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

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. (C) 2019 Elsevier B.V. All rights reserved.