X-ray and Neutron Diffraction Study of Nanocrystalline Ti−Ru−Fe−O Compounds

Abstract

The effect of adding oxygen on the structure of nanocrystalline Ti−Ru−Fe compounds obtained by high-energy ball-milling has been studied by X-ray and neutron diffraction using a Rietveld refinement analysis. It is shown that oxygen atoms readily oxidize Ti to form various types of titanium oxides depending on the oxygen content. In each case, a simple cubic structure (cP2-CsCl) is also formed during milling but with a concentration higher than expected on the basis of various reaction schemes. Through a detailed analysis of the neutron and X-ray diffraction peaks, it is shown that the 1a site of the CsCl-type unit cell is depleted from Ti atoms by preferential substitution with Fe. At high oxygen concentration, the alloy is a multiphase material containing Ti2-xRu1+yFe1+z, Ti oxides, Ru, and Fe.