Effect of heat treatment of the P/M Ti-6Al-4V

Titanium alloys parts are ideally suited for advanced aerospace systems because of their unique combination of high specific strength at both room temperature and moderately elevated temperature, in addition to excellent corrosion resistance. Despite these features, use of titanium alloys in engines and airframes is limited by cost. The alloys processing by powder metallurgy eases the obtainment of parts with complex geometry. in this work results of the Ti-6Al-4V sintered alloy are presented Samples were produced by mixing of initial metallic powders followed by uniaxial and cold isostatic pressing with subsequent densification by sintering between 900 up to 1500 degrees C, in vacuum. Sintered samples were characterized for phase composition, microstructure and micro hardness by X-ray diffraction, scanning electron microscopy and Vickers indentation, respectively. It was shown that the samples were sintered to high densities and presented homogeneous microstructure from the elements dissolution with low interstitial pick-up. The influence of the solution treatment at 1050 degrees C, 950 degrees C and 800 degrees C with water or air cooling followed by aging treatment at 550 degrees C was investigated on the specimens from Ti-6Al-4V model titanium alloy. After the treatments 1050 degrees C/water and 950 degrees C/water alpha' martensite structure was created, in the other cases a lamellar structure of alpha + beta phases was formed.