Experimental study and thermodynamic re-modelling of the constituent binaries and ternary B–Fe–Ti system

Abstract

In the present paper, the complete ternary B–Fe–Ti system is thermodynamically modelled based on our own experimental results and information reported in literature. Series of key experiments were performed for the binary Fe-B, Fe-Ti and the ternary B-Fe-Ti systems in order to obtain parameters of invariant reactions. For this, 19 alloys were prepared and analysed in the as-cast and annealed conditions by means of SEM/EDS, SEM/EBSD, XRD and DTA/DSC techniques. A new ternary boride Ti2FeB2 with the crystal structure of Mo2FeB2 (an ordered derivative of U3Si2 crystal structure type) was revealed to exist at temperatures from 1273 K to solidus. The elaborated thermodynamic description was applied to calculate selected phase equilibria as to provide a comparison between calculated and experimental results. The calculations are shown to reproduce available experimental data entirely well.