DEVITRIFICATION AND VITRIFICATION OF TELLURITE GLASSES

The crystallization of pure tellurite glass during various heating rat es was studied. The activation energy for crystallization was 115 x 10 (22) eV mol-1. The glass transformation, T(g), starting crystallizatio n, T(x), crystallization, T(c) and melting temperatures, T(m), have be en reported for binary tellurite glasses of the form (1-x) TeO2-xA(n)O (m) [A(n)O(m) = MnO2, Co3O4 and MoO3]. Among many different parameters of the glass forming potential the ''two-thirds rule'', T(g)/T(m), th e glass stabilization range, DELTAT = T(x) - T(g), and the glass formi ng tendency, K(g) = (T(c) - T(g)) / (T(m) - T(c)), are reported for th e first time for tellurite glasses.