Phase transformations in Zr under high-pressure and shear deformation treatment

In this paper, we present our structural studies of the high-purity Zr transformation under conditions of deformation under pressure; our research comprises two techniques: studies in a high-pressure shear cell, and during a hydrostatic extrusion process. In the samples pressure-treated under shear conditions, deformation bands were found and their orientation was determined. It was found that under two types of deformation used in the present work, only one of the two orientational relationships (OR) known in literature for the mutual orientation of the alpha- and omega-phases occurs, which is explained by the introduction of small amounts of oxygen into the alpha-lattice. In the process of shear deformation, oxygen penetrates into the Zr lattice, and baddeleyite-ZrO2 is formed. The mutual orientation of the alpha- and omega-phases with baddeleyite is established.