On the applicability of multiaxial high cycle fatigue criteria to metallic materials

Roberta A Gonçalves,Marcos V Pereira,Fathi A Darwish,G Hénaff

doi:10.1051/matecconf/201816516013

Abstract

A comparative study is made of the applicability of critical plane based multiaxial high cycle fatigue models to predicting the fatigue behavior of metallic materials. A number of models, namely Matake, McDiarmid, Carpinteri and Spagnoli, Liu and Mahadevan and Papadopoulos, were applied to fatigue limit states, involving synchronous fully reversed in-phase sinusoidal bend and torsion loading. The results obtained indicated a good predictive capability of the models with an average error index situated approximately between -5,5% and 4,5%. However, this average was limited to less than 3% for the latter three models. Finally, the critical plane orientation, which, for a given material, is characteristic of the proper model, is compared with that of the fracture plane, exclusively determined by the ratio between the shear stress and normal stress amplitudes.

Highlights

High cycle fatigue under uniaxial loading has shown that many metallic materials possess a fatigue limit, which means that they can sustain a very high number of cycles without fatigue failure
The fracture plane and critical plane orientations, defined by the angle ψψff, and ψψcc are listed in Tables 2 and 3, in terms of σσaa and ττaa, for the variety of materials indicated in the tables
For a given loading condition, the critical plane orientation depends on the adapted multiaxial fatigue criterion

Summary

Introduction

High cycle fatigue under uniaxial loading has shown that many metallic materials possess a fatigue limit, which means that they can sustain a very high (theoretically infinite) number of cycles without fatigue failure. Over many decades of research, a large number of models have been proposed to predict fatigue failure under multiaxial loading conditions. Whereas the use of Papadopoulos criterion requires only knowing the applied stress amplitudes, the other models depend for their application on the prior identification of the critical plane, where fatigue damage can occur leading to crack nucleation. Assuming that the critical plane is already known, the normal and shear stress amplitudes can be determined and fatigue failure assessment can be presented in the form of inequality. As the fatigue criteria in question are to be applied simultaneously to a given loading condition, a comparison of the error index involved is expected to provide a good assessment of their predictive capabilities in defining the fatigue behavior. The critical plane orientation, determined for each model, is presented in comparison with that of the fracture plane, for the loading conditions involved

High cycle multiaxial fatigue criteria

Critical plane identification

Results and discussion

Conclusion