Modélisation du dimensionnement en fatigue des mécanismes à grand nombre de cycles.

Abstract

Knowing the causes of material damage is a top priority for design engineers to avoid sudden breakage of equipment in service. One of the most important reasons for material failure is fatigue this phenomenon can be defined as damage to the metal under repeated stress and below the yield stress. The main objective of this study has been the modeling and the design during fatigue of a car part, among others the suspension arm. A Manson-Coffin strain approach was chosen and applied for three selected aluminum alloys, the numerical simulation was carried out in the fatigue module ""AnsysNcode design life"" to predict the fatigue behavior of the three materials which allowed deciding on the material that offers a better resistance to fatigue. Another objective was targeted that is the application of the multiaxial fatigue criteria chosen for the structure design, the aim was to estimate the danger coefficient associated with each criterion. Their mathematical models have been integrated into a FORTRAN program. The numerical simulation has been realized in ABAQUS to estimate the field of the constraints reigning in the structure.