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Gamma-TiAl alloys are potential replacements for nickel alloys and conventional titanium alloys in hot sections of turbine engines, as well as in orbital platform vehicles. The combination of high specific stiffness and good oxidation resistance at intermediate temperatures can provide significant weight savings. However, they have a limited plasticity at room temperature and the tendency to brittle fracture. Powder metallurgy is a near net shape process that allows the parts production with complex geometry at low costs. An improved plasticity of the Ti-Al alloys is received by adding alloying elements and by microstructure modification. An alloy of two-phase structure Ti-48Al-2Cr-2Nb (at.%) was investigated using the blended elemental technique. Samples were produced by mixing of initial metallic powders followed by uniaxial and cold isostatic pressing with subsequent densification by sintering between 1100-1400°C, in vacuum.

Titanium alloys parts are ideally suited for advanced systems because of their unique combination of high specific and corrosion resistance. Ti-6Al-4V is the most important titanium alloy and its application ranges from aerospace to surgical implants. Despite these attractive features, use of titanium alloys is limited by cost. The alloys processing by powder metallurgy ease the obtainment of parts with complex geometry and probably, cheaper. In this work, new routes of Ti-6Al-4V production by powder metallurgy are investigated. Samples were produced by mixing of initial metallic powders followed by uniaxial and cold isostatic pressing with subsequent densification by sintering between 900-1400°C, in vacuum. Sintered samples were characterized for phase composition, microstructure and microhardness by X-ray diffraction, scanning electron microscopy and Vickers indentation, respectively. Density was measured by Archimedes method.

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.

The powder metallurgy allows titanium alloy production with savings of energy and time with higher microstructural homogeneity than those obtained by conventional processes. The processing of titanium alloys is increasing in industry, since these alloys presenting superior mechanical properties than commercially pure titanium. Ti-Zr alloys with zirconium contents ranging from 10 to 40 wt% have been investigated by melting process along the last years. In these alloys were reported characteristics as excellent corrosion resistance and high biocompatibility. In this work Ti-40Zr was produced by powder metallurgy in order to produce parts with complex geometry with high microstructural homogeneity to be applied in areas such as the space industry and surgical implants. Samples were produced by mixing of initial hydrided powders followed by uniaxial and cold isostatic pressing with subsequent densification by sintering between 800-1600 °C, in vacuum.