Thermal conductivity of plasma sprayed forsterite/mullite coatings

In this study, the thermal diffusivities of freestanding mullite and forsterite coatings and a two-layer forsterite/mullite sample were measured, using the laser flash method, and compared with the theoretical values. To achieve this goal, the thermal properties of forsterite, mullite, and a forsterite/mullite multilayer coating deposited with a DC-arc plasma-spray gun were investigated, and the thermal diffusivity for the coatings were calculated and measured. The apparent thermal diffusivity values for the forsterite/mullite-layered sample were compared with the theoretical apparent thermal diffusivity values that were determined by calculating the sum of the data for each layer. A link between the coating characteristics and the results of the experiments are provided. (C) 2014 Elsevier Ltd and Techna Group S.r.l. All rights reserved.