Microscale Combustion Calorimetry method according to ASTM D7309

Purpose of Microscale Combustion Calorimetry

The Microscale Combustion Calorimetry (MCC) method predicts flammability characteristics of materials using only milligram-size samples. The small required sample mass and a quick completion of the test makes Microscale Combustion Calorimetry an useful tool in materials development, particularly in screening a group of materials and selecting the most promising candidates for further testing in larger scale.

Microscale Combustion Calorimetry method

In the Microscale Combustion Calorimetry method a small amount of the tested material is subjected to a controlled heating rate inside the pyrolysis chamber of the device. The material may be tested either under an oxygen-free environment (usually in nitrogen) or in an oxidative atmosphere (MCC method A and method B, respectively). The sample mass is usually between 1 and 5 milligrams, and the usual heating rate is 1 °C/s. The sample is heated to a selected maximum temperature, however not higher than 900 °C. The tested material may take any form, such as fibre, powder or pellet, provided it fits inside the specimen cup 5 mm in internal diameter.

As the sample in the pyrolysis chamber is heated, the released gases are led into the combustor section of the device where they are mixed with excess oxygen. The pyrolysis gases are combusted therein, and the heat release is calculated with oxygen consumption calorimetry. Different flammability and material parameters, including heat release capacity, fire growth capacity, temperature of maximum heat release and specific heat release may be calculated from the heat release measurement.

Microscale Combustion Calorimetry test report

After the completion of measurements, the derived flammability and material parameters are presented in a report, and the measurement data files can be provided.