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 (P-1) 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 (P-2), was attributed to the decay of the space charge dipoles. Only the beginning of P-2 was studied because the development of the process was overlapped by the conductivity current. Addition of different oxides to the original material decreased the P-1 and increased the P-2 relaxation, due to the increase of the interface area