Temperature–Time–Transformation Diagrams Construction for Beta-Solidifying TiAl-Based Alloy in As-Cast Condition

Abstract

An experimental investigation of structure evolution kinetics in a new six-component TiAl-based alloy Ti-44.5Al-2V-1Nb-(0.5…L5)Zr/(L5…2.5)Cr-(0…0.1Gd) (at.%) with variable Zr, Cr, and Gd content has been accomplished under the conditions of high-temperature exposures in the temperature range 1000–1300°C and durations of 15–240 min. The Temperature – Time – Transformation diagrams have been constructed to summarize data on isothermal phase transformations for both Zr(+Gd)- and Cr(+Gd)-containing compositions with the initial as-cast structure. It is shown that the variation of Zr and Cr contents within the given limits for the studied alloy, as well as the doping with Gd microadditions in the amount of 0.1 at.% do not lead to any noticeable effect on the kinetics of structure behavior in isothermal conditions.