Dr. Longgong Xia, Prof. Zhihong Liu b, Prof. Pekka Taskinen
The smelting of Zn-bearing materials will produce high ZnO content slags, and the monitoring of
slag properties has significant importance for the smelter. Phase diagrams can provide road maps in
optimizing metallurgical processing parameters. The determination of phase diagrams in multicomponent
oxide systems needs sufficient experimental data. However, thermodynamic information
of ZnO rich slags is incomplete in the literature. Therefore, systematic work has been performed
to determine the phase relationships in the Cu-O-ZnO, Cu-O-SiO2, ZnO-SiO2, and Cu-OZnO-
SiO2 systems in previous studies. Both liquidus temperatures and the solid solubility data have
been collected.
The equilibration/quenching/EDS technique has been applied in determining the eutectic point of
the Cu-O-ZnO-SiO2 system. The technique used in this study involved preparation of a synthetic
pellet of predetermined composition. The pellet placed in a suitable container was then equilibrated
at the target temperature for certain period of time, followed by rapid quenching, so that the phase
assemblages at high temperatures were frozen instantly. The compositions of all phases in equilibrium
were measured by EDS from the polished sections.
All the results from the present study and previous studies have been used in constructing the 3D
version of ternary phase diagrams of the Cu2Ox-ZnO-SiO2 system. The results of the present study
will provide novel information and both for fundamental scientific research and industrial practices.