ThermoCalc Modelling of the Effect of Chemical Composition on the Phase Transformations Temperatures of Ti-0.4Al Alloy

Abstract

The effect of chemical composition of Ti-0.4 Al α-titanium alloy (PT-1M alloy) on the phase transformation temperatures up to melting temperature has been investigated using ThermoCalc software. The possibility of appearance of Ti2N nitride, Tix(CN)-type carbonitride, and Ti2Fe-type intermetallic in the alloy structure in equilibrium state has been proved by thermodynamic calculations. It has been proposed the so-called aluminum equivalent (Aleq) for PT-1M alloy to analyze the effect of chemical composition on the phase transformation temperatures change. The following equivalents have been suggested: AleqTβ for β↔(β+α)- transformation, AleqTliq for L↔β-transformation, and AleqTsol for (L+β)↔β-transformation. It has been shown the linear correlation between the characteristic temperatures of phase transformations in the investigated alloy and the proposed aluminum equivalents. © Published under licence by IOP Publishing Ltd.