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Shape Memory Alloys (SMA) are novel materials which have the ability to return to a predetermined shape when heated. SMA are useful as actuators which are materials that change shape, stiffness, position, natural frequency, and other mechanical characteristics in response to temperature or electromagnetic fields. Applications include engines in cars and airplanes, electrical generators and surgical implants that make use of the mechanical energy resulting from the shape transformations. Powder metallurgy allows the SMA production with savings of energy and time and with higher microstructural homogeneity than those obtained by conventional processes. In this work a new nickel-free titanium alloy Ti-22Nb-6Zr (%at) was produced in order to expand the application field of SMA. Samples were produced by mixing of initial metallic powders followed by uniaxial and cold isostatic pressing with subsequent densification by sintering between 800-1600°C, in vacuum.

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.