Phase Separation Inducing Controlled Crystallization of GeSe_2-Ga_2Se_3-CsI Glasses for Fabricating Infrared Transmitting Glass-Ceramics

摘要

Infrared transmitting glass-ceramics based on the selected glass of 65GeSe_2-25Ga_2Se_3-10CsI were obtained by a two-stage heat-treatment method. Results of X-ray diffraction and scanning electronic microscopy indicated that droplet-like nanopar-ticles containing cubic Ga_(2-δ)Ge_δSe_3 crystals are homogeneously generated in the glass-ceramics and that the whole -glass-ceramic process is composed of phase separation, nucleation, and crystal growth. Evolutions of the optical and mechanical properties of glass-ceramics versus annealing time at the first-stage heat treatment were also investigated. Compared with the parent glass, the fabricated glass-ceramics show considerably enhanced fracture toughness, practicable infrared transparence, and microhardness, which confer them with considerable competitive advantages over currently used infrared materials.