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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.

The production of multilayer allows the insertion of several interfaces over a substrate. The technological applications of the multilayer coatings involve optical, electromagnetism and wear areas. This paper aims the development of techniques for production of multilayer coatings with titanium nitride (TiN) and zirconium nitride (ZrN) obtained by Physical Vapor Deposition (PVD) from the use of an electron beam furnace. Moreover, the work includes the production of substrates (samples of Ti-35Nb-7Zr-5Ta) obtained by powder metallurgy from elemental hydrides and targets of Ti and Zr. The substrates were produced by mixing the elemental powders with subsequent steps of cold pressing and sintering at 1400°C in vacuum. The coatings were characterized by optical microscope, scanning electron microscope (SEM), chemical analysis via energy dispersive spectrometry (EDS) and Vickers indentation.

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.

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.