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A voronoi FE fatigue damage model for life scatter in rolling contacts / Behrooz Jalalahmadi in Transactions of the ASME . Journal of tribology, Vol. 132 N° 2 (Avril 2010) 

Public ISBD [article]  in Transactions of the ASME . Journal of tribology > Vol. 132 N° 2 (Avril 2010) . - 14 p. Titre : A voronoi FE fatigue damage model for life scatter in rolling contacts Type de document : texte imprimé Auteurs : Behrooz Jalalahmadi, Auteur ; Farshid Sadeghi, Auteur Année de publication : 2011 Article en page(s) : 14 p. Note générale : Tribology Langues : Anglais (eng) Mots-clés : Ball  bearings  Crystal  microstructure  Elastic  moduli  Fatigue  Finite  element  analysis  Mechanical  contact  Microcracks  Normal  distribution  Rolling  bearings  Weibull  distribution Index. décimale : 621.5 Energie pneumatique. Machinerie et outils. Réfrigération Résumé : It has been widely accepted that the microstructure of bearing materials can significantly affect their rolling contact fatigue (RCF) lives. Hence, microlevel topological features of materials will be of significant importance to RCF investigation. In order to estimate the fatigue lives of bearing elements and account for the effects of topological randomness of the bearing materials, in this work, damage mechanics modeling approach is incorporated into a Voronoi finite element method recently developed by the authors. Contrary to most of the life models existing in the literature for estimating the RCF lives, the current model considers microcrack initiation, coalescence, and propagation stages. The proposed model relates the fatigue life to a damage parameter D, which is a measure of the gradual material degradation under cyclic loading. In this investigation, 40 semi-infinite domains with different microstructural distributions are subjected to a moving Hertzian pressure. Using the fatigue damage model developed, the initiation and total lives of the 40 domains are obtained. Also, the effects of initial material flaws and inhomogeneous material properties (in the form of normal distribution of the elastic modulus) on the fatigue lives are investigated. It is observed that the fatigue lives calculated and their Weibull slopes are in good agreement with previous experimental and analytical results. It is noted that introducing inhomogeneous material properties and initial flaws within the domains decreases the fatigue lives and increases their scatters. DEWEY : 621.5 ISSN : 0742-4787 En ligne : http://scitation.aip.org/getabs/servlet/GetabsServlet?prog=normal&id=JOTRE900013 [...] [article] A voronoi FE fatigue damage model for life scatter in rolling contacts [texte imprimé] / Behrooz Jalalahmadi, Auteur ; Farshid Sadeghi, Auteur . - 2011 . - 14 p. Tribology Langues : Anglais (eng) in Transactions of the ASME . Journal of tribology > Vol. 132 N° 2 (Avril 2010) . - 14 p. Mots-clés : Ball  bearings  Crystal  microstructure  Elastic  moduli  Fatigue  Finite  element  analysis  Mechanical  contact  Microcracks  Normal  distribution  Rolling  bearings  Weibull  distribution Index. décimale : 621.5 Energie pneumatique. Machinerie et outils. Réfrigération Résumé : It has been widely accepted that the microstructure of bearing materials can significantly affect their rolling contact fatigue (RCF) lives. Hence, microlevel topological features of materials will be of significant importance to RCF investigation. In order to estimate the fatigue lives of bearing elements and account for the effects of topological randomness of the bearing materials, in this work, damage mechanics modeling approach is incorporated into a Voronoi finite element method recently developed by the authors. Contrary to most of the life models existing in the literature for estimating the RCF lives, the current model considers microcrack initiation, coalescence, and propagation stages. The proposed model relates the fatigue life to a damage parameter D, which is a measure of the gradual material degradation under cyclic loading. In this investigation, 40 semi-infinite domains with different microstructural distributions are subjected to a moving Hertzian pressure. Using the fatigue damage model developed, the initiation and total lives of the 40 domains are obtained. Also, the effects of initial material flaws and inhomogeneous material properties (in the form of normal distribution of the elastic modulus) on the fatigue lives are investigated. It is observed that the fatigue lives calculated and their Weibull slopes are in good agreement with previous experimental and analytical results. It is noted that introducing inhomogeneous material properties and initial flaws within the domains decreases the fatigue lives and increases their scatters. DEWEY : 621.5 ISSN : 0742-4787 En ligne : http://scitation.aip.org/getabs/servlet/GetabsServlet?prog=normal&id=JOTRE900013 [...]