Thermodynamic Description of $${\hbox{SrO-Al}_{2}\hbox{O}_{3}}$$ System and Comparison with Similar Systems

Abstract

The Al 2 O 3 -SrO binary system has been studied using the CALPHAD technique in this paper. The modeling of Al 2 O 3 in the liquid phase is modified from the traditional formula with the liquid phase represented by the ionic two-sublattice model as (Al 3+ , Sr 2+ ) P ( AlO 1À 2 , O 2-) Q . Based on the measured phase equilibrium data and experimental thermodynamic properties, a set of thermodynamic functions has been optimized using an interactive computer-assisted analysis. The calculated results are compared with experimental data. A comparison between this system and similar systems is also given.

Chloride‐Ion‐Stabilized Strontium Mayenite: Expansion of Versatile Material Family

“…20 In practice, Sr 12 Al 14 O 32 Cl 2 decomposes at temperatures below the eutectic melting point of SrAl 2 O 4 and Sr 3 Al 2 O 6 (1560°C). 16 The Sr 12 Al 14 O 32 Cl 2 phases obtained in the present study were found to almost fully (e.g., 93% in Table I decreases in the amounts of SrCl 2 , confirming the evaporation of SrCl 2 , which preferentially occurred at >1300°C. The starting compositions examined in the present study are also plotted in Fig.…”

“…The residue is shared between Sr 3 Al 2 O 6 and SrAl 2 O 4 phases, which are eutectic equilibrium phases in the SrO-Al 2 O 3 pseudo-binary system. 16 Relative densities of samples after sintering at 1200°C and 1300°C for 6 h were 63% and 83%, respectively. They still have an open-pore microstructure.…”

“…15 However, the Sr-mayenite synthesized so far contains OH À ions in the cages, and is only a quasi-stable phase in the SrO-Al 2 O 3 pseudo-binary system. 16 Sr-mayenite with full OH À incorporation is described as [Sr 24 Al 28 12 Rigorous synthetic conditions are required, especially for the solid-state reaction route, where Sr-mayenite is never formed as the major phase when SrCO 3 or SrO is used as the Sr source, irrespective of the Al source and other reaction conditions. The establishment of easier synthetic routes with better thermal stabilities is an important step in material modifications by anion manipulation in Sr-mayenite-based materials.…”

Synthesis of a Violet Sr–Al–O:Eu2+ Phosphor Particle Using Elemental Al Diffusion

“…Sr–Al–O:Eu 2+ particles were synthesized using a molar ratio of (Sr, Eu) 7 Al 12 O x . From SrO‐Al 2 O 3 diagrams, it was clear that the SrAl 2 O 4 crystalline phase could be obtained if the composition ratio was changed such that the SrO/Al 2 O 3 ratio was 7:12 . Sr–Al–O phosphors are known to form several intermediate Sr–Al–O phases during synthesis .…”

Thermodynamic modeling of the Al–Si–Sr–O quaternary system

“…This description was further improved by introducing ternary interaction parameters according to the Al 2 O 3 eSrO pseudo binary system modeled by Ye et al [11]. The improved thermodynamic description was used to calculate phase diagrams as shown in Figs.…”