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Materials with appropriate behavior at high temperatures and aggressive environments have become a scientific and technological necessity nowadays. Studies have been undertaken for improvement in getting new alloys, especially for the reevaluation of existing commercial alloys, through the acquisition of data under conditions of higher severity. In this context it was used for this work to Ti-6Al-4V in the form of cylindrical bars, provided forged and annealed at 190°C for 6 hours and cooled in air, which has favorable properties for aerospace application. The alloy after heat treatments to obtain the bimodal structures, martensite and Widmanstätten was subjected to creep tests at 600°C under the conditions of 250 and 319 MPa, in the form of constant load. The structures of Widmanstätten and martensite showed higher creep resistance in both stress conditions used in the trials.

The study of creep has a major importance when materials are submitted to high stress and homologous temperature. Superalloys are designed to operate under high stress, temperature and corrosion environment. Those properties of superalloys are due to high temperature stable matrix, solid solution elements and precipitated particles. This study aims to determine the creep resistance of Inconel 718 aged superalloy obtained through the tests according to ASTM E139-06, at stress range of 510 to 700 MPa and temperature of 675°C. The parameters as the primary creep time (tp), steady-state creep rate (εs), time to rupture (tr) and strain to rupture (εr) are important to evaluate the creep resistance. It used a scanning electron microscope (SEM) to obtain images of the fracture surface of specimens. The images of the fracture surface were investigated in order to relate the temperature of test with the fracture mechanism.

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.