Phase Transition Traced By Conductivity Measurements: Quantitative Analysis

The measurement of the crystal growth velocity is carried out by analysing the change in the resistivity of the sample. The calculation of the crystal growth velocity is developed for crystal formation in the volume, crystal growth initiated at the electrodes as well as perpendicular to the electrodes, all in a cylindrical geometry. The electrical resistivity of a sample in the system BaAl2B2O7 was measured during cooling between liquidus temperature and transformation temperature using a fixed frequency of 3.7z. The melt crystallised in this temperature range during cooling starting from the electrodes. The change in conductivity as a function of the temperature was fitted with VFT-equation for both the melt and the crystalline phase.