The investigated sample was a thin rolled steel foil with a thickness of 25 µm. Steel foil can for example be used for distance compensation in the adjustment of machines or in the production of magnet systems.
The extremely thin sample and the resulting extremely short measuring time push the LFA using the conventional vertical measurement method (Through-Plane) to its limits. To be able to measure such thin samples a horizontal measurement method with the in-plane adapter can be used.
The measurement of the thin steel foil was performed from room temperature to 1200 °C. From room temperature to 900 °C the thermal diffusivity increases with temperature. A rapid increase of the thermal diffusivity can be seen between 900 °C and 1000 °C. Here, the sample starts to melt which results in a drastic thermal diffusivity change. Further increase in temperature leads to a decrease in thermal diffusivity.
