Thermal conductivity between the flash laser and the thermic method

Abstract

The flash laser method was proposed by Parker Butler in 1961. It is the most popular method for measuring the thermal diffusivity of solids or Thermal conductivity. The thermal conductivity (λ) is a characteristic of each material. It is expressed in W/mK and it is only valid for homogeneous materials. There are several methods for measuring this coefficient. The ratio between a temperature difference and the resulting thermal flux density, i.e., thermal resistance, can be determined in any case correctly, irrespective of the mechanism of heat transfer through it. The best measurement accuracies (better than 1%) are obtained by the method of the hot plate kept. In the simpler case where the heat transfer is reduced to a single mode, that of conduction (steady state). The λ of the test piece can be calculated if its geometry and temperature differences are known. In this work we will quote and compare the Flash Laser method and the thermal method.