a 25 mm thick aluminium 7075-T6 alloy part


Fatigue; aluminium; automotive; suspension; optimisation; failure

Texte intégral :



A Bignonnet "Approche globale d’allégement des véhicules "

Mec. Ind. (2001) 2, pp 173-180.

W. S. Miller, L. Zhuang, J. Bottema, A. J. Wittebrood, P. De

Smet, A. Haszler and A. Vieregge "Recent development in aluminium alloys for the automotive industry" Materials Science and Engineering, A280 (2000), pp 37-49.

Masaaki Saito, Shuuichiro Iwatsuki, Kunihiro Yasunaga and

Kimitaka Andoh "Development of aluminium body for the most fuel efficient vehicle" JSAE Review 21 (2000) pp 511-516.

K. Wilfred, P. M. Jean and Z. Gérald "Introduction à la science

des matériaux" Presse Polytechniques et Universitaires Romandes, second edition, 404 pages, 1991.

André Bazergui, Thang Bui-Quo, André Biron, Georges McIntyre and Charles Laberge,"Résistance des matériaux"

second edition, École Polytechnique de Montréal, 1993, 595


S. Cervello, G. Donzella and A. Pola "Analysis and design of a

low-noise railway wheel" Proceedings of the Institution of

mechanical Engineers. Part F, Journal of Rail, Vol 215, 2001, pp 79-92.

A. Elmarakbi, H. El-hage and S. Bhattacharjee "Multiaxial

fatigue crack initiation by strain energy density using finite

element method" CSME Forum 2002, Kingston, may 21-24.

W. V. Mars "Cracking energy density as a predictor of fatigue

life under multiaxial conditions" Rubber Chemistry and Technology, Akron, Mar/Apr 2002, pp 1-17.

A. de-Andrés, J.L.Pérez and M. Ortiz, "Elastoplastic finite

element analysis of three-dimensional fatigue crack growth in

aluminium shafts subjected to axial loading" International

Journal of Solids and Structures, 36 (1999), pp 2231-2258.

H. Rahnejat "Multi-Body-Dynamics : vehicles, machines and

mechanisms" Society of Automotive Engineers, Inc., 1998, 355 pages.

M. Bouazara "Étude et analyse de la suspension active et

semi-active des véhicules routiers" Ph.D. thesis, Laval university, 197p. 1997.

M. Gbadebo Owolabi, Meera and N. K. Sing "A comparison

between analytical models that approximate notch-root elastic-plastic strain-stress components in two-phase, particule-reinforced, metal matrix composites under multiaxial cyclic loading: Theory" International Journal of Fatigue, 28, (2006) pp 910-917.

M. Gbadebo Owolabi, Meera and N.K. Sing "A comparison

between analytical models that approximate notch-root elastic-plastic strain-stress components in two-phase, particule-reinforced, metal matrix composites under multiaxial cyclic loading: experiments" International Journal of Fatigue, 28, (2006) pp 918-925.

J. S Sun, K. H Lee. and H. P. Lee "Comparison of implicit

and explicit finite element methods for dynamic problems"

Journal of Materials Processing Technology 105 (2000) pp


N. Rebelo, J. C. Nagategaal and Taylor L. M. "Comparison of

implicit and explicit finite element methods in the simulation

forming processes" Numerical methods in industrial forming

processes: proceedings 4th international 1992 pp 99-108.

M. Haiba, D. C. Barton and P. C. Levesley "The development of an optimization algorithm based on fatigue life" International Journal of Fatigue 25 (2003) 299-310.


  • Il n'y a présentement aucun renvoi.

Direction des Publications et de l'animation scientifique

Université des Frères Mentouri Constantine 1. Route Ain El-Bey. 25000. Algérie.