Study on Crack Component Fatigue Life Analysis Based on SIF Fitting
The present structure crack analysis method simplifies the crack as type I crack, and put the stress intensity factor (SIF) mathematical expression of infinite plate under the bi-directional even stress load into Paris formula to analyse the fatigue life of crack components. Due to the finiteness and complexity of component shape and the nonuniformity of the stress distribution in the engineering practice, which makes the SIF value inaccuracy according to the present method, so that the result of crack fatigue life has a large error. Considering the shortcomings of the method, this paper offers a new method which is using the finite element method to calculate SIF in different crack length directly. By means of function fitting, this method determines the mathematical relation between SIF and the crack length and changes the form of Paris formula based on the relation. Furthermore, it can analyse the fatigue life of crack components and improve the analysis accuracy theoretically.
Y. Chen and Y. T. Sun, "Study on Crack Component Fatigue Life Analysis Based on SIF Fitting", Applied Mechanics and Materials, Vols. 229-231, pp. 656-660, 2012