In the Y2O3-AI2O3-B2O3 system, homogeneous glasses were obtained from compositions containing from 50 to 65 mol% B203. The density, refractive index, and thermal expansion increase as Y 2 0 3 replaces either B2O3 or AI203. These glasses have a dilatometric softening temperature above W C , and below 300°C their dc electrical resistivity exceeds that of fused silica. The infrared absorption spectra indicate that B03, B04, and AIO, groups are present in these glasses.[

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ChemInform Abstract The refractive index, density, microhardness, chemical durability, thermal expansion, and dc electrical resistivity are measured for nine glasses in the Y2O3-Al2O3-B2O3 (YAB) system containing 50-65 mol% B2O3. The density, refractive index, and thermal expansion increase as Y2O3 replaces either B2O3 or Al2O3. The YAB glasses have a dilatometric softening temp. above 665 rc C, and below 300 rc C their dc electrical resistivity exceeds that of fused silica. The IR spectra show the presence of BO3, BO4 and lO4 groups in these glasses.

No abstract