Investigation of phase transition in Li2TiO3 by high temperature X-ray diffraction

Li2TiO3, one of the promising candidates for tritium breeding in a thermonuclear fusion reactor, has been investigated by X-ray diffraction at high temperatures. It was found that the crystal system of Li2TiO3 is monoclinic at 30–900 °C with a higher order structural phase transition at about 450 °C, showing agreement with dependence of thermal conductivity on temperature. This phase transition involved variation of the thermal expansion coefficient, which could also be observed by dilatometry.