Microstructural-based analysis and modelling of the fatigue behaviour of cast Al-Si alloys
Analyse et modélisation du comportement en fatigue des alliages d'aluminium de fonderie
Communication avec acte
Abstract
This paper describes a microstructural-based high cycle fatigue behaviour model applied to cast Al-Si alloys used in an automobile context. These materials are characterized by the presence of different microstructural heterogeneities at different scales: the aluminium matrix (DAS/SDAS and the precipitation hardening level), inclusions (Si particles and intermetallic) and casting defects (porosity). It is shown that the effects of these factors on the HCF damage mechanisms are important and can depend on the loading mode. A multiaxial fatigue test campaign has been carried out using three cast aluminium alloys, fabricated by different casting processes (gravity die casting and lost foam casting), associated with several heat treatment(T7 and Hot Isostatic Pressing-HIP). The HIP treatment is used to eliminate or minimise the porosity. The first part of the article is dedicated to the experimental characterization of the HCF damage mechanisms. With regard to the effect of the casting defects, a study of natural fatigue crack growth and artificial long crack growth is presented and subsequently used to choose an appropriate fatigue strength criterion to take into account the effect of defects, for different loading modes (tension, torsion and combined tension-torsion). Finally, a flexible modelling framework, providing the possibility of combining any two suitable criteria, which leads to the construction of a multiaxial Kitagawa-Takahashi diagram, is used.
Files in this item
Related items
Showing items related by title, author, creator and subject.
-
Communication avec acteLE, Viet-Duc; BELLETT, Daniel; MOREL, Franck; SAINTIER, Nicolas; PALIN-LUC, Thierry; PESSARD, Etienne; OSMOND, Pierre (MATEC Web of Conferences, 2014)The aim of this work is to propose simple analytical tools to predict the fatigue strength of cast aluminium components as a function of the casting process and post-cast treatment. The proposed methodology is based on the ...
-
Article dans une revue avec comité de lectureThis article describes a microstructural-based high cycle fatigue strength modelling approach applied to different cast Al-Si alloys used in an automotive context. Thank to different casting processes (gravity die casting ...
-
Article dans une revue avec comité de lectureThis article is dedicated to the high cycle fatigue (HCF) behaviour of cast Al-Si alloys. In particular, three similar alloys with different microstructural characteristics are investigated. The result of an experimental ...
-
Article dans une revue avec comité de lecturePorosity generated by the casting process has a detrimental effect on the high cycle fatigue strength of cast aluminium alloys. The current study presents an investigation using the non-destructive X-ray micro-tomography ...
-
Article dans une revue avec comité de lectureEL KHOUKHI, Driss; MOREL, Franck; SAINTIER, Nicolas; BELLETT, Daniel; OSMOND, Pierre; LE, Viet Duc; ADRIEN, Jérôme (Elsevier, 2019)Cast Al-Si alloys have been widely used in automotive applications with regard to their low density and excellent thermal conductivity. Many components made of these alloys are subjected to cyclic loads which can lead to ...