X-ray powder diffraction study of leucite crystallisation

X-ray powder diffraction analysis was used to study leucite (KAlSi2O6) Crystallisation from amorphous precursors prepared by hydrothermal synthesis. Crystallisation of leucite was monitored at 800 degrees C, 900 degrees C and 1000 degrees C. At these high temperatures the stable form of leucite is a cubic one (high leucite), and a displacement phase transformation to tetragonal form (low leucite) takes place as it cools. The process of leucite transformation was studied using X-ray powder diffractometer D8 equipped with MRI high temperature chamber. It was detected that the transition from high temperature phase into the low leucite occurs below 550 degrees C.