Temperature, heat and heat flow rate calibration of scanning calorimeters in the cooling mode

The current publication continues the series of recommendations of the ‘Calibration’ Working Group of the German Society for Thermal Analysis (GEFTA) for temperature, heat and heat flow rate calibration of scanning calorimeters. It deals with calibration in the cooling mode. The procedures to be applied are essentially identical to those applied in the heating mode. Due to the general occurrence of supercooling for first-order phase transitions during cooling, liquid crystals and substances with higher-order phase transitions are recommended for temperature calibration. Substances with weak supercooling or substances for which the temperature dependence of the transformation enthalpy is known are recommended for heat calibration. The thermodynamic fundamentals relevant to the temperature dependence of phase transition enthalpies and phase transition temperatures are discussed. Detailed examples make it easy to follow the recommendations.