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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.

In the aerospace industry, 80-90% of the titanium used in airframes has been from Ti-6Al-4V. This alloy is used throughout the section of an aircraft - fuselage, nacelles, landing gear, wing and empennage. In gas turbine engines Ti-6Al-4V is used in static and rotating components. Castings are used for the manufacture of more complex static components; forgings are typically used for moving parts. Conventional methods for obtaining titanium alloys require special conditions of controlled atmosphere that culminates in a high production cost. In this paper it was investigated the peculiarities of the typical microstructure of Ti-6Al-4V produced by powder metallurgy using TiH₂ powder. Samples were produced from the initial mixture of Al, V and TiH₂ powders, followed by cold uniaxial and isostatic pressing with subsequent densification by sintering in temperatures between 800-1400°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.