1. Thermal studies of ZnO-BO-PO-TeO glasses.
- Author
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Mošner, P., Vosejpková, K., Koudelka, L., and Beneš, L.
- Subjects
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THERMAL analysis , *ZINC oxide , *METALLIC glasses , *TELLURIUM , *DIFFERENTIAL scanning calorimetry , *GLASS transition temperature , *CRYSTALLIZATION - Abstract
The effect of TeO additions on the thermal behaviour of zinc borophosphate glasses were studied in the compositional series (100 − x)[0.5ZnO-0.1BO-0.4PO]- xTeO by differential scanning calorimetry, thermodilatometry and heating microscopy thermal analysis. The addition of TeO to the starting borophosphate glass resulted in a linear increase of glass transition temperature and dilatometric softening temperature, whereas the thermal expansion coefficient decreased. Most of glasses crystallize under heating within the temperature range of 440-640 °C. The crystallization temperature steeply decreases with increasing TeO content. The lowest tendency towards crystallization was observed for the glasses containing 50 and 60 mol% TeO. X-ray diffraction analysis showed that major compounds formed by annealing of the glasses were ZnPO, BPO and α-TeO. Annealing of the powdered 50ZnO-10BO-40PO glass leads at first to the formation of an unknown crystalline phase, which is gradually transformed to ZnPO and BPO during subsequent heating. [ABSTRACT FROM AUTHOR]
- Published
- 2012
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