The Mechanism of Cleavage-Like Fracture for Ductile Materials under Stress Corrosion Cracking Based on the Analysis of the Interaction between a Macroscopic Crack, Dislocations and Hydrogen

摘要

Several mechanisms have been proposed to explain the behavior of stress corrosion cracking (SCC) such as dissolvent anodic chemical reaction and hydrogen embrittlement mechanisms. However the dominant factor of SCC has not yet been clarified under various experimental conditions. A discontinuous cleavage-like fracture has been sometimes observed in the fracture surface of ductile fcc alloys during SCC. However for these ductile materials, SCC is usually dominated by dissolvent anodic chemical reaction and inter-granular cracking can he observed. Therefore, the cause on the occurrence of cleavage-like fracture for these ductile materials remains to he clarified. In this paper, we proposed stress corrosion cracking model on the basis of interaction of dislocation and hydrogen around a crack tip to predict discontinuous cleavage-like fracture during SCC for ductile fcc alloys and the feasibility of the occurrence of cleavage-like fracture was clarified.