A Kinetic Approach to Fracture of Solids III. The Statistical Features of the Time to Break (Longevity). Homogeneous Material

The statistical features of longevity are determined by two factors: by the random character of the thermally activated nucleation and propagation of the main crack and by the inhomogeneities of the structure of the sample. The shape of the distribution function of the longevities of homogeneous samples and its dependence on the size of the sample are calculated. This distribution and the experimentally observed distribution of brittle strengths are both described by Weibull's function. On the basis of this coincidence the analogy between fracture under prolonged load and brittle fracture is discussed.