Method for predicting fatigue life of silicon nitride combined silicon carbide refractory ceramic

The invention discloses a method for predicting the fatigue life of silicon nitride combined silicon carbide refractory ceramic. According to the method, indeterminate influence factors such as mean load, load gradient, size effect and fatigue limit of a material are comprehensive considered, and a stress concentration condition of a primary defect under the effect of an alternating load is adequately presented; by combining actual working conditions with an improved crack growth formula-Forman formula, a fuzzy theory is combined with a classical Miner linear damage accumulation method, and a prediction model for the crack formation life and the crack expansion life of the silicon nitride combined silicon carbide refractory ceramic is established under the effect of a complex load. According to the method, the prediction precision of the fatigue life of a ceramic material is increased micro-macro aspects, and the errors in the life prediction of a traditional fragile ceramic material are greatly reduced, so t