THE CALORIC CALIBRATION OF SCANNING CALORIMETERS

The present recommendation of the GEFTA working group ''Calibration of Scanning Calorimeters'' allows a precise heat and heat flow rate cali bration of scanning calorimeters, largely independent of instrumental, sample-related and experimental parameters. Electric energy, electric power, heats of transition and heat capacities of suitable calibratio n substances are used for calibration. The measuring method, measuring and evaluation procedure, calibration materials, significant influenc ing factors, sources of error and detailed examples are presented for these calibration methods. Besides specific problems of heat measureme nt (interpolation of the baseline for the peak area determination) and heat capacity measurement (interpolation between initial and final is otherms, determination of the true heating rate of the sample, thermal lag of the sample), general aspects (thermodynamic fundamentals, diff erence between heat and heat flow rate calibration factor, weighing pr ocedure) are also discussed.