Abstract
The brittle fracture model for multiaxial tensile stresses was proposed and its applicability was studied by comparing experimental data. The proposed model can treat microstructures such as grain size and pore size in it, and the fracture probability can be calculated as a function of multiaxial stresses σ1, σ2, and σ3. As experimental data, two types of graphite such as IG-110 and PGX were examined. From the comparison it was shown that the predicted strength agrees well with experimental data not only for the average strength but also for the strength distribution, and that predicted and experimental strengths were fit quite well to the Weibull statistical distribution. Moreover, by applying this model it was predicted that the multiaxial strength behavior would not depend on pore/grain microstructure and specimen volume.
