Effect of Ga2O3 on structure and properties of calcium aluminate glasses

The effect of Ga2O3 on the structure and properties of calcium aluminate glasses fabricated by vacuum melting process was investigated by Raman spectrum, differential scanning calorimeter (DSC), and infrared spectrum methods. The results show that calcium aluminate glass network only consists of [AlO4] tetrahedral units. With the gradual addition of Ga2O3, the quantity of [GaO4] tetrahedral units increases. Substitution of Ga2O3 for Al2O3 results in a decrease in TgTx, and Tp, and an increase in the thermal stable index ΔT. Similarly, the absorption band around 3.0 μm obviously reduces and the transparency in 4.0-6.0 μm rapidly increases with increasing Ga2O3 content. However, the chemical stability of calcium aluminate glasses decreases if Ga2O3 is introduced due to the increasing of [GaO4] units in the glass network.