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A comparison of a novel single-pan calorimeter with a conventional heat-flux differential scanning calorimeter
Hongbiao Dong, John Hunt

There are a number of problems associated with a conventional heat-flux differential scanning calorimeter. When latent heat is absorbed or evolved, large temperature differences arise in the calorimeter and heat can flow between the reference and sample leading to rate sensitive enthalpy changes. In addition the heat appears to be smeared over a large range of temperatures. The reason for the smearing is discussed and a simple scanning calorimeter has been designed which eliminates the need for de-smearing. The present apparatus uses samples of about 1 cm3 and can be used from about 300 to 1300 °C. The temperature can be scanned at a constant rate or alternatively the heat flux can be fixed and the thermal response recorded. A heat flow analysis is presented which allows enthalpy changes to be calculated. The results for pure aluminium and an aluminium alloy (LM25) are reported.

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