The present invention relates to the general field of aeroengine gas turbine blades that are made of composite material and that have a leading edge and/or a trailing edge fitted with metal structural reinforcement.
A field of application of the invention is that of turbine engine fan blades or propeller blades. Another field of application of the invention is that of outlet guide vanes (OGV) for turbine engines.
It is known for turbine fan blades that are made of composite material to be fitted with metal structural reinforcement extending over the full height of the blades and beyond their leading edges. The same applies to outlet guide vanes.
Such structural reinforcement enables a set of composite blades to be protected against the fan being struck by a foreign body, such as a bird ingested by the engine, for example. In particular, the metal structural reinforcement serves to protect the leading edge (or the trailing edge) of a composite material blade by avoiding risks of delamination, of fibers breaking, or indeed of damage as a result of loss of cohesion between fibers and the matrix.
In general, the structural reinforcement comprises pieces of titanium made by milling from a block of material, and those pieces are adhesively bonded directly on the outer profile of the blade to be protected.
Nevertheless, adhesively bonding a piece of structural metal reinforcement raises several problems. In particular, it is difficult to obtain a satisfactory thickness of adhesive over all of the areas of contact areas between the metal reinforcement and the blade. Furthermore, with varying viscosity between different batches of adhesive, it is impossible to ensure equal thickness for the layer of adhesive under constant fabrication conditions.
There therefore exists a need to have a method that makes it possible to ensure that structural metal reinforcement can be adhesively bonded onto a blade in reproducible manner, in particular in terms of the layer of adhesive having a well-controlled thickness.
USPTO Backgrounds
USPTO Backgrounds