Phase transformations in iron oxide–metal systems during intensive plastic deformation

Schemes of the dynamic dissolution of iron oxides in metallic Me (Fe, Ni, Cr, Ti, Al) matrices have been determined using Mِssbauer spectroscopic, X-ray diffraction, and transmission electron microscopic methods. It was shown that phase transformations of the hematite and the magnetite under compression shear (CS) at room temperature were accompanied by appearance of cation-deficient oxides and metallic solid solutions. The dissolution process depended on the ability of the metallic matrices to form solid solutions and chemical compounds with iron and oxygen. New structural forms of oxides, which presumably contained a high oxygen concentration, were found. It was hypothesised that oxide dispersion strengthened alloys could be prepared by CS of a mixture of iron oxides and metals.