Ceramics-Silikáty 44, (2) 67 - 70 (2000)

Vaporisation from a multicomponent silicate melt was studied by determining the losses in weight over the temperature range of 1140 -1400 °C in the atmospheres of nitrogen, air and carbon dioxide respectively. The effect of water vapour on vaporisation from this melt was studied in the gases enriched with water vapour. It was found that the vaporisation losses increase with increasing partial pressure of water vapour and that the differences between vaporisation in the individual atmospheres gradually decrease with increasing partial pressure of water vapour. The vaporisation losses also increased with increasing rate of flow of the gases and particularly with increasing temperature. At the lowest temperature employed (1140 °C) the time dependence of vaporisation losses was approximately linear. However, the vaporisation rate at 1400 °C decreased in terms of time. Water vapour may to a certain extent influence the rates of partial processes taking part in vaporisation.