M. Godickemeier et al., EFFECT OF INTERGRANULAR GLASS-FILMS ON THE ELECTRICAL-CONDUCTIVITY OF3Y-TZP, Journal of materials research, 9(5), 1994, pp. 1228-1240
The electrical conductivity of 3Y-TZP ceramics containing SiO2 and Al2
O3 has been investigated by complex impedance spectroscopy between 500
and 1270 K. At low temperatures, the total electrical conductivity is
suppressed by the grain boundary glass films. The equilibrium thickne
ss of intergranular films is 1-2 nm, as derived using the ''brick-laye
r'' model and measured by HRTEM. A change in the slope of the conducti
vity Arrhenius plots occurs at the characteristic temperature T(b) at
which the macroscopic grain boundary resistivity has the same value as
the resistivity of the grains. The temperature dependence of the cond
uctivity is discussed in terms of a series combination of RC elements.