Case study of multiaxial criteria for rolling contact fatigue of bearing steels

Abstract

Abstract.A rolling contact fatigue (RCF) differs from the classic fatigue in a stress-state. Nowadays, a prediction of the RCF is still not on the sufficient level. A lot of researchers tried to apply different multiaxial fatigue criteria (MFC) to the RCF, respectively they modified some or even proposed new one. Our paper focuses on assessment of bearing life estimation based on mentioned methods with experimental validation in laboratory. Comparison and summarization of different methods used in MFC life estimation is presented, with inclusion of fatigue material properties, hardness and probability. Mainly bearing steels are used for evaluation and region of high-cycle and giga-cycle fatigue.

Coupled Numerical Method for Rolling Contact Fatigue Analysis

“…According to the literature [14] and [17], in the hardest layers in our case, this ratio is 1.25 and 1 + ν, respectively, where ν is the Poisson's factor, which can vary between 0.25 and 0.33.…”

“…As stated above, in the case of the machine elements examined here, a long or ultra-high cycle life must be expected, during which one cannot expect a significant (plastic) deformation from cycle to cycle. Thus, for this typically stress-controlled lifetime estimate, one can use the S-N curve, which is typically given by the Basquin equation [14].…”

A life prediction model for rolling contact fatigue based on the improved moment of load path method

“…The load paths of the multiaxial stress state in Bomas et al 24 are cyclic tension and torsion with a phase shift of 90°, as shown in Figure 11A. The RCF life data with 50% survival probability of the bearing steel are obtained in previous studies 8,25–27 under point contact conditions, and the loading conditions consist of maximum Hertz pressure 4.2 GPa, 27 4.5 GPa (test data in Fu et al 27 marked as 4.5A and Cao et al 25 marked as 4.5B), 5 GPa, 8 and 5.3GPa 26 . The FEM model in Section 2.1 is used to determine the stress state of the dangerous region, and the load path of the dangerous element is plotted as shown in Figure 11B.…”

“…Finally, the IMLP model is applied to estimate the bearing steel GCr15 life of multiaxial stress fatigue 24 and RCF 8,25–27 . The load paths of the multiaxial stress state in Bomas et al 24 are cyclic tension and torsion with a phase shift of 90°, as shown in Figure 11A.…”

“…The Von Mises or maximum orthogonal shear stress of the subsurface material element is considered the critical stress parameter in these models. However, the above stress parameters are insufficient to characterize the damage to the material caused by the complex subsurface stress under rolling contact conditions, and some stress parameters based on multiaxial criteria were proposed for the life prediction of RCF 7,8 …”