The invention concerns a hollow, single-piece bladed disc such as a compressor or turbine disc in an aeronautic or industrial gas turbine and more particularly concerns a method to manufacture said disc.
Composite materials, notably those consisting of a fibrous reinforcement structure densified by a matrix, are increasingly being used to manufacture structural parts, in particular because they allow a reduction in weight but with equal performance compared with metal materials.
The use of said materials has been proposed for gas turbine parts, whether these are parts located in “cold portions” during operation or are elements located in “hot portions” during operation.
As examples, mention may be made of document US 2005/0 084 377 which describes the manufacture of a fan blade in composite material with a woven fibrous reinforcement and polymer matrix, and document US 2010/005 780 which describes the manufacture of a lobed mixer in a ceramic matrix composite material (CMC) for a turbo fan engine
However, the techniques described in these documents are not suitable for parts of even more complex shape such as a hollow, single-piece bladed disc.
The manufacture of a bladed disc in a single piece and in a composite material with fibrous reinforcement is proposed by document FR 2 631 083. Flanges and vanes of the disc are obtained by continual winding of a cable or yarn which follows axial pathways for the blades and extends in substantially radial planes for the flanges. The method requires the use of highly complex dismountable tooling to define the spaces in which the cable or yarn is wound. In addition, in the blades, the direction of the fibrous reinforcement is axial, which is not optimal with respect to the direction of applied forces.