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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.

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.

The aim of this paper is to analyze the microstructural development in samples of Ti-48Al-2Cr-2Nb (at.%) alloys obtained by powder metallurgy (P/M). This alloy has potential applications when high operating temperatures are required, e. g. turbines, aerospace applications, automotive engines valves and turbocharger rotors. The elementary powders were mixed for 1 hour, cold uniaxially pressed at 60 MPa and sintered at 1100°C, for 1 hour, under vacuum. Then, the specimens were milled and submitted to a second stage that included cold isostatic pressing (400 MPa) with subsequent hot uniaxial pressing (20 MPa), between 900 up to 1200°C, for 2 hours, in argon atmosphere. The alloys were characterized by XRD (X-ray diffraction), SEM (Scanning Electron Microscopy), EDS (Energy Dispersive Spectroscopy) and Vickers microhardness measurements. The results indicated the viability of the route and the tendency of a lamellar microstructure in high sintering temperatures.

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 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 use of alternative materials in automotive production can lead to both significant weight reductions and oftentimes functional improvements as well. Titanium and its alloys have unique properties that enable its use in the aerospace industry like its high strength-to-weight ratio, good resistance to many corrosive environments, and can be used over a wide range of temperatures. Despite these high expectations and the numerous advantages of titanium materials, their use has always failed just for a single reason: price. Powder metallurgy (P/M) of titanium and Ti-based alloys may lead to the obtainment of components having weak-to-absent textures, uniform grain structure and higher homogeneity at lower costs (a necessary prerequisite to expand the use of titanium and its alloys) compared with conventional wrought products. In this work Ti-6Al-4V and Ti-48Al-2Cr-2Nb (γTi-Al) were produced by P/M in order to expand the application in automotive area.

Titanium alloys have been widely used in manufacturing of fans, compressor disks, and blades of advanced aircraft engines. However, titanium alloys are very sensitive to fretting fatigue damage, which may affect the safe reliability of the aircraft engine compressor. The multilayer coatings seem to be the most promising coating concept due to many requirements (e.g. multifunctional character, moderate residual stresses, good adherence to metallic substrates, proper hardness to toughness ratio and low friction coefficients) for titanium alloys exposed to complex wear conditions. This work aims the development of techniques for production of Ti/TiN multilayer coatings by Electron Beam Physical Vapor Deposition (EB-PVD) in order to define the influence of the number and thickness of the layers in the surface hardness of Ti-13Nb-13Zr alloy produced by powder metallurgy (P/M) from elemental hydrides.

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.