Method for producing a part, in particular a part made from a composite material
A method for producing a part, in particular a part made of composite material, in particular for a turbomachine, including at least: a step of producing a preform, during which a fibrous preform intended to form an outer skin of the part is produced; a step of producing a core, during which a rigid core, in particular a hollow rigid core, intended to form a framework of the part is produced; an insertion step, during which the rigid core is inserted into the fibrous preform, an injection step, during which a matrix is injected into the fibrous preform; and a heat-treatment step, during which polymerisation of the matrix is carried out.
1 . A method for producing a part, made of composite material, for a turbomachine, comprising at least:
a step of producing a preform, during which a fibrous preform intended to form an outer skin of the part is produced;
a step of producing a core, during which a hollow rigid core, intended to form a framework of the part is produced, the hollow rigid core comprising an inner cavity subdivided into a plurality of cavities by stiffeners, and further comprising an inner recess defining a space intended to receive a spar;
an insertion step, during which the hollow rigid core is inserted into the fibrous preform and during which a spar is inserted into the inner recess of the hollow rigid core,
an injection step, during which a matrix is injected into the fibrous preform; and
a heat-treatment step, during which polymerisation of the matrix is carried out.
2 . The method for producing a part according to claim 1 , wherein the hollow rigid core is produced so as to have a shape equivalent to the composite material part intended to be produced.
3 . The method for producing a part according to claim 1 , wherein the hollow rigid core is a shell comprising at least one side wall enclosing a cavity.
4 . The method for producing a part according to claim 1 , wherein the hollow rigid core comprises a thermoplastic and/or thermosetting material.
5 . The method for producing a part according to claim 1 , wherein the hollow rigid core comprises a material for which a heat deflection temperature and a glass transition temperature are greater than a polymerisation temperature of the matrix used during the injection step.
6 . The method for producing a part according to claim 1 , wherein the hollow rigid core comprises at least one of the materials from a polyaryletherketone, a polyetherimide and/or a semi-aromatic polyamide.
7 . The method for producing a part according to claim 1 , wherein the hollow rigid core is formed:
in a single operation, by additive manufacturing, or in a mould and comprises at least two parts assembled and fixed together, by fusion, welding or gluing.
8 . The method for producing a part according to claim 1 , comprising, after the step of producing the core, a surface treatment step, during which a surface treatment of the hollow rigid core is carried out, in particular comprising application of an adhesive on an outer surface of the hollow rigid core.
9 . The method for producing a part according to claim 1 , comprising a finishing step, during which the part is adjusted to the desired dimensions.
10 . The method for producing a part according to claim 1 , wherein the part to be produced is a turbomachine blade.
11 . The method of producing a part according to claim 1 , wherein the stiffeners include first stiffeners spaced apart from one another along a first direction.
12 . The method of producing a part according to claim 11 , wherein the stiffeners include second stiffeners spaced apart from one another along a second direction perpendicular to the first direction.
13 . The method of producing a part according to claim 12 , wherein the hollow rigid core includes a side wall, an upper wall, and a lower wall, wherein the vertical stiffeners and the horizontal stiffeners are formed as a single piece with the side wall, the upper wall, and the lower wall.
14 . The method of producing a part according to claim 12 , wherein the fibrous preform includes a non-interlinked area extending over a part of a length of the fibrous preform.
15 . The method for producing a part according to claim 1 , wherein the fibrous preform is formed by a fibrous texture produced in a single part by three-dimensional or multilayer weaving.
16 . The method of producing a part according to claim 1 , wherein the method further comprises:
a compacting step, during which pressure is applied to the fibrous preform to press the fibrous preform against a side wall of the hollow rigid core.