doiSerbia

Augite-anorthite glass-ceramics from residues of basalt quarry and ceramic wastes

Khater Gamal A. (National Research Centre, Glass Research Department, Dokki, Cairo, Egypt)
Abu Safiah Mamduh O. (Saudi Geological Survey, Saudi Arabia)
Hamzawy Esmat M.A. (National Research Centre, Glass Research Department, Dokki, Cairo, Egypt)

Dark brown glasses were prepared from residues of basalt quarries and wastes of ceramic factories. Addition of CaF2, Cr2O3 and their mixture CaF2-Cr2O3 were used as nucleation catalysts. Generally, structures with augite and anorthite as major phases and small amount of magnetite and olivine phases were developed through the crystallization process. In the samples heat treated at 900°C the dominant phase is augite, whereas the content of anorthite usually overcomes the augite at higher temperature (1100°C). Fine to medium homogenous microstructures were detected in the prepared glass-ceramic samples. The coefficient of thermal expansion and microhardnessmeasurements of the glass-ceramic samples were from 6.16×10-6 to 8.96×10-6°C-1 (in the 20-500°C) and 5.58 to 7.16GP, respectively.

Keywords: crystallization, anorthite, augite, glass-ceramics, basalt, ceramic waste