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Titanium and titanium alloys are excellent candidates for aerospace and surgical implants applications owing to their high strength to weight ratio and good corrosion resistance. Among the titanium alloys recently developed, Ti-13Nb-13Zr is distinguished for presenting low modulus of elasticity, high mechanical resistance and superior biocompatibility, suitable for springs, bellows, surgical implants and aerospace parts with high resistance to shock and explosion damage. The alloys processing by powder metallurgy eases the obtainment of parts with complex geometry and near-net shape. In this work, results of the porosity control in the Ti-13Nb-13Zr alloy produced by powder metallurgy are presented. The 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 porosity level depends on the compaction pressures, sintering temperatures and holding times.

Titanium alloys parts are ideally suited for advanced aerospace systems, chemical and naval applications and surgical implants because of its high strength-to-weight ratio, high resistance to many corrosive environments, and can be used over a wide range of temperatures. Powder metallurgy of titanium and Ti-based alloys may lead to the obtainment of components having weak-to-absent textures, uniform grain structure and higher homogeneity compared with conventional wrought products. In this work, results of the densification of Ti-6Al-4V, Ti-6Al-7Nb and Ti-13Nb-13Zr alloys after cold and isostatic pressing with subsequent densification by sintering between 900-1400°C using hydride titanium powders are presented. The samples were characterized by X-ray diffraction, scanning electron microscopy, Vickers indentation and density measurements.

Titanium alloys parts are ideally suited for advanced aerospace systems because of their unique combination of high specific strength at both room temperature and moderately elevated temperature, in addition to excellent general corrosion resistance. Despite these attractive features, use of titanium alloys in engines and airframes is limited by cost. The alloys processing by powder metallurgy eases the obtainment of parts with complex geometry and probably, cheaper. In this work, results of the Ti-6A1-4V, Ti-6Al-7Nb and Ti-13Nb-13Zr alloys production are presented. Samples were produced by mixing of initial metallic powders followed by uniaxial and cold isostatic pressing with subsequent densification by sintering at 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. Density was measured by Archimedes method.

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.

Titanium alloys parts are ideally suited for advanced aerospace systems because of their unique combination of high specific strength and superior resistance to many corrosive environments, in addition to excellent composite compatibility. Despite these features, use of titanium alloys in engines and airframes is limited by cost. Therefore, the improvement of processing techniques for titanium alloys production became a trend of the modern metallurgic technology. This work presents results of the microstructural development of Ti-6Al-2Sn-4Zr-2Mo alloy produced by arc melting and powder metallurgy processes. This alloy has important applications in aerospace area, in sections exposed to high temperatures. Samples of this alloy were characterized by SEM (scanning electron microscopy), XRD (X-ray diffraction), Vickers microhardness measurements and density.

The automotive industry has identified several automobile components that could be replaced with titanium alloy components, either through direct replacement in existing designs or, preferably, in new designs to fully exploit the unique properties of titanium. The alloy processing by powder metallurgy (M/P) eases the obtainment of parts with complex geometry and, probably, cheaper. In this work, results of the Ti-35Zr-10Nb alloy production are presented. This alloy due to its high wear, impact and corrosion resistance is a promising candidate for automotive applications. 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. Sintering behavior was studied by means of dilatometry. Sintered samples were characterized for phase composition, microstructure and microhardness by X-ray diffraction, scanning electron microscopy and Vickers indentation, respectively.

Titanium and its alloys provide high strength-to-weight ratios, good fatigue strength and increased corrosion resistance compared with others materials. Its acceptance in aerospace has been limited by costs considerations such as high cost of raw material, high buy-to-fly ratios and expensive machining operations. Significant cost reductions can be obtained by vacuum sintering and powder metallurgy (P/M) techniques by producing near net shapes and consequently minimizing material waste and machining time. The Ti 35Nb alloy exhibit a low modulus of elasticity. Stemming from the unique combination of high strength, low modulus of elasticity and low density, this alloy is intrinsically more resistant to shock and explosion damages than most other engineering materials. Samples were produced by mixing of initial metallic powders followed by uniaxial and cold isostatic pressing with subsequent densification by sintering between 900 and 1600 °C, in vacuum.

Titanium alloys parts are ideally suited for advanced aerospace systems because of their unique combination of high specific strength at both room temperature and moderately elevated temperature, in addition to excellent corrosion resistance. Despite these features, use of titanium alloys in engines and airframes is limited by cost. The alloys processing by powder metallurgy (P/M) eases the obtainment of parts with complex geometry. In this work, results of the Ti-6Al-4V alloys production are presented. Samples were produced by mixing of initial metallic powders followed by uniaxial and cold isostatic pressing with subsequent densification by sintering between 900 up 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.