The effect of heat treatment to a parent glass of the composition CaO-MgO-Al2O3-SiO2 (CMAS) on the course ofcrystallization and properties of the Bayan Obo east mine tailing glass-ceramics is examined. The crystallization behavior,phase composition, morphology and structure of glass-ceramics are characterized. The results indicate that the phases formedin the glass-ceramics are augite and the initial nucleation phases are magnetite, which can be proved by differential scanningcalorimetry (DSC), X-ray diffraction (XRD) and scanning transmission electron microscope (STEM). Heat treatment plays asignificant role in improving the crystallization process, fracture characteristics, modulus and bending strength. All of theseproperties reach a maximum for the fully crystallized glass-ceramic. Scanning electron microscope (SEM) and atomic forcemicroscope (AFM) are used to reveal the topography of the fracture surfaces. The intergranular fracture can be observed onthe fracture surface.
Keywords: Bayan Obo east mine tailing, Glass-ceramics, Heat treatment, Fracture surfaces, Fracture toughness