The Analysis of Fracture Mechanisms of Ferritic Steel 13HMF at Low Temperatures

摘要

In this paper, the transition from a ductile fracture mechanism to a cleavage fracture mechanism is analyzed. Microscopic observations of the domains in front of a crack were followed by numerical analysis. The microscopic observations were accompanied by analysis of the fracture surfaces. Both the influences of temperature and an in-plane constraint on the mechanism transition were taken into account. The numerical analyses were carried out using two different models of a crack: Stationary and propagating. The direct, simultaneous influence of the level of the opening stress maximum, the characteristic distance in front of the crack tip, and the level of plastic strain on the ductile-cleavage transition have been confirmed.