The effects of MgF2 in four complex nucleating agents on the performance and crystallization of lithium aluminum silicate glasses

Glasses and glass-ceramics in the LAS system containing four complex nucleating agents (TiO ₂+ZrO ₂+P ₂O ₅+MgF ₂) were prepared by the traditional melt quenching technology and two-step (nucleation-crystallization) method. The effects of MgF ₂ contents on the performances and crystallization behavior of parent glass were examined using XRD, SEM, DSC, Fourier transform infrared, Transmittance, TEC, Density, Bending strength, Vickers hardness and the Quality loss of Alkali (Acid) resistance. The result reveals that when the complex nucleating agents (TiO ₂+ZrO ₂+P ₂O ₅+MgF ₂) in a ratio of 2: 2: 5: 3, the parent glass has the most prominent performance and optimal crystallization promotion. Fluoride has the better promotion effect on the formation of ZrTiO ₄ when the MgF ₂ content is 2 wt%, regardless of whether β-quartz or β-spodumene solid solution used as main crystalline phase. Besides, fluoride may be hinder the precipitation of AlPO ₄ (in β-quartz solid solution) and has the limit impact on the formation of AlPO ₄ (in β-spodumene).