title: Mechanical properties and microstructural evolution of vacuum hot-pressed titanium and Ti-6Al-7Nb alloy.
abstract: Hot-pressing is a powder metallurgy process where loose powder is loaded into a mould, usually of graphite, and sintered by the simultaneous application of high temperature and pressure. In this study elemental titanium and Ti-6Al-7Nb alloy powders are hot-pressed under different conditions in order to study the influence of the processing parameters on the microstructure and mechanical properties. The samples are characterised in terms of relative density, microstructure, XRD, percentage of interstitials, three-point bending test and hardness. Relative densities as high as 99% are obtained, the oxygen and carbon content remains almost constant but nitrogen percentage increases. This is due to the interaction with the BN coated mould and leads to the formation of a reacted layer in the surface, composed by different titanium compounds, which greatly affect the mechanical properties. Nevertheless, the removal of this reacted layer leads to an important improvement of the ductility, especially for elemental titanium.
authors.affiliation: Department of Materials Science, Universidad Carlos III de Madrid, Avda. de la Universidad 30, E-28911 Leganés (Madrid), Spain. bolzoni.leandro@gmail.com
authors.forename: L
authors.initials: L
authors.lastname: Bolzoni
authors.forename: E M
authors.initials: EM
authors.lastname: Ruiz-Navas
authors.forename: E
authors.initials: E
authors.lastname: Neubauer
authors.forename: E
authors.initials: E
authors.lastname: Gordo
mesh_terms: D002244:Carbon / Q000737:chemistry; D004058:Diffusion; D006244:Hardness; D006358:Hot Temperature; D006801:Humans; D008422:Materials Testing; D009584:Nitrogen / Q000737:chemistry; D010100:Oxygen / Q000737:chemistry; D010316:Particle Size; D011208:Powders; D013314:Stress, Mechanical; D013499:Surface Properties; D013696:Temperature; D013718:Tensile Strength; D013816:Thermodynamics; D014025:Titanium / Q000737:chemistry*; D014618:Vacuum; D014961:X-Ray Diffraction
chemical_list: D011208:Powders; C070282:Ti-6Al-7Nb alloy; D002244:Carbon; D014025:Titanium; D009584:Nitrogen; D010100:Oxygen