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Applying the Heat Tinting Technique the microestrutural characterization of a 300M steel (medium carbon steel) was accomplished. The steel was austenitized for 20 min to 900°C, followed by holding at 400°C (in the bainitic temperature), with maintenance time of the material in the temperature of 1min, 5min and 30min, aiming at the formation of a multiphase structure. Through the metallographic analysis it is verified that, with the use of this technique, it is possible the determination of the volume fraction of the present phases in the 300M steel, especially in the identification and quantification of the retained austenite.

Titanium and its alloys provide high strength-to-weight ratios, good fatigue strength and increased corrosion resistance compared with others materials. Its acceptance in aerospace has been limited by costs considerations such as high cost of raw material, high buy-to-fly ratios and expensive machining operations. Significant cost reductions can be obtained by vacuum sintering and powder metallurgy (P/M) techniques by producing near net shapes and consequently minimizing material waste and machining time. The Ti 35Nb alloy exhibit a low modulus of elasticity. Stemming from the unique combination of high strength, low modulus of elasticity and low density, this alloy is intrinsically more resistant to shock and explosion damages than most other engineering materials. Samples were produced by mixing of initial metallic powders followed by uniaxial and cold isostatic pressing with subsequent densification by sintering between 900 and 1600 °C, in vacuum.

The dual-phase are produced by intercritical heat treatment and, getting a microstructure composed, basically, by ferrite and martensite, are detached by introduce typical characteristcs like high tensile strength, good ductility and conformability high rate of work-hardening and low yield stress. In the present work was studied the tensile behaviour of dual-phase steel in several conditions of tempering, with the purpose to investigate the ferrite - martensite interaction. The influence of different temperatures, used on the heat treatment, about the mechanical properties was related with microstructural parameters, like volumetric fraction, microhardness and phase morphology. The results showed that tempering caused reductions on martensitic volumetric fraction and phases microhardness, changing the dual-phase steels morphology. Furthermore, the elevation of tempering temperature occasioned a decreased on tensile strength levels and an increased on ductility.