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Contamination of titanium by oxygen is inevitable during its processing by powder metallurgy (PM). When dissolved interstitially in the crystal lattice of titanium, oxygen exerts a great influence on strength and other mechanical properties. In this paper we investigated the effects of milling and sintering of titanium hydride powders on the levels of oxygen in sintered samples. To minimize contamination, milling was carried out under argon atmosphere and the manipulation of powders was performed inside a glove box. Samples were milled at two different particles sizes, isostatically pressed and sintered at 1000°C and 1200°C. The results indicated that the oxygen content in the final samples is mainly influenced by the level of oxygen in the starting powders and the particle size of these powders.

To meet the increasingly high NVH consumer and product requirements, it is necessary to obtain maximum dynamic performance of the vehicle structure. For such superior properties, e.g. strength, stiffness, and weight, there are several methodologies, such as parameter optimization (useful for fine adjustments), topology optimization (limited by manufacturing processes), and shape optimization of structural plates. Among the shape optimization methods, the method of embossed patterns allows large gains in structural stiffness as a result of imposing small deformations in the shape of the sheet metal. However, the method has limited applicability because it depends on weighting factors whose choice criterion is an open problem, with no closed solution, depending on methodologies such as the DoE (Design of Experiments) for its definition.

The rapid cooling in quenching heat treatment results in thermal stresses due to high thermal gradients. Thermal residual stresses can potentially affect the martensitic transformation as well the distortions. Distortion is one of the main problems of manufacturing and heat treatment is the main cause of this phenomena. It is known, that the quenchant agitation is a parameter that influences the cooling rates and consequently the residual stresses and distortions. In this way this work proposes to quench an AISI 5160 steel in three different levels of agitation, a conventional mineral oil at the same temperature. Cooling curves analysis, finite element simulation and metallographic observation support the obtained conclusions. It is found that a moderate agitation rate produces better results in terms of distortion and thermal residual stresses.

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.