Influence of Pt concentration on structure of aluminized coatings on a Ni base superalloy

Effect of pre-oxidation treatments on the structural, microstructural, and chemical properties of β-(Ni,Pt)Al system

“…In this regard, it is well known that Pt retards the formation of mature voids injected due to the accumulation of Kirkendall vacancies and it occupies preferentially Ni sites in -(Ni,Pt)Al alloy in comparison with non-Pt-containing alloys, e.g., -NiAl [18,20,21]. while the Cr site preference is dependent of the composition and temperature [26][27][28].…”

“…In this regard, it is well known that Pt retards the formation of mature voids injected due to the accumulation of Kirkendall vacancies and it occupies preferentially Ni sites in -(Ni,Pt)Al alloy in comparison with non-Pt-containing alloys, e.g., -NiAl [18,20,21]. The decrease in Al content is also related with increased mobility caused by the presence of Pt which decreases the Al activation energy promoting the faster formation of an Al2O3 scale on the BC surface [20,22]. Plotting the chemical compositions in this diagram at the different pre-oxidation temperatures, is an approach that allow observing the diffusion path and comparing to the structural evolution in the specimens.…”

“…Variation in the chemical composition of the bond coat along the cross section at the different temperatures tested.The decrease in Al content is also related with increased mobility caused by the presence of Pt which decreases the Al activation energy promoting the faster formation of an Al2O3 scale on the BC surface[20,22].…”

The Influence of Pd on the Structure and Oxidation Performance of β-NiAl Diffusion Coatings

“…For coatings processed on the same substrate, contrasting behaviors are observed when the influence of Pd and of Pt on the mobility of Al and Ni in the intermetallic layer are compared: unlike Pd, Pt causes an increase in coating thickness 30 associated with enhanced mobility of Al in the microstructure of β-(NiAl) 31,32 . To understand the impact of Ti and Cr on oxidation performance in Pd-and Pt-modified coatings, it is important to identify how their distribution is altered in these coatings.…”

Deposition of Al2O3 ceramic film on copper‐based heterostructured coatings by aluminizing process: Study of the electrochemical responses and corrosion mechanism of the coating

“…The diffusion coating method is widely used to create aluminide coatings on various alloys, especially nickel‐based superalloys. Aluminizing process on nickel‐based alloys leads to the formation of aluminides such as NiAl, Ni 2 Al 3 , NiAl 3 , and Ni 3 Al . The phase composition of diffusion coatings are determined by the activity of the environment used for the aluminizing process, the aluminizing temperature, the thermodynamics of the aluminide formation reactions, the kinetics of the diffusion process and the chemical and phase composition of the base metal …”