Method of forming part by inserting solid metal alloy into set of molds
By inserting solid metal alloys into the casting module and using directional solidification and heating systems, the safety and quality control problems of the casting process in the investment casting method are solved, and the efficient and safe formation of multi-material parts is achieved, and the operation process is simplified.
Patent Information
- Application Number
- CN202380081375.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Priority Date
- 2022-11-25
- Filing Date
- 2023-11-23
- Publication Date
- 2025-07-08
AI Technical Summary
The existing investment casting methods have safety risks and quality control problems in the casting process when forming metal parts, especially when forming dual-material parts, they require multiple castings and are complex in operation, and the casting conditions need to be independently optimized for each metal alloy.
Solid metal alloy is inserted into the casting module, and castings are formed by directional solidification to avoid casting steps. The directional solidification and heating system are used to control the liquefaction and curing process of the metal alloy to achieve the formation of multi-material parts.
Improves operating safety, simplifies the operation process, reduces the risk of contamination and leakage of liquid metal alloys, can form multi-material parts in a single furnace, controls the size and position of the joint area, and improves the quality and reliability of the parts.
Smart Images
Figure CN120282843A_ABST
Abstract
Description
Technical Field
[0001] The present disclosure relates to a method for forming a metal part by investment casting method.
[0002] This method is particularly suitable for forming blades of aircraft turbine engines. The formed blades can be bi-material. Background Art
[0003] Generally, the known methods for forming parts using investment casting method include pouring a liquid metal alloy into a sprue cup of a ceramic mold assembly. This step is usually carried out in a furnace. Then, the metal alloy fills one or more casting shells within the mold assembly. Next, the assembly is cooled to solidify the metal alloy, thereby forming a casting.
[0004] To improve the quality of the obtained parts, it is preferable to carry out the pouring under vacuum to avoid any unwanted reactions, such as oxidation of the liquid metal alloy. In addition, since each metal alloy has different properties (melting point, viscosity, density, etc.), it is necessary to optimize the pouring process independently for each metal alloy. Therefore, those skilled in the art understand that pouring is an important issue. For example, the pouring conditions can affect the scrap rate of the part to be formed.
[0005] In addition, in the known methods, pouring seems to be an obstacle to forming bi-material parts. In fact, to obtain a bi-material part, two pourings and two solidifications need to be carried out in a single furnace; however, it is not possible to pour two alloys into the same sprue cup.
[0006] One solution could be to replace the sprue cup after the first pouring, but replacing the sprue cup is a non-automated operation that requires operator intervention. However, performing such a replacement in a running furnace poses a considerable risk to the operator. In fact, the temperature of a running furnace can exceed 1000 °C. This also poses a risk to the furnace itself, because opening the furnace during operation can cause significant changes in the thermal characteristics of the furnace, which may lead to significant thermal gradients, thereby causing cracking of the mold assembly and leakage of the liquid metal alloy into the furnace.
[0007] Therefore, it can be understood that pouring itself is a step that poses significant risks both from the perspective of safety and the quality of the parts to be obtained.
[0008] Therefore, there is indeed a need to improve the method for forming parts using investment casting method to at least partially avoid the above-mentioned inherent drawbacks. Summary of the Invention
[0009] The present disclosure relates to a method of forming a casting in a casting module, the casting module including a plurality of casting molds formed by investment casting, each of the plurality of casting molds having a top, a middle portion, and a bottom, a pouring cup capable of accommodating liquid metal, a connecting ring connecting the pouring cup to each top of each of the plurality of casting molds, a downsprue connected to the pouring cup, and a plurality of grain selectors, each grain selector being connected to the bottom of one of the plurality of casting molds, the method including: inserting a solid first metal alloy into the module, liquefying the first alloy inserted into the module, and directionally solidifying the thus liquefied first alloy.
[0010] Therefore, this method does not require pouring. In fact, in this method, the solid metal alloy inserted into the casting module melts when the casting module is inserted into the furnace. Therefore, supplying the liquid metal alloy in the plurality of casting molds of the casting module does not require pouring, because the liquid metal alloy is directly obtained through the transformation of the solid metal alloy inserted into the casting module.
[0011] Therefore, this method is safer for the operator. In addition, handling solid metal alloy is simpler than handling liquid metal alloy, so the method is easier to implement. In addition, avoiding pouring can avoid the risk of contamination of the liquid metal alloy during the pouring process. Additionally, this allows reducing the force exerted by the liquid metal on the casting module and / or other components.
[0012] In addition, since the liquid metal alloy is directly formed in the casting module, the risk of operation errors, such as errors on the part of the operator, which may cause the liquid metal alloy to be accidentally poured into the furnace during the pouring step, is eliminated.
[0013] In some embodiments, the casting module further includes a set of main channels, each channel in the set of main channels connecting the downsprue to the grain selector.
[0014] In this configuration, the casting module allows filling the plurality of casting molds from the bottom. In particular, in this configuration, the liquid metal alloy can flow from the downsprue to the casting molds.
[0015] In some embodiments, the solid first metal alloy is a single-piece cylindrical ingot.
[0016] In the present application, the term "cylindrical" is understood in a mathematical sense. A cylinder is defined as the volume obtained by translating a closed contour along an axis. For example, the closed contour can be circular or square.
[0017] Using a cylindrical ingot is easy to calculate the volume of the liquefied metal alloy. In addition, this form of solid metal alloy is easier to insert into the module.
[0018] In some embodiments, a gap is provided between the solid-state metal alloy inserted into the casting mold assembly and the casting mold assembly.
[0019] Thus, this gap allows for compensation of the expansion caused by temperature effects before the metal alloy melts. Consequently, this reduces the stress applied to the casting mold assembly, thereby reducing the risk of leakage.
[0020] In some embodiments, the method further includes a previous step of assembling the casting mold assembly, in which a plurality of casting shells, pouring cups, connecting rings, downsprue tubes, and a plurality of grain selectors are assembled together; and in which the solid-state first metal alloy is inserted into the mold assembly during the previous assembly step.
[0021] In some embodiments, the first metal alloy is inserted into the downsprue tube.
[0022] In some embodiments, the first metal alloy is inserted into the connecting ring.
[0023] Inserting the solid-state metal alloy during the assembly step simplifies the integration of the first metal alloy with the mold assembly. Consequently, this saves time for the operator. In particular, from this perspective, inserting the first metal alloy into the connecting ring or the downsprue tube is particularly advantageous.
[0024] In some embodiments, the casting mold assembly further includes multiple sets of secondary channels, each channel in each set of secondary channels connecting the downsprue tube and an intermediate portion of the casting shell, a plurality of plugs defining a plurality of casting paths, and in which a plurality of solid-state metal alloys are inserted into the plurality of casting paths, the method sequentially including, for each of the plurality of metal alloys, selectively liquefying the metal alloy and then casting the metal alloy through a set of secondary channels into the plurality of casting shells and then solidifying the liquefied metal alloy, optionally directionally solidifying.
[0025] In such a configuration, multi-material parts can be obtained without resorting to pouring. Additionally, the method combines all of the previously mentioned advantages associated with inserting the solid-state metal alloy into the mold assembly. This configuration is particularly advantageous for forming multi-material turbine engine blades.
[0026] In the present disclosure, a "multi-material" part is a part that includes at least two portions made of two different materials. For example, a blade including two portions made of two different metal alloys is considered a "multi-material" part.
[0027] Furthermore, one of the main challenges in forming multi-material blades is the joint region between the different materials. In particular, controlling the size, location, and solidification of the joint region is a concern for those skilled in the art seeking to manufacture multi-material blades.
[0028] According to this aspect, multi-material parts can be obtained in a single furnace, ensuring good properties of the obtained parts, especially at the joint regions between different materials. In fact, inserting a solid-state metal alloy allows for more precise control of the volume of the liquid metal alloy injected into the casting mold shell.
[0029] In some embodiments, the casting mold assembly includes an upper stopper placed at the joint between the pouring cup and the downsprue, and wherein the method includes: pouring a liquid terminal metal alloy into the pouring cup such that the terminal metal alloy flows through a connecting ring into each of a plurality of casting mold shells, and solidifying the terminal metal alloy.
[0030] Depending on the circumstances, pouring is desirable depending on the metal alloy and / or part involved. Thus, this configuration allows for obtaining multi-material parts by pouring the terminal metal alloy. On the other hand, this configuration represents an alternative and / or complement for obtaining multi-material parts.
[0031] In some embodiments, the casting mold assembly includes a container that includes a heating system; and the method further includes inserting a solid terminal metal alloy into the container and liquefying the terminal metal alloy by the heating system.
[0032] In some embodiments, the container is attached to the pouring cup.
[0033] This configuration allows for obtaining multi-material parts while avoiding the drawbacks associated with pouring, while retaining the advantages associated with using a pouring cup. Furthermore, according to this embodiment, the casting of the terminal metal alloy is faster than the pouring of this alloy according to known methods.
[0034] In some embodiments, the container includes a metal film at the joint between the container and the pouring cup.
[0035] In this configuration, the sealing of the container is improved.
[0036] In some embodiments, the heating system applies a temperature gradient between 10°C and 50°C in the container, preferably 50°C.
[0037] In some embodiments, the heating system applies a temperature gradient between 10°C and 30°C.
[0038] Thus, this gradient allows for controlling the melting of the terminal metal alloy, especially for gradually liquefying it. This improves the casting reliability of the terminal metal alloy in the plurality of casting mold shells of the casting mold assembly.
[0039] In some configurations, a plurality of ceramic cores are provided in the plurality of casting mold shells.
[0040] The plurality of ceramic cores allows for greater diversity of parts. For example, this allows for the production of blades known as hollow or cooling blades.
[0041] The present disclosure also relates to a blade of a turbomachine obtained by a method according to any one of the foregoing embodiments.
[0042] In some configurations, the blade includes at least two portions made of two different metal alloys, and a joint region between these two portions.
[0043] The above features and advantages, as well as other features and advantages, will become apparent upon reading the following detailed description of the exemplary embodiments of the proposed device and method. This detailed description refers to the accompanying drawings.
[0044] Brief Description of the Drawings
[0045] The drawings are schematic and are mainly intended to illustrate the principles of the present disclosure.
[0046] Figure 1 A casting mold set according to a first embodiment of the present invention is schematically shown, in which a metal alloy is inserted into the bottom sprue.
[0047] Figure 2 A casting mold set according to Figure 1 an embodiment is schematically shown, which is arranged in a furnace, and in which the metal alloy is liquefied.
[0048] Figure 3 A casting mold set according to Figure 1 an embodiment is schematically shown, in which the liquid metal alloy is cast into a plurality of casting shells.
[0049] Figure 4 A casting mold set according to Figure 1 an embodiment is schematically shown, in which the metal alloy is solidified.
[0050] Figure 5 A casting mold set according to Figure 1 an embodiment is schematically shown, in which the terminal metal alloy is poured into the pouring cup.
[0051] Figure 6 A casting mold set according to Figure 1 an embodiment is schematically shown, in which the terminal metal alloy is solidified.
[0052] Figure 7 A casting mold set according to a second embodiment of the present invention is schematically shown, in which a plurality of metal alloys are inserted into the bottom sprue.
[0053] Figure 8 A casting mold set according to a third embodiment of the present invention is schematically shown, in which the terminal alloy is inserted into a container.
[0054] Figure 9Schematically shows a casting module according to the third embodiment, in which a first metal alloy is liquefied and cast into a plurality of casting shells.
[0055] Figure 10 Schematically shows a casting module according to the third embodiment, in which a terminal alloy is liquefied.
[0056] Figure 11 Schematically shows a casting module according to the third embodiment, in which the terminal alloy is poured into a pouring cup.
[0057] Figure 12 Schematically shows a fourth embodiment, in which a first metal alloy is stored in a solid state in the upper part of the casting module.
[0058] Embodiment description
[0059] To make the present disclosure more specific, examples of the device are described in detail below with reference to the accompanying drawings. It should be noted that the present invention is not limited to this example.
[0060] Figure 1 Schematically shows a casting module 100 according to the first embodiment of the present invention. The casting module 100 includes a pouring cup 101 configured to accommodate liquid metal, a connecting ring 102, a plurality of casting shells 103, a grain selector 104, a set of main channels 105, and a downsprue 106 connected to the pouring cup 101. Each channel in the set of main channels 105 connects the downsprue 106 to the grain selector 104.
[0061] The plurality of casting shells 103 include casting shells formed by the investment casting method, and each casting shell in the plurality of casting shells 103 has a top, a middle part, and a bottom.
[0062] The connecting ring 102 connects the pouring cup 101 to each top 103a of each casting shell in the plurality of casting shells 103, and each grain selector in the plurality of grain selectors 104 is connected to the bottom 103c of one casting shell in the plurality of casting shells 103. Advantageously, the plurality of casting shells 103 may include a plurality of cores to obtain, for example, hollow blades.
[0063] In this example, a ceramic stopper 107 may be provided at the joint between the pouring cup 101 and the downsprue 106. The stopper is impermeable to liquid metal, thereby forcing the liquid metal poured into the pouring cup 101 to flow into the connecting ring 102 and then into the plurality of casting shells 103. When the liquid metal flows along such a path, this is called drop-type liquid metal casting.
[0064] The first metal alloy 10 is inserted into the downsprue 106. The first metal alloy 10 is inserted in the form of a single-piece cylindrical ingot having a circular bottom. In other examples, the first metal alloy 10 can be inserted into a connecting ring. Additionally, the first metal alloy 10 can be inserted in particulate form or any other suitable solid state form for insertion into the mold unit 100.
[0065] In this example, the downsprue 106 is cylindrical with a circular bottom. A gap d is provided between the inner wall of the downsprue 106 and the first metal alloy 10.
[0066] Figure 2 The casting mold unit 100 of the first embodiment disposed in the Birdgman furnace 50 is shown. The furnace 50 includes a hot zone 51 and a cold zone 52. Initially, the casting mold unit 100 is placed at the hot zone 51 of the furnace 50. The first metal alloy 10 liquefies.
[0067] The volume of the liquefied metal alloy 10 is calculated according to the following formula.
[0068] [Mathematical formula 1]
[0069]
[0070] Wherein, V S is the volume of the solid state metal alloy, V L is the volume of the liquid state metal alloy, ρ S is the density of the solid state metal alloy, ρ L is the density of the liquid state metal alloy. Generally, for nickel alloys, the density ratio is about 1.14.
[0071] Knowing the volume of the plurality of casting shells 103 to be filled, the amount or volume of the metal alloy 10 to be provided to fill the plurality of casting shells 103 can be derived. The inventors have found that it is necessary to provide a solid state metal alloy slightly more than the volume required to fill the plurality of casting shells 103 to compensate for the remaining volume lost due to the shrinkage of the metal alloy during the solidification of the metal alloy.
[0072] As Figure 3 shown, the first molten metal alloy 10 fills the plurality of casting shells 103 through the bottom 103c of the casting shell along the channel group 105. For example, such filling can be carried out only by gravity and / or capillary action. When the liquid metal flows along such a path, this is called bottom casting of the metal alloy.
[0073] In this example, the first metal alloy 10 partially fills the plurality of casting shells 103. However, in other examples, the first metal alloy 10 can completely fill the plurality of casting shells 10, as long as a sufficient volume is provided.
[0074] As Figure 4As shown, once the first metal alloy 10 is cast into a plurality of casting shells 103, the casting module is transferred (e.g., by the downward gravitational pull of the casting module or under the action of an actuating member such as a jack) to the cold zone 52 of the casting shell, such that the first liquid metal alloy 10 is located in the cold zone 52 of the furnace 50. In this example, only the partially filled portions of the plurality of casting shells 103 are located in the cold zone 52 of the furnace 50.
[0075] Accordingly, the first metal alloy 10 crystallizes in the plurality of casting shells 103. In this example, the solidification of the first metal alloy 10 is directed by a plurality of grain selectors 104. In other words, the first metal alloy 10 crystallizes as a plurality of single crystal alloys in the plurality of casting shells 103.
[0076] In this example, after the first metal alloy 10 has crystallized, a liquid terminal metal alloy 20 ( Figure 5 ) different from the first metal alloy 10 is poured into the pouring cup 101. Due to the upper stopper 107, the casting of the terminal metal alloy 20 is a drop type.
[0077] The terminal metal alloy 20 flows into the plurality of casting shells 103 and fills the empty spaces left by the first metal alloy 10. An interface 12 is formed between the first metal alloy 10 and the terminal metal alloy 20. At this interface, diffusion of the terminal metal alloy 20 into the first metal alloy 10 can be observed. In addition, during the pouring of the terminal metal alloy 20, partial remelting of the first metal alloy 10 at the interface 12 can be observed.
[0078] Once the terminal metal alloy 20 is poured, as Figure 6 shown, the entire casting module 100 is transferred (e.g., by the downward gravitational pull of the casting module or under the action of an actuating member such as a jack) to the cold zone 52 of the casting shell 50. Thus, the terminal metal alloy 20 solidifies. Optionally, the first metal alloy 10 can be used as a seed for the directional solidification of the terminal metal alloy 20.
[0079] Once the terminal metal alloy 20 has solidified, a plurality of parts are obtained in the plurality of casting shells. Different finishing steps for the plurality of parts can be provided.
[0080] Figure 7 The casting module 100 according to a second embodiment compatible with the first embodiment is shown. In the example of the second embodiment, the casting module 100 includes a plurality of stoppers 107' arranged in the lower pouring tube 106. In addition, the casting module 100 includes a plurality of sets of secondary channels 105', and each channel in each set of secondary channels 105' connects the lower pouring tube 106 and an intermediate portion 103b of one of the plurality of casting shells 103.
[0081] In this way, a plurality of cavities are formed between each of the plurality of plugs 107' in the downsprue 106. The channels of the plurality of sets of secondary channels 105' are configured to connect each of these cavities to different casting molds 103 of the plurality of casting molds. Therefore, a plurality of casting paths are formed in the downsprue 106.
[0082] A plurality of different metal alloys 10' are inserted into the plurality of cavities formed between the plugs 107. For example, the plugs 107 can be inserted during the assembly of the casting mold set. Advantageously, each of the plurality of metal alloys 10' has a different melting point. Therefore, once the casting mold set 100 is placed in the furnace 50, the metal alloys in the plurality of metal alloys 10' can be selectively liquefied by appropriately controlling the temperature of the hot zone 51 of the furnace 50.
[0083] When one of the plurality of alloys 10' is liquefied, it is cast into and solidified in the casting mold of the plurality of casting molds 103 in a manner similar to the casting and solidification of the first metal alloy 10. Therefore, the liquefied first alloy is bottom-cast.
[0084] In this case, a multi-material part can be obtained by selectively liquefying and then solidifying the metal alloys in the plurality of metal alloys 10'.
[0085] Figure 8 A casting mold set 100 of a third embodiment compatible with other embodiments is shown. The casting mold set 100 of the third embodiment is the same as the casting mold set 100 of the first embodiment in all aspects except for the container 200 and the heating system 202 described below. In addition, the method for obtaining parts of this third embodiment is the same as that of the first embodiment except for the pouring of the terminal metal alloy 20.
[0086] In the third embodiment, the casting mold set 100 includes a container 200 and a heating system 202 capable of heating the container 200. For example, the heating system 202 can be a heating resistor. The container 200 can be attached to the pouring cup 101. Alternatively, the container 200 can be attached by other means not shown and is disposed above the pouring cup 101 such that the liquid flowing out of the container 200 under the action of gravity falls into the pouring cup 101.
[0087] A metal film 204 usually made of nickel can be provided at the joint between the container 200 and the pouring cup 101.
[0088] In this example, the terminal alloy 20 is inserted into the container 200 in a solid state.
[0089] As Figure 9 shown, the first metal alloy 10 is liquefied and then solidified as described in the first embodiment. After this solidification, as Figure 10As shown, the heating system 200 liquefies the terminal metal alloy 20. In other examples, the furnace 50 is capable of liquefying the terminal metal alloy 20.
[0090] As Figure 11 shown, once the terminal metal alloy 20 is liquefied, the metal film 204 is removed, and the liquid terminal metal alloy 20 is poured into the sprue cup 101. Then, the terminal metal alloy 20 solidifies in a manner similar to the first embodiment.
[0091] The removal of the metal film 204 can be achieved by melting the latter. In fact, once the terminal metal alloy 20 is liquefied, the terminal metal alloy 20 is capable of melting the metal film 204.
[0092] Alternatively, the container 200 may include a bottom instead of the metal film 204. In addition, the bottom includes an opening facing the sprue cup 101. The terminal metal alloy may have a cylindrical shape, and the characteristic dimension of its bottom is larger than the characteristic dimension of the opening of the container 200. In this case, when the terminal metal alloy 20 is inserted into the container 200 in solid form, the terminal metal alloy 20 is held in a fixed vertical position in the container. However, when the terminal metal alloy 20 is liquefied, it can be poured into the sprue cup 101 of the casting mold set 100 through the opening of the container 200.
[0093] Optionally, the heating system can apply a temperature gradient in the container 200. In this case, the terminal metal alloy 20 can be partially liquefied. This reduces the risk of the appearance of non-liquefied solid particles. Such particles are undesirable because they can impair the performance of the part to be formed. These particles are even more undesirable because they may block, for example, the channels of the casting mold set 100.
[0094] As Figure 12 schematically shown, a casting mold set 300 similar to Figure 1 the casting mold set 100 of Figure 1 shown, in addition to the components with the same reference numerals 101, 103, 103a–b, 104, 105, 106, and 107 as shown in
[0095] more specifically, this area includes a plurality of storage containers or cylindrical containers 310, which are respectively arranged above the casting shell 103, and each is connected to the casting shell (top 103a) through a vertical connector 312. Each of the cylindrical containers 310 contains the first metal alloy 314 in solid form, for example, in the form of ingots (e.g., a single-piece cylindrical shape with a circular bottom), or in particulate form or any other solid form. The first alloy has been previously inserted into the mold set.
[0096] The connecting ring 302 connects the lower part of the pouring cup 101 to the upper part of the cylindrical container 310, and the plug 107 is positioned at the upper part of the downsprue 106 so that the material (second alloy) present in the pouring cup can be directly distributed into the cylindrical container without passing through the downsprue.
[0097] In this embodiment, the downsprue 106 is not used. Thus, the method described herein can be used in a mold set configuration that does not include a downsprue.
[0098] In this embodiment, the mold set 300 is introduced into the hot zone 51 of the furnace 50 in the Figure 2 manner shown, and the first alloy 314 is liquefied within the cylindrical container 310, which allows it to flow directly from each cylindrical container 310 through the connecting member 312 into the lower casting shell (drop filling method). As compared with the Figure 1 configuration of the mold set 100, the configuration of the mold set 300 is advantageous because the storage area of the first metal alloy 314 is arranged as close as possible to the heating element and / or radiation wall of the furnace (at the periphery of the mold set rather than in the center as in the downsprue 106). Thus, the storage area of the first metal alloy 314 is not blocked by the components of the mold set between the assembly and the heating element and / or radiation wall of the furnace and is thus directly exposed to the heating radiation. This results in higher operating efficiency.
[0099] As Figure 4 shown, the mold set 300 is then vertically lowered partially into the cold zone 52 of the furnace 50 to solidify the first metal alloy 314.
[0100] As Figure 5 shown, after the first metal alloy has crystallized, a liquid terminal metal alloy (second alloy) different from the first metal alloy is poured into the pouring cup 101. Due to the upper plug 107, the casting of the terminal metal alloy is by dropping and is distributed in the connecting ring 302 up to the cylindrical container 310, and the terminal metal alloy flows in the cylindrical container 310 to reach the plurality of casting shells 103 through the connecting member 312 and fill the empty spaces left by the first metal alloy 314 therein. The remainder of the description of the first mode applies here and will not be repeated.
[0101] Although the present invention has been described with reference to specific exemplary embodiments, it is obvious that modifications and changes can be made to these examples without departing from the overall scope of the invention as defined by the claims. In particular, the individual features of the various illustrated / mentioned embodiments can be combined in additional embodiments. Thus, the specification and drawings should be regarded as exemplary rather than restrictive.
[0102] Obviously, all features described in the reference method can be transferred to the apparatus, either individually or in combination, and vice versa, all features described in the reference apparatus can be transferred to the method, either individually or in combination.
Claims
1. A method of forming a casting in a casting mold assembly (100), the casting mold assembly (100) comprising: · A plurality of casting shells (103) formed by the investment casting method, each of the plurality of casting shells (103) having a top, a middle portion, and a bottom, · A sprue basin (101) capable of accommodating liquid metal, · Connect the sprue cup (101) to the connecting ring (102) at the top of each of the plurality of casting shells (103). · The tundish well (106) connected to the pouring cup, · A plurality of grain selectors (104), each grain selector being connected to the bottom of one of the plurality of casting shells (103), · The method includes: · Insert the solid first metal alloy (10) into the module (100). · Liquefy the first alloy (10) inserted into the module (100), · The thus liquefied first alloy (10) is directionally solidified.
2. The method according to claim 1, wherein the casting mold assembly (100) further comprises a set of main channels (105), each channel in the set of main channels (105) connecting the bottom sprue (106) to the grain selector (104).
3. The method according to claim 1 or 2, wherein the first metal alloy (10) in solid state is a single-piece cylindrical ingot.
4. The method according to any one of claims 1 to 3, further comprising a previous step of assembling the casting mold assembly (100), wherein the plurality of casting shells (103), the pouring cup (101), the connecting ring (102), the bottom sprue (106) and the plurality of grain selectors (104) are assembled together; and wherein the first metal alloy (10) in solid state is inserted into the casting mold assembly (100) in the previous assembling step.
5. The method according to any one of claims 1 to 4, wherein the casting mold assembly (100) further comprises: · Multiple sets of secondary channels (105'), each channel in each set of secondary channels (105') connecting the bottom pouring tube (106) and the middle part of the casting shell (103). · A plurality of plugs (107'), defining a plurality of casting paths, and wherein a plurality of solid metal alloys (10') are inserted into the plurality of casting paths, and for each of the plurality of metal alloys (10'), the method sequentially comprises: · Optionally liquefy the metal alloy, · Then, the metal alloy is cast into the plurality of casting shells (103) in one of the plurality of secondary channels (105'). · Then solidify the liquefied metal alloy.
6. The method according to any one of claims 1 to 5, wherein the casting mold assembly (100) comprises an upper plug (107) disposed at the junction between the pouring cup (101) and the bottom sprue (106), and wherein the method comprises: · Pour the liquid terminal metal alloy (20) into the pouring cup (101) so that the terminal metal alloy (20) flows into each of the plurality of casting shells (103) through the connecting ring (102). · Solidify the terminal metal alloy (20).
7. The method according to claim 6, wherein the casting mold assembly (100) comprises a container (200), the container (200) comprising a heating system (202); and the method further comprises: · Insert the solid terminal metal alloy (20) into the container (200). · Liquefy the terminal metal alloy (20) through the heating system (202).
8. The method according to claim 7, wherein the container (200) comprises a metal film (204) at the junction between the container (200) and the pouring cup (101).
9. The method according to claim 7 or 8, wherein the heating system applies a temperature gradient between 10 °C and 50 °C in the container.
10. The method according to any one of claims 1 to 9, wherein a plurality of ceramic cores are provided in the plurality of casting shells.
11. A turbine engine blade obtained by the method according to any one of the preceding claims.
12. The blade according to claim 11, comprising at least two parts made of two different metal alloys, and a joint region (12) between the two parts.