Multiaxial Damage Parameter Based on Critical Plane Approach for Low Cycle Fatigue

To predict life of multiaxial low cycle fatigue more conveniently,a multiaxial low cycle fatigue damage parameter is proposed based on the crack extension characteristics and changes of the maximum shear strain and the corresponding normal strain on the maximum shear stain plane and the maximum shear strain plane is considered as the critical plane.The maximum shear strain and corresponding normal strain are selected as the basic damage parameters for low fatigue.The life prediction is proceeded by using the model with GH4169 alloy and 45 steel.The results showed that the error between life prediction and experimental results is basically within 2 factors.