Effect of temperature and pressure on the properties of titanium alloy Ti-6Aℓ-4V produced from powder metallurgy

ABSTRACT

Were characterized microstructurally and mechanically the Ti-6Aℓ-4V alloy obtained through powder metallurgy in an uncontrolled atmosphere, varying the sintering parameters, arose. The samples were compacted in a uniaxial press at 874 MPa, 999 MPa, and 1124 MPa, and sintered without a protective atmosphere or vacuum, at 675 °C, 750 °C, and 850 °C. When sintering the material, the oxides influenced the results due to titanium’s high affinity for interstitial elements, promoting increased density and high hardness values. Based on the results, the treatment carried out at a pressure of 1124 MPa and a temperature of 750 °C showed the highest hardness in the beta phase (β), with a value of 1165.1 HV. In the alpha phase (α), the highest value was 1321.3 HV, presented by the treatment performed at a pressure of 999 MPa and a temperature of 850 °C. The high hardness values observed in the alloy are associated with the reinforcement promoted by the dissolution of Fe atoms. Materials with high hardness values use in the aerospace and biomedical industries, which always look for better mechanical resistance results, thus increasing their products’ useful life and applicability.

Keywords
Foundry processes; Sintering; Porosity; Metal alloys