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 pha ses of these systems are described with thermodynamic models, The mode ls were fitted to the experimental information and the resulting optim ized data sets are presented, The calculated thermodynamic properties of the two binary compounds HfB and HfB2 are compared with experimenta l 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 latt er, several isothermal sections, isopleths, and the liquidus surface a re included. They are presented and compared with the experimental inf ormation. A reaction scheme for the ternary Ti-Hf-B system was constru cted.