Several properties of alkali-alkaline earth metaphosphate glasses have been
measured. These properties include density, transformation range viscosity
and de electrical conductivity, with emphasis on the conductivity measurem
ents. Glasses studied include series in which Li2O or Na2O is replaced by M
gO, CaO or BaO, mixed alkali glasses containing a constant concentration of
BaO and a series in which ZnO replaces BaO. The conductivity decreases by
orders of magnitude as an alkaline earth oxide replaces either Na2O or Li2O
. Replacement of one alkaline earth by another while maintaining the identi
ty of the alkali ion has a much smaller effect on the conductivity of these
glasses. The mixed alkali effect is evident in the conductivities of the L
i-Na and Na-K glasses. (C) 2000 Elsevier Science B.V. All rights reserved.