Aircraft part made of superalloy comprising rhenium and/or ruthenium and associated manufacturing method

A method for manufacturing a part, comprising the steps of:

• a) chemical attack, in a wet acid medium, of at least a portion of a surface of a substrate made of a monocrystalline superalloy, comprising at least one element chosen from rhenium and ruthenium, the substrate having a γ-γ′ phase, the substrate having an average mass fraction of rhenium and/or ruthenium greater than or equal to 3%, the chemical attack being carried out in such a way that the average mass fraction of rhenium and/or ruthenium over the portion of the surface of the substrate is less than 2%, and such that the at least a portion of the surface of the substrate has an arithmetic average roughness Ra between 0.5 μm and 5 μm, the arithmetic average roughness Ra being measured over an area greater than 1 mm2,
• b) depositing on the at least a portion of the substrate a protective coating having a γ-γ′ phase and an average mass fraction of rhenium and/or ruthenium of less than 1%.