Fatigue Stress Ratio Effect on Fretting-Fatigue Crack Nucleation: Comparison between Multi-Axial and Uni-Axial Predictions

Abstract:

This research focuses on high cycle fretting fatigue crack nucleation prediction. A plastic steel/steel cylinder/plane contact was investigated keeping constant the normal force and the maximum fatigue stress ratio but varying the fatigue stress ratio (R_F=0.6 to 1). The evolution of the crack length as function of the applied fretting tangential force amplitude at 10⁶ cycles allows us to formalize the crack nucleation condition. It shows that the threshold tangential force marking the crack nucleation (i.e. b_{p_th}=0μm) is not affected by the fatigue stress ratio. However an increase of the fatigue stress amplitude sharply increases the crack extension. To model the experiments, a 2D plastic plain strain FEM modeling is performed. As expected the computed stress field description is mesh dependent. However we demonstrate that a representative stress description is obtained at the 3^rd node (i.e. 2^nd node below the surface). By coupling this mesh condition and non-local critical distance approach, reliable prediction of the crack nucleation risk can be achieved either considering a Crossland multi-axial fatigue analysis or using a basic uni-axial Haighs description.

• Periodical: Advanced Materials Research (Volumes 891-892)
• Pages: 903-908
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.891-892.903
• Online since: March 2014
• Authors: Camille Gandiolle*, Siegfried Fouvry
• Keywords: Crack Nucleation, Fretting-Fatigue, Haigh Analysis, Stress Ratio Effect

References

[1] R.B. Waterhouse, Fretting Fatigue, Waterhouse, (1981).

[2] S. Fouvry, H. Gallien, B. Berthel, From uni- to multi-axial fretting-fatigue crack nucleation: Development of a stress-gradient-dependent critical distance approach, Int. J. Fatigue. (2013).

DOI: 10.1016/j.ijfatigue.2013.05.016

[3] S. Fouvry, F. Ruiz, P. Kapsa, L. Vincent, Stress and Fatigue analysis of fretting on a stressed specimen under partial slip condition, Tribotest J. 3 (1996) 1354–4063.

DOI: 10.1002/tt.3020030103

[4] R. Ferré, S. Fouvry, B. Berthel, J. -a. Ruiz-Sabariego, Stress gradient effect on the crack nucleation process of a Ti–6Al–4V titanium alloy under fretting loading: Comparison between non-local fatigue approaches, Int. J. Fatigue. 54 (2013) 56–67.

DOI: 10.1016/j.ijfatigue.2013.03.005

[5] S. Heredia, S. Fouvry, B. Berthel, E. Greco, Introduction of a principal stress-weight function, approach to predict the crack nucleation risk under fretting fatigue using FEM modeling, Submitt. to IJF. (n. d. ).

DOI: 10.1016/j.ijfatigue.2013.11.009

[6] J. Araújo, D. Nowell, The effect of rapidly varying contact stress fields on fretting fatigue, 24 (2002) 763–775.

DOI: 10.1016/s0142-1123(01)00191-8

[7] S. Fouvry, P. Kapsa, F. Sidoroff, L. Vincent, Identification of the characteristic length scale for fatigue cracking in fretting contacts, J Phys IV Fr. 8 (1998) 66.

DOI: 10.1051/jp4:1998820

[8] L. Susmel, D. Taylor, Can the conventional High-cycle multiaxial fatigue criteria be re-interpreted in terms of the theory of critical distances?, SDHM. 2 (2006) 91–108.

[9] J. Araújo, L. Susmel, D. Taylor, J.C.T. Ferro, J.L. a. Ferreira, On the prediction of high-cycle fretting fatigue strength: Theory of critical distances vs. hot-spot approach, Eng. Fract. Mech. 75 (2008) 1763–1778.

DOI: 10.1016/j.engfracmech.2007.03.026

[10] B. Crossland, Effect of large hydrostatic pressures on the torsional fatigue strength of an alloy steel, Proc. Int. Conf. Fatigue Met. (1956) 138–149.