Question

For a Differential Scanning Calorimetry Experiment,

The samples are contained in aluminum pans with crimped-on covers. The instrument is stationary during operation, so samples placed in open pans would not spill. Why do you think the covers are needed?

Answer 1

DSC measurement requires that samples are enclosed in a sample pan in order to avoid the direct contact between sample and furnace and/or sensor, because if the samples come into contact with the furnace/sensor problems can occur on the baseline. Memory can be affected and damage to the furnace/sensor can occur (in the worst case the furnace/sensor can be destroyed).The standard aluminum sample pans and covers can be used for solids and powders that do not decompose or boil in the range of -170 ° to 600 °C. They should not be used over 600 °C, as that approaches the melting point of aluminum at 660 °C.If the temperature is above 600 °C, or if aluminum is reacting with the sample standard sample pans and covers in copper, gold, graphite, and alumina are used. The standard copper pans and covers can be crimped (using the same crimpers as standard aluminum pans), while in case of gold, graphite and alumina, the sample is placed inside the pan with the uncrimped cover on top of the sample. So the covers are needed in a DSC.