To improve gas turbine performance, it is possible to decrease back flow gases in the high-temperature combustion region of the turbo machine by reducing the shroud/rotor gap. Thick and porous thermal barrier coating (TBC) systems and composite CoNi-CrAlY/Al2O3 coatings made by air plasma spray and composite NiCrAlY/graphite coatings made by laser cladding were studied as possible high-temperature abradable seal on shroud. Oxidation and thermal fatigue resistance of the coatings were assessed by means of isothermal and cyclic oxidation tests. Tested CoNiCrAlY/Al2O3 and NiCrAlY/graphite coatings after 1000 h at 1100 C do not show noticeable microstructural modification. The oxidation resistance of the new composite coatings satisfied original equipment manufacturer (OEM) specifications. Thick and porous TBC systems passed the thermal fatigue test according to the considered OEM procedures. According to the OEM specifications for abradable coatings, the hardness evaluation suggests that these kinds of coatings must be used with abrasivetipped blades. Thick and porous TBC coating has shown good abradability using tipped blades.

Studio per lo sviluppo di nuovi rivestimenti ceramico compositi impiegabili in sistemi abradibili / U. Bardi; C. Giolli; A. Scrivani; G. Rizzi; F. Borgioli; A. Fossati; K. Partes; T. Seefeld; D. Sporer; A. Refke; C. Giordano. - In: LA METALLURGIA ITALIANA. - ISSN 0026-0843. - STAMPA. - 102 (11-12):(2010), pp. 3-9.

Studio per lo sviluppo di nuovi rivestimenti ceramico compositi impiegabili in sistemi abradibili

BARDI, UGO;BORGIOLI, FRANCESCA;
2010

Abstract

To improve gas turbine performance, it is possible to decrease back flow gases in the high-temperature combustion region of the turbo machine by reducing the shroud/rotor gap. Thick and porous thermal barrier coating (TBC) systems and composite CoNi-CrAlY/Al2O3 coatings made by air plasma spray and composite NiCrAlY/graphite coatings made by laser cladding were studied as possible high-temperature abradable seal on shroud. Oxidation and thermal fatigue resistance of the coatings were assessed by means of isothermal and cyclic oxidation tests. Tested CoNiCrAlY/Al2O3 and NiCrAlY/graphite coatings after 1000 h at 1100 C do not show noticeable microstructural modification. The oxidation resistance of the new composite coatings satisfied original equipment manufacturer (OEM) specifications. Thick and porous TBC systems passed the thermal fatigue test according to the considered OEM procedures. According to the OEM specifications for abradable coatings, the hardness evaluation suggests that these kinds of coatings must be used with abrasivetipped blades. Thick and porous TBC coating has shown good abradability using tipped blades.
2010
102 (11-12)
3
9
U. Bardi; C. Giolli; A. Scrivani; G. Rizzi; F. Borgioli; A. Fossati; K. Partes; T. Seefeld; D. Sporer; A. Refke; C. Giordano
File in questo prodotto:
File Dimensione Formato  
giolli.pdf

Accesso chiuso

Tipologia: Versione finale referata (Postprint, Accepted manuscript)
Licenza: Tutti i diritti riservati
Dimensione 346.14 kB
Formato Adobe PDF
346.14 kB Adobe PDF   Richiedi una copia

I documenti in FLORE sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificatore per citare o creare un link a questa risorsa: https://hdl.handle.net/2158/624390
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 1
  • ???jsp.display-item.citation.isi??? 0
social impact