Combinatorial approach to new glasses

An 18-sample glass-melting furnace was newly developed and glass-forming compositional regions were found in lead-free B 2 O 3 -TeO 2 -[xBaF 2 /(100-x)BaO] ternary systems. The softening temperatures were measured in the systems to screen out low-melting compositions. The softening temperature ranges from 450 to 470 °C and the thermal expansion coefficient ranges (115-140)x 10 -7 °C -1 . These values were comparable to those of typical lead-containing glasses. It was also found that substitution of BaF 2 for BaO effectively lowers the melting temperatures without changing the thermal expansion coefficient.