Strength-probability-time (SPT) relationships in ceramics
Tóm tắt
The concept of the SPT diagram for ceramics is introduced as an essential aid to the design engineer when using engineering ceramics. For given conditions of stress state and distribution, environment, temperature and component size, the diagram enables estimates of a safe working stress to be made for specific component lifetimes and survival probabilities. The theory underlying the SPT diagram is reviewed. This involves the merging of the concepts of statistical variations in strength, with sub-critical crack growth which leads to delayed fracture. It is shown how the SPT diagram can be generated by simple measurements of the strain rate dependence of fracture strength. Data for the delayed fracture of alumina are used to demonstrate the reliability of SPT diagram.
Tài liệu tham khảo
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