Failure Criteria and Their Application Combined with System Structure Defects

Accurate failure prediction is a sharp focus issue in engineering application and advanced science. In it, the most important technique is to properly define the failure criteria. This work presents the critical stress intensity factor and the critical defect size in serving environment, both of which are essentially connected with the environmental surface energy and the environmental plastic deformation work. The defect is further identified as a unified feature to predict serving lifetime of the systems and quantitatively evaluate structural properties in theory and in engineering. Also, a case of defect analysis in aerospace safety is listed at the final.