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A new high-cycle fatigue criterion based on the critical plane approach is
proposed in this paper. Unlike most of the other multiaxial fatigue criteria based
on the critical plane approach, the critical plane is obtained by 3D analysis of
stress states. Also, the old critical plane criteria are modified in order to predict
life assessment especially for three-dimensional stress fields. Furthermore, a
variable critical plane concept is introduced and a new life assessment algorithm
is presented. The stress analysis is carried out in the finite element method to
achieve both computational efficiency and accuracy. The prediction life is
obtained with MALTAB software based on new method. Finally, experimental
fatigue lives are compared with prediction life by modified multiaxial fatigue
criteria. Experimental results are prepared for both proportional and nonproportional
cases. The results especially the results of orientation of critical
planes in variable conditions are discussed in this paper.