LFA / Laser Flash Analysis for thermal diffusivity measurements

The heat transfer process is very important in many scientific and industrial areas and, thus, researchers and engineers are looking for a reliable technique for the thermal characterization of the materials used. The Flash method is a fast, non-destructive, non-contact, and absolute method for determining two fundamental thermal properties: diffusivity and conductivity.

The thermal diffusivity a is directly measured from the heat transmission through the sample under study. The front surface of a plane-parallel sample is heated by a light pulse shot and the resulting temperature evolution of the rear face is measured with an infrared detector. By using a reference specimen the specific heat, Cp, of solid samples may also be calculated. Combining these properties with the density value, ρ, the thermal conductivity, , is evaluated as follows: λ(T) = a(T) · Cp(T) · ρ(T)