Calcium Hexaluminate and Its Stability Relations in the System CaO–Al₂O₃–SiO₂

Abstract

By a combination of solid-state sintering and quenching experiments the validity of calcium hexaluminate as a stable phase and the extent of its primary field in the system CaO-Al2O3-SiO2 have been established. The size of the primary field is considerably reduced from that suggested by earlier work. The anorthite-corundum-calcium hexaluminate invariant point has been relocated a t 28.070 CaO, 39.7% A1203, and 32.3%

Structure and non-stoichiometry of calcium aluminates

“…Adelskold (1937) examined magnetoplumbite and related isomorphous structures and proposed CA 6 as a stable phase. This was confirmed by Filonenko and Lavrov (1949) and later by Gentile and Foster (1963). The most recent phase diagram for the Ca0-Al 2 o 3 pseudo-binary system now includes c 3 A, CA, CA 2 and CA 6 (Nurse, et ~1 1956).…”

The first known natural occurrence of calcium monoaluminate, in a calcium‐aluminum‐rich inclusion from the CH chondrite Northwest Africa 470

“…Accordingly, the boundary curves separating these aluminates from one another (and hibonite from corundum, Cor) are reaction curves as indicated by the double arrows. Phase relationships are from Osborne and Muan (1960) and Gentile and Foster (1963), and modified slightly (dashed curve) to take account of the incongruent melting of CaA1204 as demonstrated in the recent work on the Ca0-AI2O3 join by Jerebtsov and Mikhailov (2001). Note the thermal divide on the gehlenite-grossite boundary curve (see text).…”

Temperature independent thermal expansivities of calcium aluminosilicate melts between 1150 and 1973K in the system anorthite–wollastonite–gehlenite (An–Wo–Geh): A density model

“…1. Phase diagram of the CaO-Al 2 O 3 -SiO 2 (CAS) system (after Osborn and Muan, 1960;Gentile and Foster, 1963;Ehlers, 1972). The investigation deals with compositions in the anorthite-wollastonite-gehlenite (An-Wo-Ge) compatibility triangle.…”