TEXTURED LI2O-CENTER-DOT-2SIO(2) GLASS-CERAMICS

Textured glass ceramics of Li2O . 2SiO(2) composition were prepared wi th a highly oriented microstructure. This orientation was achieved by surface crystallization and by volume crystallization moving the glass through a temperature gradient. The microstructure was determined by scanning electron microscopy. Quantitative texture investigations were performed by X-ray pole figure measurements, calculations of orientat ion distribution functions and inverse pole figures. The degree of ori entation was calculated for randomly oriented bulk material, surface-c rystallized material and material crystallized in the temperature grad ient. The (002) planes of the surface-crystallized and of the temperat ure-gradient-crystallized materials resulted in a strong fiber texture parallel to the surface of the sample with a texture intensity about 40 times that of random material in the normal direction.