Measurements of thermal diffusivity, specific heat capacity and thermal conductivity with LFA 447 apparatus

The LFA 447 can be successfully used for measurements of thermal diffusivity, specific heat and thermal conductivity of various samples. It is especially useful when determining the properties of materials on a very small scale. The matrix measurement mode allows for determining the local properties with a fine resolution, down to 1 millimeter.

Special attention needs to be taken when determining the specific heat capacity in the comparative method. First of all, the test and reference sample should be of nearly identical thickness. Secondly, their heat diffusion time should be comparable, so that the heat losses from both samples during the measurement are similar. Finally, the leveling of the samples is very important. Very small discrepancies can cause a massive error in the derivation of specific heat capacity and, as a result, thermal conductivity.