Rapid synthesis of Gd2Zr2O7 glass-ceramics using spark plasma sintering

Glass-ceramics are possible host matrix for high level waste immobilization. The Gd2Zr2O7 glass-ceramic matrix was successfully synthesized using spark plasma sintering (SPS) method in 5 minutes. The phase transition with sintering temperature was studied using X-ray diffraction, Raman and transmission electron microscopy. It revealed that samples kept a main defected fluorite phase as being sintered below 1800 degrees C. Glass phase increased rapidly beyond 1850 degrees C. The amorphous structure became the main body at 1900 degrees C, with nanoscale crystal scattered in the bulk. With the increase of glass phase, the grain boundary became almost indistinguishable. The relationship between the final phase of Gd2Zr2O7 with its synthetic temperature range and corresponding technology was reviewed. Gd2Zr2O7 glass-ceramics could be acquired by extending the sintering temperature beyond 1850 degrees C using SPS method.