A collection of AlSi7 closed cell foams of densities between 500 kg/m3 and 1300 kg/m3 were produced following the powder metallurgical route [1,2]. On the one hand, thermal conductivity of the samples has been measured by means of the transient plane source (TPS) technique [3,4]. Values obtained showed the increase of thermal conductivity values with density. On the other hand, the TPS technique has been tested as a tool to detect in-homogeneities derived from the manufacturing process. The results obtained have proved the ability of this method to detect these in-homogeneities, and its possible use as a non – destructive quality control method.