Microscopic thermal diffusivity measurements of ceramic and metallic foams lumps in temperature

• Development of an original method of measurement of the thermal conductivity using photoreflectance microscopy.
• Measurements performed directly on a very small homogeneous zone area of foam skeleton.
• Sample preparation allows accounting for brittleness and possible optical semi-transparency of the foam lumps.

This paper presents temperature dependent thermal diffusivity measurements of NiCrAl and mullite foam solid skeletons. The photoreflectance microscopy (PM) technique is used to characterize these skeletons at the microscopic scale. The characterized homogeneous zone area does not exceed 100 μm2. A singular sample preparation has been realized to take into account the brittleness and the optical semi-transparency of the mullite foam lumps. This specific sample preparation as well as the details of the technique are described in this article.