Li2O (Lithium Oxide, Lithia)

Notas

Lithium oxide, commonly referred to as lithia (Li2O), is a highly reactive, low-molecular-weight alkali flux utilized in ceramic glazes. As the lightest member of the alkali group, it provides significant molar impact even at low weight percentages. Due to its small ionic radius and low charge, lithia is exceptionally mobile within a molten glass matrix, often diffusing into the clay body to form a unique interface layer. It acts as a powerful flux that effectively lowers glaze viscosity and maturing temperatures while simultaneously enhancing surface gloss and color depth. While it can produce intense coloration, particularly in low-alumina, high-alkali systems, its reactivity also promotes surface texture and devitrification. Lithia is often employed to lower the coefficient of thermal expansion, making it a valuable tool for improving thermal shock resistance, though its contribution to expansion is non-linear and difficult to predict accurately at levels exceeding 5 mol%. High concentrations of lithia may induce crystallization, such as the formation of spodumene during cooling, which can lead to expansion stresses. While it serves as an effective flux when paired with boron or sodium at low temperatures, it can cause bubble defects if used without other supporting alkalis and may increase lead solubility in relevant glaze formulations.