A 3D computer model of the CaO-MgO-Al2O3 T-x-y diagram at temperatures above 1300 °C

The research analyses the controversies surrounding technique for formation of a CaO-Al2O3 binary system and nature melting compounds in it, i.e. whether 12:7 compound is technically possible 1:1 1:2 are congruently or incongruently compounds. It also discusses CaO-MgO-Al2O3 ternary following can be formed: 3:1:1 alone or, addition to two more 1:2:8 2:2:14. A 3D model T-x-y diagram was created most common version, with six three Its high-temperature portion (above 1300°C) consisted 234 surfaces 85 phase regions. Ternary were formed as result peritectic reactions. Besides them, quasi-peritectic eutecticinvariant reactions occurred participation melt. principle construction threedimensional involved gradual transition from reaction scheme (which transformed into uni- invariant states) presented tabulated then graphical form (a template ruled isothermal planes corresponding reactions) prototype (graphic images all liquidus, solidus, solvus surfaces). design concluded transformation real after input base points coordinates (concentrations temperatures) adjustment curvatures lines andsurfaces. finished provides wide range possibilities visualisation diagram, including any arbitrarily assigned sections isopleths. designed help author’s software PD Designer (Phase Diagram Designer). To assess quality model, versions an section at 1840 °C compared: fragment experimental near Al2O3.