Critical Crack Length for the Initiation of Unstable Propagation in Relation to Fracture Toughness and the Evaluation of Stress and Deformation Characteristics Obtained From Tensile Testing

Abstract

The paper is concerned with the relation between temperature and critical crack length for the initiation of a brittle crack unstable propagation at the yield strength level stress. For the purpose of calculation, results of dynamic fracture toughness test were applied; the experiment was supplemented with measuring stress and deformation characteristics in a determined test temperature range. For comprehensive assessment of test temperature effects, a fractographic analysis of fracture surfaces was conducted.