Thermal barrier coatings (TBCs), consisting of physical vapor deposited (PVD) partially stabilized zir-conia (PSZ, 8 wt. %Y203) and a diffusion aluminide bond coat, were characterized as a function of time after oxidative isothermal heat treatment at 1373 K in air. The experimental characterizations was conducted by X-ray diffraction analysis and scanning electron microscopy (SEM) with energy-d...

The evolution of the surface roughness of an initially flat platinum-modified nickel aluminide (NiPtAl) coating on a single crystal superalloy with cyclic oxidation has been measured by optical profilometry and correlated with the aluminide microstructure. The roughness evolution is dominated by the relative motion of individual grains on thermal cycling, with the larger sized grains moving up ...

Nickel base superalloy alloys are used in the manufacture of gas turbine engine components, which in use are exposed to high temperatures and corrosive environments. The platinum aluminide coatings described here have been developed to protect nickel base superalloy alloys from oxidation. In this study, the effect of cyclic oxidation, platinum layer thickness and aluminizing process on beha...

Corrosion-resistant coatings based on the iron aluminide intermetallic compound Fe3Al are currently being investigated for fossil energy applications. Fe3Al possesses excellent intrinsic high-temperature oxidation and sulfidation resistance, and a significant effort has been made in the development of bulk alloys based on it. While substantial progress has been made, the widespread use of these...

Aluminide coating is prepared on K438 Ni-based superalloy by pack cementation. The hot corrosion test of as-received and pre-oxidation aluminide in Na 2 SO 4 salt are carried out at 1050°C. morphologies, phase composition, products characterized XRD, SEM, EDS, TEM. conclusion that the has excellent properties. After corrosion, oxide scale thinnest maintains good integrity. However, fluctuates g...

Abstract: activity gas diffusion process has been investigated in this research. Effects of coating temperature and aluminumconcentration in powder mixture on formation mechanism were studied using optical and scanning electronmicroscopes, EDS and X-ray diffraction (XRD) techniques. For this purpose two different packs containing 1 and 2wt% aluminum powder, were used for coating the samples at ...

Pd+Zr and Pd+Hf co-doped aluminide coatings were deposited on the Mar-M247 nickel superalloy by palladium electroplating followed zirconizing-aluminizing or hafnizing-aluminizing processes. Both consisted of two zones, outer interdiffusion one build ?-(Ni,Pd)Al phase. Hafnium zirconium formed inclusions that precipitated at border zones close to surface (only in Zr+Pd modified coating). Oxidati...