Low-temperature fabrication of fluoride-free muscovite mica glass-ceramics with tunable boromuscovite and boromullite microstructures induced by BaO–TiO2 incorporation

A novel fluoride-free, high-alumina muscovite mica glass-ceramic system is presented, capable of highly energy-efficient low-temperature sintering (750–850 °C). BaO and TiO 2 were incorporated into K 2 O–SiO 2 –Al 2 O 3 –B 2 O 3 (KSAB) glass system by adding BaTiO 3 at 0, 5, and 10 wt%, which fully decomposed during melting at 1550°C. Unlike conventional flux-assisted sintering, the combined presence of BaO and TiO 2 acts as both a network modifier and crystallization mediator in the. This novel BaTiO 3 -assisted approach provides superior microstructural control, promoting the formation of a desirable interlocking network of needle-like boromuscovite and rod-like boromullite crystals at these low temperatures. X-ray diffraction and scanning electron microscopy confirm that the phase ratio and crystal morphology are significantly influenced by BaTiO 3 concentration. This tailored interlocking microstructure results in enhanced mechanical performance, with the optimal 5wt% BaTiO 3 -doped sample achieving an indentation fracture toughness ( K IC ) of ∼ 2.2 and a Vickers hardness ( HV ) of ∼ 3.9 GPa. These results position this BaTiO 3 -doped system as a strong, non-toxic, and energy-saving candidate for multifunctional applications across the electronic and biomedical fields.