Characterizations of the pore-crack network architecture of thermal-sprayed coatings

This study aims at developing three techniques permitting to complementary characterize the architecture of the pore-crack network architecture of thermal-sprayed coatings: (i) image analysis quantifies the coating porous morphology, that is to say the overall porosity level and the crack network orientation; (ii) electrochemical analysis qualitatively characterizes the ratio of connected pores; (iii) Archimedean porosimetry quantifies the non-connected porosity level. These techniques were applied to characterize the pore structure of yttria-partially stabilized zirconia (Y-PSZ) thermal barrier coatings (TBCs) manufactured implementing air plasma spraying and hybrid plasma spraying, which combines plasma spraying and laser remelting. Thermal and mechanical properties of Y-PSZ TBCs are especially dependant from their pore network architecture. (C) 2004 Elsevier Inc. All rights reserved.