Scope:

ASTM E794 – 06 is useful for quality control, specification acceptance, and research. The fusion and crystallization temperatures of crystalline materials can be determined quickly using differential scanning calorimetry and differential thermal analysis. 

Procedure

ASTM E794 – 06 entails heating a test specimen at a regulated rate through the fusion area in a controlled environment. The difference in heat flow (for DSC) or temperature (for DTA) between the test and reference materials as a result of energy changes is constantly monitored and recorded. The absorption of energy by the specimen marks a transition, resulting in an endothermic peak in the heating curve.

Specimen size

The mass of the specimen to be utilized is determined by the size of the transition enthalpy and the capsule volume. For comparing multiple results, use similar mass (65 %) and encapsulation. Weigh 1 to 15 mg of material to an accuracy of 0.01mg into a clean, dry specimen capsule.

Data

Tm = melting temperature

Tp = melting peak maximum,°C

Tf = return to baseline,°C