A multi-connection single crystal blade and a method for manufacturing the same

Abstract

The application discloses a kind of multi-union single crystal blade and preparation method thereof, blade trial production stage, multiple blade wax mould is positioned and assembled one by one, the thickness of gasket in joint is adjusted, so that the spacing of adjacent blade wax mould meets design requirements, and multiple blade wax mould is connected into one by pouring wax in joint, shell is made using the above-mentioned multi-union blade wax mould, and multiple blade castings are obtained by pouring shell, the actual spacing of adjacent blades is determined by size detection, and blade batch production stage, the thickness of gasket is adjusted according to the difference between actual spacing of blade and design requirement spacing, the adjustment value of gasket thickness is equal to the difference between actual spacing of blade and design requirement spacing, then multiple blade wax mould is positioned and assembled one by one, and the gasket after adjustment is padded in the joint of adjacent blade wax mould, and finally, the multi-union single crystal blade castings with spacing meeting design requirements are prepared using the multi-union blade wax mould after adjusting spacing.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of single crystal precision casting, and particularly relates to a multi-connection single crystal blade and a preparation method thereof BACKGROUND

[0002] The multi-connection single crystal blade part requires high precision, and the multi-connection single crystal blade is prone to deformation. Due to the complex structure of the part, the overall mold opening cost is high, and it is difficult to take the mold, so a single blade mold is usually designed, and a plurality of blades are spliced and combined through a tool. Since the blade solidification shrinkage process is a relatively complex process, affected by various factors, the shrinkage rates of the single blades are not completely the same, thus causing a deviation between the spacings of the blades and the designed spacings. SUMMARY

[0003] The main purpose of the application is to provide a multi-connection single crystal blade and a preparation method thereof, and to obtain a multi-connection single crystal blade casting with a spacing meeting the design requirements.

[0004] To this end, the multi-connection single crystal blade preparation method provided by an embodiment of the application comprises the following steps.

[0005] Blade trial production stage:

[0006] The plurality of blade wax molds are sequentially positioned and spliced

[0007] During the splicing of the blade wax molds, the thickness of the gasket in the splicing joint is adjusted to make the spacing between the adjacent blade wax molds meet the design requirements, and the plurality of blade wax molds are connected into one by pouring wax liquid into the splicing joint; then the gasket is pulled out, and the space left by the gasket is filled with the wax liquid;

[0008] The mold shell is made by using the above multi-connection blade wax mold, the casting is obtained by pouring the mold shell, the size of the casting is detected, and the actual spacing of the adjacent blades is determined;

[0009] Blade mass production stage:

[0010] The thickness of the gasket is adjusted according to the difference between the actual spacing of the blade and the design spacing, and the adjustment value of the thickness of the gasket is equal to the difference between the actual spacing of the blade and the design spacing;

[0011] Then the plurality of blade wax molds are sequentially positioned and spliced, the adjusted gasket is arranged in the splicing joint between the adjacent blade wax molds, the splicing joint is filled with the wax liquid, after the wax liquid solidifies, the gasket is pulled out, and the space left by the gasket is filled with the wax liquid, and finally the multi-connection single crystal blade is prepared by using the multi-connection blade wax mold with the adjusted spacing.

[0012] Specifically, the chill plate of the directional solidification furnace is designed to be tiltable, when the assembled multiple-leaf blade wax mould is combined with the spiral selector wax mould, the spiral selector wax mould is connected to the corner of the lower edge plate of the blade wax mould and the axial directions of the two are kept parallel, the corresponding corners of the upper and lower edge plates of the blade wax mould are connected through the seed guiding strip, during directional solidification, the seed generating end of the spiral selector is vertically installed on the chill plate, with the chill plate continuously horizontally descending in the cold chamber of the directional solidification furnace, the single crystal vertically grows in the spiral selector and is parallel to the axial direction of the blade, when the single crystal grows to the transition section of the spiral selector and the lower edge plate of the blade, the chill plate and the blade mould shell are slowly adjusted to be tiltable, and then are descended at the designed speed, so that the sequential solidification of the edge plate of the blade is ensured, and the generation of mixed crystals at the corner of the edge plate and the generation of loose on the surface of the edge plate are avoided.

[0013] Specifically, the tilting angle θ of the chill plate is dynamically adjusted according to the position change of the solidification interface, and the specific adjustment process is as follows:

[0014] During the process that the solidification interface moves from the transition section of the spiral selector and the lower edge plate of the blade to the lower end of the upper edge plate of the blade, the tilting angle θ of the chill plate is continuously adjusted, the tilting angle α1 of the tangent line of the lower edge plate of the blade is kept greater than or equal to 30°, and the tilting angle β of the seed guiding strip below the edge plate of the blade is kept greater than or equal to 30°;

[0015] During the process that the solidification interface moves from the lower end of the upper edge plate of the blade to the upper end of the lower edge plate of the blade, the tilting angle θ of the chill plate is continuously adjusted, the tilting angle α1 of the tangent line of the lower edge plate of the blade is kept greater than or equal to 30°, and the tilting angle α2 of the tangent line of the upper edge plate of the blade is kept greater than or equal to 30°;

[0016] During the process that the solidification interface moves from the upper end of the lower edge plate of the blade to the completion of the solidification of the whole blade, the tilting angle θ of the chill plate is continuously adjusted, and the tilting angle α2 of the tangent line of the upper edge plate of the blade is kept greater than or equal to 30°.

[0017] Specifically, the chill plate is a copper water-cooled plate.

[0018] Specifically, the directional solidification furnace is a vacuum furnace.

[0019] Another aspect of the embodiment of the present application provides a multiple-leaf single crystal blade prepared by the multiple-leaf single crystal blade preparation method.

[0020] Compared with the prior art, at least one embodiment of the present application has the following beneficial effects: by designing a single-leaf mould, when the blade is trial-produced, multiple blade wax moulds are combined and spacers are padded in the joint seams to make the spacing of the adjacent blade wax moulds meet the design requirements, then the castings are poured and the castings are dissected to determine the actual spacing of the adjacent blades, when the blades are mass-produced, the thickness of the spacers in the joint seams of the blade wax moulds is adjusted to make compensation according to the difference between the actual spacing of the blades determined during the trial production and the design required spacing, so that the spacing of the multiple-leaf single crystal blade castings prepared subsequently meets the design requirements. Attached Figure Description

[0021] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0022] Figure 1 This is a schematic diagram of the positioning fixture structure for assembling multi-blade wax molds according to an embodiment of the present invention;

[0023] Figure 2 This is a schematic diagram of the solidification interface located at the transition section before the quench plate is adjusted, according to an embodiment of the present invention.

[0024] Figure 3 This is a schematic diagram of the solidification interface located at the transition section after the quench plate is tilted and adjusted according to an embodiment of the present invention.

[0025] Figure 4 This is a schematic diagram of the quench plate adjustment when the solidification interface passes through the upper and lower edge plates of the multi-blade assembly, as described in an embodiment of the present invention.

[0026] Figure 5 This is a schematic diagram of the adjustment of the quench plate at the end of solidification of the lower edge plate of the blade according to an embodiment of the present invention;

[0027] Figure 6 This is a schematic diagram of the adjustment of the quench plate when the upper edge plate of the blade is solidified at the end of the embodiment of the present invention;

[0028] Figure 7 This is a schematic diagram of the blade casting after all solidification and quenching plates have been reset, according to an embodiment of the present invention. Detailed Implementation

[0029] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0030] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0031] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified.

[0032] A method for preparing multi-unit single-crystal blades includes the following:

[0033] Blade prototype manufacturing stage:

[0034] Multiple leaf wax models were positioned and assembled one by one.

[0035] During the assembly of blade wax models, the thickness of the shims in the splicing seams is adjusted to ensure that the spacing between adjacent blade wax models meets the design requirements. Multiple blade wax models are then connected as one unit by injecting wax liquid into the splicing seams. Afterward, the shims are removed, and the space left by the shims is filled with wax liquid.

[0036] The above-mentioned wax mold is used to make a mold shell, the mold shell is poured to obtain a casting, the dimensions of the casting are checked, and the actual spacing between adjacent blades is determined.

[0037] Blade mass production stage:

[0038] Based on the difference between the actual blade spacing and the design spacing, the thickness of the shims is adjusted. The adjusted shim thickness is equal to the difference between the actual blade spacing and the design spacing. Then, multiple blade wax models are positioned and assembled one by one. The adjusted shims are placed in the joints between adjacent blade wax models. The joints are filled with wax liquid. After the wax liquid solidifies, the shims are removed, and the space left by the shims is filled with wax liquid. Finally, the multi-unit single crystal blades are prepared using the multi-unit blade wax models with adjusted spacing.

[0039] In this embodiment, by designing a single-blade mold, multiple blade wax models are spliced ​​together, and shims are inserted into the splicing seams to adjust the blade spacing. During blade trial production, shims are inserted into the splicing seams to ensure that the spacing between adjacent blade wax models meets the design requirements. After casting, the casting is dissected to determine the actual spacing between adjacent blades. Then, based on the difference between the actual blade spacing and the design requirement spacing, the thickness of the shims in the splicing seams of the multi-blade wax models is adjusted to compensate, so that the spacing of the multi-blade single-crystal castings produced in subsequent mass production meets the design requirements.

[0040] See Figure 1 Specifically, during the positioning and assembly of the blade wax models, two individual blade wax models 1 are first placed side by side on the base 201 of the positioning fixture 2, and the shim 3 is placed between the joint 4 of the two blade wax models 1. The planar positioning block 202 on the base 201 ensures that the two blade wax models 1 are aligned vertically. Then, the front ends of the upper edge plates of the two blade wax models 1 are respectively abutted against the corresponding arc-shaped positioning blocks 203 on the base 201, so that the blade wax models 1 are aligned front-backly. Then, the two blade wax models 1 are held in place by clamps or by hand, so that the two blade wax models 1 are aligned with the shim in the middle. Clamp the pad 3, then fill the joint 4 with wax liquid to connect the two blade wax models into one. Then move one blade wax model to the position and repeat the above steps to splice all the blade wax models together. To facilitate the insertion and removal of the pad 3, a pad fixing support 5 is provided on the base 201. The pad 3 is clamped by the clamping plate 6. The pad fixing support 5 is provided with a channel for the clamping plate 6 to pass through. The tail end of the clamping plate 6 is also provided with a limiting block 7 to limit the insertion depth of the clamping plate 6. By inserting the clamping plate 6 into the channel, the pad 3 can be inserted from between the two arc-shaped positioning blocks 203 into the joint 4 of the two blade wax models 1.

[0041] In some embodiments, the quench plate of the directional solidification furnace is designed to be tiltable. When the assembled multi-blade wax mold is combined with the spiral crystal selector wax mold, the spiral crystal selector wax mold is connected to the corner of the lower edge plate of the blade wax mold, and the axes of the two are kept parallel. The corresponding corners of the upper and lower edge plates of the blade wax mold are connected by crystal guide strips. During directional solidification, the crystal-starting end of the spiral crystal selector is vertically installed on the quench plate. As the quench plate descends horizontally in the cold chamber of the directional solidification furnace, single crystals parallel to the blade axis grow vertically in the spiral crystal selector. When the single crystal grows to the transition section between the spiral crystal selector and the lower edge plate of the blade, the quench plate and the blade mold shell are slowly adjusted to tilt and then descended at the designed speed to ensure the sequential solidification of the blade edge plates and avoid the generation of impurities at the edge plate corners and the loosening of the edge plate surface.

[0042] In this embodiment, the starting end of the spiral crystal selector is vertically mounted on the quench plate, allowing the heat flow Q in the molten metal to enter the quench plate vertically. Since the quench plate is horizontally set in the cold chamber of the directional solidification furnace, the heat flow Q in the molten metal is parallel to the temperature change direction in the cold chamber. This allows the molten metal to first solidify vertically, with the

[001] crystal orientation as the preferred direction, and the grains grow vertically upward in the opposite direction to the heat flow Q. Then, the quench plate drives the blade mold shell to tilt. As the quench plate continues to descend, the solidification of the single crystal extends to the entire blade. At this point, although the macroscopic solidification direction of the molten metal is no longer parallel to the blade axis, the crystal orientation of the grown single crystal remains unchanged. That is, the axis of the single crystal blade remains parallel to the

[001] crystal orientation of the single crystal. In addition, the tilting of the mold shell ensures the sequential solidification of the blade edge plates, avoiding the generation of impurities at the edge plate corners and the formation of porosity on the edge plate surface.

[0043] The blade to be prepared in this embodiment is a multi-unit integral casting guide blade with a large arc edge plate. For this guide blade, since the edge plate is not only wider, but also has a significantly larger arc, in order to ensure that no impurities appear during the solidification process, the tilt angle θ of the quench plate must be continuously and dynamically adjusted according to the position of the solidification interface. This results in the continuous adjustment of the tilt angles α1 and α2 of the tangents of the upper and lower edge plates and the tilt angle β of the crystal guide strip, so as to achieve the purpose of obtaining a single crystal guide casting with crystal orientation parallel to the blade main axis and no impurities and loose edge plate.

[0044] The specific process of dynamically adjusting the tilt angle θ of the chiller plate is as follows;

[0045] During the process of the solidification interface moving from the transition section between the spiral crystal selector and the lower edge plate of the blade to the lower end of the upper edge plate of the blade, the tilt angle of the quench plate is adjusted by the drive system of the directional solidification furnace so that the tilt angle α1 of the tangent of the lower edge plate of the blade is ≥30°, while ensuring that the tilt angle β of the crystal guide strip below the blade edge plate is ≥30°.

[0046] During the process of the solidification interface moving from the lower end of the upper edge plate of the blade to the upper end of the lower edge plate of the blade, the tilt angle of the quench plate is adjusted so that the tilt angle α1 of the tangent of the lower edge plate of the blade is ≥30°, while ensuring that the tilt angle α2 of the tangent of the upper edge plate of the blade is ≥30°.

[0047] During the solidification process from the upper edge of the blade's lower edge plate to the completion of the entire blade's solidification, the tilt angle of the quench plate is adjusted so that the tilt angle α2 of the tangent of the blade's upper edge plate is ≥30°.

[0048] The specific process of the above-mentioned precision casting method for single-crystal guide vanes is as follows:

[0049] During production, the blade wax mold and the spiral crystal selector wax mold are first pressed out. The spiral crystal selector is then bonded to one corner of the blade wax mold edge plate, and the axis of the crystal selector is kept parallel to the axis of the blade body. The blade wax mold and the pouring cup wax mold are then connected to form a wax tree.

[0050] In the wax tree, thin wax strips are used to connect the corresponding corners of the upper and lower edge plates as crystal guides and shrinkage compensation strips. This serves to guide the single crystal growth of the lower edge plate to the upper edge plate, prevent the formation of impurities at the corners of the upper edge plate due to overcooling, and compensate for the shrinkage at the corners of the lower edge plate during solidification, preventing porosity defects. Additionally, ceramic rods are used to connect the cantilevered ends of the edge plates to the base plate to form support pillars.

[0051] The assembled wax mold is repeatedly dipped in slurry and sanded, and finally dewaxed and sintered to produce the corresponding blade mold shell.

[0052] The blade mold is vertically installed on the tiltable quench plate on the lifting platform of the directional solidification furnace. The blade mold is then raised to the hot chamber of the directional solidification furnace. The furnace door is closed and a vacuum is drawn. Power is then applied to preheat the blade mold.

[0053] The high-temperature alloy ingot in the crucible above the hot chamber is induction melted and superheated, then poured into the pouring cup of the blade mold shell. The molten metal enters the inner cavity of the mold shell and comes into contact with the upper surface of the chiller plate through the spiral crystal selector, generating a chilled solidification layer that grows upwards (e.g., Figure 2 (As shown).

[0054] As the quench plate slowly descends horizontally, the blade mold shell enters the cold chamber of the directional solidification furnace. The heat flow Q from the molten metal enters the quench plate vertically. Grains with the

[001] crystal orientation as their preferred direction grow vertically upwards in the opposite direction to the heat flow Q. Individual grains are selected by a crystal selector and continue growing to the transition section between the crystal selector and the lower edge plate of the blade (e.g., ...). Figure 2 As shown in the figure, the solidification interface is located at the transition section between the spiral crystal selector and the lower edge plate of the blade. At this time, the

[001] crystal orientation in the crystal is vertical and parallel to the main axis of the blade.

[0055] Before reaching the lower edge plate of the blade, but before entering the transition section between the spiral crystal selector and the lower edge plate at the solidification front, the tiltable quench plate is slowly tilted (tilt angle θ) by the drive system, so that the tilt angle α1 of the bottom tangent of the lower edge plate increases from α0 to α1≥30°. Figure 3 At the same time, ensure that the tilt angle β of the crystal guide strip below the edge plate is ≥30°.

[0056] As the mold shell descends, the solidification interface enters the lower edge plate and continues to solidify obliquely upwards. θ is continuously adjusted to maintain α1 ≥ 30°, while ensuring the tilt angle β of the crystal guide strip below the edge plate is ≥ 30°, until the solidification interface enters the lower end of the upper edge plate. The mold shell continues to descend, and the solidification interface simultaneously enters the upper edge plate and continues to solidify obliquely upwards. Figure 4 ), continuously adjust θ, keeping α1 ≥ 30°, until the lower edge plate has solidified. Figure 5During this process, it is important to maintain the tilt angle α2 of the upper edge plate tangent ≥ 30°. Generally, as long as the tilt angle α1 of the lower edge plate tangent is controlled to be > 30°, the tilt angle of the upper edge plate tangent will naturally satisfy the condition α2 > 30°. In this stage, because the crystal guide strip and adjacent blades have already solidified, although the tilt angle β decreases and does not satisfy β ≥ 30°, no more impurities will appear.

[0057] Continue lowering the shell while adjusting the θ angle to maintain α2 ≥ 30° until the upper edge plate has solidified. Figure 6 Adjust the θ angle back to 0, the mold shell returns to a vertical position and is completely lowered into the cold chamber, and the casting is completely solidified. Figure 7 This process yields a single-crystal guide casting with crystal orientation parallel to the blade's main axis, and free of impurities and with a porous rim.

[0058] In this embodiment, during the solidification process of the blade casting (including upper and lower edge plates and blade body) Figures 3 to 6 Although the macroscopic solidification direction of the molten metal is no longer parallel to the main axis of the blade, the crystal orientation of the grown single crystal remains unchanged and is always consistent with the crystal orientation of the transition section. That is, the axis of the single crystal blade is parallel to the

[001] crystal orientation of the single crystal. During the single crystal solidification process of the blade, the single crystal growth starts from the oblique lower corner of the blade's lower edge plate. A portion continues to grow along the lower edge plate and sequentially grows into each blade body, while another portion grows into the upper edge plate along the crystal guide strip. The solidification process of the two edge plates and each blade body is always obliquely upward. Because it is constantly fed by liquid from the oblique upper side, no visible porosity is produced on the surface or inside of the two edge plates and each blade body.

[0059] It should be explained that the control of α1 and finally α2 throughout the process is achieved through the adjustment of θ, which is automatically controlled by computer programming. The relationship between the position of the solidification interface within the casting and the shell-lowering distance is determined beforehand based on computer simulations and experimental measurements. The required inclination angles α1 and α2 of the tangent to the flange at that time are calculated based on the casting shape and incorporated into the control program. During production, as the shell-lowering distance changes, the tilt angle θ of the base plate is automatically adjusted to obtain the corresponding angles α1 and α2. After the entire blade has solidified, the tilted quench plate tilts back to its original position, facilitating the removal of the mold shell for subsequent shell cleaning and other operations.

[0060] Unless otherwise stated, if any of the technical solutions disclosed in this invention specify a numerical range, then the disclosed numerical range is a preferred numerical range. Anyone skilled in the art should understand that the preferred numerical range is merely one among many feasible numerical values ​​that has a more obvious or representative technical effect. Because there are many numerical values, it is impossible to list them all. Therefore, this invention discloses only some numerical values ​​to illustrate the technical solutions of this invention. Furthermore, the numerical values ​​listed above should not constitute a limitation on the scope of protection of this invention.

[0061] Furthermore, if the present invention discloses or relates to mutually fixedly connected components or structural parts, then unless otherwise stated, a fixed connection can be understood as: a detachable fixed connection (e.g., using bolts or screws), or a non-detachable fixed connection (e.g., riveting, welding). Of course, mutually fixed connections can also be replaced by an integral structure (e.g., manufactured using a casting process) (except where it is obviously impossible to use an integral molding process).

[0062] Furthermore, unless otherwise stated, the terms used to indicate positional relationships or shapes in any of the technical solutions disclosed in this invention include states or shapes that are similar to, analogous to, or close to those states or shapes. Any component provided by this invention can be assembled from multiple individual components or can be a single component manufactured using a one-piece molding process.

[0063] The above embodiments are merely illustrative examples to clearly illustrate the present invention and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all embodiments here. However, obvious variations or modifications derived therefrom are still within the scope of protection of this invention.

Claims

1. A method for preparing multi-unit single-crystal blades, characterized in that, include: Blade prototype manufacturing stage: Multiple blade wax models are positioned and assembled one by one; During the assembly of blade wax models, the thickness of the shims in the splicing seams is adjusted to ensure that the spacing between adjacent blade wax models meets the design requirements. Multiple blade wax models are then connected as one unit by injecting wax liquid into the splicing seams. Afterward, the shims are removed, and the space left by the shims is filled with wax liquid. The above-mentioned multi-blade wax mold is used to make a mold shell, the mold shell is poured to obtain a casting, the dimensions of the casting are checked, and the actual spacing between adjacent blades is determined. Blade mass production stage: The thickness of the shim is adjusted based on the difference between the actual blade spacing and the design spacing. The adjusted shim thickness is equal to the difference between the actual blade spacing and the design spacing. Then, multiple blade wax models are positioned and assembled one by one. Adjusted shims are placed in the splicing seams of adjacent blade wax models. The splicing seams are filled with wax liquid. After the wax liquid solidifies, the shims are removed and the space left by the shims is filled with wax liquid. Finally, the multi-section single crystal blade is prepared using the multi-section blade wax models with adjusted spacing. The quench plate of the directional solidification furnace is designed to be tiltable. When the assembled multi-blade wax mold is combined with the spiral crystal selector wax mold, the spiral crystal selector wax mold is connected to the corner of the lower edge plate of the blade wax mold, and the axes of the two are kept parallel. The corresponding corners of the upper and lower edge plates of the blade wax mold are connected by crystal guide strips. During directional solidification, the crystal-starting end of the spiral crystal selector is vertically installed on the quench plate. As the quench plate descends horizontally in the cold chamber of the directional solidification furnace, single crystals parallel to the blade axis grow vertically in the spiral crystal selector. When the single crystal grows to the transition section connecting the spiral crystal selector and the lower edge plate of the blade, the quench plate and the blade mold shell are slowly adjusted to tilt and then descended at the designed speed to ensure the sequential solidification of the blade edge plates and avoid the generation of impurities at the edge plate corners and the porosity of the edge plate surface.

2. The method for preparing multi-unit single-crystal blades according to claim 1, characterized in that: The tilt angle θ of the quench plate is dynamically adjusted according to the positional changes of the solidification interface. The specific adjustment process is as follows: During the process of the solidification interface moving from the transition section connecting the spiral crystal selector and the lower edge plate of the blade to the lower end of the upper edge plate of the blade, the tilt angle θ of the quench plate is continuously adjusted to keep the tilt angle α1 of the tangent of the lower edge plate of the blade ≥ 30°, while ensuring that the tilt angle β of the crystal guide strip below the blade edge plate is ≥ 30°. During the process of the solidification interface moving from the lower end of the upper edge plate of the blade to the upper end of the lower edge plate of the blade, the tilt angle θ of the quench plate is continuously adjusted to keep the tilt angle α1 of the tangent of the lower edge plate of the blade ≥ 30°, while ensuring that the tilt angle α2 of the tangent of the upper edge plate of the blade ≥ 30°. During the solidification process from the upper edge of the blade's lower edge plate to the completion of the entire blade's solidification, the tilt angle θ of the quench plate is continuously adjusted to maintain the tilt angle α2 of the upper edge plate's tangent at ≥30°.

3. The method for preparing multi-unit single-crystal blades according to claim 2, characterized in that: The cooling plate is a copper water-cooled plate.

4. The method for preparing multi-unit single-crystal blades according to claim 3, characterized in that: The directional solidification furnace is a vacuum furnace.

5. The method for preparing multi-unit single-crystal blades according to any one of claims 1-4, characterized in that: When assembling the blade wax model, first place two individual blade wax models side by side on the base of the positioning fixture, and place a shim between the joint of the two blade wax models. Use the flat positioning blocks on the base to keep the upper and lower ends of the two blade wax models aligned. Then, place the front ends of the two blade wax models against the corresponding arc-shaped positioning blocks on the base to keep the front and rear ends of the blade wax models aligned. Then, use a clamp or manually pinch the two blade wax models to clamp the shim in the middle. Next, fill the joint with wax liquid to connect the two blade wax models into one. Then, move one blade wax model to the position and repeat the above steps to assemble multiple single blade wax models into the required multi-section blade wax model.

6. The method for preparing multi-unit single-crystal blades according to claim 5, characterized in that: A gasket fixing support is provided on the base. The gasket is clamped by a clamping plate. The gasket fixing support is provided with a channel for the clamping plate to pass through. The tail end of the clamping plate is also provided with a limiting block to limit the insertion depth of the clamping plate.

7. A multi-stage single-crystal blade, characterized in that: The multi-unit single-crystal blade was prepared using the method described in any one of claims 1-6.

Images