Statistical Fracture of Brittle Materials; Progress on J. O. 5628 during FY 75 and Plans for FY 76.

摘要

The reasons why an improved understanding of the statistics of failure of brittle materials is important to the armed services are briefly reviewed. In addition, the status of work at Aerospace prior to undertaking the present work, which is supported by the Office of Naval Research and the Air Force Office of Scientific Research, and the technical proposal are reviewed. The tasks accomplished in FY 75 are discussed in some detail in Section II, subject to the limitation that this report was prepared two months prior to the end of the fiscal year. The major items of interest are: (1) a literature search for fracture data useful for validating or correcting theories, (2) recent discoveries that relate the theory for surface-distributed cracks to that for volume-distributed cracks, (3) work on the graphite model of Buch, Zimmer, and Meyer, (4) effects of porosity and crack interaction, and (5) the significance of asymptotic forms (such as the Weibull theory) in extreme value statistics.