Additive manufacturing process for an aeronautical part

Abstract

Additive manufacturing method for an aeronautical part. One aspect of the invention relates to a method for additive manufacturing of a part by an additive manufacturing machine comprising: Commanding the machine to manufacture a first part, according to an initial digital representation of the part; Determining a first digital representation of the part from a back-deformation of the initial digital manufacturing representation with respect to a first experimental representation, the first experimental representation corresponding to the first part manufactured; Commanding the machine to manufacture a second part, according to the first digital representation; Determining a back-deformation error from a deviation of a second experimental representation with respect to the initial digital manufacturing representation, the second experimental representation corresponding to the second part manufactured;Determine a second digital representation of the part from a counter-deformation of the first digital representation with respect to the counter-deformation error; Command the machine to manufacture the part, according to the second digital representation of the part.

Description

Title of the invention: Additive manufacturing process for an aeronautical part. TECHNICAL FIELD OF THE INVENTION

[0001] The technical field of the invention is that of the manufacture of parts, in particular parts of an aircraft by additive manufacturing.

[0002] The present invention relates to a method for the additive manufacturing of a part. TECHNOLOGICAL BACKGROUND OF THE INVENTION

[0003] The high-pressure turbine blades of an aircraft engine, such as an airplane or a helicopter, are complex parts (i.e., comprising many small cavities, in particular cores) which must withstand, when the engine in question is in operation, temperatures higher than the melting point of the metal which composes them as well as extreme mechanical stresses.

[0004] To withstand these constraints, a three-level cooling system is implemented: • One or more cores allow for internal cooling of the blade; • A series of perforations allows the formation of a cold film around the room; • A material designed to withstand high thermomechanical stresses and to resist the aggressive environment of the turbine.

[0005] The development of new blades therefore aims to design these three elements in such a way as, on the one hand, to improve their cooling performance to dissipate the temperature rise generated by the operation of the engine and, on the other hand, to increase the mechanical resistance of the blades to the strong mechanical stresses they undergo.

[0006] To this end, these newly developed parts are increasingly complex. The increased complexity of the cooling circuits involves, in particular, reducing the size of the core cavities and increasing their number. This allows for localized cooling of the turbine blades, while maintaining a geometry with good mechanical strength.

[0007] One of the drawbacks of these complex parts is that their manufacture requires the use of manufacturing processes that introduce deformations into the parts, potentially at all stages of their production (including cleaning, debinding, sintering, etc.), which is typically the case with additive manufacturing. These deformations make the geometry of the manufactured parts non-conform to the designs that were created.

[0008] Furthermore, anticipating these deformations at the design stage is difficult because the manufacturing variability of a part is very complex, therefore difficult to predict, and cannot be perfectly simulated. Geometric deviations during the initial manufacturing process are thus often greater than the acceptability criteria set by the specifications for that part.

[0009] To compensate for this deformation, it is known to counter-deform the initial manufacturing geometry of the object so that it is closer to the desired geometry, based on the shape of the first parts produced. However, this deformed manufacturing geometry leads to a modification of the printed geometry, manifesting itself, for example, as wall thinning, surface irregularities, significant geometric deviations, etc. The behavior of the deformed part is then different from that of the part initially designed, both during manufacturing and after the deformed part has been produced.

[0010] The commonly used approach then consists of iteratively modifying the geometry of the part, through back-and-forth between the design office and the manufacturer, in order to gradually move towards a conforming part despite manufacturing variations. The drawback is that the number of iterations required to manufacture a conforming part is large and increases with the complexity of the parts.

[0011] Moreover, these successive iterations frequently generate defects, particularly new deformations, as mentioned above, which were not present in previous iterations, notably because the deformations of a part depend on its geometry: when this geometry changes from one iteration to another, the deformations are not the same and, as indicated previously, cannot easily be predicted. It then appears that the part thus manufactured is of inferior quality to that initially designed.

[0012] There is therefore a need for a means of manufacturing a part which makes it possible to quickly obtain a part conforming to its specifications, while taking into account the constraints related to manufacturing, in particular the deformations induced by the manufacturing process. Summary of the invention

[0013] The invention offers a solution to the problems mentioned above, by making it possible to produce a corrected model of the part to be manufactured, obtained both by taking into account the initially designed model of the part and an error induced by a model introducing a counter-deformation of the part to compensate for the deformations generated during manufacturing.

[0014] A first aspect of the invention relates to a computer-implemented method for the additive manufacturing of a part by a machine, the machine being of a given additive manufacturing machine model, the method comprising: • Command the machine to manufacture a first part, according to an initial digital representation of the part's manufacture; • Determine a first digital representation of the part from a counter-deformation of the initial digital manufacturing representation with respect to a first experimental representation, the first experimental representation corresponding to the first part manufactured; • Order the machine to manufacture a second part, according to the first digital representation; • Determine a back-deformation error from a deviation of a second experimental representation from the initial digital manufacturing representation, the second experimental representation corresponding to the second manufactured part; • Determine a second digital representation of the part from a counter-deformation of the first digital representation with respect to the counter-deformation error; • Order the machine to manufacture the part, according to the second digital representation of the part.

[0015] The machine used to manufacture the different parts can be the same machine or a machine of the same model.

[0016] The term "digital representation" refers to a model in digital form of one or more geometric properties of the part under consideration. In particular, it refers to a property of the geometry, for example, internal and / or external, of the part. By way of example, the digital representation is a model of the part, more specifically of the geometry, for example, internal and / or external, of the part, for example in the form of a mesh. The mesh, formed of nodes, defines the geometry of the part in a discrete manner. The nodes of the mesh delimit elements of finite dimensions. The internal geometry of the part includes, for example, the geometry of cavities manufactured within the part.

[0017] The term "counter-deformation" refers to a modification of a digital representation, that is, a modification of the model of the part in question, so as to compensate for a deformation induced by the manufacturing of the part according to said model of the part. In other words, counter-deformation is a correction of the manufacturing model in order to compensate for deformations appearing during the manufacturing of the part. A manufacturing deformation may, in particular, be induced by the machine or the machine model, by the manufacturing process itself, or by the properties of the material of the manufactured part, etc., and is dependent, in particular, on the geometry of the part.

[0018] The term "counter-deformation error" refers to an anomaly in a property of the part, particularly its geometry, which results from the counter-deformation applied to the initial digital manufacturing representation, i.e., the initial manufacturing model, and carried by the first digital representation. The counter-deformation error thus quantifies the deformation of the manufactured part after the application of the counter-deformation. In other words, the counter-deformation error represents the manufacturing error of the second manufactured part relative to the first digital representation, the latter including a counter-deformation of the initial manufacturing model to compensate for the deformation of the first part relative to the initial manufacturing model.

[0019] Thanks to the invention, it is possible to calculate in a deterministic manner the deformation to be applied to the initial manufacturing representation of the part so that the resulting part, after manufacturing, conforms to the desired geometry.

[0020] Indeed, on the one hand, the proposed method makes it possible to compensate for the deformations induced by the manufacturing of the part, via counter-deformations applied to the initial digital manufacturing representation, these counter-deformations being included in the first digital representation. On the other hand, the proposed method makes it possible to correct, via the second digital representation, the geometric anomalies induced by these counter-deformations, since the second digital representation is constructed by counter-deformation of the first digital representation, taking into account the deformation error generated by the counter-deformations of this first digital representation.

[0021] The invention therefore makes it possible to correct the new deformations caused by the counter-deformations of the initial manufacturing model, while preserving the modifications already made to the original geometry and included in the first digital representation.

[0022] In other words, the idea here is to provide the manufacturing machine with a "false" geometry, compared to the initial geometry, in order to obtain a part whose geometry is identical or almost identical to the desired geometry, included in the initial model.

[0023] The proposed method thus makes it possible to quantify the deformations induced by the manufacturing of the part in order to compensate for them, in a few iterations, so as to produce the desired part as if the manufacturing process were perfect or almost perfect, that is to say, as if the manufacturing process did not generate these deformations. The proposed method therefore makes it possible to obtain a final part that conforms to the initial manufacturing model.

[0024] The term "the corrected part conforms to the initial manufacturing model" means that the geometry of the corrected part meets predefined tolerances, in particular those specified in the specifications, indicating an authorized variability in geometry for the part produced, compared to its initial manufacturing model.

[0025] In particular, the invention makes it possible to eliminate deformations and counter-deformations only in the areas of the part affected by them. This reduces the time required to design the conforming part without altering the areas of the part that are not affected by deformations.

[0026] Furthermore, each manufacturing process can be carried out by any machine of the same model, since the deformations appearing during manufacturing are primarily dependent on the machine technology and not on the machine itself. In other words, when the part is manufactured according to the second digital representation, for example in series, by several machines of the same model, the parts thus manufactured conform to the initial digital manufacturing representation and exhibit small deviations in properties, particularly in geometry, from one another.

[0027] In addition to the characteristics just mentioned, the method according to the first aspect of the invention may have one or more complementary characteristics from among the following, considered individually or according to all technically possible combinations.

[0028] In one embodiment, the initial manufacturing digital representation includes a mesh of an ideal geometry, for example internal and / or external, of the part, the first experimental representation includes a mesh of a geometry, for example internal and / or external, of the first part, the first digital representation includes a mesh of a counter-deformed geometry, for example internal and / or external, of the first part, the second experimental representation includes a mesh of a geometry, for example internal and / or external, of the second part, and the second digital representation includes a mesh of a corrected geometry, for example internal and / or external, of the part.

[0029] The term “ideal geometry of the part” means a geometry of the part specifically designed to meet the needs and requirements of the part specification.

[0030] The term "corrected geometry of the part" means a geometry of the part specifically designed to compensate for the deformation of the counter-deformation appearing during the manufacture of the second part, i.e., manufactured according to the second digital representation.

[0031] In one embodiment, the first experimental representation is determined at the end of the manufacture of the first part and the second experimental representation is determined at the end of the manufacture of the second part.

[0032] These two numerical representations are thus determined when the part has reached thermodynamic equilibrium, allowing for the reproducibility of the proposed method. For example, these two numerical representations are determined when the pressure and temperature conditions of the part have reached ambient pressure and temperature conditions, corresponding to a temperature between 15°C and 25°C and a pressure between 0.9 and 1.1 bar. The end of manufacturing therefore corresponds to the point at which the geometry of the part will no longer change, for example, due to the cooling of the part as it exits the manufacturing machine (including before debinding and / or sintering of the filled binders used in manufacturing), or even after any possible treatment or rectification of the part (for example, after heat treatment for rectification, after debinding and / or sintering, etc.).

[0033] In one embodiment, the first experimental representation and the second experimental representation are determined via non-destructive testing.

[0034] In one embodiment, non-destructive testing is X-ray tomography testing, surface optical measurement testing or a three-dimensional measurement method.

[0035] Typically, X-ray tomography allows the external and internal geometry of the part to be determined, while control by surface optical measurement or a three-dimensional measurement method allows only the external geometry of the part to be determined.

[0036] In one embodiment, the part is a cooling core for a high-pressure turbine blade of an aircraft.

[0037] A second aspect of the invention relates to a system for manufacturing a part by a machine, the machine being of a given machine model, the system being configured to implement the steps of the method according to the first aspect.

[0038] A third aspect of the invention relates to a computer program product comprising instructions which, when the program is executed on a computer, lead the latter to implement the steps of the method according to the first aspect.

[0039] Another aspect of the invention relates to a computer-readable recording medium comprising instructions which, when executed by a computer, lead the computer to implement the steps of the method according to the second aspect.

[0040] The invention and its various applications will be better understood by reading the following description and examining the accompanying figures. BRIEF DESCRIPTION OF THE FIGURES

[0041] The figures are presented for illustrative purposes only and are in no way limiting of the invention. • The [Fig. 1] is a synoptic diagram illustrating the sequence of steps of a method according to an embodiment of the invention. • Fig. 2 is a representation of the implementation of the method according to one embodiment of the invention. DETAILED DESCRIPTION

[0042] Unless otherwise specified, the same element appearing on different figures has a unique reference.

[0043] The manufacturing of parts leads to the appearance of deformations of the properties of the part with respect to the initially designed model of this part, in particular its geometry, for example the internal and / or external geometry, during its manufacture.

[0044] This is the case, for example, when the part is manufactured by an additive manufacturing machine. The advantage of using such a machine is that it allows the production of parts with complex geometries, particularly aircraft blades, for example, high-pressure turbine blades, or cooling cores for these blades. Indeed, it is not possible to use injection molding processes for these parts because their complexity results in geometries that are so-called "non-demoldable," meaning that the manufactured parts cannot be removed from their injection molds.

[0045] The drawback of using such an additive manufacturing machine is that the geometries of the manufactured parts do not conform to the geometries designed for their manufacture. Indeed, the manufacture of such parts generates deformations, in this case deformations of the geometry, for example internal and / or external, of these parts, related both to the manufacturing process itself and to the material used for manufacturing and / or the machine model.

[0046] It is known to counter-deform the designed manufacturing geometry in order to compensate for these deformations, but this generates new defects on the geometry of the new manufactured part.

[0047] In this respect, the invention proposes a method for compensating for these deformations by determining a deformation error of the part. This error corresponds to a difference between a part manufactured after compensation of a counter-deformation and an initial manufacturing model, including in particular the ideal geometry of the part. This error is then used to determine a corrected model of the part in order to produce the part corresponding to the initial model as if the manufacturing process had not generated, or had generated almost no, deformations. The corrected model is therefore a digital representation an error in the part but which allows a part to be manufactured conforming to the initial manufacturing model.

[0048] One aspect of the invention therefore relates to a method, implemented by a computer, for manufacturing a part. The part is, for example, an aircraft blade, such as a high-pressure turbine blade, or a cooling core of an aircraft blade, in particular a cooling core of a high-pressure turbine blade.

[0049] The implementation of method 100 is jointly illustrated in figures 1 and 2.

[0050] The part, labeled "Final Part" in [Fig. 2], is manufactured, via method 100, by a machine of a given machine model. The part can therefore be manufactured by any machine of that machine model.

[0051] Method 100 includes a step 110 of controlling the machine, or a machine of the same machine model, i.e., of the given machine model, to manufacture a first part, marked "Part 1" on the [Fig.2].

[0052] The first part is manufactured according to an initial digital representation of the part manufacturing, noted as "Initial Model" on [Fig.2].

[0053] The term "manufactured according to a representation" means that the machine produces the part as defined in the corresponding digital representation, here the initial digital manufacturing representation. The initial digital manufacturing representation, also called the initial manufacturing model, is therefore a digital model of the part to be manufactured and includes one or more geometric properties of this part, for example, its geometry (e.g., internal and / or external), which is then the desired geometry, called the ideal geometry (e.g., internal and / or external), for the part to be manufactured. Once manufactured via method 100, the desired part must therefore conform to the geometric properties included in the initial digital manufacturing representation, in particular to the ideal geometry.

[0054] The geometric properties of the part, in the initial digital manufacturing representation, are, for example, defined by a design office and / or an operator using the method, so as to comply with constraints imposed by the part's specifications, particularly regarding its composition, geometry, manufacturing, and / or use. The geometric properties of the part included in the initial digital manufacturing representation are therefore the desired geometric properties for that part to be manufactured.

[0055] The initial digital representation of the manufacturing process is thus, for example, predetermined by the design office and / or by the operator, for example via a simulation tool, such as a computer-aided design (CAD) tool. By "predetermined" it is understood that the initial digital representation is established before the implementation of method 100.

[0056] The initial digital representation is, for example, contained in a computer file, which is stored in the computer's memory. The computer file is preferably in a format readable and / or interpretable by the manufacturing machine so as to produce the first part directly by reading and / or interpreting this file. The computer file is also in a format readable and / or interpretable by the computer.

[0057] With reference to [Fig.2], step 110 therefore allows the manufacturing of Part 1 to be triggered from the initial Model.

[0058] Method 100 also includes a step 130 of determining a first digital representation of the part, i.e., the part to be manufactured by method 100. This first digital representation, labeled "Model 1" in [Fig. 2], is determined from the initial manufacturing representation to which at least one counter-deformation is applied. This counter-deformation serves to compensate for one or more deformations of the first part, for example, of its geometry (e.g., internal and / or external), caused by the manufacturing of this first part.

[0059] The first digital representation of the part, also called the first manufacturing model, is therefore determined from the counter-deformation of the initial digital manufacturing representation, with respect to a first experimental representation. The first experimental representation corresponds to a digital representation of the first part, that is, the part produced from the initial digital representation. Due to the deformation, one or more geometric properties of the first manufactured part, in particular its geometry (for example, internal and / or external), differ from the geometric properties included in the initial digital representation.

[0060] The first experimental representation, labeled "Experimental Model 1" in [Fig. 2], is determined using any technique known per se for determining the geometric properties of the first part, in particular its geometry (e.g., internal and / or external). The first experimental representation, also called the first experimental model, includes these measured geometric properties of the first part, in particular the geometry, e.g., internal and / or external, of the first part, and is in the same format as the initial digital manufacturing representation.

[0061] The first digital representation, determined by the counter-deformation of the initial digital representation with respect to the first experimental representation, is determined by any technique known in itself, allowing the determination and application of the counter-deformation to be applied to counter-deform the initial digital representation according to the first experimental model.

[0062] In particular, the counter-deformation thus determined can be a counter-deformation of the geometry (for example internal and / or external) of the part, called the counter-deformed geometry (for example internal and / or external), with respect to the ideal geometry.

[0063] The first digital representation therefore corresponds to the counter-deformation of the initial digital manufacturing representation.

[0064] Method 100 also includes a step 140 of controlling the machine, or a machine of the same machine model, i.e., of the given machine model, to manufacture a second part, marked "Part 2" on the [Fig.2].

[0065] The second part is manufactured according to the first digital representation. The first digital representation is, for example, contained in a computer file, which is stored in the computer's memory once the first digital representation is determined. For instance, the file containing the first digital representation is saved, that is, written, to the computer's memory after this first digital representation has been determined. This computer file is preferably in a format readable and / or interpretable by the manufacturing machine so that the second part can be produced directly by reading and / or interpreting this file. This computer file is also in a format readable and / or interpretable by the computer.

[0066] With reference to [Fig.2], step 140 therefore allows the manufacturing of Part 2 from Model 1 to be triggered.

[0067] Method 100 also includes a step 160 for determining a back-deformation error. This back-deformation error, labeled "Back-deformation error" in [Fig. 2], corresponds to a difference between the second manufactured part and the initial digital manufacturing representation. In particular, this error is determined from a difference between a second experimental representation and the initial digital manufacturing representation.

[0068] The second experimental representation, labeled “Experimental Model 2” in [Fig. 2], corresponds to the second manufactured part. The second experimental representation, also called the second experimental model, is determined in a manner analogous to the determination of the first experimental representation. The second experimental representation therefore includes the geometric properties measured on the second part, in particular the geometry (e.g., internal and / or external) of the second part, and is in the same format as the initial digital manufacturing representation.

[0069] The back-deformation error is determined by any technique known per se for determining a gap or distance between two digital representations (which are, for example, in the form of meshes), for example under the form of a difference, a quadratic deviation, or any other type of deviation. For example, when the digital representations are in the form of a mesh of the geometry (e.g., internal and / or external) of the corresponding part, the deviation or distance is a difference, or a distance, between the respective meshes of the digital representations considered.

[0070] In particular, the counter-deformation error may correspond to a discrepancy between the geometry of the second part included in the second experimental representation and the desired geometry included in the initial digital manufacturing representation.

[0071] The counter-deformation error therefore corresponds to the error on the geometric property or properties of the second part which are considered, with respect to the initial model, which originate from the counter-deformation applied to the initial model, which is included in the first numerical representation.

[0072] Method 100 also includes a step 170 of determining a second digital representation of the part, i.e., the part to be manufactured by Method 100. This second digital representation, labeled "Model 2" in [Fig. 2], is determined from the first digital representation, to which at least one counter-deformation is applied, and from the counter-deformation error. This counter-deformation applied to the first digital representation serves to compensate for a manufacturing error related to the counter-deformation included in the first digital representation.

[0073] The second digital representation is determined by any technique known per se, allowing the determination and application of the counter-deformation to be applied to counter-deform the first digital representation as a function of the counter-deformation error. The technique employed may be the same as that used to determine the first digital representation.

[0074] The second digital representation, otherwise called the second manufacturing model, therefore corresponds to a digital format representation of the part to be manufactured via method 100, i.e. of the part to be produced, and whose geometric properties must conform to the geometric properties of the initial digital manufacturing representation.

[0075] By way of example, the second digital representation is determined by applying a counter-deformation to the first digital representation, in particular to its geometry (for example, internal and / or external), for one or more portions of the second part for which there is a counter-deformation error. The second digital representation therefore includes the counter-deformation of the counter-deformation included in the first digital representation.

[0076] In particular, the second digital representation includes the counter-deformation of the geometry (for example internal and / or external) being counter-deformed (the latter being included in the first digital representation), and called the geometry (for example internal and / or external) corrected of the part to be manufactured, to compensate for the counter-deformation applied to the initial digital manufacturing representation.

[0077] Method 100 also includes a step 180 of controlling the machine, or a machine of the same machine model, i.e., of the given machine model, to manufacture the part, i.e., the final part of [Fig.2].

[0078] The said part is manufactured according to the second digital representation. This part thus manufactured conforms to the initial digital manufacturing representation, since the geometric errors induced by the counter-deformation included in the first digital representation have been compensated, i.e., have been corrected, in the second digital representation, via another counter-deformation.

[0079] The second digital representation is, for example, contained in a computer file, which is stored in the computer's memory once the second digital representation has been determined. For example, the file containing the second digital representation is saved, that is, written, to the computer's memory after this second digital representation has been determined. This computer file is preferably in a format readable and / or interpretable by the manufacturing machine so as to produce the part directly by reading and / or interpreting this file. This computer file is also in a format readable and / or interpretable by the computer.

[0080] With reference to [Fig.2], step 180 therefore allows the manufacturing of the final Part to be triggered from Model 2.

[0081] The invention thus allows for a significant time saving compared to known methods, by preserving the counter-deformations during the establishment of the second digital representation, rather than performing iterative loops between the manufacturing geometry and the actual geometry, which introduces significant errors in correcting these geometries. Indeed, by preserving the already calculated deformations, the invention makes it possible to manufacture the desired part with unprecedented geometric precision, particularly for the additive manufacturing of turbine blades.

[0082] This invention can advantageously be used for all parts, for all types of materials (ceramic, metal, polymer, etc.), and all geometries of parts produced by additive manufacturing (including for indirect additive manufacturing, i.e., via the manufacture of a sacrificial injection mold by polymer additive manufacturing), regardless of the industrial field (automotive, aeronautical, railway, nuclear, etc.).

[0083] It can be appreciated that it is entirely possible to repeat steps 160 for determining the back-deformation error, 170 for determining the second digital representation, and 180 for manufacturing the second part. Indeed, it is possible that residual errors may remain despite the implementation of method 100. In this case, step 160 makes it possible to determine a back-deformation error between the second digital representation and a third experimental representation (i.e., a third experimental model), which corresponds to the part manufactured at the end of step 180, then called the third part, according to the second digital representation, and determined in a similar way to the first and second experimental representations. Repeating step 170 then makes it possible to determine a third digital representation (i.e.a third manufacturing model), in a manner analogous to the determination of the second digital representation, but based on the newly calculated back-deformation error and the second digital representation. Finally, the new implementation of step 180 allows the part to be manufactured according to the third digital representation. If necessary, it is also possible to repeat these steps.

[0084] In one embodiment, the machine model is an additive manufacturing machine model or a lost-wax casting machine model. The machine is therefore an additive manufacturing machine or a lost-wax casting machine.

[0085] In an embodiment compatible with the previous embodiment: • The initial digital manufacturing representation includes a mesh corresponding to the ideal geometry, for example internal and / or external, of the part; • The first experimental representation includes a mesh corresponding to the geometry, for example internal and / or external, of the first part; • The first digital representation includes a mesh corresponding to the geometry, for example internal and / or external, counter-deformed of the first part; • The second experimental representation includes a mesh corresponding to the geometry, for example internal and / or external, of the second part; and • The second digital representation includes a mesh corresponding to the corrected geometry, for example internal and / or external, of the part.

[0086] In one embodiment, compatible with the preceding embodiments, the first experimental representation is determined at the end of the manufacturing process The experimental representation of the first part and the second experimental representation is determined at the end of the manufacturing of the first part. In particular, these experimental representations are determined once their corresponding part has reached ambient temperature and pressure, typically between 15°C and 25°C and between 0.9 and 1.1 bar, respectively.

[0087] In an embodiment compatible with the preceding embodiments, the first experimental representation and the second experimental representation are determined via non-destructive testing, typically by a technique known per se. For example, these experimental representations are determined by X-ray tomography, by surface optical measurement, or by a three-dimensional measurement method.

[0088] In an embodiment compatible with the preceding embodiments, method 100 includes a step 105 of obtaining the initial digital manufacturing representation, i.e., the initial model used to manufacture the part and which may include the ideal geometry (e.g., internal and / or external). The initial digital representation can be obtained by any known technique and can come from any source capable of producing and / or transmitting this initial digital representation.

[0089] In an embodiment compatible with the preceding embodiments, the first digital representation comprises a first plurality of portions. Each portion corresponds to one of the parts of the part to be manufactured according to the first digital representation. In particular, each portion of the first plurality of portions corresponds to a part of the geometry (for example, internal and / or external) of the part to be manufactured according to this first digital representation, specifically to a part of the surface (for example, internal and / or external) of this part.

[0090] Similarly, the second experimental representation comprises a second plurality of portions. Each portion corresponds to one of the parts of the second piece. In particular, each portion of the second plurality of portions corresponds to a part of the geometry (for example, internal and / or external) of the second piece, specifically to a part of the surface (for example, internal and / or external) of this second piece.

[0091] Each portion of the first plurality of portions corresponds to at least one portion of the second plurality of portions. Similarly, each portion of the second plurality of portions corresponds to at least one portion of the first plurality of portions.

[0092] In this embodiment, the back-deformation error, determined in step 160, is determined for each portion of the second experimental representation, with respect to the corresponding portions of the first representation numerical. For each portion of the second plurality of portions, a distance is thus obtained between the geometry of the second part and the model on which its manufacture was based. The counter-deformation error can therefore be different for one or more portions or for each portion of the second plurality of portions.

[0093] In this embodiment, the counter-deformation applied in step 170, which aims to determine the second digital representation, is applied to the portions of the first plurality of portions for which the corresponding portions of the second plurality of portions have a counter-deformation error exceeding a predefined threshold. In other words, the counter-deformation is applied to the first manufacturing model only where the counter-deformation error is greater than a tolerance set by the predefined threshold.

[0094] The predefined threshold is, for example, predetermined by the operator or the design office, either automatically via a dedicated application or manually, for example based on knowledge relating to the manufacturing of the part and / or the part specifications. The threshold is therefore established before the implementation of step 170, which determines the second digital representation.

[0095] By way of example, the predefined threshold is between 5 pm and 1 mm, for example between 10 pm and 100 pm, typically between 15 pm and 50 pm, for example equal to 20 pm.

[0096] The predefined threshold may be the same for all portions of the second experimental representation or be different for one, several or all portions.

[0097] In one embodiment, the first digital representation comprises a first mesh corresponding to the geometry (e.g., internal and / or external) of the part to be manufactured according to this first digital representation. Similarly, the second experimental representation comprises a second mesh corresponding to the geometry (e.g., internal and / or external) of the second part. The first mesh comprises a first set of nodes, forming a first set of elements, and the second mesh comprises a second set of nodes, forming a second set of elements.

[0098] In this embodiment, each portion of the first plurality of portions corresponds to several nodes of the first set of nodes and / or to one or more elements of the first set of elements, these nodes and / or elements being contiguous or disjoint. Similarly, each portion of the second plurality of portions corresponds to several nodes of the second set of nodes and / or to one or more elements of the second set of elements, these nodes and / or elements being contiguous or disjoint. The back-deformation error is then determined for these sets of nodes and / or elements, and the back-deformation compensation included in the first manufacturing model is carried out for the sets of nodes and / or elements corresponding to the portions for which the counter-deformation error is greater than the predefined threshold.

[0099] In an embodiment compatible with previous embodiments, the counter-deformation applied in step 130, aimed at determining the first digital representation, and the counter-deformation applied in step 170, aimed at determining the second digital representation, are determined via VGSTUDIO MAX™ software, AVIZO™ software, Z-SET™ software, or any other software or approach known to determine a counter-deformation.

[0100] Another aspect of the invention relates to a system for manufacturing the part by the machine. In this case, the system is configured to implement the steps of method 100.

[0101] In particular, the system may include a computing unit, for example a computer, which includes a processor and volatile or non-volatile memory. Instructions are stored in said memory and, when these instructions are executed by the processor, they lead to the implementation of the steps of method 100.

[0102] The system is connected to the machine and / or to a machine of the same model. "Connected" means that there is a medium, whether physical or non-physical, enabling the transmission of data from the system to the machine. This medium is, for example, a wired or wireless connection.

[0103] In one embodiment, the system includes the machine and / or the machine of the same model, used to manufacture the first part, the second part and / or the final part, i.e. the part to be manufactured via method 100.

[0104] The machine is connected to the system computer.

[0105] In this embodiment, method 100 may also include: • A step 115 in the manufacturing of the first part; • A step 145 in the manufacturing of the second part; and / or • Step 185 of the part manufacturing process.

[0106] In an embodiment compatible with the preceding embodiment, the system also includes a measuring device configured to measure the geometric properties, in particular the geometry, for example internal and / or external, of the first part and / or the second part. This device is, for example, a non-destructive testing device using X-ray tomography, surface optical measurement, or a three-dimensional measurement method.

[0107] This measuring device is connected to the system computer.

[0108] In this embodiment, method 100 may further comprise: A step 120 of determining the first experimental representation; and / or A step 150 of determining the second experimental representation.

Claims

Demands

1. A computer-implemented method (100) for additively manufacturing a part by a machine, the machine being of a given additive manufacturing machine model, the method comprising: - Commanding (110) the machine to manufacture a first part, according to an initial digital representation of the part's manufacture; - Determining (130) a first digital representation of the part from a counter-deformation of the initial digital representation of the manufacture with respect to a first experimental representation, the first experimental representation corresponding to the first part manufactured; - Commanding (140) the machine to manufacture a second part, according to the first digital representation;- Determine (160) a back-deformation error from a deviation of a second experimental representation from the initial digital manufacturing representation, the second experimental representation corresponding to the second part manufactured; - Determine (170) a second digital representation of the part from a back-deformation of the first digital representation with respect to the back-deformation error; - Command (180) the machine to manufacture the part, according to the second digital representation of the part.

2. Method (100) according to the preceding claim, wherein the initial manufacturing digital representation comprises a mesh of an ideal geometry of the part, the first experimental representation comprises a mesh of a geometry of the first part, the first digital representation comprises a mesh of a counter-deformed external geometry of the first part, the second experimental representation comprises a mesh of an external geometry of the second part, and the second digital representation comprises a mesh of a corrected external geometry of the part.

3. Method (100) according to any one of the preceding claims, wherein the first experimental representation is determined at the end of the manufacture of the first part and the second experimental representation is determined at the end of the manufacture of the second part.

4. Method (100) according to any one of the preceding claims, wherein the first experimental representation and the second experimental representation are determined via non-destructive testing.

5. Method (100) according to claim 4, wherein the non-destructive testing is an X-ray tomography test, an optical surface measurement test or a three-dimensional measurement method.

6. Method (100) according to any one of claims 1 to 5, wherein the part is a cooling core of a high-pressure turbine blade of an aircraft.

7. System for manufacturing a part by a machine, the machine being of a given machine model, the system being configured to implement the steps of method (100) according to any one of the preceding claims.

8. Computer program product comprising instructions which, when the program is executed on a computer, cause the computer to carry out the steps of the method (100) according to any one of claims 1 to 6.

9. A computer-readable recording medium comprising instructions which, when executed by a computer, cause the computer to carry out the steps of the method (100) according to any one of claims 1 to 6.

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