Turbomachine blade with an electrical de-icing conductor and associated manufacturing method

Abstract

The invention proposes a turbomachine blade (9; 109; 209) that is noteworthy in that it comprises an electrical conductor (32) entirely covered with metal material formed by cold gas dynamic spraying of a metal powder. The invention also relates to a method for manufacturing a turbomachine blade, the method comprising: manufacturing a body by forging, casting, machining and / or additive manufacturing; placing or depositing an electrical conductor on the body; and covering the electrical conductor by cold gas dynamic spaying of a metal powder. The invention also proposes a turbomachine compressor comprising a blade that is noteworthy in that the blade is according to the invention or manufactured according to the method of the invention.

Description

TURBOMACHINE BLADE WITH ELECTRIC DE-ICING CONDUCTOR AND ASSOCIATED MANUFACTURING METHOD

[0001] The invention relates to de-icing systems for turbomachine blades. Prior art

[0002] Climate change is a major concern for many legislative and regulatory bodies around the world. Indeed, various carbon emission restrictions have been, are being, or will be adopted by various states. In particular, an ambitious standard applies to both new aircraft types and those already in operation, requiring the implementation of technological solutions to ensure their compliance with current regulations. Civil aviation has been mobilizing for several years now to contribute to the fight against climate change.

[0003] Technological research efforts have already led to very significant improvements in the environmental performance of aircraft. The Applicant takes into consideration the impact factors in all phases of design and development to obtain less energy-intensive, more environmentally friendly aeronautical components and products whose integration and use in civil aviation have moderate environmental consequences with the aim of improving the energy efficiency of aircraft.

[0004] Consequently, the Applicant is constantly working to reduce its negative climate impact by using methods and operating virtuous development and manufacturing processes and minimizing greenhouse gas emissions to the minimum possible in order to reduce the environmental footprint of its activity.

[0005] This sustained research and development work focuses on new generations of aircraft engines, the weight reduction of aircraft, particularly through the materials used and lighter on-board equipment, the development of the use of electrical technologies to ensure propulsion, and, as an essential complement to technological progress, aeronautical biofuels.

[0006] In this context, the invention relates more particularly to the aspects related to the efficiency and safety of aircraft turbomachine compressors. Indeed, within the primary vein and at the inlet of the low-pressure compressor (also commonly called "booster") there is a set of straightening stator vanes (also called IGV for "Inlet Guide Vane").

[0007] In certain phases of flight and on the ground, atmospheric conditions may be encountered that are conducive to the formation of frost or ice on the straightening vanes. When this phenomenon occurs, it can lead to partial or total obstruction of the primary flow path, and to the ingestion of detached blocks of ice into the primary flow path. Indeed, an obstruction of the primary flow path results in underfeeding of the combustion chamber, which can then shut down or prevent acceleration of the turbomachine.

[0008] Published patent document EP 3 228 834 A1 discloses an aeronautical turbomachine comprising a compressor blade equipped with an electric deicing device with a thermistor. The solution proposed by this document has room for improvement in terms of manufacturing process and heat conduction efficiency to achieve even more effective deicing.

[0009] The invention aims to propose a simple and economical manufacturing process making it possible to obtain a blade whose deicing is effective.

[0010] The invention is the result of technological research aimed at significantly improving aircraft performance and, in this sense, contributes to reducing the environmental impact of aircraft. For this purpose, the present invention relates to a turbomachine blade that is remarkable in that it comprises an electrical conductor completely covered with metallic material formed by dynamic projection by cold gas of a metallic powder.

[0011] This process has many advantages: it guarantees good thermal conductivity in the blade; ensures a surface condition compatible with the manufacturing constraints of a blade; and guarantees good durability in fatigue and / or against corrosion.

[0012] According to an advantageous embodiment of the invention, the metallic material consists of aluminum loaded with silicon carbide and / or alumina and / or contains other fillers, for example mineral fillers. These materials are both suitable for the spraying manufacturing process, are good thermal conductors and are light. Preferably, the metallic material consists mainly of aluminum from the 1xxx series (with at least 99% aluminum) or from the 2xxx series (having copper as the main alloying element) or from the 6xxx series (with magnesium and silicon as the main alloying elements).

[0013] According to an advantageous embodiment of the invention, with the exception of the electrical conductor and the metallic material, the blade is mainly made of an aluminum-based metal matrix composite material. Preferably, the metal matrix is ​​reinforced with 10% to 30% silicon carbide (SiC) particles. The aluminum constituting the metal matrix preferably corresponds to a 2xxx or 6xxx series.

[0014] According to an advantageous embodiment of the invention, the electrical conductor describes a pattern with a free end. The cold gas projection process in fact makes it possible to overcome certain design limits on the pattern described by the electrical conductor, unlike other manufacturing techniques which can be more restrictive.

[0015] According to an advantageous embodiment of the invention, the metallic material extends over at most half of the thickness of the blade. Thus, the quantity of metallic material remains in the minority over the entire blade.

[0016] The invention also relates to a method for manufacturing a turbomachine blade, the method comprising: manufacturing a body by forging, casting, machining and / or additive manufacturing; placing or depositing an electrical conductor on the body; and covering the electrical conductor by dynamic cold gas projection of a metal powder.

[0017] According to an advantageous embodiment of the invention, the manufacture of the body comprises the formation of a groove in the body, the placing or depositing step being such that the electrical conductor is placed or deposited in the groove.

[0018] According to an advantageous embodiment of the invention, the groove comprises a U-shaped or V-shaped profile or a Y-shaped funnel. Such a profile is simple to produce and helps to maintain the driver in position before and while he is covered with material.

[0019] According to an advantageous embodiment of the invention, the covering is such that the metallic material resulting from the dynamic projection by cold gas of a metallic powder fills the groove and is flush with the surface of the blade, or alternatively overflows from the groove.

[0020] According to an advantageous embodiment of the invention, the covering is carried out at low pressure, the gas preferably being brought to a pressure of between 3 and 10 bar. Also, the projection speed can be approximately 300 to 800 m / s. This prevents damage to the electrical conductor.

[0021] According to an advantageous embodiment of the invention, the electrical conductor comprises two electrical lines coated with an insulating sheath. These two lines can join at the end of the conductor, in order to close the electrical circuit.

[0022] According to an advantageous embodiment of the invention, the electrical conductor consists of a layer of copper powder sprayed by means of dynamic cold gas projection. This method allows total freedom over the pattern of the electrical conductor, and makes it possible to establish conductive “surface” zones that are more or less wide, or more or less dense, in accordance with local defrosting needs.

[0023] According to an advantageous embodiment of the invention, the method comprises a step of holding the electrical conductor in position on the body and possibly in the groove, said holding being ensured by at least one of the following means: gluing; soldering; over-cladding; placing of bridges; matting of the groove; use of a wheel combined with the cold gas projection tool and micro-welding.

[0024] According to an advantageous embodiment of the invention, the covering is such that the metallic material resulting from the dynamic projection by cold gas of a metallic powder constitutes in volume at most 50% of the total volume of the blade.

[0025] The invention also relates to a turbomachine compressor comprising a blade, remarkable in that the blade is according to one of the embodiments above or is manufactured at least in part by the method of one of the embodiments above.

[0026] It is understood that each detail of an embodiment above can be combined with each other detail of the other embodiments.

[0027] The metallic material covering the electrical conductor by dynamic projection by cold gas allows to ensure a better thermal conduction between the electrical conductor and the body of the blade thanks to the absence of porosity and a judicious choice of the materials present. The choice of the metallic material projected as well as the material constituting the body of the blade of the invention also allows to guarantee a followed mechanical and metallurgical compatibility, but also an advantageous durability of the electrical conductor, allowing it to resist fatigue and possible impacts of foreign bodies in operation. In addition, the risks linked to corrosion, galvanic for example, and erosion are avoided.

[0028] The thermal conductor of the invention makes it possible to effectively defrost the blade by allowing the latter to obtain a temperature of approximately 5°C on the surface, despite an outside temperature which can reach -40°C and an air flow speed of approximately 800 km / h.

[0029] The invention's blade makes it possible to minimize the amount of accreted ice likely to detach and damage other components of the turbomachine, thus making it possible to avoid obstruction of the vein in order to preserve the operability of the turbomachine.

[0030] As a result, the invention makes it possible to improve the performance of aircraft compressors and the overall efficiency of turbomachines, which translates into a reduction in fuel consumption and greenhouse gas emissions, thus reducing the environmental impact of aircraft.

[0031] The cold gas projection process allows material to be deposited without damaging the electrical conductor or the blade.

[0032] According to an advantageous embodiment, a re-machining of the surface state obtained can be carried out so as to ensure the aerodynamic function of the blade.

[0033] Cold spray also allows for good homogeneity and continuity of the material.

[0034] Cold spray allows good mechanical adhesion (no cavity, strong plastic deformation when the material is deposited) and physicochemical (metallurgical) adhesion with "compatible" materials placed in the presence of each other, for example aluminum or aluminum alloy.

[0035] Thus, there is a particular synergy between the blade material, the electrical conductor material (or sheath) and the cold spray material, which together ensure good mechanical strength and good thermal conductivity.

[0036] illustrates a sectional view of a compressor of a turbomachine comprising a blade according to the invention;

[0037] represents a method of manufacturing the blade according to the invention;

[0038] represents a front view of the blade comprising an electrical conductor according to one of the embodiments of the invention;

[0039] represents a partial perspective view of a cable corresponding to the electrical conductor of the blade of the;

[0040] is a sectional view of the blade along the axis AA according to the first embodiment of the invention;

[0041] schematizes the formation of a metallic material by dynamic projection by cold gas of a metallic powder;

[0042] illustrates an enlarged sectional view of the cable disposed in a groove of the blade of the;

[0043] is a sectional view of the blade along the axis AA according to the second embodiment of the invention;

[0044] is a sectional view of the blade along the axis AA according to a third embodiment of the invention. Detailed description

[0045] In the following description, the terms "internal" and "external" refer to a positioning relative to the axis of rotation of an axial turbomachine. The axial direction corresponds to the direction along the axis of rotation of the turbomachine, with lengths being measured axially. Widths are measured circumferentially. The radial direction is perpendicular to the axis of rotation. Upstream and downstream refer to the main flow direction of the flow in the turbomachine.

[0046] The dimensions of the figures are not to scale and in particular the thicknesses or radial dimensions are exaggerated to facilitate reading of the figures.

[0047] The figure represents a sectional view of a compressor 2 of an axial turbomachine 4.

[0048] The turbomachine 4 may correspond to a turbofan, turbojet, turbofan, turboprop, turboshaft, or any other type of two-flow turbomachine. Alternatively, the turbomachine 4 may correspond to a multi-flow turbomachine, such as a triple-flow unducted turbojet (CROR "Counter-Rotating Open Rotor" or USF "Unducted Single Fan"), or any other triple-flow turbomachine.

[0049] Preferably, the compressor 2 corresponds to a low-pressure compressor or a high-pressure compressor (not shown). The turbomachine 4 further comprises other components not shown in the, such as a high-pressure compressor, a combustion chamber and one or more turbine levels. The turbine(s) drive a rotor 6 in rotation. The rotor supports several rows of rotor blades 8 associated with rows of stator blades 10. The rotation of the rotor 6 around its axis of rotation X thus makes it possible to compress an air flow progressively up to the inlet of the combustion chamber.

[0050] A fan 12 (partially illustrated) is coupled to the rotor 6 and generates an air flow which is divided into a radially internal flow F1, commonly called primary flow F1, and into a radially external flow F', which may correspond to a secondary flow F' in the context of a double-flow turbomachine, or to a tertiary flow F' of a turbomachine 4 of the triple-flow type.

[0051] The primary flow F1 and external flow F' are separated by a separation nozzle 14.

[0052] The rotor blades 8 may extend radially from a rotor support 16 which may be of the drum type (one-piece bladed drum or any other type of rotor support).

[0053] The stator vanes 10 extend essentially radially from an outer casing 18. They can be fixed and immobilized there using fixing pins 20. They pass radially through the primary flow F1.

[0054] The low-pressure compressor 2 comprises at the inlet of the primary flow vein 22 F1, a row of rectifier stator vanes 9, 109, 209 which may be fixed or variable-pitch, commonly referred to as a VSV vane (for “Variable Stator Vane”). The variable pitch of the vanes 9, 109, 209 may be ensured by means of an actuation system (not shown) regulating the angle formed by the vanes 9, 109, 209 around an axis 24.

[0055] Each blade 9, 109, 209 comprises a blade 11 and two platforms 26 arranged at the two ends of the blade 11. Each platform 26 is provided with a journal 28 providing a pivot connection with the casings 18, 30, the platforms 26 being housed in housings 31 of these casings 18, 30. An outer surface 18.1 and a lower guide surface 30.1 delimit the vein 22.

[0056] In this upstream part of the turbomachine, certain elements are subject to frost. Thus, the blade 9, 109, 209 of the invention comprises a defrosting means.

[0057] The invention is not limited to VSV 9, 109, 209 blades, but can also be applied to other blades, VSV or not, stator or not.

[0058] The method represents a partial manufacturing process 100 of the blade 9, 109, 209 of the. The method is “partial” in the sense that other steps may occur, before or after, those described here.

[0059] The method 100 comprises a first step 102 corresponding to the manufacturing of the blade body by at least one of the following manufacturing techniques: forging, casting, molding, machining, fiber braiding and / or additive manufacturing. For example, the forged or molded blade can be machined in order to obtain the appropriate manufacturing tolerances. Or the blade can be entirely obtained by additive manufacturing with or without re-machining.

[0060] The blade of the present invention may be primarily made of a metal matrix composite material.

[0061] Preferably, the metal matrix composite material constituting the blade comprises an aluminum base reinforced with silicon carbide (SiC) particles (10 to 30% SiC by volume).

[0062] The aluminum constituting the metal matrix can be from the 2xxx series (with copper as the main alloying element) or from the 6xxx series (with magnesium and silicon as the main alloy).

[0063] The composite material constituting the blade of the invention may correspond to one or more elements among: 2009 / SiC / 15p-T4, 6092 / SiC / 17.5p-T6, 6092 / SiC / 25p-T6, 2124 / SiC / 25p-T4, etc.

[0064] Alternatively, the blade can be made from a composite material having a titanium base, and more precisely from a titanium alloy of the TA6V type.

[0065] The composite material can have a high cycle fatigue strength (HCF) that is much higher than that of aluminum, while having a density close to the latter. The blade stiffness can thus be close to that of titanium (classically used to manufacture turbomachine blades) while having better intrinsic properties, such as better thermal conductivity, which is beneficial for blade deicing.

[0066] Step 102 of manufacturing the body of the blade may comprise the production of an optional groove in the body of the blade and extending in particular along the blade 11, the groove opening onto the extrados or the intrados of the blade 11.

[0067] The method 100 then comprises a step 104 of placing or depositing an electrical conductor on the body of the blade manufactured in step 102.

[0068] For the blades 9 and 109 according to the first and second embodiments of the invention illustrated in the, the electrical conductor corresponds to an electrical cable and step 104 consists of placing the electrical conductor on the blade, or even in a groove established in the body of the blade. For the blade 209 according to the third embodiment illustrated in the, step 104 consists of depositing the electrical conductor by spraying a layer of copper.

[0069] Step 106 involves covering the conductor with sprayed metal, and the optional step 108 involves holding the cable before and partially during its covering with metal. These steps will be discussed later.

[0070] With reference to the, the blade 11 of the vane 9, 109 comprises a leading edge 11.1 and a trailing edge 11.2, as well as a lower surface 11.3 and an upper surface 11.4 extending from the leading edge 11.1 to the trailing edge 11.2.

[0071] The blade 9, 109 comprises an electrical cable 32 constituting the electrical de-icing conductor. The cable 32 preferably extends over the intrados 11.3 and following a sinuous path corresponding substantially to a spiral and / or serpentine pattern comprising a proximal portion 32.1 adjacent to the platform 26 at the blade head and a distal portion 32.2 close to the platform 26 at the blade root.

[0072] The cable 32 may extend over an entire surface of the blade 11 or, as illustrated, be confined to an upstream half of the blade 11. The cable may extend over approximately 80% (±10%) of a height H of the blade 11.

[0073] Preferably, the profile of the blade 9, 109 is slender with a ratio H / C (height on chord) greater than 5, and a thickness greater than 2 mm and less than 4 mm. For example, the height H can be equal to 200 mm and the chord C can vary from 20 mm to 40 mm.

[0074] The cable 32 preferably only passes through the upper platform 26 once to reach an electrical source (not shown). In this regard, an orifice passing through the intrados 11.3 and the platform 26 can be arranged at the right angle of the proximal part 32.1.

[0075] Optionally, and as illustrated in, a segment of the cable may extend along the pivot axis 24 of the blade 9, 109, or a median axis 11.5 of the blade 11. The cable 32 further comprises a non-linear portion 32.3, close to the proximal portion 32.1.

[0076] The pattern described by the cable 32 can thus comprise a first segment 33 along the axis 11.5, and extending to the distal part 32.2; then a second segment 33.1, parallel and close to the leading edge 11.1.

[0077] A third segment 33.2, connected to the second 33.1 by a rounded portion 32.4, can be interposed between the first two segments 33, 33.1. Other configurations are possible, and this “spiral” configuration can be supplemented by additional segments.

[0078] Preferably, the third segment 33.2 of the cable 32 extends in a central position between the first 33 and the second segment 33.1, so as to maintain laterally (along the axial direction of the turbomachine) an identical distance. This advantageously makes it possible to de-ice homogeneously the entire half of the blade 9, 109, each surface unit “seeing” the same density of cable and therefore of energy. The other part of the blade (which is much thinner) without cable will nevertheless be de-iced by thermal conduction.

[0079] The “spiral” pattern of the cable 32 preferably ends with a free end 32.5. The latter is advantageously arranged at approximately one third of the height H measured from the lower platform 26 at the foot of the blade 9, 109. Advantageously, this makes it possible to maintain a surface density covered by the cable 32 which is distributed homogeneously along the radial extent of the blade 9, 109, in order to uniformly de-ice the entire height H of the blade.

[0080] A free termination 32.5 is possible when the cable 32 comprises two electrical lines 34 capable of being connected together at the distal end 32.5.

[0081] To this end, illustrates these lines 34, being a partial perspective view of the cable 32 of the dawn of the.

[0082] It can be seen that the two electrical lines 34 correspond to two heating metal wires 34 which are covered with an insulating layer 36, the latter preferably being made of magnesia powder making it possible to electrically insulate the two wires 34 in order to allow only diffusion of thermal energy towards the blade of the vane of the invention.

[0083] The wires 34 and the insulating layer 36 are covered with a protective metal sheath 38, said sheath 38 being able to be made of stainless steel or aluminum alloy or Inconel® (superalloy containing mainly nickel). For this purpose, the cable 32 is advantageously a shielded resistive cable. The diameter of the sheath 38 can be of the order of 0.5 mm to 2 mm.

[0084] This is a sectional view along the axis AA of the blade 9 according to the first embodiment of the invention.

[0085] It can be seen that the blade 9 comprises a groove 40 receiving the cable 32. In this regard, and with reference to the method 100 of the, the step 104 of placing the electrical conductor in the body of the blade 9 comprises placing the cable 32 in the groove 40, and the step 102 of manufacturing the body comprises forming the groove 40 in the body.

[0086] Advantageously, the groove 40 makes it easier to mount the blade 9, to increase the thermal conductivity since the cable 32 is embedded in the blade 9 between the intrados 11.3 and the extrados 11.4, and to maintain a smooth extrados or intrados surface without asperities (post re-machining).

[0087] Preferably, the depth of the groove 40 is constant over the entire blade.

[0088] The groove 40 is covered by a filling material 42 advantageously corresponding to a metal powder which is flush with the intrados 11.3.

[0089] Indeed, the method 100 for manufacturing the blade 9 comprises a step 108 of covering the electrical conductor 32 with a metallic material. The metallic coating is obtained by dynamic projection by cold gas of a metallic powder.

[0090] Cold gas dynamic projection, also known as "cold spray", is a process for producing a coating from powder suspended in a gas projected at high speed and deforming on impact.

[0091] Laschematizes the principle of the formation of metallic material by the cold spray process.

[0092] The left part of the illustrates the projection of a particle 44 of metal powder in the solid state comprising a size ranging from 10 µm to 100 µm, and projected at a speed of between 300 and 1400 m / s. A supersonic impact S on a substrate 46 is expected. In the context of the invention, the substrate 46 is the body of the blade 9, 109, 209 as well as the electrical conductor.

[0093] It can be seen at the central part of the lacquer that the supersonic impact has caused a plastic deformation 47 of the particle 44 and the substrate 46, this deformation is followed by a generation of heat transferred through the substrate 46. In this configuration, a successive projection of particles 44 generates a successive deformation of said particles 44 followed by an isotropic heat transfer, thus forming a layer 48 comprising particles 44 linked by plastic deformation.

[0094] The successive powder elements agglomerate without cavities between them. They become mechanically and metallurgically united via their plastic deformation.

[0095] It is thus possible to detect this manufacturing process on the finished part, by observing the deformed grains and the absence of cavities between successive layers resulting from plastic deformation on impact.

[0096] Illustrates an enlarged sectional view of the, showing in particular the cable 32 in its groove 40.

[0097] The electrical conductor 32 is covered with the metallic material 42 projected by the cold spray process. Preferably, the metallic powder of the material 42 covering the cable 32 is mainly made of aluminum, the latter preferably being from the 1xxx series (with at least 99% aluminum) or from the 2xxx or 6xxx series, and this with or without loading with silicon carbide (SiC) balls and / or alumina (Al2O3) balls and / or other fillers.

[0098] The loading of SiC and / or Al2O3 and / or other fillers can be chosen depending on the pressure used during the cold spray. In fact, the cold spray is carried out using an inert gas (nitrogen and / or helium) or pressurized air between 4 and 60 bars heated between 500°C and 1000°C. We speak of high pressure when the gas is between 10 and 60 bars, the loading of balls then becomes optional and the aluminum is preferably from the 6xxx series.

[0099] For the present invention, low pressure cold spray is preferred, in particular between 3 and 10 bars, the powder being propelled at a speed of approximately 300 to 800 m / s. This advantageously makes it possible to avoid damage to the sheath 38 of the cable 32 and to have a narrow bead of material deposited.

[0100] The cold spray ensures good adhesion of the material 42 to the blade, said sprayed material 42 being compact and dense (with a porosity rate generally less than 1%), allows the electrical conductor to be effectively maintained and protected.

[0101] The material 42 may be capable of undergoing a surface treatment of the blade, for example, anodization.

[0102] The material 42 may be flush with the surface of the blade. Alternatively, the material 42 may extend beyond the groove 40 to cover part or all of the surface 11.3 of the blade 9.

[0103] The intended filling of the groove 40 is complete, i.e. the blade is free of any cavity. The cable 32 and the filling material 42 may be the only two elements in the groove.

[0104] Illustrates a groove 40 having a hemispherical bottom, of diameter slightly greater than the external diameter of the cable 32. The bottom can alternatively be straight.

[0105] The cable 32 can optionally be oversheathed to protect it even more during the cold spray stage or to facilitate the maintenance of the cable by deformation of the sheath or to limit the number of materials in contact.

[0106] The sides of the groove 40 may be straight, so that the profile of the groove 40 is a U. Alternatively (see dotted lines on the), the profile of the groove (denoted 41) may be V-shaped or Y-shaped (funnel type).

[0107] A V-shape allows for greater flexibility in choosing the direction of projection during cold spray.

[0108] Preferably, the side walls of the V-shaped groove 41 have an inclination relative to the direction perpendicular to the intrados 11.3 which is between 10° and 60°.

[0109] The cable 32 is held as close as possible to the bottom. In this regard, and with reference to the method 100 of the, the method comprises, after the step 104 of placing the cable in the groove, and in parallel with the cold spray projection, a step 108 of holding the cable 32 in position. The holding in position 108 begins before the cold spray 106 and may end before completing the cold spray step 106. The holding step 108 may comprise holding the cable 32 in the groove 40. Different techniques may be used, such as for example: gluing; soldering; oversheathing; placing bridges; caulking the groove; use of a wheel combined with the cold gas projection tool, microwelding.

[0110] For example, a few dots of glue or solder can be made to hold the cable in the groove, and then the cold spray step is performed.

[0111] In a variant, a few bridges can be arranged at regular intervals on the cable tray 32, then, little by little during the cold spray, the bridges which have become superfluous are removed.

[0112] In one variation, an oversheathing wedges the cable sheath into the bottom of the groove.

[0113] In another variant the sides of the groove are mated (plastically deformed), locally, to reduce the opening of the groove and prevent the cable from coming out.

[0114] Another possible technique is to mat a wire above the cable 32. The wire can be aluminum or nickel (or any other malleable material). The mated wire holds the cable 32 at the bottom of the groove. This is followed by the cold spray, the wire being embedded in the material with the cable 32.

[0115] Other alternatives for holding the cable 32 include performing laser microwelding or soft soldering points; or performing soldering points via a ball capacitor (microwelded bond).

[0116] Finally, any combination of at least two of these techniques can be considered.

[0117] Theis a sectional view of the blade of thealong the axis AA. In this second embodiment of the invention, the numbers are incremented by 100 to designate distinctive elements or having differences compared to the first embodiment of the.

[0118] The blade 109 includes a groove 140 receiving the cable 32. Unlike the example of 1a, the groove 140 does not follow the path traveled by the cable 32 since the groove 40 is wide enough to receive the entire serpentine (or other shaped) pattern.

[0119] Advantageously, the groove 140 can be quickly filled with the metallic material 42, for example, by means of a projection nozzle of the tool producing the cold spray which is larger than that producing the projection onto the blade 9.

[0120] In this configuration, the volume of powder projected to constitute the material 42 can reach up to 50% of the total volume of the blade 109.

[0121] In this regard, the blade 109 can be obtained by means of the succession of steps 102, 104, 106 and 108 of the method 100 illustrated in, similarly to the blade 9 according to the first embodiment.

[0122] It can be seen that the bottom 140.1 of the groove 140 is flat, and the cable 32 is directly deposited on the flat bottom 140.1. A larger groove compared to the here allows a greater manufacturing tolerance on the groove and greater ease in inserting the cable into the groove.

[0123] This is a sectional view of the blade 209 along the axis AA according to a third embodiment of the invention.

[0124] The blade 209 may comprise the groove 140 similarly to the blade 109. In this configuration, the electrical conductor 232 of the blade 209 corresponds to a layer of copper powder sprayed by means of dynamic cold gas spraying. Advantageously, the conductor 232 comprises excellent thermal conductivity due to the copper that constitutes it.

[0125] For this purpose, step 104 consists, for the blade 209, in depositing the electrical conductor 232. Step 106 of the method 100 illustrated in la consists in this case of covering the copper layer with a metal powder projected by cold gas. In this configuration, the projected electrical conductor 232 does not need to be held in position (step 108) before being covered by the metallic material 42.

[0126] The electrical conductor 232 can reach the electrical source (not shown) by means of an orifice passing through the intrados and the platform in a manner similar to the first and second embodiments of the invention.

[0127] Electrical insulation (not shown) may be disposed between the electrical conductor 232 and the material 42 in order to electrically insulate the latter. This insulation may correspond to a layer of magnesia powder.

[0128] If illustrates a broad profile for the copper layer – and thus a band rather than a linear path, the copper layer can alternatively be narrower and describe a path like that of the.

[0129] As an alternative to cold spray metal material, the electrical conductor can be covered by brazing. Brazing ensures good heat transfer between the de-icing conductor and the blade. Optional re-machining (e.g., polishing) may be required.

[0130] Another alternative to cold sprayed metallic material can be resin injection to ensure the covering of the electrical conductor.

[0131] It should be noted that the invention was presented for deicing a blade but the person skilled in the art would adapt the same teachings to deicing any other part of the turbomachine (shell, casing, structural arms, flow separation nozzle, etc.), by depositing an electrical conductor then covering it by projection with cold gas.

Claims

Blade (9; 109; 209) of a turbomachine (4) characterized in that it comprises an electrical conductor (32; 232) completely covered with metallic material (42) formed by dynamic projection by cold gas of a metallic powder. Blade (9; 109; 209) according to claim 1, characterized in that the metallic material (42) consists of aluminum loaded with silicon carbide and / or alumina and / or contains other fillers. Blade (9; 109; 209) according to one of claims 1 or 2, characterized in that with the exception of the electrical conductor (32; 232) and the metallic material (42), the blade (9; 109; 209) is mainly made of an aluminum-based metal matrix composite material. Blade (9; 109; 209) according to one of claims 1 to 3, characterized in that the electrical conductor (32; 232) describes a pattern with a free end (32.5). Blade (9; 109; 209) according to one of claims 1 to 4, characterized in that the metallic material (42) extends at most over half the thickness of the blade. Method (100) for manufacturing a blade (9; 109; 209) of a turbomachine (4), the method (100) comprising:- manufacturing (102) a body by forging, casting, machining and / or additive manufacturing;- placing (104) or depositing an electrical conductor (32; 232) on the body; and- covering (108) the electrical conductor (32; 232) by dynamic projection by cold gas of a metal powder. Method (100) according to claim 6, characterized in that the manufacturing of the body comprises the formation of a groove (40; 41; 140) in the body, the step of placing (104) or depositing being such that the electrical conductor (32) is placed or deposited in the groove (40; 41; 140). Method (100) according to claim 7, characterized in that the groove (40; 41; 140) comprises a U-shaped or V-shaped profile or a Y-shaped funnel. Method (100) according to one of claims 7 or 8, characterized in that the covering (108) is such that the metallic material (42) resulting from the dynamic projection by cold gas of a metallic powder fills the groove (40; 41; 140) and is flush with the surface (11.3) of the blade (9; 109; 209), or alternatively overflows from the groove (40; 41; 140). Method (100) according to one of claims 6 to 9, characterized in that the covering (108) is carried out at low pressure, the gas preferably being brought to a pressure of between 3 and 10 bar. Method (100) according to one of claims 6 to 10, characterized in that the electrical conductor (32) comprises two electrical lines (34) coated with an insulating sheath (38). Method (100) according to one of claims 6 to 10, characterized in that the electrical conductor (232) consists of a layer of copper powder sprayed by means of dynamic projection by cold gas. Method (100) according to one of claims 6 to 11, characterized in that it comprises a step (106) of holding the electrical conductor (32) in position on the body and possibly in the groove (40; 41; 140), said holding (106) being ensured by at least one of the following means: gluing; soldering; over-cladding; placing bridges; matting the groove (40; 41; 141); use of a wheel combined with the cold gas projection tool; micro-welding. Method (100) according to one of claims 6 to 13, characterized in that the covering is such that the metallic material (42) resulting from the dynamic projection by cold gas of a metallic powder constitutes in volume at most 50% of the total volume of the blade (9; 109; 209). Compressor (2) of a turbomachine (4) comprising a blade (9; 109; 209), the compressor being characterized in that the blade (9; 109; 209) is according to one of claims 1 to 5 or is manufactured at least partially by the method according to one of claims 6 to 14.

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