The axial expansions of BeO between room temperature and 1700°C

Abstract

The temperature dependencies of the lattice constants of BeO have been determined to provide the necessary intermediate data for assigning sample temperatures to high-temperature X-ray powder diffraction experiments. An accuracy of 10 °C at temperatures up to at least 1700 °C can be attained if precise diffraction measurements are made. The lattice-constant values, used to precalculate diffraction maxima locations at various temperatures, are given by a~ 2 = at ~ + Aat 2 +_ Xa and ct~ = ctl + Act 2 q-Xc where tl is the room temperature, t2 is the test temperature, Aatg. and Act2 are defined by