A fracture criterion for blunted V-notched samples

摘要

This paper shows how the cohesive zone model can help in predicting fracture loads of brittle components with blunted V-notches. Linear Elastic Fracture Mechanics cannot be applied in such cases because there are no singularities; there is no crack, and neither is the notch sharp. Numerical predictions based on the cohesive zone model were checked succesfully against experimental measurements for PMMA at -60 deg C (made by the authors) and steel, zirconia, silicon nitride and alumina by other researchers. The concept of a critical stress concentration factor, well established for sharp V-notches, is generalized, under certain circumstances, to blunted V-notches, and a non dimensional formulation of the fracture criterion is proposed.