Thermal expansion and density of $80.5\%\mathrm{LiF}$–$19.5\%\mathrm{CaF}_2$ eutectic

The thermal expansion of the $80.5\%\mathrm{LiF}$–$19.5\%\mathrm{CaF}_2$ eutectic is measured in the temperature range from $300$ to $850$ K at an error of $1\%$. The measurement results are approximated by an equation whose coefficients were calculated by the least-squares method. The tabular data on the relative thermal expansion, as well as on the true and mean thermal expansion coefficients for the eutectic, are calculated in the temperature range from $300$ K to the melting point of $1042$ K. The eutectic density is determined by the method of hydrostatic weighing in distilled water. Based on the measurement results and thermal expansion data, the dependences of the eutectic density on temperature in the temperature range from $300$ to $1042$ K are calculated and presented in the form of tables. The error of calculation of the eutectic density is found to be equal to $0.039$–$0.194\%$ depending on temperature.