Abstract: The effect of TiO₂ and Cr₂O₃ addition on crystallization of nickel slag glass-ceramics is studied by XRD, SEM and EDS methods. The result indicates that, when composite nucleating agent TiO₂ + Cr₂O₃ is added, nickel slag glass-ceramics will, after heat treatment, produce phase crystallization to form calcium-rich phase and silicon-rich phase, where spinel type crystal Mg₂TiO₄ is the first to precipitate, and the diffraction peak of common pyroxene crystal Ca(Mg, Al, Ti)₂O₆ also occurs. TiO₂ does not directly form crystal nucleus but promotes the formation of the spinel type crystal Mg₂TiO₄, facilitating the crystal growth.

Key words: Nickel slag, Glass-ceramics, Nucleating agent