A crack arrest methodology based on Bazant's parameter to estimate threshold fretting conditions

Department of Mechanical Engineering, University of Brasília, 70910-900, DF, Brazil

Abstract

Fracture mechanics-based methodologies, considering either the Kitagawa-Takahashi (K-T) or El Haddad threshold diagrams, have been used to estimate crack arrest under fretting conditions. It is claimed in this work that the success of these diagrams to correlate experimental data depends on material behaviour. Therefore, a more general methodology based on the Bazant's threshold diagram is proposed here. An appealing feature of such a diagram is that, depending on the value of an adjustable parameter, it may collapse into the K-T or El Haddad diagrams as limiting cases. A preliminary assessment of the model was carried out with available sizes of short arrested cracks observed in cylindrical contacts under partial slip regime. The best estimates were obtained when the upper limit of the Bazant's diagram (K-T diagram) was considered.