Role of platinum in aluminide coatings

Effects of Pt incorporation on the isothermal oxidation behavior of chemical vapor deposition aluminide coatings

“…From an oxidation standpoint, these elements have the potenTa, W, and Re were slightly higher and less uniform in the as-deposited NiAl, compared to the more homogeneous tial to accelerate the growth and degrade the adherence of a protective alumina scale. [34] Earlier studies [17] reported that distribution in (Ni,Pt)Al, but absolute comparisons must be made with caution due to the poor resolution of the microa relatively thick Pt layer (ϳ25 m) excluded refractorymetal elements from the outer PtAl 2 layer of as-deposited probe technique at concentrations in the range of 1 wt pct. Tantalum appeared to diffuse outward more slowly in the high-activity coatings prepared by pack cementation.…”

Cyclic oxidation of Pt/Pd-modified aluminide coating on a nickel-based superalloy at 1150°C

“…This coating forms a stable oxide scale, such as Al 2 O 3 or Cr 2 O 3 , and acts as a diffusion barrier to damage species such as oxygen, nitrogen, and sulfur [1]. Pt increases coating stability by eliminating chromium-rich precipitation from the outer coating layer and preventing the diffusion of refractory transition elements, such as molybdenum, vanadium, and tungsten, into the outer coating layer [2,3]. Therefore, platinum-modified aluminide coatings are barriers with stiff resistance at high temperatures [4].…”

Effect of zirconium addition on cyclic oxidation behavior of platinum-modified aluminide coating on nickel-based superalloy

“…Among the various coatings, Pt-modified aluminide coatings ensure the protection of nickel-base superalloys from oxidative gases at gas temperatures up to 1400 C [2], and are widely used for aero and industrial gas turbine blades [3]. According to several studies [4][5][6], the stability of the protective coating is enhanced by the presence of Pt in an oxidative environment.…”