Analysis of fretting fatigue initial crack path in Al7075-T651 using cylindrical contact. (April 2017) - Vázquez, J.
Abstract: This paper analyses the initial crack path in a fretting fatigue test of Al7075-T651 alloy with a cylindrical contact and compares the capability of some multiaxial fatigue criteria to predict the crack initiation path. The experimental crack initiation paths obtained in the tests are optically measured along the fracture surface using a focus variation technique. The Fatemi-Socie (FS) and Smith-Watson-Topper (SWT) multiaxial fatigue parameters obtained from an analytical model, allow us to determine the controlling parameters of the crack initiation process observed in the tests and to estimate the crack path during the early stage of the crack growth. Highlights: Fretting cracks initiate perpendicular to the surface and later rotate a small angle to growth beneath the contact. Initial cracks are nearly semi-elliptical and similar to those produced with spherical contact The average critical plane fatigue parameters along a certain length gives better results their values at a material point.In these cases the SWT parameter gives better estimations than the FS one. In these cases the SWT parameter gives better estimations than the FS one.