Evolution of Defect Structure of Two-Phase Titanium Alloy Under Active Load

Abstract

The paper deals with the defect structure of two-phase VT6 titanium alloy and studies its evolution under plastic deformation within the wide range. It is found that the defect structure of this alloy before loading is a multi-level system with such scale-level elements as grain, colony, lamella, α- and β-lamellas, microtwins, and dislocation substructure. During plastic deformation, the evolution of the dislocation subsystem is observed. The sequence of substructural transformations with deformation is identified in this paper. The scalar dislocation density is measured in both phases and its dependence on the degree of deformation is detected. In particular, it is shown that the fracture of VT6 titanium alloy is caused by the similar value of scalar dislocation density achieved both in α- and β-phases.