... Voronoi tessellations wherein each cell represents a material grain and the boundaries between them constitute the weak planes in the material. Fatigue cracks initiate on the weak planes where oscillating shear stresses are the strongest. Finite element analysis is performed to determine the magnitude...

... the experimental conclusions about the effect of an increasing tangential load on the crack initiation and propagation. 10 09 2010 08 04 2011 07 07 2011 07 07 2011 brittleness design of experiments discs (structures) fatigue cracks finite element analysis mechanical contact...

...Trevor S. Slack; Nihar Raje; Farshid Sadeghi; Gary Doll; Michael R. Hoeprich Inclusions are common in bearing materials and are a primary site for subsurface fatigue crack initiation in rolling element bearings. This paper presents a new approach for computing the pressure, film thickness...

... associated with the 0.2% strain amplitude was approximately 333 cycles to failure by building a model of high-stress/strain amplitudes and using the Coffin-Manson law. Thus, to prevent the thermal fatigue crack, we can increase the yielding strength and the fatigue resistance of the disk material...

...Nihar Raje; Farshid Sadeghi; Richard G. Rateick, Jr.; Michael R. Hoeprich Inclusions are the primary sites for subsurface fatigue crack initiation in bearing contacts. To understand the mechanisms of subsurface crack nucleation under contact loading, a detailed description of the stress field...

... the UMAT subroutine for ABAQUS , which was used in the finite element simulations. A empirical constant of the fatigue crack growth law A 1 constant in the tool wear formula E * reduced Young’s modulus in Hertz contact G contiguity of the WC grains...

... of the contact pressure, stress intensity factors, and maximum equivalent plastic strain. It is shown that a transition from tensile to shear dominant mode of fatigue crack growth occurs as the crack tip approaches the interface, resulting in further crack growth almost parallel to the layer interface...

.... , and Olsson , M. , 2000 , “ Initiation and Growth of Standing Contact Fatigue Cracks ,” Eng. Fract. Mech. , 65 , pp. 89 – 106 . Lin , X. B. , and Smith , R. A. , 1999 , “ Finite Element Modelling of Fatigue Crack Growth of Surface Cracked Plates, Part I: The Numerical Technique ,” Eng...

... failure (mechanical) mechanical contact internal stresses fatigue cracks finite element analysis The two distinct rolling contact failure modes are called subsurface and near surface as described by Lorosch 1 , Bastias et al. 2 , Tallian 3 , and many other researchers. The subsurface...

.... Contributed by the Tribology Division for publication in the ASME JOURNAL OF TRIBOLOGY . Manuscript received by the Tribology Division June 26, 2003; revised manuscript received January 14, 2004. Associate Editor: L. Chang. 26 June 2003 14 January 2004 28 06 2004 fatigue cracks...

...-dimensional interface element was developed to model the constitutive laws of the interface. The results demonstrated the capability of the model to predict the conditions under which small fretting-induced fatigue cracks are arrested. The model was validated by predicting the S-N curves produced...

... on the combination of the author’s RCF model, Hourlier and Pineau’s criterion for the branch prediction and experimental data and the corresponding models for fatigue crack extension that are derived from a Joint European project. Parametric studies on the influence of (i) residual stresses, (ii) both interfacial...

... Surface and Subsurface Origins ,” ASME J. Basic Eng. , 88 , pp. 624 – 636 . Miller , G. R. , Keer , L. M. , and Cheng , H. S. , 1985 , “ On the Mechanics of Fatigue Crack Growth Due to Contact Loading ,” Proc. R. Soc., London, Ser. A , A397 , pp. 197 – 209 . Harris, T. A., 1991...

... , the magnitude necessary for fatigue crack initiation within 10 7 cycles in aluminum alloys 9 . This is consistent with observations in practice 21 , where cracks are known to initiate after a few thousand cycles for the Δ σ = 90   MPa cyclic stress range. In the presence...

... service conditions. Fatigue cracks and delamination developed in bearings tested in a knee simulator and in rolling/sliding test specimens, and the damage was similar to that found in retrieved tibial bearings. The fatigue cracks invariably initiated in the embrittled oxidized layer, and the depth...