Structural evolution and phase separation of CaO · Al2O3 · SiO2 glasses in an electric field

In the present paper, the process of phase separation in calcium aluminosilicate glasses (CAS glasses) containing TiO2 as a nucleating agent is studied. A static electric field promotes the process of phase separation even when the time of heat treatment is short. The effect of electric field on phase separation acts through the higher polarizability of Ti ions. Alkali ions, when present, will diffuse toward the cathode, which may generate different micromorphology at the parts of samples near the cathode and the anode. X-ray photoelectron spectroscopy and Raman spectra analysis confirm the conclusion that the electric field has promoted phase separation in CAS glasses.