Modelling Dilatometry Data of Isothermal ω-Phase Formation in a Strongly β-Stabilised TiV-Alloy

Abstract:

In the most relevant technical β-titanium alloys, the extensive formation of the metastable ω-phase during common heat treatments has been a long-standing problem due to the deteriorating effect of this phase on the material properties. By means of dilatometry, the formation of the isothermal ω-phase has been investigated during ageing a Ti-21at.-%V-sample at 300 °C. A model has been developed, which allows to quantitatively correlate the maximum length changes appearing upon ageing to changes occurring at the microscopic scale, i.e. variations of the lattice constants, phase fractions and concentrations of vanadium in the phases appearing. The length change predicted by the model is in very good accordance with the data measured paving the way for further kinetic discussion and ultimately for deriving kinetic parameters.

• Periodical: Materials Science Forum (Volume 1016)
• Pages: 1851-1856
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.1016.1851
• Online since: January 2021
• Authors: Robert Josef Enzinger*, Martin Luckabauer, Tetsu Ichitsubo, R. Würschum
• Keywords: Dilatometry, Isothermal ω-Phase Formation, Spinodale Decomposition, Titanium-Vanadium Alloy, β-Stabilised Titanium Alloy

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