DIFFERENTIAL SCANNING CALORIMETRY
[DIN 510, ASTM E537-02]
The sample is heated with a constant heating rate under a controlled atmosphere, in most cases in a closed crucible (see test conditions).
The heat flow to the sample is recorded and compared to the heat flow to an inert reference substance heated in parallel.
During exothermic processes in the sample, the heat flow to the sample will be smaller, for endothermic processes higher than the heat flow to the reference.
Both endo- and exothermic signals are evaluated and the temperature range, peak temperature, peak signal and specific energy of each thermal signal are determined and calculated respectively.
In general, the maximum permissible temperature for thermal processes (reactions, distillations, drying operations) is approx. 100 °C below the onset of the first exothermic signal.
This is a conservative estimate and more detailed investigations often show that higher temperatures are still safe.