Study of Leucite-type Glass-ceramics by Thermally Stimulated Depolarization Current

Two different ingots of leucite-type glass-ceramics were studied by integral and by partial thermally stimulated depolarization current (TSDC) in the range from 173 to 370 K. Partial measurements showed distributed dipolar relaxation (P1) with a maximum at 256 K, caused by the interaction between alkali ions and nonbridging oxygen atoms. The following relaxation, observed at a higher temperature (P2), was attributed to the decay of the space charge dipoles. Only the beginning of P2 was studied because the development of the process was overlapped by the conductivity current. Addition of different oxides to the original material decreased the P1 and increased the P2 relaxation, due to the increase of the interface area