Fatigue Crack Propagation Life Prediction of GH4169 Under Biaxial Load Based on Cruciform Specimen

Aero-engine components have complex geometries and are subjected to various cyclic loads, so they are often in a multi-axial complex stress state during service. It is of great engineering significance to study the multiaxial fatigue properties of nickel-based alloy materials for aero-engines. This paper analyzed the fatigue failure mechanism of nickel-based alloys under biaxial load. The fatigue life can be divided into two parts: fatigue crack initiation life and fatigue crack propagation life. The fatigue crack growth life was predicted by the fatigue crack growth rate model based on the Paris formula. In addition, based on the scaling and superposition theory, the expression of the stress intensity factor K at the crack tip of the cruciform specimen was calculated. In this paper, the first crack that appears in the cross-shaped specimen was used for life prediction.