Orientation Dependence of the Thermal Expansion Coefficients of Iron Borate FeBo3 Crystals.

We present high-resolution X-ray diffraction measurements of the lattice parameters of iron borate FeBO₃. These measurements were performed at room temperature and at various temperatures ranging from 400 up to 600°C, enabling the determination of the coefficients of thermal expansion (CTE). The three-dimensional (3D) indicatory surface of thermal expansion of FeBO₃was constructed in MathCad. It is shown that the orientation dependence of CTE in FeBO₃ is spheroid elongated on threefold axis [ABSTRACT FROM AUTHOR]