EFFECT OF TITANIA ADDITION ON THE CRYSTALLIZATION CHARACTERISTICS OF GLASS-CERAMICS MATERIAL
The effect of 8wt% TiO2 incorporation on the microstructure of glass-ceramics prepared using two-step heat treatment temperatures at 356/656 has been carried out. The crystallization behaviour was investigated using X-ray diffraction (XRD) and field emission scanning microscopy (FESEM). The crystalline phases were precipitated and identified as wollastonite, andradite, monticellite and titanate dispersed in the matrix of residual glassy phase. The microstructure is characterized by dense, needle, circular, ellipsoidal, flake and lamellar twinning-like crystals dispersed in the amorphous phase. Also, fewer micro sized pores were detected between grains. The glass-ceramics showed excellent resistance to acid and alkali attack due to the presence of crystalline phases that were dispersed in the matrix of residual glassy phase. The glass-ceramics heat treated for 4 hours duration showed excellent density as well as excellent chemical durability in both acidic and alkali media.