ALUPLAT (Degradation of Aluminide coatings on Platinum-containing model and real superalloys)

The composition, microstructure and crystal phases (γ/γ′) of Ni-based superalloys are optimized from decades to provide adequate mechanical strength of aero-engine components operating at high temperatures in harsh environments. The next generation of superalloys for turbines will lead to the introduction of Pt in the superalloys, like with the brand new “TROPEA” single crystal nickel-based superalloy.

However, their Al and Cr content is limited to introduce higher amounts of refractory elements (e.g. Re, Mo, Ta) and increase the mechanical resistance. Therefore, environmental protection should be supplied through Al-based diffusion coatings that form protective oxides.

The main aim of the “ALUPLAT” project is to study the combined environmental and mechanical degradation of these very new Pt-containing Ni-based superalloy “TROPEA” in uncoated and Al/Si/rare earth (RE)-coated conditions.

The role of the partition and content of the other alloying elements in the superalloy is unknown and requires a thorough investigation on separately γ and γ′ then on combined γ/γ′ model alloys.

Interdiffusion between coating and substrates as well as the coating efficiency facing oxidation and type I and II hot corrosion will be evaluated trough this project.