Testing extremely small samples using the flash diffusivity method
International Journal of Numerical Methods for Heat & Fluid Flow
ISSN: 0961-5539
Article publication date: 6 March 2017
Abstract
Purpose
The purpose of the present research is to examine very small-sized samples of approximately 2-mm diameters. For samples of this size, the holder must make contact with the entire perimeter surface of the sample, and the sample is held in place by friction. This necessitates a mathematical model for the direct solution which accommodates the holder and a contact resistance between the holder and the sample.
Design/methodology/approach
Most flash diffusivity testing is performed on samples which are nominally 12-13 mm in diameter and are held by only a small contact area around the perimeter of the sample in a holder. With an experiment set up in this way, the effects of conduction between the sample and the holder are normally ignored.
Findings
This research examines the effects of the holder and the contact resistance on the measured thermal diffusivity of the sample and includes experimental results from laboratory measurements.
Originality/value
This work provides a method for finding thermal diffusivity for extremely small samples. This capability is important in cases involving precious materials or highly toxic materials where only small samples are available.
Keywords
Acknowledgements
This research was made possible by a grant from the Virginia Military Institute Jackson Hope Foundation. The assistance of Joseph Blandino in working with the thermal camera is also appreciated, as well as the National Science Foundation Equipment Fund for making the purchase of the thermal imager possible. The assistance of Ralph Dinwiddie and Jonathan Grimm at the Oak Ridge National Laboratory for some of the preliminary development of this method is also acknowledged.
Citation
McMasters, R., Harth, Z.J., Taylor, R.P. and Brooke, G.M. (2017), "Testing extremely small samples using the flash diffusivity method", International Journal of Numerical Methods for Heat & Fluid Flow, Vol. 27 No. 3, pp. 551-560. https://doi.org/10.1108/HFF-03-2016-0094
Publisher
:Emerald Publishing Limited
Copyright © 2017, Emerald Publishing Limited