Critical assessment and thermodynamic calculation of the ternary system boron-hafnium-titanium (B-Hf-Ti)

Experimental work on the ternary system Ti-Hf-B as well as on the two binary boundary systems Hf-B and Ti-Hf is reviewed. The individual phases of these systems are described with thermodynamic models, The models were fitted to the experimental information and the resulting optimized data sets are presented, The calculated thermodynamic properties of the two binary compounds HfB and HfB2 are compared with experimental measurements, Phase diagrams were calculated for the binary systems Hf-B and Ti-Hf as well as for the ternary Ti-Hf-B system; for the latter, several isothermal sections, isopleths, and the liquidus surface are included. They are presented and compared with the experimental information. A reaction scheme for the ternary Ti-Hf-B system was constructed.