Stress Gradient Effect on the Cracking Process of a Ti-6Al-4V Titanium Alloy un-der Fretting Loading and Comparison of Non-local Predicted Nucleation Approaches
This study focuses on the stress gradient effect regarding the crack nucleation of a cylinder/plane Ti-6Al-4V titanium alloy contact under LCF fretting solicitations. Several local and non-local analytical approaches were compared to predict experimental results. The first part of the study presents fretting nucleation boundaries for three different cylinder radii on partial slip regime. In the next part,local and non-local approaches are tested. Local approach was compared to the square constant volume. In the last part,Grassland and Papadopoulos multiaxial fatigue criteria are computed and matched to each other.The methodology used sweeps a large range of stress gradients. The impact of the varying stress gradients shows that the larger the stress gradient the higher the crack nucleation threshold. Therefore a longer lifetime to crack nucleation should be observed for such configurations. A Crossland local form was used to demonstrate that a local stress state does not allow the prediction of a scale effect. A non-local approache based on simple geometries, the square surface approach was carried out and the results allowed the prediction of the empirical thresholds with a 3％ to 5％ margin error. The positive results obtained permitted to select a multi-axial fatigue criterion and a meaning volume which take into account the gradient effect of contact fretting behavior.
Fretting crack nucleation threshold multiaxial fatigue criterion stress gradient effeet non-local criterion
R. FERRé S. FOUVRY B. BERTHEL J-A. RUIZ-SABARIEGO
Laboratoire de Tribologie et Dynamique des Systèmes (LTDS),Ecole Centrale de Lyon,69134 Ecully cedex Laboratoire de Tribologie et Dynamique des Systèmes (LTDS),Ecole Centrale de Lyon,69134 Ecully cedex SNECMA Villaroche,SAFRAN group,77550 Moissy-Cramayel,France
国际会议
The 12th World Conference Titanium(第十二届世界钛会 Ti-2011)
北京
英文
1974-1978
2011-06-19（万方平台首次上网日期，不代表论文的发表时间）