PROPERTIES OF HEAVY-METAL OXIDE GLASSES

the effects of additions of SiO2, GeO2, B2O3, or Bi2O3 on the formation and properties of heavy metal oxide glasses based on the binary system PbO-Ga2O3 have been studied. Additions of bismuth oxide have little effect on the properties of these glasses, while additions of the other glass-forming oxides decrease the density and refractive index of the resultant glasses. Additions of silica and germania increase the glass transformation temperature, while additions of boric oxide and bismuth oxide slightly decrease this temperature. Silica and boric oxide seriously degrade the infrared transmission of these glasses, while additions of germania and bismuth oxide have only a small effect on the infrared cutoff frequency. The effect of the various glass-forming oxides on the properties of these glasses are discussed in terms of their possible structural roles in the amorphous network.