The crystallization behavior of Dy3Â +/Tb3Â + doped aluminoborosilicate glasses

The crystallization behavior and microstructure of a series of Dy3 +/Tb3 + doped aluminoborosilicate (ABS) magneto-optical glass was investigated using differential scanning calorimetry (DSC), X-ray diffraction (XRD), and scanning electron microscopy (SEM). The apparent crystallization activation energy (Eg) and the kinetic properties at the corresponding glass transition temperature (Tg) were studied as a function of Dy3 +/Tb3 + concentration. The results showed that the glass matrix precipitated Al3Tb(BO3)4 and TbBO3 crystals when subjected to heat treatment at 852.8 and 902.6 °C, respectively. The crystallization activation energy of these two crystalline phases (Al3Tb(BO3)4 and TbBO3) was Ep1 = 993.3 kJ/mol and Ep2 = 544.97 kJ/mol, respectively. The average crystallization index was 0.5 and 0.8, respectively. By applying the Kissinger equation to the parameterized crystallization behavior, the calculated phase transition activation energy was determined to be 420.18 kJ/mol. The parameterized crystallization behavior of this particular ABS magneto-optical glass can be used to avoid the deterioration of magneto-optical properties due to the crystallization of glass matrix.