Dehydrogenation of nanocrystalline TiH2 and consequent consolidation to form dense Ti

Abstract: Dehydrogenation of nanocrystalline TiH₂, produced by pulverization of commercially available powder, has been examined in detail by a combination of thermal analysis, X-ray diffraction (XRD), and transmission electron microscopy (TEM). The dehydrogenation to form Ti occurs as a two-step process involving the formation of an intermediate phase, TiH. In-situ experiments on dehydrogenation inside a transmission electron microscope reveal the possibility of a powder-metallurgy process for consolidation of Ti components by vacuum annealing of nanocrystalline TiH₂ at ∼0.5T _m , where T _m is the melting point of Ti. Near-full densification of Ti has been achieved by sintering nanocrystalline TiH₂ under vacuum at ∼0.5T _m .