Glass-ceramics, in recent years, have become the object of numerous studies following the increased scientific interest in the possibility of predicting microstructures and the chemical-physical characteristics through a precise choice of the composition and by specific thermal treatments. Our research group has been working on the preparation of glass-ceramics and the applications for the ceramic industry of material with innovative properties.

Glass ceramics are homogeneous vitreous systems which are subjected to an appropriate heating cycle that leads to a microstructure with specific chemical-morphological characteristics. The production of a glass ceramic material involves two different stages. The choice of the chemical composition of the parent glass and of the systems that promotes the crystallization (the so-called nucleants), permits the formation of the right crystalline phases, while the regulation of the process parameters (firing temperature, time, pressing and so on …) determines the microstructure of the material that is the crystals shape, their dimensional distribution, their spatial arrangement in the residual vitreous matrix and the final physical-chemical characteristics of the material.

Innovative ceramic materials can be obtained either through the sintering of glass ceramic powders or using the glass-ceramic as component in mixtures for tiles, such as the glass ceramic stoneware.

Some of these glass-ceramic systems are already industrialized by Gruppo Colorobbia

Monolithic systems make another promising class of materials, where crystallization of bulk is made in previously formed glasses. Besides the know-how of the crystallization process it is necessary to study the cooling and annealing cycle of the glass in order to avoid mechanical stresses and uncontrolled phenomenon of crystalline growth during the forming process.

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