The Analysis of Interrelation between Kinetics of Propagation of Plastic Deformation and Initiation of Ductile Fracture

The work analyses a nature of interrelation between kinetics of propagation of plastic deformation and initiation of ductile fracture for low-carbon microalloyed steel 06Kh1. To reach the purpose of the work, the experiment is carried out. It includes stretching of a series of samples with deformation deceleration after reaching a certain level of loading. The study of the corresponding samples shows that the stage of crack origination is made through blocking the propagation of spreading the plastic deformation by the separation surfaces of the general and special types. At the same time, it is determined that the second stage (growth of microcracks) develops due to the simultaneous action of two mechanisms: accumulation of dislocations (the Cottrell model) and aggregation of several microcracks into single one.