Abstract: A method of manufacturing a hollow machine blade consisting of two skins ining an internal cavity and interconnected by stiffeners comprises:forging and machining the primary components of the blade, including forming a reserve of material in localized regions of the inner faces of the skins, trunnion forming elements at the ends of the components, and locating holes in the components;deposition of diffusion barriers involving application of a mask, cutting the mask to a predetermined pattern using a special-purpose tool, peeling away portions of the mask, deposition of a coating product, peeling away the remainder of the mask, prefiring treatment, cleaning and checking;assembly of the primary components followed by isostatic-pressure diffusion welding; andsubjecting the assembly to inflation under gas pressure and superplastic forming in a mould in order to shape the skins and form the interconnecting stiffeners, including the steps of cold-debonding the primary components, causing flow of the material reser