Investigation of the effects of TiO2 and ZrO2 nucleating additives on the crystallization behavior, mechanical and physical properties of MgO-Al2O3-SiO2-B2O3 glass-ceramics

In this study, the effects of TiO2 and ZrO2 nucleating additives on the crystallization behavior, mechanical and physical properties of MgO-Al2O3-SiO2-B2O3 glass-ceramics were studied. For this purpose, three different compositions were prepared as TiO2 added compound (MASB-T), ZrO2 added compound (MASB-Z) and both TiO2 and ZrO2 added compound (MASB-TZ). The prepared compositions were melted and poured into the graphite mold. Thus, glasses were obtained. Some of the glasses are powdered for DTA. Glass-ceramics were produced by crystallization of other parts at 800-900-1000-1100-1200°C temperatures at 5°C/min and 10°C/min heating rates with 1 hour and 3 hours waiting times. DTA and vickers hardness tests were applied to the glasses. Kinetic analysis, vickers hardness, wear, Archimedean density, XRD and SEM-EDS analyzes were applied to glass-ceramics. It was determined that the TiO2 additive increased the glass hardness more than the ZrO2 additive, facilitated the crystallization and turned the color of the glass yellow. While the dominant phase seen as a result of crystallization of TiO2 doped samples at high temperatures is "sapphirine", it is "spinel" in ZrO2 doped samples.