Laser surface modification of plasma sprayed yttria stabilised zirconia coatings on type 316L stainless steel
Authors: Shankar, A. Ravi; Mudali, U. Kamachi
Source: Surface Engineering, Volume 25, Number 3, April 2009 , pp. 241-248(8)
Publisher: Maney Publishing
Abstract:Plasma sprayed yttria stabilised zirconia/NiCrAlY thermal barrier coatings proposed for molten LiCl–KCl salt environments contain pores and microcracks that may cause corrosion of the substrate on prolonged exposure. In the present work the as sprayed samples were laser remelted with various scan speeds of 1, 2·5 and 5 mm s?1 to reduce the segmented cracks. Microstructural inhomogeneities like pores and voids have been eliminated on laser remelting, however, segmented cracks were formed irrespective of scan speed. Distinct interface separating fine and coarse grains were observed at all scan speeds. The microhardness of the glazed surface improved and surface roughness was reduced. The beneficial non-transformable tetragonal phase was formed after laser remelting while the as sprayed coating consisted of insignificant monoclinic phase. An attempt was made to seal the pores of the zirconia coating by applying ZrO2 and ZrO2 + SiO2 powder.
Document Type: Research Article
Publication date: 2009-04-01
- Authors wishing to cite fast track papers should give the journal name and the article DOI. This will enable reference linking via CrossRef and allow forward and backward citation tracking systems to associate the fast track citation with the final journal reference.
This journal features top 10 articles which are freely available. Please click here and click on the 'Top articles' link in the right-hand menu to view the list and start downloading.
- Editorial Board
- Information for Authors
- Subscribe to this Title
- Terms & Conditions
- Online submission site
- ingentaconnect is not responsible for the content or availability of external websites