Constitution of titanium rich alloys of Ti–V–Fe–Al system

Abstract

An investigation has been made of the constitution of the titanium rich partial Ti–V–Fe–Al system in the composition range applicable to commercial α+β and β Ti–V–Fe–Al alloys (e.g. Ti–10V–2Fe–3Al alloy) and at temperatures between 650 and 800°C. Partial Ti–V–Fe isothermal sections for alloys containing ~4 wt-%Al and V and Fe in a ratio ≥1:1 show only α and β as the equilibrium phases for compositions up to 13 wt-%V and 4 wt-%Fe. The position of the α+β/β boundary is temperature dependent and its shape is affected by the amount of aluminium present in the β in equilibrium with a in the quaternary Ti–V–Fe–Al alloys. By contrast, the α/α+β boundary is independent of these parameters. Microstructural features relating to morphology and volume fractions of α and β phases have been investigated and, together with the compositions of α and β, are discussed in the context of alloy properties and processing.

MST/1323