Quantitative Strength Prediction of Advanced Ceramics With Regular/Irregular Flaws in I-Mode Condition

Abstract Flaws in ceramics have significant impacts on strength. Understanding of ceramic strength from qualitative statistical description to quantitative prediction is essential for the fields of fracture mechanics, materials science and engineering applications. In this study, two regular flaw-strength prediction models with clear physical meanings were firstly established according to the classic crack-strength model (Sato [17] combined with two kinds of relationships between critical stress intensity factor Kc and tip radius r (Gomez [18] and Yang [19] under I-mode failure condition. Comparisons with the data that reported in the literature proved that the Sato-Yang model was more accurate than the Sato-Gomez model in evaluating fracture strength in ceramics with regular flaws. Based on the finite element simulation and the mathematical fitting, a simple coefficient that can reasonably described the complexity of flaw shapes was proposed, thus extending the regular flaw-strength model to solve the irregular flaw problem and passing the experimental verification at the same time.