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Lead-containing glasses have been used from the ancient time. Recently, due to the possible application in optics, electronics, nuclear techniques, wastes inactivation. the interest in these types of glasses has been renewed. For lead waste inactivation, glasses with high amount of PbO in the composition are required, those exhibiting at the same time a high chemical and thermal stability. Thermal behavior of lead-silicate glasses was examined by differential thermal analysis (DTA). Infrared spectroscopy was used to investigate the structure of the glasses. The spectra were interpreted in terms of the structures of silicate group by comparison with the spectra of other silicate crystals. The DTA and infrared data were correlated with the chemical stability tests

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Vitroceramic coatings from the oxide system SiO2–CaO–Na2O–B2O3-TiO2 were obtained on metallic supports (titanium and austenitic steels with high Cr and Ni contents). The coating technology was classical enamelling. The metallic support is coated by either immersion or painting with a slurry layer resulting from a mixture of a frit (having the best oxide composition for each metallic support) with a liquid, fired at the enamelling temperature and then subjected to a thermal treatment for crystallisation. Good adherence between the two different materials is achieved when their thermal expansion coefficients are close to each other. The vitroceramic coating–metallic support system was characterised by optical microscopy, SEM, and X-ray diffraction. The adherence of the vitroceramic layer to the metallic supports was determined using microhardness tests carried out at the interface. Evidence of the processes occurring at the interface (gas bubbles, micropores, chemical binding, etc.) was also found. The coating layers are types of biocompatible and bioactive vitroceramic materials.