Anisotropic glass-ceramics produced by extrusion through opposed dies

Crystallization, texture and second-harmonic generation in TiO2–BaO–B2O3 glasses

“…Various methods have been applied to glass-ceramics to obtain defined crystallographic orientation, e.g., solid-state epitaxy [12][13][14], glass extrusion [15][16][17] or temperature gradients [18].…”

Nucleation and crystallisation kinetics of a Na-fluorrichterite based glass by differential scanning calorimetry (DSC)

“…Richterite glass-ceramics have also been studied to examine the possibility of producing oriented glass-ceramics with different methods. Therefore, Ashbee [17] has extruded green glasses through opposed dies at temperatures near their respective crystallisation temperatures, and Keding et al [18] have reported on the use of electrochemical nucleation to induce orientation of the crystals.…”

Two-die assembly for the extrusion of glasses with dissimilar thermal properties for fibre optic preforms

“…Extrusion has been initially investigated for the extrusion of an alkali lime silicate glass and a calcium aluminate glass [12], and since then, gallium-lanthanum-sulphide glass [13], glass ceramic materials [14] and glass matrix composites [15] have also been extruded. It is especially applicable to glasses with a narrow working temperature range for shaping, either exhibiting a steep viscosity-temperature curve or a high tendency to crystallise.…”