Issue 35

C. Gandiolle et alii, Frattura ed Integrità Strutturale, 35 (2016) 232-241; DOI: 10.3221/IGF-ESIS.35.27 241 C ONCLUSION he crack propagation rate of fretting fatigue loading was investigated both experimentally and numerically. The potential drop technique method was implemented on the fatigue fretting test device and a calibration curve was established. With this curve, the crack length was known throughout a fretting fatigue test. A decoupled approach was applied to estimate the stress intensity factor evolution with the fretting fatigue crack extension thus to predict the crack propagation risk. The contact stress state was obtained by finite elements modeling, then the mode I stress intensity factor was calculated using a weight function approach and finally the Paris law was applied on the deduced effective stress intensity range along the crack. It allowed for good estimation of the crack propagation rate. Finally these strategies were applied to a mixed load test, more representative of an industrial loading case. The predictive method was adjusted to consider the successive ΔK eff of each loading, depending on the number of cycles. This simple method allowed really good prediction of crack nucleation and crack arrest condition. The predicted crack extension was slightly too conservative; however it is consistent with the security coefficient needed in industry. Better predictions may be achieved using a more representative cyclic plastic law and more elaborate description of the ΔK eff parameter. R EFERENCES [1] Fouvry, S., Kapsa, P., Vincent, L., A multiaxial fatigue analysis of fretting contact taking into account the size effect, ASTM STP., 1367 (2000) 167-182. [2] Araújo, J., Nowell, D., The effect of rapidly varying contact stress fields on fretting fatigue, Int. J. Fatigue, 24 (2002) 763-775. [3] Araujo, J.A., Nowell, D., Analysis of pad size effects in fretting fatigue using short crack arrest methodologies, Int. J. Fatigue, 21 (1999) 947-956. [4] Ruiz, C., Boddington, P.H.B., Chen, K.C., An Investigation of Fatigue and Fretting in a Dovetail Joint, Exp. Mech., 24 (1984) 208-217. [5] Giannakopoulos, A.E., Lindley, T.C., Suresh, S., Aspects of equivalence between contact mechanics and fracture mechanics: theoretical connections and a life-prediction methodology for fretting-fatigue, Acta Mater., 46 (1998) 2955-2968. [6] Navarro, C., Munoz, S., Dominguez, J., On the use of multiaxial fatigue criteria for fretting fatigue life assessment, Int. J. Fatigue, 30 (2008) 32-44. [7] Gros, V., Etude de l’amorçage et de la propagation des fissures de fatigue dans les essieux-axes ferroviaires, Ecole centrale Paris, 1996. [8] Barnett, W., Troiono, A., Crack Propagation in Hydrogen Induced Brittle Fracture of Steel, J Met., 9 (1952) 94. [9] Kondo, Y., Sakae, C., Kubota, M., Yanagihara, K., Non-propagating crack behaviour at giga-cycle fretting fatigue limit, Fatigue Fract. Eng. Mater. Struct., 28 (2005) 501-506. [10] Meriaux, J., Fouvry, S., Kubiak, K.J., Deyber, S., Characterization of crack nucleation in TA6V under fretting-fatigue loading using the potential drop technique, Int. J. Fatigue, 32 (2010) 1658-1668. [11] Proudhon, H., Fouvry, S., Yantio, G.R., Determination and prediction of the fretting crack initiation: introduction of the (P, Q, N) representation and definition of a variable process volume, Int. J. Fatigue, 28 (2006) 707-713. [12] Gandiolle, C., Fouvry, S., Experimental Analysis and Modeling of the Crack Arrest Condition Under Severe Plastic Fretting Fatigue Conditions, Procedia Eng., 66 (2013) 783-792. [13] Bueckner, H.F., Weight functions and fundamental fields for the penny shaped and the half plane crack in three spaces, Int. J. Solids Struct., 23 (1987) 57-93. [14] Voisin, J.M., Vannes, A.B., Vincent, L., Daviot, J., Giraud, B., Analysis of a tube-grid oscillatory contact: methodology selection of superficial treatments, Wear, 181-183 (1995) 826-832. T