Predicting Fatigue Crack Initiation Life of Plate-Like Component by Damage Mechanics and Finite Element Method

Abstract

Applied fatigue damage mechanics and finite element method to study the fatigue crack initiation life problems of component. Fatigue crack initiation life is obtained by using the method of additional load, just a stiffness matrix calculation, greatly reducing the workload of calculation. With the damage degree of the critical element partitioning step of the damage evolution, the damage degree increases unceasingly obtains the corresponding, corresponding to the stress field, strain field and the load matrix, and then to calculate the equivalent stress, the application of damage evolution equation for calculating fatigue crack forming life corresponding. Until the damage degree of the critical element to 1 so far, the fatigue crack initiation life is obtained by adding the fatigue crack initiation lives with different damage variable.