抄録
Growth mechanism of oxide crystals from a heterogeneous condition of solid-melt mixtures formed by incongruent melting has been analyzed using a newly developed in-situ observation system, which is composed of a time-resolving X-ray powder diffraction apparatus using a PSPC (Position Sensitive Proportional Counter) combined with an optical microscope, images of which are detected by a CCD sensor and stored into a video-recording system. Measurements are carried out on the oxide superconductor system Y-Ba-Cu-O, where well-habited single crystals of the superconductive compound YBa2Cu3Ox are easily obtained from a mixture of solid Y2BaCuO5 and liquid with the aid of the peritectic reaction. The results indicate that recrystallization by Ostwald ripening plays a main role in such a heterogeneous condition and diffusion of YBa2Cu3Ox molecules in the liquid phase determines the whole growth rate.
