Improvement of specific heat measurement by the flash method

Abstract

A new method to improve the accuracy of the flash method for the measurement of specific heat and thermal conductivity has been proposed. A temperature rise versus time curve was replotted with non-dimensional time scaled with the time elapsed to reach the maximum temperature rise. And instead of comparing the measured temperature rise of the test sample with that of the standard material at a certain predetermined time, say, half time (t(1/2)) or maximum temperature (Delta T-max), the resealed temperature rise curve was integrated between 0.5t(1/2) and 1.5t(1/2) to increase the reproducibility and accuracy of the specific heat measurement. In order to minimize the error of the measurement a circular disc was used to cut off the excess flash energy input to the sample surface. It was found that the proposed method produces the measurement accuracy of the specific heat within 1.7% in comparison with the standard data. (C) 2006 Elsevier B.V. All rights reserved.