[Kovove materialy - Metallic materials]
    Mon - January 25, 2021 - 15:07 No. of hits : 1227840 ISSN 1338-4252 (online) ISSN 0023-432X (printed)
© Institute of Materials and Machine Mechanics, Slovak Academy of Sciences, Bratislava, Slovak Republic

VOLUME 43 (2005), Issue 5

Chemical stripping methods for the removal of NiCrAlY thermal spray coatings
SCRIVANI, A., RIZZI, G., BARDI, U.
vol. 43 (2005), no. 5, pp. 382 - 387

Abstract
The present paper is focused on the "stripping" of serviced blades and vanes for gas turbine, which need the removal of the coating in order to be repaired and refitted with a new coating. The stripping process requires, normally, the separate removal of the top coat (Yttria Partially Stabilized Zirconia, YPSZ) and of the bond coat (MCrAlY where M stays for Co, Ni or both). The present paper examines only chemical procedures able to remove the NiCrAlY bond coat. The blades and vanes surfaces after removal of NiCrAlY coatings were characterized from the point of view of surface morphology, metallurgical structure and chemical composition. The efficiency of the acid solution in NiCrAlY removal has been investigated and the behaviour of two Ni based alloys substrates in aggressive environment has been tested. The HCl based stripping solution shows good performances in Vacuum Plasma Sprayed NiCrAlY coatings removal from Ni superalloys. The tested stripping procedure is fast and safe because no damage to base materials has been noted.

Key words
coating, plasma spraying, nickel alloys

[open article.pdf] Full text (159 KB)

[IMMS SAS]      UMMS SAV - Bratislava (SK) Personal data Protection   ver. 1.7.2      [go to HOME PAGE]
Full title of this journal is bilingual: Kovové materiály - Metallic Materials.
The official abbreviation in accordance with JCR ISI is Kovove Mater.


Article abstracts updated: 2021-01-15 08:18      
Articles in press revised: 2020-10-30 12:09     
Full text pdf uploaded: 2020-11-09 13:07    
Information updated: 2020-06-29 17:09   
Code last revised: 2020-06-29 16:48  

© OldSoft, 2004, …, 2021