Evaluation of Morphology-Stable Critical Size of KNbO3 Crystals
Evaluation of Morphology—Stable Critical Size of KNbO3 Crystals

Skeletal form of KNbO3 crystals growing in Li2B4O7 solvent was in-situ observed at 900C and it was found thatshallow depression started to develop on the surface of KNbO3 crystals when the crystal size exceeded several micron,typically 7 micron. Based on the quantitative criterion derived by Chernov, the estimated critical size of KNbO3crystals was 1 micron, which was consistent with the experimental measurement. The kinetic coefficients, kc erand kc,, in the criterion were experimentally obtained in the diffusive-convective and diffusive-advective flow statesrespectively.