Simple and Inexpensive Flash Technique for Determining Thermal Diffusivity of Ceramics

A simple technique for determining the thermal diffusivity of ceramics at room temperature is presented. The technique is a variant of the well‐known flash technique, but uses an inexpensive photo flash as the energy source, a fast‐response paste‐on thermocouple, and a precision digital voltmeter to measure the temperature rise. A data analysis technique, which does not need any knowledge of either the initial or the maximum sample temperature, is presented. Good agreement with the laser‐flash technique for ceramics with thermal diffusivities in the range 0.5 × 10 −6 to 75 × 10 −6 m 2 · s −1 is obtained. Measurements of thermal diffusivity of stainless steel and graphite (standard reference materials) indicate that the method is accurate to within 3%.