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.
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.
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.
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.
