GEOMETRY OF A SUPPORT SURFACE

Description

Domaine Technique

[0001] The present invention relates to the manufacture of composite material parts by draping them onto a surface. In particular, but not exclusively, the invention relates to the manufacture of aircraft engine casings. Technique antérieure

[0002] The use of composite materials for the manufacture of aeronautical parts, for example for aeronautical engine casings, makes it possible to obtain parts that are resistant and have mechanical performance equivalent to or even superior to those made of metal, while having a much lower mass.

[0003] It is known to produce composite parts by draping pre-impregnated fibrous structures over a surface. For reasons of production cost and repeatability, the draping can be performed automatically, using the automated fiber placement (AFP) technique. An example of a manufacturing process for a composite part using the AFP method is described in document FR3062336B1.

[0004] However, when it is desired to produce parts comprising a body of partial revolution at the end or ends of which flanges extend, with a restricted angle between the body and at least one flange, in particular an acute angle of 90° or less, the head or roller for depositing fibrous structures does not allow access to the bottom of said angle.

[0005] Thus, to produce parts with such angles, the draping is carried out with larger angles to allow passage of the dispensing head or roller, and then the draped structure is deformed to obtain the desired angles. Such solutions are described, for example, in documents WO 2018 / 007756 and WO2012 / 046020.

[0006] In document WO 2018 / 007756, to produce a final part comprising a flange and a half-shell-shaped body with a given final radius, an intermediate half-shell-shaped preform is first draped. This preform has a smaller radius than the desired final radius and, consequently, a larger angle between the body and the flange, which allows for draping at that angle. Once the draping is complete, the resulting intermediate preform is deformed to the desired final radius, thus deforming the flange to achieve the required angle between the flange and the body.

[0007] In document WO2012 / 046020, a part is made comprising a cylindrical body and a circular flange extending perpendicularly to the cylindrical body according to the preamble of claim 1.

[0008] The draping process is carried out by draping the portion intended to form the flange in line with the draping of the portion intended to form the cylindrical body. Then, the portion intended to form the flange is deformed to position it perpendicular to the axis of revolution of the body. During draping, the portion intended to form the flange exhibits circumferential undulations of increasing amplitude as one approaches the free end of said portion, so as to obtain a smooth flange after deformation.

[0009] However, in the solutions described, the mechanical deformation of the draped structure leads to deformations of the draped fibrous structures and significant stresses in the fibers, particularly near the apex of the angle. These deformations are further accentuated when a fillet is present between the flange and the body, or when the angle between the flange and the body is less than 90°. Exposé de l'invention

[0010] The present invention aims to overcome the aforementioned drawbacks. To this end, the present invention proposes a method for determining the geometry of a draping mold for producing a roughing of a part made of composite material, said part comprising a body of partial revolution with an axis directed along an axial direction and having one or more given reference radii along said axial direction, said body extending partially around the axial direction in a circumferential direction, and said part comprising at least one flange extending from one end of the body in an extension direction, the method comprising: the determination of a first surface of revolution with an axis directed along the axial direction, said first surface extending around the axial direction along the circumferential direction, the determination of a second surface located in the extension of the first surface along a direction of extension, the angle formed between the axial direction and the direction of extension being greater than the angle formed between the axial direction and the direction of extension, the second surface having undulating curves along the circumferential direction following each other successively along the direction of extension, each circumferential undulating curve corresponding to an arc of a circle belonging to the flange to be produced, the curvilinear length of said undulating curve corresponding to the length of said arc of a circle, the process being characterized in that the radius or radii presented by the first surface of revolution along the axial direction are less than the reference radius or radii for the same position along the axial direction, said first surface corresponding to a curvature along the circumferential direction of a surface having the shape of the body to be produced, and in that the second surface has correction curvatures in the extension direction, so that all points of each circumferential undulation curve are at the same curvilinear distance from the junction between the first surface and the second surface, said curvilinear distance belonging to the second surface and having a value corresponding to the curvilinear distance between the arc of the circle belonging to the flange to be produced corresponding to said circumferential undulation curve, and the junction between the flange and the body to be produced.

[0011] The first surface is intended to be the draping surface onto which the rough form of the body of the part to be made will be draped. The second surface is intended to be the draping surface onto which the rough form of the flange of the part to be made will be draped.

[0012] The angle formed between the axial direction and another direction shall be understood as the angle directed from the body, or the surface corresponding to the body, towards the flange, or the surface corresponding to the flange, said angle being measured from the part of the axial direction located on the side of the body or the surface corresponding to the body towards the nearest part of said other direction.

[0013] The curvilinear distance or length between a point on a circumferential undulation curve and the junction between the first surface and the second surface is defined as the smallest curvilinear distance belonging to the second surface and allowing one to join said point on the circumferential undulation curve to said junction.

[0014] The curvilinear distance or length between a circular arc and the junction between the flange and the body is defined as the smallest curvilinear distance belonging to the flange and allowing a point on the circular arc to be joined to said junction.

[0015] Thus, by creating corrective curves in the extension direction, stresses in the fibers are limited following the shaping of the draped blank to obtain the preform of the part. Indeed, circumferential undulations generate length discrepancies in the extension direction, which are rectified using these corrective curves. Furthermore, determining different curvilinear lengths between the circular arcs belonging to the flange and the junction between the flange and the body allows the radius of any fillet between the flange and the body to be taken into account from the mold design stage. Therefore, during the shaping of the draped blank to obtain the preform of the part, stresses in the fibers are limited at the location of this fillet.

[0016] Furthermore, by creating a first draping surface for the body blank with a smaller radius than the radius of the body to be manufactured, the angle between the first surface and the second surface intended for the flange blank is further increased, which further facilitates the passage of the draping head and the application of the fibrous structures at the junction between the first and second surfaces.

[0017] According to a particular feature of the invention, the inflection points of each circumferential undulation curve are contained within the same circle.

[0018] According to another particular feature of the invention, the minima of each circumferential undulation curve are contained within the same circle whose radius is greater than or equal to the radius of the arc of the circle forming the junction between the first surface and the second surface.

[0019] According to another particular feature of the invention, the minima of each circumferential undulation curve are contained within the same circle whose radius is identical to the arc of the circle forming the junction between the first surface and the second surface.

[0020] This ensures that the least possible stress is obtained in the fibers during the deformation of the fibrous blank.

[0021] According to another particular feature of the invention, the correction curves located on the maxima of the circumferential undulations have larger radii of curvature than the correction curves located on the inflection points of the circumferential undulations.

[0022] Indeed, circumferential undulations distort the second surface and can therefore create material gaps at the maxima of the circumferential undulations. Thus, by using more curved correction curves at the maxima of the circumferential undulations, more material can be added to these areas.

[0023] According to another particular feature of the invention, the angle between the axial direction and the extension direction is less than or equal to 120° and the angle between the axial direction and the extension direction is greater than 120°.

[0024] According to another particular feature of the invention, the flange to be produced includes a fillet at its junction with the body to be produced.

[0025] The invention further relates to a method for manufacturing a part made of composite material comprising a partially rotating body with an axis directed along an axial direction having one or more given reference radii along the axial direction, said body extending partially around the axial direction in a circumferential direction, and at least one flange extending from one end of the body in an extension direction, the method comprising: the formation of a fibrous blank of the part to be obtained by depositing a plurality of fibrous plies by automatic placement of fibers on a draping mold comprising a first draping surface and a second draping surface located in the extension of the first draping surface, the first draping surface and the second draping surface corresponding respectively to at least the first surface and the second surface determined according to the method of determining a geometry of a draping mold according to the invention, the portion of the blank produced on the first draping surface corresponding to a blank of the body and the portion of the blank produced on the second draping surface corresponding to a blank of the flange, the shaping of the fibrous blank so as to obtain a fibrous preform,said shaping process includes the deployment of the body blank along the circumferential direction to obtain a body preform having the reference radius along the axial direction and having the shape of the body to be produced, and the shaping of the flange blank to obtain a flange preform extending from the end of the body preform along the extension direction and having the shape of the flange to be produced, and then the densification of the fibrous preform by a matrix to obtain the composite material part.

[0026] Thus, the flange blank has undulations corresponding to the circumferential undulation curves and correction curves of the second draping surface.

[0027] According to a particular feature of the invention, the deployment of the body blank and the shaping of the flange blank are carried out simultaneously.

[0028] Thus, the shaping of the fiber blank to obtain the fiber preform for densification is carried out in a single step, with the undulations present on the flange blank being completely smoothed during this single step. This method is therefore simplified and faster. Consequently, an intermediate shaping step is eliminated.

[0029] According to another particular feature of the invention, an intermediate shaping of the flange blank is first carried out so as to obtain an intermediate flange preform extending from the end of the body blank along an intermediate extension direction, the angle between the intermediate extension direction and the axial direction being less than the angle between the extension direction and the axial direction but greater than the angle between the extension direction and the axial direction, then the body blank is deployed so as to obtain the body preform and so as to carry out the shaping of the intermediate flange preform in order to obtain the flange preform extending from the end of the body preform along the extension direction and having the shape of the flange to be produced.

[0030] In this embodiment, the intermediate shaping step of the flange blank, which partially folds the flange blank while smoothing out the corrugations, and the unfolding step of the body blank, which fully shapes the flange blank, are performed separately. In this embodiment, the intermediate flange preform no longer contains corrugations. This results in better control over each of these operations. Furthermore, by performing these two steps separately, it is possible, for example, to carry out compaction after the intermediate shaping of the flange blank and before the unfolding of the body blank.

[0031] The invention further relates to a method for manufacturing a part made of composite material comprising a body of complete revolution with an axis directed along an axial direction having one or more given reference radii, said body extending partially around the axial direction in a circumferential direction, and at least one flange extending from one end of the body in an extension direction, the method comprising: the production of part sectors comprising a partial revolution body sector with axis directed along an axial direction having the given reference radius, said body sector extending partially around the axial direction along a circumferential direction, and at least one flange sector extending from one end of the body sector along an extension direction, the manufacture of said part sectors being carried out according to the manufacturing process of the invention described above, the assembly of the part sectors to obtain the composite material part having a complete revolution.

[0032] Thus, the draping mold geometry of the invention makes it possible not only to produce parts with a partial revolution, but also parts of complete revolution by assembling several sectors of a part of partial revolution. Brève description des dessins

[0033] [ Fig. 1 ] There figure 1 is a three-dimensional view of a part that can be produced using a draping mold according to the invention, comprising a body and at least one flange. Fig. 2A ] There figure 2A is a schematic cross-sectional view of the part of the figure 1 at the level of the first shelf of the room. Fig. 2B ] There figure 2B is a schematic cross-sectional view of the part of the figure 1 at the level of a second shelf in the room. Fig. 2C ] There figure 2C is a schematic cross-sectional view of the part of the figure 1 at the level of a third aisle in the room. Fig. 3 ] There figure 3 is a schematic three-dimensional view of the first surface of a mold according to the invention. Fig. 4A ] There figure 4A is a schematic cross-sectional view of the first surface of the figure 3 at the level of a first radius of said first surface. Fig. 4B ] There figure 4B is a schematic cross-sectional view of the first surface of the figure 3 at the level of a second radius of said first surface. Fig. 4C ] There figure 4C is a schematic cross-sectional view of the first surface of the figure 3 at the level of a third radius of said first surface. Fig. 5 ] There figure 5 is a partial schematic cross-sectional view of the part of the figure 1 for determining the lengths of the circular arcs belonging to the flange. Fig. 6 ] There figure 6 is a partial schematic cross-sectional view of the part of the figure 1 for determining the flange lengths. Fig. 7 ] There figure 7 is a three-dimensional view of the first and second surfaces obtained according to the invention, allowing the creation of a draping mold for the part of the figure 1 . [ Fig. 8 ] There figure 8 is a view of the surfaces illustrated on the figure 7 illustrating circumferential undulations. Fig. 9 ] There figure 9 is a first partial three-dimensional view of the surfaces illustrated on the figure 7 illustrating correction curves. Fig. 10 ] There figure 10 is a second partial three-dimensional view of the surfaces illustrated on the figure 7 illustrating correction curves. Fig. 11 ] There figure 11 is a schematic illustration of a draping mold including the surfaces shown on the figures 7 à 10 . [ Fig. 12 ] There figure 12 is a schematic and partial illustration of the formation of a draped assembly by automatic fiber placement. Fig. 13 ] There figure 13 is a partial schematic illustration of a fibrous blank obtained by draping over the mold illustrated on the figure 11 . [ Fig. 14 ] There figure 14 is a partial schematic illustration of an intermediate fibrous preform obtained by unfolding the blank illustrated on the figure 13 . [ Fig. 15 ] There figure 15 is a partial schematic illustration of a fibrous preform obtained by shaping the blank illustrated on the figure 13 or the intermediate preform illustrated on the figure 14 . [ Fig. 16 ] There figure 16 is a schematic illustration of a complete part of revolution obtained by assembling two parts as illustrated on the figure 1 . Description des modes de réalisation

[0034] There figure 1 Figure 4 illustrates a composite part comprising a body 1 and at least one flange 2. The term "flange" may refer to a collar. Part 4 may be an aircraft engine casing comprising two flanges.

[0035] Body 1 is a partial volume of revolution whose axis of revolution A is directed along an axial direction DA. Body 1 extends partially around its axis of revolution A along a circumferential direction DC. The circumferential direction DC extends circularly in a plane perpendicular to the axial direction DA. Body 1 may have a frustoconical or tubular shape, or any axisymmetric profile.

[0036] The body 1 has one or more given reference radii along said axial direction DA. In each plane perpendicular to the axial direction DA, the reference radius RR1, RR2, RR3 is defined as the distance between the axial direction DA and the arc of a circle formed by the body 1, and corresponds to a position r1, r2, r3 of the axial direction DA, as illustrated in the figures 1, 2A, 2B et 2C . In addition, each position r 1 , r 2 , r 3 is also associated with a length L 1 , L 2 , L 3 of the arc of the circle formed by the body 1 in the plane perpendicular to the axial direction DA and passing through said position r 1 , r 2 , r 3 .

[0037] In the example illustrated on the figures 1, 2A, 2B et 2C The arc of a circle formed by the body 1 of the part 4 in each plane perpendicular to the axial direction DA is intercepted by a reference angle θR of 180°. We do not, of course, depart from the scope of the invention if the reference angle θR intercepting the arc of a circle formed by the body 1 in each plane perpendicular to the axial direction DA is less than 180°, or greater than 180° but strictly less than 360°.

[0038] The flange 2 is present at one end of the body 1, and extends from said end of the body 1. The flange 2 has an annular or frustoconical shape with a partial axis of revolution A directed along the axial direction DA. The flange 2 extends from the body 1 along an extension direction DE.

[0039] Thus, the entire composite part 4 is a partial volume of revolution with axis A directed along the axial direction DA. The extension direction DE is defined for each point of the junction between the body 1 and the flange 2. The extension directions DE at two different points of said junction may be oriented differently. However, the extension directions DE defined for each point of the junction between the body 1 and the flange 2 must intersect at a single point belonging to the axis of revolution A of the part 4.

[0040] In the example shown on the figure 1 The flange 2 forms a 90° angle with the axis of revolution A of the body 1, which corresponds to an extension direction DE perpendicular to the axial direction DA. Furthermore, the flange 2 forms an acute angle of less than 90° with the surface of the body 1 from which it extends, making part 4 particularly difficult to produce using the automated fiber placement method according to prior art techniques. Of course, the invention remains within the scope of this invention if the flange forms an angle of less than 90° with the axis of revolution of the body, which corresponds to an angle of less than 90° between the extension direction and the axial direction. Nor does the invention depart from the scope of this invention if the flange forms an angle greater than 90° with the axis of revolution of the body, provided that this angle is sufficiently small to cause collision problems during the automated draping of said angle.

[0041] We wish to produce part 4 in composite material as illustrated on the figure 1 by draping fibrous structures onto a surface, according to the well-known method of automated fiber placement (AFP). However, the small angle formed between flange 2 and body 1 of part 4 does not allow draping directly onto a surface having the shape of the final part 4. Indeed, this angle does not allow the complete passage of an automatic placement head or roller, and thus results in unsatisfactory placement of the fibrous structures at the bottom of the angle.

[0042] The invention therefore proposes to design a particular draping geometry having a large or even flat angle between a first surface intended to drape the blank of the body 1 and a second surface intended to drape the blank of the flange 2, in order to be able to proceed with the automatic draping of the fibrous structures.

[0043] In order to allow the draped fibrous blank to be shaped at the correct angle without causing significant stress in the draped fibrous structures, and more particularly near the apex of the angle between flange 2 and body 1, it is necessary to design a particular geometry for the draping mold.

[0044] For the sake of simplicity in the figures and description, the first "geometric" surface determined according to the method for determining a draping geometry of the invention and the first "actual" draping surface of the mold are identical and designated by the same reference numeral "100". Similarly, the second "geometric" surface determined according to the method for determining a draping geometry of the invention and the second "actual" draping surface of the mold are identical and designated by the same reference numeral "200". Of course, the invention remains within the scope of the invention if the first and second "actual" draping surfaces correspond only to a portion of the first and second determined "geometric" surfaces.

[0045] The mold includes a first draping surface 100, allowing the draping of the fibrous blank of the body 1, and a second draping surface 200, allowing the draping of the fibrous blank of the flange 2. The second surface 200 of the mold extends in the continuation of the first surface 100 of the mold, along a direction of extension DP.

[0046] Preferably, at every point of the junction between the first surface and the second surface, the tangent of the first surface coincides with the tangent of the second surface.

[0047] The invention remains within the scope of this provision if, at any point along the junction between the first and second surfaces, the tangent of the first surface is slightly inclined relative to the tangent of the second surface, provided that the junction between the first and second surfaces is easily accessible for an automatic fibrous structure dispensing head or roller. Thus, at any point along the junction between the first and second surfaces, the angle between the tangent of the first surface and the tangent of the second surface is typically greater than or equal to 120°, and preferably equal to 180°.

[0048] The first surface 100 is a surface of revolution, partial or complete, whose axis of revolution is directed along the axial direction DA. The length of the first surface 100 along the axial direction DA is at least equal to the length of the body 1 to be manufactured along the axial direction DA.

[0049] The arc of a circle formed by the first surface 100 in each plane perpendicular to the axial direction DA is intercepted by a construction angle θC greater than the reference angle θR, as illustrated in the figures 3, 4A, 4B et 4C The first surface 100 therefore has a more "closed" shape than the body 1 along the circumferential direction DC. In the case where the first surface 100 is a complete surface of revolution, and therefore the arc of the circle formed by the first surface 100 of the mold in each plane perpendicular to the axial direction DA is a complete circle, we consider that the construction angle θ C is equal to 360°.

[0050] Preferably, the transformation ratio, which corresponds to the ratio between the reference angle θR and the construction angle θC, is between 0.6 and 0.8. As an example, a body 1 in the shape of a half-shell, that is to say, having a reference angle θR of 180° as on the figures 1 à 2C , and a first surface exhibiting a complete revolution, that is to say exhibiting a construction angle θ C of 360°, will correspond to a transformation ratio of 0.5.

[0051] The first surface 100 has one or more construction radii along the axial direction DA, as illustrated on the figures 3, 4A, 4B et 4C In each plane perpendicular to the axial direction DA, the construction radius is defined as the distance between the axial direction DA and the arc of the circle formed by the first surface 100. For each position r1, r2, r3 of the axial direction DA corresponding to a reference radius R1, R2, R3 of the body 1, we associate a construction radius RC1, RC2, RC3 of the first surface 100. We therefore associate each construction radius RC1, RC2, RC3 of the first surface 100 with a reference radius R1, R2, R3. For each position r1, r2, r3 of the axial direction DA, the construction radius RC1, RC2, RC3 of the first surface 100 must be less than the corresponding reference radius RR1, RR2, RR3.

[0052] For each position r1, r2, r3 of the axial direction DA, the length of the circular arc formed by the first surface 100 is identical to the length L1, L2, L3 of the circular arc of body 1 associated with said position r1, r2, r3. In other words, for determining the first surface 100 of the mold, the curvilinear distances of body 1 along the circumferential direction DC are maintained. Thus, for each position r1, r2, r3 of the axial direction DA, the ratio of the construction radius RC1, RC2, RC3 to the reference radius RR1, RR2, RR3 corresponds to the transformation ratio described previously.

[0053] Thus, the first surface 100 corresponds to a curvature along the circumferential direction DC of the surface of the body to be manufactured.

[0054] We can generate a geometric model in the shape of the part to be manufactured, a first portion of the geometric model in the shape of the body to be manufactured, and a second portion of the geometric model in the shape of the flange to be manufactured. When we apply the transformation described previously to the first portion of the geometric model of the part to be manufactured, which corresponds to a curvature along the circumferential direction DC so as to decrease the radii, we obtain the first surface 100. Such a transformation of the first portion of the geometric model of the part to be manufactured will generate an inclination of the second portion of the geometric model in the shape of the flange to be manufactured, which will no longer extend along the extension direction DE but will extend along an intermediate extension direction D Pi, so as to obtain a second intermediate geometric surface 200b, as illustrated in the figure 3 .

[0055] The angle formed between the first surface 100 and the second intermediate geometric surface 200b is greater than the angle formed between the body surface and the flange surface to be manufactured. As a reminder, the angle formed between the axial direction and another direction should be understood here as the angle directed from the first surface 100 to the second intermediate geometric surface 200b, said angle being measured from the portion of the axial direction located on the side of the first surface 100 towards the second intermediate geometric surface 200b.

[0056] The second surface 200 of the mold is designed in several stages. Preferably, the second surface 200 is determined from the second intermediate geometric surface 200b. However, it does not depart from the scope of the invention if the second surface 200 is determined directly from the geometric model of the flange to be produced.

[0057] The first step consists of determining the perimeter of one or more circular arcs belonging to the flange or the second intermediate geometric surface 200b, depending on the chosen reference, said circular arcs having their center at a point belonging to the axis of revolution, as a function of their distance from the axis of revolution and the position of their center on the axis of revolution. In the example illustrated on the figures 5 et 6 said arcs of circle belong to a plane perpendicular to the axial direction.

[0058] In cases where the second surface 200 is determined directly from the geometric model of the flange to be produced, if a fillet forms the junction between the flange and the body, or if the extension direction is not perpendicular to the axial direction, it is necessary to consider the position of the center of the circular arcs belonging to the flange on the axis of revolution. The fillet forming the junction between the flange and the body is considered to be part of the flange.

[0059] In the case where the second surface 200 is determined from the second intermediate geometric surface 200b, if a fillet forms the junction between the first surface 100 and the second intermediate geometric surface 200b, or in the case where an intermediate extension direction D Pi is not perpendicular to the axial direction, it is necessary to consider the position of the center of the circular arcs belonging to the intermediate geometric surface 200b on the axis of revolution. The fillet that forms the junction between the first surface 100 and the second intermediate geometric surface 200b is considered to be part of the second intermediate geometric surface 200b.

[0060] In our illustrated example on the figures 5 et 6 , it is necessary to take into account the fillet between the first surface 100 and the second intermediate geometric surface 200b, because there is a fillet between the body 1 and the flange 2. Thus, it is necessary to determine the length of the arcs of circles belonging to the second intermediate geometric surface 200b and of arcs of circles belonging to the part of the second intermediate geometric surface 200b extending along the intermediate extension direction D Pi.

[0061] If the second surface 200 was determined directly from the geometric model of the flange to be made, we would determine the length of the arcs of circles belonging to the fillet of flange 2 and of arcs of circles belonging to the part of flange 2 extending along the extension direction DE.

[0062] We can choose several points A0, A1, A2, A3, A4, A5 belonging to the second intermediate geometric surface 200b or to flange 2, arranged at different distances from the axis of revolution A, as illustrated in the figures 5 et 6 The selected points A0, A1, A2, A3, A4, A5 preferably include a point A0 located at the junction between the first surface 100 and the second intermediate geometric surface 200b, or at the junction between the body model and the flange model 2 to be produced, as the case may be, and a point A5 located at the end of the second intermediate geometric surface 200b or the geometric model of the flange 2, as the case may be. Since a fillet is present, it is necessary to discretize the fillet. Thus, the selected points A0, A1, A2, A3, A4, A5 preferably include a point A1 located on the fillet and a point A2 located at the end of the fillet opposite the junction. Of course, choosing more or fewer points, or having a different placement, does not depart from the scope of the invention.

[0063] Each of the points A0, A1, A2, A3, A4, A5 is associated respectively with a position a0, a1, a2, a3, a4, a5 on the axis of revolution A, as illustrated in the figure 5 Each of the points A0, A1, A2, A3, A4, A5 is also associated with a circular arc including said point whose center belongs to the axis of revolution A. Thus, each of the points A0, A1, A2, A3, A4, A5 is respectively associated with a circular arc whose center has the position a0, a1, a2, a3, a4, a5. Each circular arc associated with a point A0, A1, A2, A3, A4, A5 has a length I0, I1, I2, I3, I4, I5 respectively along the circumferential direction DC.

[0064] The second step consists of determining one or more curvilinear lengths from the junction between the first surface 100 and the second intermediate geometric surface 200b, or from the junction between the geometric models of the flange and the body, as appropriate, to one or more of the arcs of the circle belonging to the second intermediate geometric surface 200b or to the flange.

[0065] If the second surface 200 is determined directly from the geometric model of the flange to be fabricated, and a sharp edge forms the junction between the flange and the body, the curvilinear lengths to be determined between the junction and the circular arcs belonging to the flange are straight lengths extending along the extension direction DE. Thus, in this configuration, the lengths from the junction are easy to determine. If a fillet forms the junction between the flange and the body, the curvilinear lengths to be determined between the junction and the circular arcs belonging to the flange are not straight.

[0066] In the case where the second surface 200 is determined from the second intermediate geometric surface 200b, if a sharp edge forms the junction between the first surface 100 and the second intermediate geometric surface 200b, the curvilinear lengths to be determined between the junction and the circular arcs belonging to the second intermediate geometric surface 200b are straight lengths extending along the intermediate extension direction D Pi. Thus, in this configuration, the lengths from the junction are easy to determine. In the case where a fillet forms the junction between the first surface 100 and the second intermediate geometric surface 200b, the curvilinear lengths to be determined between the junction and the circular arcs belonging to the second intermediate geometric surface 200b are not straight.

[0067] In our illustrated example on the figures 5 et 6 , it is necessary to take into account the fillet between the first surface 100 and the second intermediate geometric surface 200b, because there is a fillet between the body 1 and the flange 2. Thus, it is necessary to determine the curvilinear lengths between the junction and the arcs of circles belonging to the second intermediate geometric surface 200b or to the geometric model of the flange 2 as the case may be.

[0068] We take the points A0, A1, A2, A3, A4, A5 for which the associated arc lengths I0, I1, I2, I3, I4, I5 are known. By transferring the arc lengths between the points A0, A1, A2, A3, A4, A5 onto the extension direction Dp, as illustrated in the figure 6 We obtain a corresponding set of points B0, B1, B2, B3, B4, B5 separated by the curvilinear lengths e1, e2, e3, e4, e5. Thus, the curvilinear length from the junction to the arc of the circle corresponding to point A4 will be the sum of the lengths e1, e2, and e3. The total curvilinear length etotal of the second intermediate geometric surface 200b or of flange 2 from the junction to its end will therefore be the length between B0 and B5, i.e., the sum of the lengths e1, e2, e3, e4, and e5, as illustrated in the figure 6 .

[0069] Therefore, each arc length l0, l1, l2, l3, l4, l5 of circle is associated with a curvilinear length defined from the junction having respectively the value 0, e1, e1+e2, e1+e2+e3, e1+e2+e3+e4, etotal.

[0070] Generally, the first and second steps can be performed simultaneously, or one after the other in any order. At the end of the first two steps, each curvilinear length originating from the junction is associated with a circular arc length.

[0071] The third step consists of determining the geometry of the second surface 200 of the mold, which extends in the continuation of the first surface 100 of the mold along the extension direction DP.

[0072] As illustrated on the figures 7 And 8The second surface 200 is designed to exhibit undulations in the circumferential direction DC. Thus, the second surface 200 presents a plurality of circumferential undulation curves 21, 22, 23, 24, 25, one after the other, in the direction of the axial direction DA. A circumferential undulation curve comprises all points located at the same curvilinear distance from the junction between the first surface 100 and the second surface 200, said curvilinear distance belonging to the second surface 200.

[0073] The undulations of the same curve 21, 22, 23, 24, 25 have a regular period in the circumferential direction DC. The undulations of curves 21, 22, 23, 24, 25 are composed of a continuous alternation of concave and convex curves along the circumferential direction DC. The undulations of curves 21, 22, 23, 24, 25 are preferably periodic, and possibly sinusoidal or globally sinusoidal, as illustrated in the figure 8 .

[0074] The undulations of the same curve 21, 22, 23, 24, 25 exhibit a plurality of maxima and a plurality of minima. The plurality of maxima are distributed along a circle whose center lies on the axis of revolution A of the first surface 100, and the plurality of minima are distributed along a circle whose center lies on the axis of revolution A of the first surface 100. Thus, the undulations of the same curve 21, 22, 23, 24, 25 have a constant amplitude in the circumferential direction DC. The minima are defined as the points on the curves 21, 22, 23, 24, 25 closest to the axis of revolution A, and the maxima are defined as the points on the curves 21, 22, 23, 24, 25 farthest from the axis of revolution A.

[0075] The inflection points of the same curve 21, 22, 23, 24, 25 of undulations are distributed on a circle whose center belongs to the axis of revolution of the first surface.

[0076] The amplitude and number of undulations of curves 21, 22, 23, 24, 25 are chosen so as to allow the passage of the automatic fiber laying head at any point of the second surface 200. Thus, the amplitude must not be too large in order to allow the passage of said head, or to be able to lay several strands at the same time.

[0077] In the example illustrated on the figures 7 à 10 The minima of all the circumferential undulation curves are distributed on circles of identical radii, and of the same radius as the arc of a circle 20 forming the junction between the first surface 100 and the second surface 200. It is, of course, not outside the scope of the invention if the minima of all the circumferential undulation curves are distributed on circles of identical radii, but with a radius greater than the radius of the arc of a circle forming the junction between the first surface and the second surface. Nor is it outside the scope of the invention if the minima of each circumferential undulation curve are distributed on circles of different radii, provided that said radii are greater than the radius of the arc of a circle forming the junction between the first surface and the second surface.

[0078] We also do not depart from the scope of the invention if the inflection points of all the circumferential undulation curves are distributed on circles of identical radii, and of the same radius as the arc of the circle forming the junction between the first surface and the second surface.

[0079] The further one moves away from the junction between the first surface 100 and the second surface 200 in the axial direction DA, the more the circumferential undulation curves 21, 22, 23, 24, 25 progressively exhibit a large amplitude, as illustrated in the figures 7 à 10 .

[0080] The curvilinear length of each of the circumferential undulation curves 21, 22, 23, 24, 25 depends on the curvilinear distance of said circumferential undulation curve 21, 22, 23, 24, 25 from the junction between the first surface 100 and the second surface 200. Using the pairs of arc length and curvilinear length defined from the junction (l1; e1), (l2; e1 + e2), (l3; e1 + e2 + e3), (l4; e1 + e2 + e3 + e4), (l5; etotal) determined at the end of the first and second steps, we obtain that the curvilinear length of a curve 21, 22, 23, 24, 25 of circumferential undulations located at a given curvilinear distance from the junction is the length of the arc of circle l 1 , l 2 , l 3 , l 4 , l 5 previously associated with said curvilinear distance e 1 , e 1 +e 2 , e 1 +e 2 +e 3 , e 1 +e 2 +e 3 +e 4 , e total defined from the junction.

[0081] Thus the circumferential undulation curves 21, 22, 23, 24, 25 have respectively a curvilinear length l 1 , l 2 , l 3 , l 4 , l 5 when they are respectively far from the junction by a curvilinear distance e 1 , e 1 +e 2 , e 1 +e 2 +e 3 , e 1 +e 2 +e 3 +e 4 , e total .

[0082] As illustrated on the figures 9 et 10 The second surface 200 is designed to exhibit curvatures 32, 33 in the extension direction DP. Thus, the distances e1, e2, e3, e4, and etotal may not be straight lines depending on their position on the second surface 200. These curvatures 32, 33, referred to as "correction" curvatures, are necessary to limit stresses during the deformation of the draped assembly, primarily at the junction between the future body and the future flange. Indeed, if the distances e1, e2, e3, e4, and etotal were straight lines, as is the case in the previous state, the distance between the junction and the end of the second surface 200 would vary depending on its position relative to the circumferential undulations.

[0083] For example, if the minima of all the circumferential undulation curves are distributed on circles of the same radius as the arc of the circle 20 forming the junction between the first surface 100 and the second surface 200 as in our example (see figure 8 The straight-line distance between the junction and the end of the second surface 200 would be shorter in the trough of the circumferential corrugations and greater on the crest of the circumferential corrugations. Thus, at the moment of deformation of the draped assembly, there would be a shortfall in the extension direction DE at several points on flange 2, which would create stresses in the composite material of part 4.

[0084] The correction curves 32, 33 presented by the second surface 200 in the extension direction DP exhibit at least one inflection point, as illustrated on the figure 9 . The correction curves 32, 33 presented by the second surface 200 in the extension direction DP can be portions of a wave curve oscillating between a maximum and a minimum.

[0085] The second surface 200 can also include straight lengths 31, which extend from the junction towards the end of the surface 200 in the extension direction DP.

[0086] All correction curves 32, 33 and straight lengths 31 of the second surface 200 directed along the extension direction DP have an identical curvilinear length, with a total value e determined in the previous steps, as illustrated on the figure 10 . In addition, the curvilinear distance traveled by a correction curvature 32, 33 or by a straight length 31 along the extension direction DP between the junction and a curve 21, 22, 23, 24 or 25 of circumferential undulations will respectively have the value e 1 , e 1 +e 2 , e 1 +e 2 +e 3 , e 1 +e 2 +e 3 +e 4 , e total .

[0087] This yields a set of points C0, C1, C2, C3, C4, C5 located at the intersection between a straight length 31 (or a correction curve 32, 33) and each of the circumferential undulation curves 21, 22, 23, 24, 25. When the portion draped over the second surface 200 is deformed in the extension direction DE, each point in contact with a point C0, C1, C2, C3, C4, C5 will respectively be located at the position of the point A0, A1, A2, A3, A4, A5 chosen during the first or second step.

[0088] Finally, the parameters of the circumferential undulations and correction curvatures 32, 33 of the second surface 200, such as the amplitude or the radii of curvature, are chosen so as to allow the passage of the automatic fiber depositing head at any point of the second surface 200.

[0089] The design of a draping geometry described above thus makes it possible to create a suitable mold 500 for automatic fiber draping (AFP), comprising the first surface 100 and the second surface 200, as illustrated in the figure 11 The mold can be made using additive manufacturing or conventional manufacturing methods such as machining or casting. The mold may consist of several separable parts rather than a single piece, to facilitate the demolding process(es).

[0090] We will now describe in relation to the figures 12 à 15 a process for manufacturing a part from composite material comprising at least one draping step by automatic placement of fibers onto a mold designed as described above.

[0091] There figure 12 This schematically illustrates the structure of a dispensing head 6 of a device for implementing an AFP technique. The structure of the dispensing head 6 is well known. The dispensing head 6 is fed by a fibrous strip or wick 30.

[0092] The fibrous tape or wick 30 can be dry or impregnated. For example, the fibrous tape or wick 30 can be impregnated with an aqueous suspension comprising matrix precursor particles, with a thermosetting polymer, or with a thermoplastic polymer, as described in document FR3062336A1. More generally, the tape 30 can be impregnated with a resin.

[0093] The fiber strip or wick 30 can be conveyed by a conveying element 5 to a pressure application element 7 located on the side of the surfaces 100 and 200 of the draping mold. The conveying element 5 is in the form of a pair of counter-rotating rollers 5a and 5b between which the strip or wick 30 is positioned. The conveying element 5 advances the strip or wick 30 to the pressure application element 7. The pressure application element 7 applies pressure to the strip or wick 30 to deposit it onto the first and second surfaces 100 and 200 of the draping mold. The pressure application element 7 is in the form of a roller.

[0094] The dispensing head 6 may, in addition, include a heating element 9 located in the vicinity of the pressure application element 7. This heating element 9 allows, in the case of a strip or wick 30 impregnated with a thermoplastic or thermosetting polymer, the impregnated strip or wick 30 to be heated during its deposition in order to fluidize the polymer and thus give the desired adhesion power to the deposited strip or wick 30.

[0095] During deposition, the deposition head 6 is movable in order to apply the strip or strand 30 to a first defined area of ​​the draping mold, for example, to a portion of the first surface 100 of the mold. Once the application has been completed on this first area, a cutting element 11 of the deposition head 6 cuts the strip or strand 30. After this cutting, a first fibrous structure, formed by a first section of the strip or strand 30, is deposited on the first area of ​​the mold.

[0096] The formation of the blank is then continued by advancing the strip or strand 30 through the dispensing head 6 to the pressure application element 7 by actuating the conveying element 5. The dispensing head 6 can be moved to deposit the strand or strip 30 onto a second area of ​​the mold. The deposition of a second fibrous structure, formed by a second section of the strip 30, onto this second area of ​​the mold is then achieved in a manner similar to that described previously.

[0097] The creation of the rough draft is then continued by depositing several other fibrous structures in the same way as described previously, until the first surface 100 and the second surface 200 are covered.

[0098] Chemical or thermal treatments can then be carried out on the blank depending on the nature of the draped fibrous structures.

[0099] This yields a fibrous rough 4b produced by draping as illustrated in the figure 13 , comprising a body rough 1b having been draped over the first surface 100, and a flange rough 2b having been draped over the second surface 200. The body rough 1b and the flange rough 2b form the fibrous rough 4b.

[0100] The next step involves shaping the fiber blank 4b to obtain a fiber preform 4d having the shape of the part 4 to be produced and comprising a body preform 1d and a flange preform 2d. The shaping of the fiber blank 4b includes shaping the body blank 1b and shaping the flange blank 2b, which can be carried out simultaneously or one after the other.

[0101] According to a first variant, the shaping of the fibrous blank 4b includes a first intermediate shaping step of the flange blank 2b so as to obtain an intermediate flange preform 2c located in the extension of the body blank 1b and extending from the body blank 1b along the intermediate extension direction D Pi, as illustrated in the figure 14 This intermediate preform of flange 2c is obtained by a partial folding of the flange blank 2b, said folding being made possible by the undulations present on said flange blank 2b. In the first step of this first variant, the body blank 1b does not undergo any deformation.

[0102] Preferably, this variant corresponds to the case where the second mold surface 200 was determined from the second intermediate geometric surface 200b, and not directly from the geometric model of the flange 2. Thus, the intermediate flange preform 2c has the shape of the second intermediate geometric surface 200b described previously. Thanks to the particular geometry of the second surface 200 used to drape the flange blank 2b, the flange blank 2b deforms perfectly so that each undulation curve 21, 22, 23, 24, 25 becomes a circular arc with a suitable radius and so that each correction curvature 32, 33 extends in the intermediate extension direction D Pi. Thus, there are no significant stresses in the fibers of the intermediate flange preform 2c, particularly at the junction between the body blank 1b and the intermediate flange preform 2c.

[0103] In this first variant, the shaping of the fibrous blank 4b also includes a second shaping step of the body blank 1b, illustrated in the figure 15 , carried out after the first step illustrated on the figure 14 In this second step, the blank body 1b is unfolded along the circumferential direction DC to obtain the preform body 1d. The unfolding step "opens" the blank body 1b by decreasing the value of the angle intercepting the arc of the circle formed by said blank in each plane perpendicular to the axial direction DA: the angle decreases from the construction value θC until it reaches the desired reference angle θR. Furthermore, the unfolding step increases the radii of the blank body 1b along the axial direction DA from the construction values ​​RC1, RC2, RC3 until they reach the desired reference values ​​RR1, RR2, RR3. Thus, at the end of the unfolding step, the resulting preform body 1d has the same dimensions as the body 1 to be obtained.

[0104] The deployment of the body blank 1b further results in the shaping of the intermediate flange preform 2c into a flange preform 2d having the shape and geometry of the flange 2 to be obtained. Indeed, the deployment of the body blank 1b to obtain the body preform 1d causes a change in the inclination of the intermediate flange preform 2c. Thus, the intermediate flange preform 2c, extending along the intermediate extension direction D Pi from the body blank 1b before the second step, becomes, after this second step, a flange preform 2d extending along the extension direction DE from the body preform 1d.

[0105] In this first variant, an intermediate compaction step can be carried out between the first and second steps.

[0106] According to a second variant, the shaping of the fibrous rough 4b includes a first step of shaping the body rough 1b so as to obtain a preform of body 1d.

[0107] In this first step, the blank body 1b is unfolded along the circumferential direction DC to obtain the preform body 1d. The unfolding step "opens" the blank body 1b by decreasing the value of the angle intercepting the arc of the circle formed by said blank in each plane perpendicular to the axial direction DA: the angle decreases from the construction value θC until it reaches the desired reference angle θR. Furthermore, the unfolding step increases the radii of the blank body 1b along the axial direction DA from the construction values ​​RC1, RC2, RC3 until they reach the desired reference values ​​RR1, RR2, RR3. Thus, at the end of the unfolding step, the resulting preform body 1d has the same dimensions as the body 1 to be obtained.

[0108] The deployment of the body blank 1b also results in an intermediate shaping of the flange blank 2b, which yields a transitional flange preform (variant not shown). Indeed, the deployment of the body blank 1b to obtain the body preform 1d causes a change in the inclination of the flange blank 2b. Thus, the flange blank 2b, extending along the extension direction DP from the body blank 1b before the first step, becomes, after this first step, a transitional flange preform extending along a transitional extension direction from the body preform 1d.As a reminder, the angle formed between the axial direction and another direction should be understood here as the angle directed from the surface of the blank or preform of the body towards the surface of the blank or preform of the transition flange, said angle being measured from the part of the axial direction located on the side of the surface of the blank or preform of the body towards the surface of the blank or preform of the transition flange.

[0109] Preferably, this variant corresponds to the case where the second mold surface 200 was determined directly from the geometric model of the flange 2, and not from a second intermediate geometric surface 200b as described previously. Thus, the flange transition preform always exhibits the undulations described previously.

[0110] In this first variant, the shaping of the fibrous blank 4b also includes a second step of shaping the flange transition preform into a flange preform 2d. The flange preform 2d is obtained by folding the flange transition preform, this folding being made possible by the undulations present on said flange transition preform. In the second step of this second variant, the body preform 1d does not undergo any deformation.

[0111] In this second variant, an intermediate compaction step can be carried out between the first and second steps.

[0112] In the first variant and the second variant described here, carrying out the two steps separately from each other allows for better control of each step, and in particular better control of the deployment of the body blank 1b and better control of the smoothing of the undulations initially present on the flange blank 2b.

[0113] However, it may be desirable to perform the shaping of the fiber blank 4b of the part quickly, in a single step. In this third variant, the shaping of the fiber blank 4b into the fiber preform 4d of the part 4 is carried out in a single step comprising both the unfolding of the body blank 1b and the complete folding and smoothing of the undulations of the flange blank 2b.

[0114] At the end of each of the three variants described above, a 4d fibrous preform of the part to be produced is obtained, comprising the 1d body preform of body 1 to be produced and the 2d flange preform of flange 2 to be produced, as illustrated in the figure 15 Thanks to the specific geometry of the second surface 200 used to drape the flange blank 2b, the flange blank 2b deforms perfectly so that each undulation curve 21, 22, 23, 24, 25 becomes a circular arc of the flange 2 to be produced, having a suitable radius, and so that each correction curvature 32, 33 extends in the extension direction DE. Thus, there are no significant stresses in the fibers of the fibrous preform 4d, particularly at the junction between the body preform 1d and the flange preform 2d.

[0115] The deployment and shaping of the fiber blank 4b can be carried out using one or more reference mandrels having the shape of the body 1 to be produced, the flange 2 to be produced, or the desired intermediate flange preform 2c. The fiber blank is thus deployed, shaped, or smoothed to conform to the shape of the mandrel(s). The shaping of the fiber blank 4b can be carried out by mechanical deformation. The shaping of the fiber blank 4b can also be carried out using a bladder.

[0116] The resulting fibrous preform 4d can then be heat-treated to form the matrix, if this step has not already been carried out, in order to obtain the final part 4, or at least an intermediate part close to the final part 4.

[0117] If one wishes to manufacture a composite part with a complete revolution around an axis of revolution, comprising a complete body of revolution and a flange extending from one end of said body, its manufacture can be broken down by producing several sectors of said part distributed around the axis of revolution, and then assembling said sectors to obtain the desired part. Since these sectors of the part have a partial revolution, they can be produced according to the manufacturing process described previously. For example, as illustrated in the figure 16 , it is possible to manufacture two parts 4 as described previously, then assemble these two parts 4 to form a complete part of revolution 40 with axis of revolution A.

[0118] In the present application, thicknesses have been neglected for geometric considerations. If it is necessary to take into account the thickness of the part, the fiber blank, and the fiber preform, it is necessary to refer to the median surfaces and neutral lengths so that the effects of tension and compression on the upper and lower surfaces are balanced.

[0119] The expression "between ... and ..." should be understood as including the boundaries.

Claims

1. A method for determining a geometry of a draping mold (500) for producing a blank (4b) of a composite material part (4), said part (4) comprising a body (1) of partial revolution with an axis (A) directed along an axial direction (DA) and having one or more reference radii (RR1, RR2, RR3) given along said axial direction (DA), said body (1) extending partially around the axial direction (DA) along a circumferential direction (DC), and said part (4) comprising at least one flange (2) extending from one end of the body (1) along a direction of extension (DE), the method comprising: - determining a first surface (100) of revolution with an axis directed in the axial direction (DA), said first surface (100) extending around the axial direction (DA) in the circumferential direction (DC), - determining a second surface (200) located in the extension of the first surface (100) along a direction of extension (DP), the angle formed between the axial direction (DA) and the direction of extension (DP) being greater than the angle formed between the axial direction (DA) and the direction of extension (DE), the second surface (200) having corrugation curves (21, 22, 23, 24, 25) in the circumferential direction (DC) successively following each other in the direction of extension (DP), each circumferential corrugation curve (21, 22, 23, 24, 25) corresponding to a circular arc belonging to the flange (2) to be produced, the curvilinear length of said corrugation curve (21, 22, 23, 24, 25) corresponding to the length (l1, l2, l3, l4, l5) of said circular arc, the method being characterized in that the radius or radii (RC1, RC2, RC3) presented by the first surface (100) of revolution along the axial direction (DA) is / are smaller than the reference radius or radii (RR1, RR2, RR3) for the same position (r1, r2, r3) along the axial direction (DA), said first surface (100) corresponding to a curvature in the circumferential direction (DC) of a surface having the shape of the body (1) to be produced, and in that the second surface (200) has correction curvatures (32, 33) in the direction of extension (DP), so that all the points of each circumferential corrugation curve (21, 22, 23, 24, 25) are at the same curvilinear distance from the junction between the first surface (100) and the second surface (200), said curvilinear distance belonging to the second surface (200) and having a value corresponding to the curvilinear distance (e1, e1+e2, e1+e2+e3, e1+e2+e3+e4, etotal) between the circular arc belonging to the flange (2) to be produced corresponding to said circumferential corrugation curve (21, 22, 23, 24, 25), and the junction between the flange (2) and the body (1) to be produced.

2. The determination method according to claim 1, wherein the inflection points of each circumferential corrugation curve (21, 22, 23, 24, 25) are comprised in the same circle.

3. The determination method according to claim 1 or 2, wherein the minima of each circumferential corrugation curve (21, 22, 23, 24, 25) are comprised in the same circle whose radius is greater than or equal to the radius of the circular arc (20) making the junction between the first surface (100) and the second surface (200).

4. The determination method according to any one of claims 1 to 3, wherein the correction curvatures (33) located on the maxima of the circumferential corrugations have larger radii of curvature than the correction curvatures (32) located on the inflection points of the circumferential corrugations.

5. The determination method according to any one of claims 1 to 4, wherein the flange (2) to be produced comprises a fillet at its junction with the body (1) to be produced.

6. A method for manufacturing a composite material part (4) comprising a body (1) of partial revolution with an axis (A) directed along an axial direction (DA) having one or more reference radii (RR1, RR2, RR3) given along said axial direction (DA), said body (1) extending partially around the axial direction (DA) along a circumferential direction (DC), and at least one flange (2) extending from one end of the body (1) along a direction of extension (DE), the method comprising: - forming a fibrous blank (4b) of the part (4) to be obtained by depositing a plurality of fibrous plies by automatic fiber placement on a draping mold (500) comprising a first draping surface and a second draping surface located in the extension of the first draping surface, the first draping surface and the second draping surface corresponding respectively to at least the first surface (100) and the second surface (200) determined according to the method for determining a geometry of a draping mold according to any one of claims 1 to 5, the portion of the blank (4b) produced on the first draping surface corresponding to a blank of the body (1b) and the portion of the blank (4b) produced on the second draping surface corresponding to a blank of the flange (2b), - shaping the fibrous blank (4b) so as to obtain a fibrous preform (4d), said shaping comprising the deployment of the body blank (1b) in the circumferential direction (Dc) so as to obtain a body preform (1d) having the reference radius or radii (RR1, RR2, RR3) along the axial direction (DA) and having the shape of the body (1) to be produced, and shaping the flange blank (2b) so as to obtain a flange preform (2d) extending from the end of the body preform (1d) in the direction of extension (DE) and having the shape of the flange (2) to be produced, then - densifying the fibrous preform (4d) by a matrix so as to obtain the composite material part (4).

7. The manufacturing method according to claim 6, wherein the deployment of the body blank (1b) and the shaping of the flange blank (2b) are carried out simultaneously.

8. The manufacturing method according to claim 6, wherein an intermediate shaping of the flange blank (2b) is first carried out so as to obtain an intermediate flange preform (2c) extending from the end of the body blank (1b) in an intermediate direction of extension (DPi), the angle between the intermediate direction of extension (DPi) and the axial direction (DA) being smaller than the angle between the direction of extension (DP) and the axial direction (DA) but greater than the angle between the direction of extension (DE) and the axial direction (DA), then the deployment of the body blank is carried out so as to obtain the body preform and so as to carry out the shaping of the intermediate flange preform (2c) in order to obtain the flange preform (2d) extending from the end of the body preform (1d) in the direction of extension (DE) and having the shape of the flange (2) to be produced.

9. A method for manufacturing a composite material part (40) comprising a body of complete revolution with an axis (A) directed along an axial direction having one or more given reference radii, said body extending partially around the axial direction along a circumferential direction, and at least one flange extending from one end of the body along a direction of extension, the method comprising: - producing part sectors (4) comprising a body sector (1) of partial revolution with an axis directed along an axial direction having the given reference radius, said body sector (1) extending partially around the axial direction along a circumferential direction, and at least one flange sector (2) extending from one end of the body sector (1) along a direction of extension, the manufacturing of said part sectors (4) being carried out according to the manufacturing method of any one of claims 6 to 8, - assembling the part sectors (4) to obtain the composite material part (40) having a complete revolution.