Industrial process for heat treatment of carbon precursor material preforms for manufacturing C / C parts

Abstract

The invention relates to an industrial process for the heat treatment of a preform made of a carbon precursor material, the process comprising the following sequential steps:-introducing (S10) a charge of preforms made of a carbon precursor material into a first sealing air brake, the first sealing air brake selectively communicating with a first furnace; replacing (S20) the air present in the first damper with a neutral gas; transferring (S30) the load into the first furnace; -performing a first carbonization treatment (S40) in the first furnace; transferring (S50) the load into a second sealing air brake, which is selectively in communication with the first furnace and the second furnace; -evacuating (S60) the second sealing damper; -transferring (S70) the load into the second furnace; -performing a second carbonization treatment in a second furnace (S80); -transferring (S80) the load into a third sealing air brake, which is selectively in communication with the second furnace and the open air outlet.

Description

Technical Field

[0001] This invention relates to the general field of manufacturing parts made of carbon-carbon composite materials (C / C). Background Technology

[0002] US 6183583 discloses a process for obtaining parts made of C / C composite materials, including the following steps: - Fabrication of fiber preforms using fibers made from carbon precursors such as polyacrylonitrile or PAN; - Heat treatment, known as carbonization, involves purifying the PAN fibers and the carbon that makes up the preform; - Densification of preforms is achieved through chemical vapor infiltration.

[0003] The heat treatment of fiber preforms involves two steps: primary carbonization and secondary carbonization. The primary carbonization step is carried out at high temperatures in dedicated batch furnaces. A large amount of flue gas must be emitted during primary carbonization. The secondary carbonization step of the fiber preforms is carried out at extremely high temperatures and low pressures, also in a dedicated batch furnace, but different from the furnace used for primary carbonization. A large amount of flue gas must also be emitted during secondary carbonization.

[0004] The initial carbonization process lasts approximately two to three days, while the secondary carbonization process lasts approximately four to five days.

[0005] Although the furnaces used for primary and secondary carbonization are large enough to process hundreds of preforms simultaneously, the loading and unloading of these processes requires handling large numbers of preforms, making operation quite challenging. These operations are difficult to automate and can lead to poor quality. Each carbonization process also requires heating the furnace to reach the preform processing temperature, followed by cooling the furnace and equipment to allow the preforms to be unloaded after processing. These steps are energy-intensive, and their duration reduces furnace capacity. Furthermore, the size of batch furnaces is limited by loading and unloading constraints and the requirement for uniform furnace shell temperature. The same applies to the high-temperature processing of the densified component blanks.

[0006] Therefore, when increased production capacity is needed, more dedicated furnaces must be used simultaneously. This solution is not optimal because it leads to high levels of investment and a significant increase in overall energy costs.

[0007] Therefore, it is necessary to increase the production capacity of high-temperature treatment of preforms after carbonization and densification, while controlling investment costs and energy consumption. Summary of the Invention

[0008] Therefore, the present invention proposes an industrial process for heat-treating preforms made of carbon precursor materials, the process comprising the following steps in a sequential manner: - A loading device consisting of one or more preforms made of carbon precursor material is introduced into a first sealing gaslock, which is selectively connected to a first furnace; - Replace the air present in the first sealed airlock with a neutral gas; - Transfer the load into the first furnace; - Each preform of the loading component undergoes a first carbonization process in the first furnace; - The loading component is transferred to a second sealing airlock, which is selectively connected to the first and second furnaces; - Evacuate the second airlock; - Transfer the loading component to the second furnace; - Each preform of the loading component undergoes a second carbonization process in a second furnace; - The loading component is transferred to a third sealed airlock, which is selectively connected to the second furnace and the open outlet.

[0009] By combining two furnaces with a gas damper, a continuous carbonization process line can be created. This increases the capacity of carbonized preforms without increasing the number or size of the furnaces, thus keeping investment costs manageable.

[0010] Furthermore, the process of this invention does not require interruption of heating of the furnace used for carbonization. This enables increased productivity and optimized energy consumption, as almost all the energy used to heat the furnace is devoted to carbonization, whereas prior art intermittent furnaces use a significant amount of energy outside of carbonization to reheat the furnace after each unloading of preforms.

[0011] According to specific features of the industrial process of the present invention, a loading of one or more preforms of carbon precursor materials is introduced into the first airlock at defined time intervals. Therefore, productivity can be defined.

[0012] According to another specific feature of the industrial process of the invention, the flue gas released during the first and second treatments of each preform is combusted in the same thermal oxidizer. Since the furnace used in the process of the invention operates continuously, the thermal oxidizer is permanently supplied by the combustion of flue gas. Therefore, the thermal oxidizer is always maintained at its operating temperature without the need for natural gas, which is typically added during stages when there is no flue gas emission, particularly corresponding to cooling and unloading stages, cycle intervals, and loading into prior art batch furnaces, to maintain the oxidizer at its operating temperature; these stages correspond to more than 70% of the production time. Furthermore, even if the flue gas flow rate from the second carbonization treatment is too low to maintain the oxidizer at the correct temperature, the oxidizer temperature is still maintained by the flue gas released from the first carbonization treatment, which has a much higher flow rate.

[0013] According to another specific feature of the industrial process of the invention, the first and second furnaces are flushed with a neutral gas. This helps to remove the flue gas released during the first and second carbonization processes. At least the mass flow rate of the neutral gas in the first furnace can be determined based on the mass flow rate of the flue gas in order to limit the effect of the neutral gas (dilution) on the supply of flue gas to the oxidizer.

[0014] According to another specific feature of the industrial process of the invention, a second furnace is alternately connected to a first cold trap and a second cold trap, each cold trap being configured to condense the flue gas released by each preform during the second carbonization process. The process includes the step of cleaning the first cold trap when the second cold trap is connected to the second furnace (the second cold trap is operational), and vice versa.

[0015] According to another specific feature of the industrial process of the present invention, during the first carbonization process and the second carbonization process, the loading component sequentially passes through multiple heating zones respectively present in the first and second furnaces, with the heating temperature gradually increasing to a maximum heating temperature between the first heating zone and the last heating zone. As the preform loading component moves within each furnace, the temperature rise conditions (thermal gradient) encountered in the prior art static furnace are recreated.

[0016] According to another specific feature of the industrial process of the present invention, during the first carbonization process, the highest heating temperature in the last heating zone of the plurality of heating zones is between 700°C and 1000°C, wherein the temperature rise rate between the first heating zone and the last heating zone of the plurality of heating zones is less than 400°C / h.

[0017] According to another specific feature of the industrial process of the present invention, during the second carbonization process, the highest heating temperature in the last heating zone of the plurality of heating zones is between 1500°C and 2600°C, wherein the temperature rise rate between the first heating zone and the last heating zone of the plurality of heating zones is less than 1500°C / h.

[0018] According to another specific feature of the industrial process of the invention, the process includes a step of cooling each preform of the load after the second carbonization step and before the step of transferring the load to the third sealing airlock.

[0019] This invention also relates to a manufacturing process for a carbon-carbon composite material component, comprising the following steps: - An industrial process according to the invention for heat-treating preforms made of carbon precursor materials; - Densification of preforms using a carbon matrix to obtain component blanks; - High-temperature treatment of component blanks. Attached Figure Description

[0020] Other features and advantages of the invention will become apparent from the description given below with reference to the accompanying drawings, which illustrate examples of embodiments of the invention and are by no means limiting.

[0021] [ Figure 1 ] Figure 1 An apparatus for carrying out an industrial heat treatment process according to an embodiment of the present invention is illustrated schematically; [ Figure 2 ] Figure 2 A schematic cross-sectional view is shown. Figure 1 The first section of the device; [ Figure 3 ] Figure 3 A schematic cross-sectional view is shown. Figure 1 The second section of the device; [ Figure 4 ] Figure 4 An example of a carbon precursor material preform loaded with an industrial process that can be used in the present invention is shown schematically in cross-sectional view; [ Figure 5 ] Figure 5 This is a flowchart illustrating the industrial process steps of manufacturing a component made of carbon-carbon composite material according to an embodiment of the present invention, the industrial process including heat treatment of a preform made of carbon precursor material. Detailed Implementation

[0022] Figure 1 The heat treatment apparatus 1 is shown schematically, in which an industrial process according to the invention for heat treatment of preforms made of carbon precursor materials can be carried out.

[0023] Device 1 along the direction of travel D P From upstream to downstream, it includes an open-air loading device 10, a first sealed airlock 20, a first furnace 100, a second sealed airlock 30, a second furnace 200, a third sealed airlock 40, and an open-air discharge device 50.

[0024] The first furnace 100 is specifically intended to perform a first carbonization process, also known as primary carbonization. The second furnace 200 is specifically intended to perform a second carbonization process, also known as secondary carbonization.

[0025] The first airlock 20 is respectively connected to the first movable door 21 and the second movable door 22 according to three configurations. Figure 2The airlock 20 is selectively connected to the loading device 10 and the first furnace 100. In a first configuration, the first airlock 20 is connected to the open-air loading device 10 by opening the first movable door 21 to allow the precast component to be introduced into the airlock, while the first airlock 20 is isolated from the first furnace 100 by closing the second movable door 22. In a second configuration, the airlock 20 is isolated from both the loading device 10 and the first furnace 100 by closing both movable doors 21 and 22, and then the airlock forms a sealed enclosure around the precast component. In a third configuration, the airlock 20 is connected to the first furnace 100 by opening the second movable door 22, while the airlock 20 is isolated from the loading device 10 by closing the first movable door 21, to allow the precast component to be transferred into the first furnace 100.

[0026] The second airlock 30 is respectively connected to the first movable door 31 and the second movable door 32 according to three configurations. Figure 2 and Figure 3 The second airlock 30 is selectively connected to the first furnace 100 and the second furnace 200. In a first configuration, the second airlock 30 is connected to the first furnace 100 by opening the first movable door 31, thereby allowing the introduction of the preform loading material after the first carbonization treatment into the airlock, while the second airlock 30 is isolated from the second furnace 200 by closing the second movable door 32. In a second configuration, the airlock 30 is isolated from both the first furnace 100 and the second furnace 200 by closing both movable doors 31 and 32, and then the airlock forms a sealed enclosure around the preform loading material. In a third configuration, the airlock 30 is connected to the second furnace 200 by opening the second movable door 32, while the airlock 30 is isolated from the first furnace 100 by closing the first movable door 31, to allow the preform loading material to be transferred into the second furnace 200.

[0027] The third airlock 40, according to three configurations, passes through the first movable door 41 and the second movable door 42 respectively. Figure 3 The third airlock 40 is selectively connected to the second furnace 200 and the unloading device 50. In the first configuration, the third airlock 40 is connected to the second furnace 200 by opening the first movable door 41, thereby allowing the introduction of the precast component load after the second carbonization treatment into the airlock, while the third airlock 40 is isolated from the unloading device 50 by closing the second movable door 42. In the second configuration, the airlock 40 is isolated from both the second furnace 200 and the unloading device 50 by closing both movable doors 41 and 42. In the third configuration, the airlock 40 is connected to the open-air unloading device 50 by opening the second movable door 42, while the airlock 40 is isolated from the second furnace 200 by closing the first movable door 41, so as to allow the precast component load to leave the device 1.

[0028] Figure 2 The first section of the apparatus 1 is shown, including an open-air loading device 10, a first sealed airlock 20, a first furnace 100, and a second sealed airlock 30.

[0029] The first furnace 100 is defined by a cylindrical shell 101 located between a first sealing airlock 20 and a second sealing airlock 30. The furnace 100 includes a processing chamber 140, and a loading member 300 for carbon precursor material preforms is located inside the processing chamber 140 along the direction of travel D. P The process chamber 140 is surrounded by heating equipment 110 and an insulating element 102 disposed between the enclosure 101 and the heating equipment 110. The first furnace 100 has the shape of a tunnel, which extends between an inlet 103 that selectively communicates with a first airlock 20 and an outlet 104 that selectively communicates with a second airlock 30.

[0030] The first furnace 100 also includes a motion device 150, such as a conveyor belt, pusher, or any other suitable system, which enables motion at a defined speed along the direction of travel D. P The loading unit 300 is moved in the processing chamber 140.

[0031] In the example described herein, the processing chamber 140 includes multiple heating zones Z1 to Z6, each independently temperature-controlled by a heating device 110. In the example described herein, the heating device 110 includes resistance heating elements (…). Figure 2 (Not shown in the diagram), which are distributed around each heating zone Z1 to Z6 and controlled to regulate the temperature of each heating zone. Of course, other heating means capable of controlling the temperature of each heating zone can be used. Heating of the heating zone can be performed, for example, by induction. In this case, the reaction chamber is surrounded by an armature or base, which is made of graphite, for example, and coupled to inductors located outside the reaction chamber, each inductor being formed by at least one induction coil.

[0032] As the preform moves within the processing chamber 140, the heating zone allows for a gradual increase in the preform's processing temperature. For the loading component 300 in the direction of travel D... P Given a given moving speed, the length of the heating zone determines the dwell time (plateau period) of the loading component in each heating zone.

[0033] The first furnace 100 also includes an extraction system 130 for discharging flue gas released during the carbonization process of the preforms. More specifically, the extraction system 130 includes a suction pipe 131 present in a treatment chamber 140, which extends from an exhaust pipe 132 connected to a thermal oxidizer 133, also known as a thermal incinerator. The treatment chamber 140 also provides a neutral gas source ( Figure 2 (not shown in the image), enabling the processing chamber to be flushed with neutral gas so that the extraction system 130 can discharge the flue gas.

[0034] Figure 3The second section of device 1 is shown, including a second sealed airlock 30, a second furnace 200, a third sealed airlock 40, and an open-air discharge device 50.

[0035] The second furnace 200 is defined by a cylindrical shell 201 located between a second sealing gas valve 30 and a third sealing gas valve 40. The furnace 200 includes a processing chamber 240, and a loading member 300 for carbon precursor material preforms is located inside the processing chamber 240 along the direction of travel D. P The process chamber 240 is surrounded by heating equipment 210 and an insulator 202 disposed between the casing 201 and the heating equipment 210. The second furnace 200 has a tunnel shape, extending between an inlet 203 selectively communicating with a second airlock 30 and an outlet 204 selectively communicating with a third airlock 40. In the example described herein, the second furnace 200 also includes a cooling unit 260 located inside the casing 201 and positioned between the process chamber 240 and the third outlet airlock. The cooling unit 260 may be equipped with a heat exchange system (…). Figure 3 (not shown in the image), thereby accelerating the cooling of the loading component 300 in the cooling unit.

[0036] The second furnace 200 also includes a motion device 250, such as a conveyor belt, pusher, or any other suitable system, which enables motion at a defined speed along the direction of travel D. P The loading unit 300 is moved in the processing chamber 240 and the cooling unit 260.

[0037] In the example described herein, the processing chamber 240 includes multiple heating zones Z7 to Z8, each with an independent temperature control by the heating device 210. 14 In the example described herein, heating device 210 includes a resistance heating element (… Figure 3 (not shown in the image), which surrounds each heating zone Z7 to Z... 14 The heating elements are distributed and controlled to regulate the temperature of each heating zone. Of course, other heating methods capable of controlling the temperature of each heating zone can be used. Heating of the heating zones can be, for example, by induction. In this case, the reaction chamber is surrounded by an armature or base, which is made of graphite, for example, and coupled to inductors outside the reaction chamber, each inductor being formed by at least one induction coil.

[0038] As the preform moves within the processing chamber 240, the heating zone allows for a gradual increase in the preform's processing temperature. For the loading component 300 in the direction of travel D... P Given a given moving speed, the length of the heating zone determines the dwell time (plateau period) of the loading component in each heating zone.

[0039] The second furnace 200 also includes an extraction system 230 for discharging flue gas released during the carbonization process of the preforms. More specifically, the extraction system 230 includes a suction pipe 231 present in the processing chamber 240, extending from an exhaust pipe 232, which is itself connected to a first cold trap 234 and a second cold trap 235, each configured to condense the flue gas released from each preform during the second carbonization process. In the example described herein, the exhaust pipe 232 is selectively connected to the first cold trap 234 and the second cold trap 235 via a three-way valve 233. Any other selective connection is conceivable. The outlets of the cold traps 234 and 235 are connected to a vacuum pump 236, enabling it to pump the processing chamber 240 for the second carbonization process at a reduced pressure (typically between 1 mbar and 100 mbar). The outlet 237 of the vacuum pump 236 is connected to a thermal oxidizer 133.

[0040] The cold trap works on the same principle as a shell-and-tube heat exchanger. The tubes through which the flue gas passes are cooled by water circulating inside the shell. Once the tubes are filled, they are cleaned by injecting water into them and then drying them under vacuum.

[0041] When the first cold trap is operating to capture solid deposits (silicon, alkali, etc.) contained in the flue gas, the second cold trap, which is not connected to the second furnace, is cleaned. Conversely, when the second cold trap is operating, the first cold trap, which is not connected to the second furnace, is cleaned. Therefore, the cold traps can be cleaned without interrupting the heat treatment process.

[0042] Processing chamber 240 is also equipped with a neutral gas source ( Figure 3 (not shown in the image), enabling the treatment chamber to be flushed with neutral gas so that the extraction system 230 can discharge the flue gas.

[0043] Figure 4 An example of a loading device 300 for preforms made of carbon precursor material is shown. The loading device 300 includes a loading tool 310 comprising a support plate 311 configured to mate with motion devices 150 and 250, a support cylinder 312 extending from the support plate 311, and an intermediate plate 313 extending from the support cylinder 312. Multiple annular preforms 350 of carbon precursor material are stacked on the support plate 311 and the intermediate plate 313, respectively. A loading tray 314 is placed on top of each stack of preforms 350 to control deformation and warping of the preforms during their processing.

[0044] Preform 350 is made of carbon precursor fibers, which may be, for example, pre-oxidized polyacrylonitrile (PAN), pitch, rayon, or phenolic compounds. Each preform 350 may, for example, be made at least partially of continuous elements forming a multidirectional two-dimensional texture. It may be a woven fabric, braided fabric, knitted fabric, unidirectional layer, or a stack of several layers of unidirectional yarns, cables, or strands. These layers are stacked in different directions and assembled by light needle punching. For example, the basic texture may consist of three unidirectional layers arranged at angles of 0°, +60°, and -60° relative to the texture axis, respectively. Alternatively, the basic texture may be supplemented by a thin fiber web pre-needled onto the texture. An exemplary embodiment of such annular preforms is specifically described in US 6,767,602. The preforms described herein are intended for use in manufacturing brake discs made of carbon-carbon materials.

[0045] Now for reference Figure 5 An industrial process for manufacturing parts made of carbon-carbon materials according to embodiments of the present invention is described, the industrial process including heat treatment of preforms made of carbon precursor materials and high-temperature treatment of part blanks.

[0046] The industrial method of the present invention is particularly applicable to the processing of preforms 350 packaged in a loading container 300 as described above. However, the industrial method of the present invention is generally applicable to any type of preform and any type of loading container made of carbon precursor material. For example, each loading container may hold one or more preforms, which may optionally have different shapes and sizes from the annular preforms 350 and / or have shapes and sizes different from each other.

[0047] An industrial process for heat-treating a preform made of carbon precursor material is described herein, which is carried out in the heat treatment apparatus 1 as described above and follows the path of the loading 300 of the preform made of carbon precursor material 350 as described above.

[0048] The industrial heat treatment process begins by introducing a loading 300 of a preform made of carbon precursor material 350 from an open loading device 10 into a first sealed airlock 20 (step S10), wherein a first movable door 21 is open and a second movable door 22 is closed.

[0049] Then, the sealing gas valve 20 is closed (the first movable door 21 and the second movable door 22 are closed), and the air present inside it is pumped out and replaced with a neutral gas, such as nitrogen or argon (step S20). At this stage, the loading unit 300 is in an atmosphere compatible with that of the first furnace 100, since it no longer contains oxygen.

[0050] Once the air present in the first airlock 20 is replaced by a neutral gas, the second movable door 22 of the airlock 20 can be opened. Then, the loading unit 300 is transferred to the first furnace 100 (step S30).

[0051] Loader 300 along the direction of travel D P The preform made of carbon precursor material 350 is passed through processing chamber 140 of furnace 100 for a first carbonization treatment (step S40). The loading component 300 sequentially passes through heating zones Z1 to Z6, with the heating temperature gradually increasing from the initial temperature of the first heating zone Z1 (e.g., 300°C) to the highest heating temperature of the last heating zone Z6. The highest heating temperature of the last heating zone Z6 is between 700°C and 1000°C, and the temperature rise rate between the first heating zone Z1 and the last heating zone Z6 is less than 400°C / h. The first carbonization treatment is carried out at a pressure close to atmospheric pressure.

[0052] During the first carbonization process, the temperature rise of the preform 350 leads to a dramatic release of gaseous substances including HCN, NH3, CO, CO2, and H2. In the case where the preform contains pre-oxidized PAN fibers, these fibers lose approximately 51% of their mass during carbonization. The mass flow rate of the released flue gas is related to a time interval (also known as a cycle time) corresponding to the time interval between the loading unit passing through position n and position n+1 in the heat treatment apparatus. This cycle time may, for example, correspond to the time interval between the loading unit passing through the first gas gate (position n) and the first furnace inlet (position n+1), or the time interval between the loading unit passing through the outlet of the cooling unit (position n) and the third gas gate (position n+1). The flue gas mass flow rate Dme can be determined by the formula Dme = ρ.m / τ, where ρ is the mass loss, m is the mass of pre-oxidized PAN in the stack, and τ is the transfer time interval.

[0053] The flue gas generated during preform carbonization is destroyed by a thermal oxidizer (here, thermal oxidizer 133). Through continuous processing in furnace 100, thermal oxidizer 133 can be maintained at its operating temperature solely by the heat calorific value of the flue gas without the addition of natural gas. This constitutes an advantage over carbonization processes performed in batch furnaces with very high natural gas consumption, allowing the thermal oxidizer to be maintained at its operating temperature during periods without flue gas emissions, as is the case during the loading, heating, cooling, and unloading phases of the preforms.

[0054] Preferably, the flue gas is entrained by flushing the treatment chamber of the furnace with a neutral gas, such as nitrogen. Too low a neutral gas flow rate can lead to tar formation on the fibers, while too high a flow rate can be detrimental to combustion in the thermal oxidizer (due to the dilution of the flue gas's caloric input). The neutral gas mass flow rate Dmg can be defined as a function of the flue gas mass flow rate Dme according to the rule Dmg = k * Dme, where k is between 0.3 and 3.

[0055] At the outlet of the processing chamber 140 of the first furnace 100, i.e. after the first carbonization process, the loading 300 is transferred to the second sealing gas valve 30 (step S50), wherein the first movable door 31 is opened and the second movable door 32 is closed.

[0056] Then the sealing airlock 30 is closed (the first movable door 31 and the second movable door 32 are closed). Then, the sealing airlock 30 is evacuated (step S60). In this stage, the loading component 300 is in an atmosphere compatible with the atmosphere of the second furnace 200, and the second carbonization process is carried out under vacuum in the second furnace.

[0057] Once a vacuum has been created in the second airlock 30, the second movable door 32 of the airlock 30 can be opened. Then, the loading unit 300 is transferred to the second furnace 200 (step S70).

[0058] Loader 300 along the direction of travel D P The preform made of carbon precursor material 350 passes through the processing chamber 240 of furnace 200 for a second carbonization treatment (step S80). The loading component 300 sequentially passes through heating zones Z7 to Z8. 14 The heating temperature gradually increases from the initial temperature of the first heating zone Z7 (e.g., 800℃) to the temperature of the last heating zone Z. 14 The highest heating temperature. The last heating zone Z. 16 The maximum heating temperatures range from 1500℃ to 2600℃, with the first heating zone Z7 and the last heating zone Z... 14 The temperature rise rate between them is less than 1500℃ / h.

[0059] The amount of flue gas released during the second carbonization process is significantly less than the amount of flue gas emitted during the second carbonization process.

[0060] The flue gas generated from the second carbonization process of the preform is destroyed by the same thermal oxidizer used to destroy the flue gas from the first carbonization process, here thermal oxidizer 133. Therefore, even if the heat input from the flue gas from the second carbonization process is insufficient (flow rate too low) to maintain the oxidizer at its operating temperature, this will not be a problem because the oxidizer has already been sufficiently heated by the heat input from the flue gas from the first carbonization process. Preferably, the flue gas is entrained by flushing the treatment chamber of the furnace with a neutral gas, such as nitrogen.

[0061] The suction and discharge pipes of both furnaces should ideally be maintained at a temperature above 350°C to prevent the formation of deposits in the suction and / or discharge pipes. This can be achieved by insulating and / or heating the suction and discharge pipes.

[0062] At the outlet of the processing chamber 240 of the second furnace 200, i.e., after the second carbonization process, the loading component 300 passes through the cooling unit 260, which accelerates the cooling of the preform (step S90). The cooling unit is configured to allow the preform to leave to the open at a temperature below 300°C to prevent oxidation of the preform.

[0063] Upon leaving the cooling unit, the loading component 300 is transferred to the third sealing airlock 40 (step S100), where the first movable door 41 is open and the second movable door 42 is closed.

[0064] The first movable door 41 of the sealed airlock 40 is closed, and then the second movable door 42 is opened, which allows the load 300 to be brought to the open air via the loading device 50 in this example (step S110).

[0065] Starting from step S10, which introduces the preform loading component into the first sealing airlock, steps S10 to S110 are performed sequentially for each preform loading component. Steps S20 to S100 can be fully automated. The preform loading (step S10) and unloading (step S110) steps in the heat treatment plant can also be automated. Therefore, by introducing the preform loading component into the first sealing airlock at regular intervals, the preforms made of carbon precursor materials can be continuously carbonized.

[0066] The process of manufacturing C / C material components continues by densifying the preform in this way (step S120). In a known manner, the preform can be densified, for example, by chemical vapor infiltration (CVI) to produce component blanks made of carbon-carbon (C / C) composite materials, i.e., component blanks comprising carbon fiber reinforcements densified from a carbon matrix.

[0067] Then, the component blanks are subjected to high-temperature treatment (step S130), which can be carried out as described above to carbonize the fiber preforms. The temperature conditions (maximum temperature and temperature rise gradient) in the first and second furnaces are suitable for high-temperature treatment.

[0068] The phrase "included between..." should be understood as including the boundary.

Claims

1. An industrial process for heat-treating a preform made of a carbon precursor material (350), the process comprising the following steps in a sequential manner: - A loading member (300) of one or more preforms made of carbon precursor material (350) is introduced (S10) into a first sealing gas valve (20), the first sealing gas valve being selectively connected to a first furnace (100); - Replace the air present in the first airlock with a neutral gas (S20); - Transfer the loading component (300) (S30) into the first furnace (100); - Each preform of the loading component is subjected to a first carbonization treatment (S40) in the first furnace (100). - The loading component (300) is transferred (S50) into a second sealing airlock (30), which is selectively connected to the first furnace (100) and the second furnace (200); - Evacuate the second sealing airlock (30) (S60); - Transfer the loading component (S70) into the second furnace (200); - Each preform of the loading component is subjected to a second carbonization treatment (S80) in the second furnace (200); - The loading component (300) is transferred (S100) into a third sealing airlock (40), which is selectively connected to the second furnace (200) and the open outlet.

2. The manufacturing process according to claim 1, characterized in that, A loading (300) of one or more carbon precursor material preforms (350) is introduced into the first sealing airlock (20) at a defined time interval.

3. The process according to claim 1 or 2, characterized in that, The flue gas released by each preform during the first and second treatments is burned in the same thermal oxidizer (133).

4. The process according to claim 3, characterized in that, The first furnace and the second furnace (100, 200) are flushed with neutral gas.

5. The process according to claim 4, characterized in that, At least the mass flow rate of the neutral gas in the first furnace (100) is determined as a function of the mass flow rate of the flue gas.

6. The process according to any one of claims 1 to 5, characterized in that, The second furnace (100, 300) is alternately connected to the first cold trap and the second cold trap, each of which is configured to condense the flue gas released by each preform during the second carbonization process. The process includes the step of cleaning the first cold trap when the second cold trap is connected to the second furnace, and vice versa.

7. The process according to any one of claims 1 to 6, characterized in that, During the first carbonization process and the second carbonization process, the loading component sequentially passes through multiple heating zones (Z1-Z6, Z7-Z6) respectively present in the first furnace and the second furnace (100, 200). 14 The heating temperature is the first heating zone (Z1, Z7) and the last heating zone (Z6, Z7) among the plurality of heating zones. 14 The temperature gradually increases from the maximum heating temperature between 0 and 100°C.

8. The process according to claim 7, characterized in that, During the first carbonization process, the highest heating temperature in the last heating zone (Z6) of the plurality of heating zones (Z1-Z6) is between 700°C and 1000°C, and wherein the temperature rise rate between the first heating zone and the last heating zone (Z6) of the plurality of heating zones is less than 400°C / h.

9. The process according to claim 7 or 8, characterized in that, During the second carbonization process, the plurality of heating zones (Z7-Z) 14 The last heating zone (Z) in 14 The highest heating temperature in the plurality of heating zones is between 1500°C and 2600°C, and wherein the first heating zone and the last heating zone (Z) of the plurality of heating zones 14 The temperature rise rate between ( ) is less than 1500℃ / h.

10. The process according to any one of claims 1 to 9, characterized in that, The process includes a step of cooling each preform of the load after the second carbonization step and before the step of transferring the load to the third sealing airlock (40).

11. A manufacturing process for a carbon-carbon composite material component, comprising the following steps: - The process according to any one of claims 1 to 10 is used to heat-treat a preform made of a carbon precursor material; - Densification of preforms using a carbon matrix to obtain component blanks; - High-temperature treatment of component blanks.

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