The influence of the cooling rate of A 2PbO · SiO2 melt on the constitution of silicate anions

The kinetics of crystallization in a 2Pbo · SiO 2 melt have been investigated. A TTT-diagram was constructed, which describes the kinetic parameters for the formation of crystalline phases in the system. By means of silicate anion analysis the relationship between the cooling rates of the melt and the structure of silicate units in solid 2PbO · SiO 2 has been studied. Substantial differences in the thermal treatment of the melt lead to alterations of the silicate anion constitution, which cause changes in the crystallization behavior of glassy 2PbO · SiO 2 .