Aa. Bruna et al., Protective coatings for aeronautic and power generation turbines components deposited by plasma spray, B S ESP CER, 39(4), 2000, pp. 540-547
Citations number
8
Categorie Soggetti
Material Science & Engineering
Journal title
BOLETIN DE LA SOCIEDAD ESPANOLA DE CERAMICA Y VIDRIO
Coatings produced by aluminium diffusion, called aluminide are employed to
increase the oxidation and corrosion resistance, increasing the life of Ni
and Co base superalloys components at temperatures comprised between 900 an
d 1050 degrees C. Consequently these coatings are frequently employed in ae
ronautic and Fewer generation turbines as well as in the chemical industry.
Aluminides are industrially produced by pack cementation or CVD and recent
ly it has been demonstrated that its resistance significantly increases whe
n Cr is added (chrome-aluminides). During this work, a feasibility study ha
s been carried out in order to determine if plasma spray can be employed fo
r depositing this type of coatings on turbine blades. Therefore, aluminium
and aluminium/chromium layers were deposited on Ni base IN100 superalloy sp
ecimens that were subsequently subjected to a diffusion heat treatment unde
r Ar flow Characterisation and analysis of the coatings were carried out by
metallography, SEM and EDS. Cyclic oxidation tests were carried out at 105
0 degrees C while molten sulphate hot corrosion was performed at 900 degree
s C. The results of this preliminary study are promising and indicate that
plasma spray can be developed as an industrial process for production of al
uminide and chrome-aluminide coatings.