A Modified Glass Formation Criterion for Various Glass Forming Liquids with Higher Reliability

A modified indicator of the glass forming ability (GFA) from the previous γ = T_x/(T_l+T_g) for various glass forming liquids is proposed based on a conceptual approach which combines more acceptable physical metallurgy views in terms of the time-temperature- transformation diagrams. It is found that the glass forming ability for glass forming liquids is closely associated mainly with two factors, i.e. (2T_x-T_g) and T_l (wherein T_x is the onset crystallization temperature, T_g the glass transition temperature, and T_l the liquidus temperature), and could be predicated by a unified parameter γ_m defined as (2T_x-T_g)/T_l. This approach is confirmed and validated by experimental data in various glass forming systems including oxide glasses, cryoprotectants and metallic glasses, which all shows a higher reliability when their glass forming ability is predicted by the modified parameter.