Abstract
The solubilities of titanium and carbon in Fe-Csat-Ti alloys were determined at temperatures from 1300°C to 1500°C. Some of the previously reported solubility values of titanium were determined by measuring the acid-soluble titanium contained in rapidly cooled samples in which the sedimentation of titanium carbide was inevitable. This sedimentation resulted in the difficulty in determining the accurate solubility of titanium. In order to overcome the difficulty, two methods were newly devised to measure the total titanium content in rapidly cooled samples.
The results obtained were as follows:
(1) The solubility of titanium at temperatures from 1300°C to 1500°C was expressed as, log[%Ti]=(-6760/T)+3.965
(2) By the use of the carbon solubility at different contents of titanium, the temperature dependence of interaction coefficient, eCTi, at temperatures from 1350°C to 1500°C was determined as,
eCTi=(-221/T)-0.072
(3) The change of standard Gibbs free energy for the reaction, Ti+Csat=TiC(s), was obtained as ΔG°=-30500+13.3T
