Fracture Assessment of Blunt V-Notched Graphite Specimens by Means of the Strain Energy Density

The main aim of the present work is to check the suitability of the brittle fracture model, namely the local strain energy density (SED), in predicting the experimental results on mode I fracture of blunt V-notched graphite components. For this purpose, a wide range of test results reported in the recent literature on brittle fracture of V-notched test specimens characterized by different geometries is considered. The specimens are made of the same type of coarse-grained polycrystalline graphite. The fracture assessment is carried out predicting theoretically the fracture loads by means of the SED criterion. The SED parameter is evaluated by averaging the local energy over a well-defined control volume which embraces the notch edge. It is found that the SED criterion allows assessing the fracture behavior of graphite specimens characterized by different notch angles and tip radii.