Abstract

We present photoacoustic (PA) measurements on polished or oxidized steel samples, with or without a black paint layer. According to the one-dimensional (1D) heat flow model, the primary parameters of the PA signals are the thermal effusivity and the thermal resistance of the layer. 2D effects become relevant only below 1 Hz. The thermal conductivity and volume specific heat of the top layers could be determined after independent measurement of layer thicknesses.