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This study deals with the evaluation of glass-forming ability (GFA) of oxides and is a critical reading of Sun and Rawson thermodynamic approach to quantify this aptitude. Both approaches are adequate but ambiguous regarding the behaviour of some oxides (tendency to amorphization or crystallization). Indeed, ZrO 2 and Al 2 O 3 were inappropriately listed by Sun and Rawson to be glassformer oxides while being intermediate ones. We present a non-dimensional approach to value GFA of single oxide by affecting to each one of the coefficients (without measuring units). Obeying to the non-dimensional analysis rules, we introduce a neglected (in all prior thermodynamic models) characteristic: the isobaric heat capacity (C p) of oxides, and execute a mathematical treatment of oxides thermodynamic data. We note this coefficient as thermodynamical relative glass-forming ability (ThRGFA) and formulate a model to compute it. Computed values of 2nd, 3rd, 4th and 5th period metal oxides reveal a clear differentiation between them. Indeed, all glass former oxides are characterized by ThRGFA values over 1•709. Moreover, the value intervals confirm the oxides classification into three groups (forming, intermediate and modifier) and sorting of the former ones in distinctive strong and fragile oxides.

The optimization of the formulation (nature and content of chemical components) and the technical parameters of the shaping-up process of ceramic insulators (in replacement of those in glass) are the objectives of this study. The decontamination of SiO2 (solid-liquid extraction of Fe xOy) and the increase of both BaO and ZrO2 amounts (while Na2O is partially eliminated) and the firing temperature allowed a significant increase of all the phys-mechanical and insulating properties at the commercial frequency 50-60 Hz. Samples with 15 mm diameter and 2 mm thickness and others for mechanical properties were needed. The characterization concerned Ba-Zr(Al xSi1-x)O3 ceramic samples. By data computing of the test results, a new "computed" formulation (Ba-stabilized and Zr doped mullite) showed excellent phys-mechanical (density, viscosity, flexural and traction strengths) and insulating properties (transversal resistivity, dielectric strength).