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Gamma Ti-Al (γ Ti-Al) has excellent mechanical properties and oxidation/corrosion resistance at elevated temperatures (above 700°C), which makes it a possible replacement for traditional Ni based superalloy components in aircraft turbine engines and in orbital platform vehicles. The alloy design and efficient routes of TiAl processing are important technological challenges. In this work, samples of Ti-48Al-2Cr-2Nb (at.%) were produced by powder metallurgy processes. Using powder metallurgy, samples were prepared from elemental and pre-alloyed powders mixed for 2 h, followed by cold uniaxial and isostatic pressing and sintered between 1100°C up to 1400°C, for 1 h, under vacuum. After metallographic preparation, samples were characterized by SEM (Scanning Electron Microscopy), X-ray diffraction (XRD), density analyses and Vickers microhardness measurements.

Contamination of titanium by oxygen is inevitable during its processing by powder metallurgy (PM). When dissolved interstitially in the crystal lattice of titanium, oxygen exerts a great influence on strength and other mechanical properties. In this paper we investigated the effects of milling and sintering of titanium hydride powders on the levels of oxygen in sintered samples. To minimize contamination, milling was carried out under argon atmosphere and the manipulation of powders was performed inside a glove box. Samples were milled at two different particles sizes, isostatically pressed and sintered at 1000°C and 1200°C. The results indicated that the oxygen content in the final samples is mainly influenced by the level of oxygen in the starting powders and the particle size of these powders.

It is observed an increasing interest in using titanium nitride (TiN) coatings to improve the wear properties of Ti alloys. An important method is the Electron Beam Physical Vapor Deposition (EBPVD) that is a form of deposition in which a target anode is bombarded with an electron beam given off by a charged tungsten filament under high vacuum, producing a thin film in a substrate. In this work are presented results of the target and substrate production using Ti (C.P.), Ti-6Al-4V and Ti-13Nb-13Zr by powder metallurgy. Samples were produced by mixing of initial metallic powders followed by uniaxial and cold isostatic pressing with subsequent densification by sintering between 900 to 1500 °C, in vacuum. Sintered samples were characterized for phase composition, microstructure and microhardness by X-ray diffraction, scanning electron microscopy and Vickers indentation, respectively. It was shown that the samples were sintered to high densities and presented homogeneous microstructure.