Thermal diffusivity measurements by photothermal and thermographic techniques

In this work, resulting from a collaboration between two laboratories, an analysis of different techniques to measure thermal diffusivity is presented. First, a brief description of the laser flash method, thermal wave interferometry photothermal techniques, and four different thermographic techniques in terms of experimental setups and in data processing algorithms is given. After that, results obtained on samples cut from the same block of stainless steel AISI 304 are reported. Uncertainty evaluations of the measurements are reported together with a discussion on the pros and cons of the related techniques. The agreement between the results obtained by applying the six techniques appears satisfactory from a practical point of view.