Material CFRP
Mettler Toledo DSC 821e
Heated up to 160 Deg C
Cooled to 50 Deg C
Heated again to 250 Deg C
Equipment is equipped with a cooler as well.
NO2 used as purging gas
Non-calibrated machine possibly be a reason for that. Did you check if you are properly filling your Aluminium flask with material? That is because in prober filling can lead to deviant, inaccurate results
Hi Mr Mostafa. Thank you very much sir it was indeed helpful. Yes we did fill the crucible properly to maintain proper contact point. Other than that the only possible cause which i could think of is a non calibrated device.
Dear Mr Mostafa!
Below, some considerations:
a) An abrupt change of the heat transfer between the sample and the pan:
1) Samples of irregular form can topple over in the pan.
2) Polymer films that have not been pressed against the base of the pan first change shape (no longer lie flat) on initial warming. Afterward, on melting, they make good contact with the pan
b) An abrupt change of the heat transfer between the pan and the DSC sensor:
1) Distortion of a hermetically sealed Al pan due to the vapor pressure of the sample.
2) Slight shift of the Al pan during a dynamic temperature program due to different
coefficients of expansion.
etc
Hi Arun,
from your question it is not clear what value you are trying to measure in the DSC, and where did you get your "expectation" of the value from (datasheet, other experiment?). I say that because depending on what you want to measure on the DSC, the heating rates and sample mass can be adjusted for an optimal measurement.
Therefore to be able to compare your experiment with any expected values these factors also have to be accounted for. There are several nuances in a DSC experiment which can influence slightly the results. For more information please check Ehrenstein's "Thermal analysis of plastics".
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