Magnesium aluminate spinel (MAS) glass-ceramics composite has excellent mechanical and optical properties. It can be obtained from porous ceramic by infiltrating the proper choice of glass. In this study, porous MAS ceramic was prepared by conventional sintering from MAS powder to reach a bulk density of 2.48 g∙cm-3 (70.1% of relative density). The porous MAS ceramic was then infiltrated with molten lithium tetraborate glass (Li2B4O7; LTB) at 950℃ for 30 (IF30) and 60 (IF60) min. They were left to cool down to 700℃ inside the furnace before being taken out to quench in ambient. The glass-ceramics composite was obtained with 98.7% and 92.1% relative density for IF30 and IF60 cases, respectively. SEM images reveal a lower degree of porosity in the IF30 case, which achieves higher flexural strength of 119.7 MPa. X-ray diffraction and Raman spectroscopy indicate that Mg2B2O5 phase (at 2q =35°) and B2O5 functional group (at 847 cm-1) are formed during infiltration. Consequently, their micro vickers hardness increased (3.41®5.53®6.16 GPa).

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Soda lime glass (SLG) is one type of glass mainly used in beverage and food packaging industries. SLG has high potential as starting materials for glass-ceramics (GC) production as SLG consists of large proportion of silicate and has considerably low of melting temperature. In addition, large consumption of beverages and foods, SLG makes up a large bulk of the waste. Producing glass-ceramics (GC) from SLG is thus interesting. Processing of SLG to GC is strongly dependent on their thermal property. Before processing, thermal profile of SLG was analyzed by differential scanning calorimetry; crystallization temperature at 711 °C was identified at the heating rate of 5 °C/min. It was also possible to extract information about crystallization kinetic by applying the Kissinger and the Ozawa relations. It was found that crystallization activation energies were 365.06 and 381.60 kJ/mol, respectively. For the GC processing, SLG powder was mixed with precursors to the ratio of 60SLG-35SiO2-2TiO2-2ZnO-1CuO before sintering with single step method at 711, 800, 850, 900, 950, 1,000 °C. An analysis by XRD has shown that there were two phases; beta-quartz and beta-cristobalite, in the sintered samples. Different sintering temperatures have yielded different proportion of alpha-to beta-phases. SEM/EDX has also revealed uneven distribution of different oxides in the produced glass-ceramics.