A phase equilibria study and thermodynamic assessment of the BaO–Al2O3 system

Phase equilibria study and thermodynamic description of the BaO‐CaO‐Al2O3 system

“…Based on the previous work by Zhang and Taskinen, the BaO‐Al 2 O 3 system was reassessed and the calculated phase diagram can be seen in Figure A. As the phases B 7 A, B 4 A, and B 3 A rather than B 8 A were confirmed in the BaO‐rich region by Zhang and Taskinen, they were taken into account in the extrapolation into ternary system. BaO‐CaO and CaO‐Al 2 O 3 were calculated according to the database outlined by Zhang et al and MTOX oxide database, respectively, as displayed in Figure B,C.…”

“…Based on the previous work by Zhang and Taskinen, 8 the BaO-Al 2 O 3 system was reassessed and the calculated phase diagram can be seen in Figure 1A. As the phases B 7 A, B 4 A, and B 3 A rather than B 8 A were confirmed in the BaO-rich region by Zhang and Taskinen, 8 they were taken into account in the extrapolation into ternary system.…”

“…The three binary systems, BaO‐CaO, BaO‐Al 2 O 3 and CaO‐Al 2 O 3 , have been extensively studied by experiments and thermodynamic modeling, however, a large discrepancy in the liquidus and eutectic temperature exists in the BaO‐CaO system, as a result of the high melting points of the two components. A recent literature review and thermodynamic modeling of the BaO‐CaO system can be found in the work by Zhang et al, whereas the BaO‐Al 2 O 3 system has been previously described by Purt and Zhang and Taskinen based on the experimental and thermodynamic assessments. The CaO‐Al 2 O 3 system has been evaluated by several authors, Hallstedt and Mao et al, as well as measured by Nurse et al and Nityanand and Fine .…”

“…Considering the universal presence of water in most industrial and geological processes, the C 12 A 7 phase was taken into account in the present work for practical applications. Based on the thermodynamic parameters presented by Zhang et al, 6 Zhang and Taskinen, 8 and MTOX oxide database, 5 the phase diagrams of the binary BaO-Al 2 O 3 , BaO-CaO, and CaO-Al 2 O 3 systems were calculated, as can be seen in Figure 1.…”

“…The present work aims at (i) experimentally investigating the phase equilibria of the BaO-CaO-Al 2 O 3 system at 1500°C, (ii) verifying the controversial existence of the ternary compound, BaCa 2 Al 8 O 15 , (iii) critically reviewing the literature data available, and (iv) performing a thermodynamic assessment of the BaO-CaO-Al 2 O 3 system by assessment of the three binary systems which can then be extrapolated into a ternary system. For the sake of simplicity, BaO, CaO, and Al 2 O 3 are abbreviated to B, C, and A, thus B 7 A, B 4 A, B 3 A, B 8 A, BA, BA 6 , CA 6…”