Keyword: «equal-channel angular pressing»

The changes of microstructure and resistance of steel 09G2S to brittle fracture after the "cold" (at room temperature) equal channel angular pressing (ECAP) were investigated. It is shown that getting of the nano and submicrocrystalline microstructures has provided a technically significant improvement in the mechanical and operational properties of the steel (strength, toughness), including at fall of tests temperature to –40 °C. The qualitative analysis of features of crack formation processes in nanostructured metal under dynamic loading was conducted. It was revealed that the high values of impact toughness are due to the implementation of energy–intensive micromechanisms of fracture – ductile dimpled fracture and dispersed quasi- cleavage, intensive branching of micro- and macrocracks, what caused the slowing of their velocity and the formation of a developed relief.