Photothermal characterization of refractories for the steel industry

The companion paper (''Non-destructive Characterisation of Refractories by Mirage Effect and Photothermal Microscopy'', by G. Savignat, P. Boch, L. Pottier, D. Vandembroucq, and D. Fournier, in the same EUROMAT meeting) has explained the potential of photothermal techniques for the non-destructive evaluation of refractories. The present study gives photothermal data for three sorts of refractories: carbon bonded alumina, aluminium nitride / boron nitride bonded alumina, and carbon-bonded magnesia. The mirage effect and the photothermal microscopy are shown to be complementary methods, able to bring information about both macroscopic and microscopic thermal diffusivity. (orig.)