Browsing by Author "Mazhdrakova A."
Now showing 1 - 1 of 1
Results Per Page
Sort Options
Item Crystallization behaviour of the systems Na2O/BaO/TiO2/SiO2/B2O3/Al2O3 and Na2O/BaO/TiO2/SiO2/B2O3/Fe2O3/Al2O3(2015-01-01) Harizanova R.; Mazhdrakova A.; Vladislavova L.; Avdeev G.; Bocker C.; Gugov I.; Rüssel C.This work reports data on the synthesis of glasses in three selected compositions of each of the systems Na2O/BaO/ TiO2/SiO2/B2O3/Al2O3 and Na2O/BaO/TiO2/SiO2/B2O3/Fe2O3/Al2O3 and the preparation of glass-ceramics by applying appropriate time-temperature regimes. Crystallization of a large volume fraction of cubic BaTiO3 is observed in both systems. The phase compositions of the obtained annealed specimens are investigated by x-ray diffraction, while the microstructure of the obtained glass-ceramics is studied by optical and scanning electron microscopy. The barium titanate crystals in the samples containing iron have a size varying from ca 100 nm to some hundreds of nm. They form interconnected structures which tend to grow further for all temperature-time schedules applied. The microstructure of the annealed samples containing no iron, as proved by optical and electron scanning microscopy, is characterized by barium titanate crystals of a size of some micrometers which are uniformly dispersed in the amorphous matrix. They start to grow independently and tend to merge upon longer annealing times.