Processing and characterization of transparent TeO2–Bi2O3–ZnO glass ceramics

Fabrication of TeO2–Bi2O3–ZnO glass ceramics with high transmittance in the near infrared (NIR) region is reported in the present work. Transparent tetragonal bipyramid crystals, tens of micrometers in size, with a refractive index closely matched to that of the glass matrix were formed using a two-step heat treatment. Nucleation- and growth-like curves for this crystal phase were determined using Differential Scanning Calorimetry (DSC). The crystalline phases present in the glass ceramics were identified via x-ray diffraction as a function of heat treatment. The lowest absorption coefficient of glass ceramic is approximately 0.5/cm in the near infrared region (1.2 to 2.8 μm).

► Glasses in the TeO2-Bi2O3-ZnO family were heat treated to form glass ceramics. ► The nucleation- and growth-like curves for the crystal phases were measured. ► Crystal fraction and phase as a function of heat treatment was examined. ► Optical and mechanical properties of the glass ceramics are presented.