Microstructural Characterization of Thermal Barrier Coatings Glazed by a High Power Laser

Abstract

Plasma-sprayed thermal barrier coatings were laser-glazed by a high power laser in order to modify the structures. The microstructure of laser-glazed TBCs is investigated. The result indicates that a smooth and dense glazed surface with craters and a network of microcracks is obtained after laser-glazing. The laser-glazed region consists of a columnar microstructure. There are segmentation microcracks in the laser-glazed coatings, which don’t run through the coatings along thickness. Surface roughness has been reduced significantly for the laser treated ceramic coatings