Thermal stability of boroaluminosilicate glass with rare earth doping

The glass-forming range of rare earth oxide and BaO co-doped Al₂O₃- B₂O₃-SiO₂ system was explored, and the effect of the rare earth oxide content on glass-forming region was examined firstly. Then the effect of the rare earth oxides content on the glass thermo-stability was analyzed through differential thermal analysis technique. Finally, the glass after heat-treatment near T_x(the temperature at the beginning of exothermic peak formation) formation temperature was analyzed using XRD and TEM / EDS analyses. The results showed that the region of glass-forming range expanded firstly, and then shrank when the rare earth content increased gradually. The glass lacking of transparence after heat treatment near T_x was due to the phase separation, and the rare earth ions mainly distributed in the boron-aluminum rich phase, the higher the glass heat-treatment temperature, the more seriously the glass phase separation which occurred. When the glass was heat-treated at a high temperature of 900 °C, the diffraction peaks of crystal were very obvious in the XRD spectrum. Through comparing and analyzing, the main crystalline phase might be determined as SmAl_2.07(B₄O₁₀)O_0.6 with the same structure as NdAl_2.07(B₄O₁₀)O_0.6.