|As an important advanced decoration material, glass-ceramics has attracted much
attention. By means of XRD, SEM and mechanical properties tests, this research
studied the sintering and crystallization behavior during the preparation of
CaO-MgO-Al2O3-SiO2 glass-ceramics. Results showed that with increase in MgO
content, crystallization temperature increased, linear sintering shrinkage (%)
decreased and porosity number increased, leading to a lower apparent density.
However, with increase in temperature and time, linear shrinkage (%) increased.
In addition, the increase of MgO made the vibration frequency of infrared spectrum
move to the low-frequency, showing transformation from wollastonite to pyroxene
phase. With increase in MgO content, particle size decreased, crystallization rate
increased, microhardness of glass-ceramic material increased and flexural
strength increased initially, then decreased. The flexural strength of glass-ceramics
with 10% MgO can be 103 MPa.
[Keywords: MgO, Glass-ceramics, Sintering, Crystallization]