Method for removing ceramic shell of high-temperature alloy directional blade

Abstract

The invention discloses a method for removing a ceramic shell of a high-temperature alloy directional blade, which belongs to the technical field of high-temperature alloy investment casting, and realizes the self-boosting of a shelling system by utilizing low-boiling-point substances such as ethanol in a shelling agent through the cooperative action of a shelling device, a shelling agent, a temperature and pressure control device and a process, so that the shelling effect of the high-temperature alloy directional blade is improved. The problem that pressure needs to be pre-filled or the pressure in a reaction system is low in an existing shelling process is solved, so that the shelling process is simplified, and the cost is reduced; through the shelling method that the shelling device is matched with the shelling agent, the exchange rate of the shelling agent and the surface of the ceramic shell is increased by adopting the physical technology of vibration stirring, further reaction is promoted, the shelling efficiency of the directional blades is improved, and batch treatment of ceramic shell removal is achieved.

Description

Technical Field

[0001] The present invention belongs to the technical field of investment casting of superalloys, and particularly relates to a method for removing ceramic mold shells of superalloy directional blades. Background Art

[0002] With the continuous development of aero-engine and gas turbine technologies, the performance requirements for blades are gradually increasing. Superalloy directional blades (i.e., the general term for superalloy single crystal blades and columnar crystal blades) have become the first choice for hot-end components of engines. Aero-engine superalloy single crystal turbine blades are prepared by investment precision casting. The mold shells used for casting are mainly alumina-based ceramic mold shells prepared with alumina as the matrix, silica sol as the binder, and an Al-Si-based mineralizer. Alumina-based ceramic mold shells have good chemical stability, low thermal expansion coefficient, high temperature resistance, good high-temperature creep resistance, and good chemical compatibility with active metal elements. However, their disadvantage is that they have high strength after casting and are difficult to remove. Therefore, it is necessary to research and explore the mold shell removal process to achieve high-quality development in China's aero-engine industry.

[0003] Traditional ceramic mold shells are removed by physical methods such as mechanical knocking and sandblasting. However, since this process will introduce plastic deformation on the surface of the turbine blade, the stored energy of this deformation will act as the driving force for recrystallization on the blade surface during subsequent heat treatment processes, thus affecting the service performance of the turbine blade. Therefore, nowadays, chemical corrosion methods are mostly used to remove the mold shells for casting aero-engine superalloy turbine blades.

[0004] A Chinese invention patent with the publication number CN104325120A relates to a method for removing a single crystal blade ceramic mold shell. This patent selects a potassium hydroxide aqueous solution with a weight concentration of 30 - 60% as the mold shell remover, heating temperature: 400°C - 600°C; pressure: 0.5MPAa - 2MPa; mold shell removal time: 6h - 24h. This method has too high requirements for temperature and low pressure in the reaction kettle, resulting in slow mold shell removal efficiency and being difficult to apply to the mold shell removal treatment of a large number of single crystal blades. To solve the pressure problem during mold shell removal, a Chinese invention patent with the publication number CN111992695B relates to a method for removing a ceramic mold shell of a single crystal superalloy blade. This patent selects a sodium hydroxide aqueous solution with a weight concentration of 30 - 65% as the mold shell remover, and the mold shell removal heating temperature cycles between low and high temperatures. The low temperature range: 100 - 140°C, heat preservation time 1 - 30min, the high temperature range 200 - 370°C, high temperature heat preservation time 5 - 60min, mold shell removal pressurization pressure: 0.2 - 1.5MPa, mold shell removal time: 3 - 48h. This method can effectively remove the alumina-based ceramic mold shell, but this patent uses a complex heating and cooling system and requires external pre-charged pressure. The mold shell removal process is complex and costly, and it is difficult to apply to the mold shell removal treatment of a large number of single crystal superalloy blades. Summary of the Invention

[0005] The present invention provides a method for removing ceramic mold shells from directionally solidified blades of superalloys, which is used to solve the technical problems raised in the above-mentioned background art.

[0006] To achieve the above object, the technical solution adopted by the present invention is as follows:

[0007] A method for removing ceramic mold shells from directionally solidified blades of superalloys, comprising the following steps:

[0008] S1. Load the directionally solidified blade to be processed into the reaction kettle of the shell removal device;

[0009] S2. Prepare a shell removal agent according to the component ratio of 30-60% strong alkali aqueous solution, 0.5-10% surfactant, 0.5-5% deoxidizer, and 0.5-5% catalyst. After preparing the shell removal agent at normal temperature according to the ratio, add it to the reaction kettle of the shell removal device;

[0010] S3. Start the shell removal device to perform shell removal treatment on the directionally solidified blade until the shell removal is completed;

[0011] S4. Heat up the reaction kettle through the shell removal device. When the temperature rises to 80-150 °C, exhaust the gas. After exhausting the gas in the reaction kettle, stop and close the exhaust, and continue to heat up to 250-350 °C, keep warm for 1-10 h, and the holding pressure is 2-10 MPa;

[0012] S5. Stop heating and cool down the reaction kettle through the shell removal device;

[0013] S6. Take out the directionally solidified blade from the shell removal device and wash it multiple times to remove the residual shell removal agent on the directionally solidified blade;

[0014] S7. Put the washed directionally solidified blade into a drying device for drying treatment.

[0015] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0016] Through the combined action of devices and processes such as the shell removal device, shell removal agent, temperature and pressure control, etc., the present invention utilizes low-boiling substances such as ethanol in the shell removal agent to achieve self-boosting pressure in the shell removal system, solves the problems of pre-charging pressure required in the existing shell removal process or low pressure in the reaction system, thereby simplifies the shell removal process and reduces costs; through the shell removal method of combining the shell removal device and the shell removal agent, the physical technology of vibration stirring is adopted to improve the exchange rate between the shell removal agent and the surface of the ceramic mold shell, promote the further progress of the reaction, improve the shell removal efficiency of the directionally solidified blade, and realize batch processing of ceramic mold shell removal.

[0017] As a further improvement of the above solution, the active agent is a compound containing organic substances such as acetone, ethanol, propanol, and isopropanol.

[0018] The technical effect of the above improvement is that through the setting of the compound of organic substances such as acetone, ethanol, propanol, and isopropanol in the active agent, the surface tension of the shelling agent of the present invention can be reduced, so that the shelling agent can penetrate more effectively into the mold shell of the directional vane. In addition, low-boiling substances such as ethanol can realize self-boosting pressure in the reaction kettle, increasing the driving force for the strong alkaline aqueous solution to contact the inside of the mold shell, and further improving the removal efficiency of the ceramic mold shell of the directional vane of the present invention.

[0019] As a further improvement of the above solution, the deoxidizer contains an oxygenophilic metal.

[0020] The technical effect of the above improvement is that through the setting of the oxygenophilic metal, the deoxidizer of the present invention can provide cathodic protection for the directional vane, avoiding chemical corrosion of the vane surface by the alkaline shelling agent during the long-term shelling reaction, and further improving the effect of removing the ceramic mold shell of the directional vane of the present invention.

[0021] As a further improvement of the above solution, the loading volume ratio of the shelling agent in the reaction kettle is 60%-90%.

[0022] The technical effect of the above improvement is that through the setting of the loading volume ratio, the present invention can quantify the shelling agent loaded into the 4, avoiding waste caused by too much shelling agent and poor listening effect caused by too little, and further improving the shelling efficiency.

[0023] As a further improvement of the above solution, the shelling device includes a support frame, the support frame is equipped with a heating mounting table, a reaction kettle is installed in the heating mounting table, the reaction kettle includes a kettle body, a kettle cover is installed at the upper end of the kettle body, a tooling grid adapted to the inner cavity of the kettle body for clamping the directional vane is detachably installed in the kettle body, a magnetic stirrer is rotatably installed at the center position of the kettle cover, an exhaust device is arranged at the upper end of the kettle cover, a temperature measuring thermocouple penetrates through the kettle cover, the magnetic stirrer includes a rotatably installed rotating shaft and stirring blades arranged at the lower part of the outer wall of the rotating shaft, and a circulating water cooling pipe is spirally wound around the outside of the rotating shaft at the lower end of the reaction kettle.

[0024] The technical effect of the above improvement is that through the setting of structures such as the heating mounting table, the reaction kettle, and the magnetic stirrer, the shelling device does not require mechanical vibration, hydraulic force, sandblasting and other methods for shelling and core removal, avoiding damage to the vane. Through the agitation of the magnetic stirrer in cooperation with the shelling agent, the efficiency of shelling and core removal of the directional vane is further improved.

[0025] As a further improvement of the above solution, a driving part is provided on one side of the upper end surface of the support frame, and the output end of the driving part is transmission-connected to the rotating shaft through a magnetic coupler.

[0026] The technical effect of the above improvement is that, through the arrangement of the magnetic coupler and the driving part, the shelling device can further conveniently control the rotation of the magnetic stirrer.

[0027] As a further improvement of the above solution, cooling water pipes are provided on both sides of the magnetic coupler.

[0028] The technical effect of the above improvement is: by setting the cooling water pipe, the shelling device can cool the magnetic coupler through the cooling water pipe.

[0029] As a further improvement of the above solution, a rotating bracket is provided on one side of the support frame, and a lift is installed on the upper end of the rotating bracket.

[0030] The technical effect of the above improvement is: through the setting of the rotating bracket and the elevator, the shelling device is convenient for installing and removing the kettle cover and the tooling grid, which further facilitates the operation of the shelling device.

[0031] As a further improvement of the above scheme, the tooling grid includes a grid, lifting ears are arranged at intervals at the top edge of the grid, an inner barrel is arranged at the center position of the grid, the inner barrel is cylindrical, the chamber between the inner wall of the grid and the outer wall of the inner barrel is separated by partitions arranged at intervals, grid boxes are installed in a circular array in the chamber separated by the partitions in the grid, the outer wall shape of the grid is adapted to the inner cavity shape of the kettle body, the inner diameter size of the inner barrel side wall is adapted to the magnetic stirrer, and through holes are arranged at intervals on the outer walls of the grid, the partitions and the inner barrel.

[0032] The technical effect of the above improvement is: through the arrangement of structures such as grids, partitions, and grid boxes, the tooling grid in the reactor can fix the directional blades in the reactor in a layered and spaced manner for shelling, thereby avoiding collision between the blades and the reactor and between each other, preventing secondary bonding, and making the installation convenient, time-saving, and labor-saving. The structure is simple and the cost is low, and it can be reused, which further improves the removal efficiency of the directional blade ceramic shell.

[0033] As a further improvement of the above scheme, the net box includes a box body, one end of which is rotatably mounted with a movable cover via a hinge, a spring is mounted at the lower end of the movable cover and at the bottom of the end of the box body away from the movable cover, and the outer walls of the box body and the movable cover are grid-shaped.

[0034] The technical effect of the above improvement is: through the arrangement of the box body, the spring and the movable cover, the net box can be further conveniently and stably loaded into the directional blades and the net box can be neatly loaded into the net frame, which is convenient for operation. Brief Description of the Drawings

[0035] Figure 1 This is the front view structural schematic diagram of the present invention.

[0036] Figure 2 This is the front view structural schematic diagram of the reactor of the present invention.

[0037] Figure 3 This is the front view sectional structural schematic of the reactor of the present invention Figure 1 .

[0038] Figure 4 This is the front view sectional structural schematic of the reactor of the present invention Figure 2 .

[0039] Figure 5 This is the partial structural schematic diagram of the reactor of the present invention.

[0040] Figure 6 This is the three-dimensional structural schematic diagram of the tooling grid of the present invention.

[0041] Figure 7 This is the three-dimensional sectional structural schematic diagram of the grid of the present invention.

[0042] Figure 8 This is the top view structural schematic diagram of the tooling grid of the present invention.

[0043] Figure 9 This is the three-dimensional structural schematic diagram of the mesh box of the present invention.

[0044] In the figure: 1, support frame; 2, rotating bracket; 3, heating installation platform; 4, reactor; 41, kettle body; 42, kettle cover; 43, circulating water cooling pipe; 44, temperature measuring thermocouple; 5, magnetic coupler; 6, driving part; 7, elevator; 8, cooling water pipe; 9, magnetic stirrer; 91, stirring blade; 92, rotating shaft; 10, tooling grid; 101, grid; 102, partition board; 103, lifting ear; 104, inner barrel; 11, mesh box; 111, box body; 112, spring; 113, movable cover. Detailed Embodiments

[0045] In order to enable those skilled in the art to better understand the technical solution, the present invention will be described in detail below in conjunction with embodiments. The description in this part is only exemplary and explanatory, and should not have any restrictive effect on the protection scope of the present invention.

[0046] Embodiment 1:

[0047] The specific solution of this embodiment is as follows: A method for removing the ceramic mold of a superalloy directional blade, including the following steps:

[0048] S1. Load the to-be-processed directional vane into the reaction kettle 4 of the shelling device;

[0049] S2. Prepare the shelling agent according to the component ratio of 30 - 60% strong alkali aqueous solution, 0.5 - 10% surfactant, 0.5 - 5% deoxidizer, and 0.5 - 5% catalyst. The strong alkali aqueous solution is NaOH or KOH solution, and the catalyst is a neutral salt such as NaCl or KCl. After preparing the shelling agent at room temperature according to the ratio, add it into the reaction kettle 4 of the shelling device, or directly prepare the shelling agent in the reaction kettle 4;

[0050] S3. Start the shelling device to perform shelling treatment on the directional vane until the shelling is completed;

[0051] S4. Heat up the inside of the reaction kettle 4 through the shelling device. When the temperature rises to 80 - 150 °C, exhaust the gas. After exhausting the gas in the reaction kettle 4, stop and close the exhaust, and continue to heat up to 250 - 350 °C, and keep the temperature for 1 - 10 h. The holding pressure is 2 - 10 MPa; the specific parameters also need to be determined according to the number of directional vanes and the residual ratio of the shell;

[0052] S5. Stop heating, and cool down the inside of the reaction kettle 4 through the shelling device until the temperature drops below 100 °C;

[0053] S6. Take out the directional vane from the shelling device, put the directional vane into the cleaning device, and perform multiple cleanings on the directional vane to remove the residual shelling agent on the directional vane;

[0054] S7. Put the cleaned directional vane into the drying device for drying treatment. The drying temperature ≤ 100 °C, and the drying time is 0.5 - 3 h.

[0055] Example 2:

[0056] As a preferred embodiment of the above embodiments, the active agent is a compound containing organic substances such as acetone, ethanol, propanol, and isopropanol. By setting the compound of acetone, ethanol, propanol, and isopropanol organic substances in the active agent, the surface tension of the shelling agent of the present invention can be reduced, so that the shelling agent can penetrate more effectively into the mold shell of the directional vane. In addition, low-boiling-point substances such as ethanol can achieve self-boosting pressure in the reaction kettle 4, increasing the driving force for the strong alkaline aqueous solution to contact the inside of the mold shell, and further improving the removal efficiency of the ceramic mold shell of the directional vane of the present invention. The deoxidizer contains an oxygenophilic metal, and the oxygenophilic metal is selected from one or more of sponge titanium or oxygenophilic metals such as Ni, Y, Hf, Zr, and Al in this embodiment. By setting the oxygenophilic metal, the deoxidizer of the present invention can provide cathodic protection for the directional vane, avoiding chemical corrosion of the vane surface by the alkaline shelling agent during the long-term shelling reaction, and further improving the removal effect of the ceramic mold shell of the directional vane of the present invention. The loading volume ratio of the shelling agent in the reaction kettle 4 is 60%-90%. By setting the loading volume ratio, the present invention can quantify the shelling agent loaded into the reaction kettle 4, avoiding waste caused by excessive shelling agent and poor shelling effect caused by too little, and further improving the shelling efficiency.

[0057] Example 3:

[0058] As Figures 1-5As shown, as a preferred embodiment of the above embodiment, the shelling device includes a support frame 1, a heating mounting platform 3 is installed in the support frame 1, a reactor 4 is installed in the heating mounting platform 3, the reactor 4 includes a reactor body 41, a reactor cover 42 is installed on the upper end of the reactor body 41, a tooling grid 10 adapted to the inner cavity of the reactor body 41 for clamping directional blades is detachably installed in the reactor body 41, a magnetic stirrer 9 is rotatably installed at the center position of the reactor cover 42, an exhaust device is arranged on the upper end of the reactor cover 42, the exhaust device is an exhaust pipe connected with a switch and a pressure gauge, a temperature measuring thermocouple 44 is penetrated on the reactor cover 42, the magnetic stirrer 9 includes a rotatably mounted rotating shaft 92 and a stirring blade 91 arranged on the lower part of the outer wall of the rotating shaft 92, and a circulating water cooling pipe 43 is spirally arranged on the outer side of the rotating shaft 92 at the lower end of the reactor 4. By setting the heating installation platform 3, the reactor 4, the magnetic stirrer 9 and other structures, the shelling device does not need mechanical vibration, hydraulic and sand blowing methods to shell and core, thus avoiding damage to the blades. The stirring of the magnetic stirrer 9 and the shelling agent further improve the efficiency of directional blade shelling and core removal. A driving part 6 is arranged on one side of the upper end surface of the support frame 1. The driving part 6 is a motor in this embodiment, and the output end of the driving part 6 is connected to the rotating shaft 92 through a magnetic coupler 5. Through the arrangement of the magnetic coupler 5 and the driving part 6, the shelling device can further conveniently control the rotation of the magnetic stirrer 9. Cooling water pipes 8 are arranged on both sides of the magnetic coupler 5. Through the arrangement of the cooling water pipe 8, the shelling device can cool the magnetic coupler 5 through the cooling water pipe 8. A rotating bracket 2 is arranged on one side of the support frame 1, and a lift 7 is installed on the upper end of the rotating bracket 2. By setting the rotating bracket 2 and the elevator 7, the shelling device can be conveniently installed and removed from the kettle cover 42 and the tooling grid frame 10, which further facilitates the operation of the shelling device.

[0059] Embodiment 4:

[0060] like Figures 6-9As shown in the figure, as a preferred embodiment of the above embodiment, the tooling grid 10 includes a grid 101. At the top edge of the grid 101, lifting lugs 103 are arranged at intervals. At the central position inside the grid 101, an inner barrel 104 is arranged. The inner barrel 104 is cylindrical. The chamber between the inner wall of the grid 101 and the outer wall of the inner barrel 104 is separated by partition plates 102 arranged at intervals. In the chambers separated by the partition plates 102 inside the grid 101, mesh boxes 11 are installed in an annular array. The outer wall shape of the grid 101 is adapted to the inner cavity shape of the kettle body 41. The inner diameter size of the side wall of the inner barrel 104 is adapted to the magnetic stirrer 9. Through holes are arranged at intervals through the outer walls of the grid 101, the partition plates 102, and the inner barrel 104. Through the settings of structures such as the grid 101, the partition plates 102, and the mesh boxes 11, the tooling grid 10 in the reaction kettle 4 can perform shell removal treatment on the fixed orientation blades in the reaction kettle 4 in a layered and spaced manner, avoiding collisions between the blades and the reaction kettle 4 and between the blades themselves, preventing secondary adhesion, being convenient, time-saving, and labor-saving in installation, having a simple structure and low cost, being reusable, and further improving the removal efficiency of the ceramic shell of the orientation blades. The mesh box 11 includes a box body 111. One end of the box body 111 is rotatably installed with a movable cover 113 through a hinge. Springs 112 are installed at the lower end of the movable cover 113 and at the bottom of the end of the box body 111 away from the movable cover 113. The outer walls of the box body 111 and the movable cover 113 are grid-shaped. Through the settings of the box body 111, the springs 112, and the movable cover 113, the mesh box 11 can further facilitate and stably load the orientation blades and facilitate the neat loading of the mesh box 11 into the grid 101, which is convenient for operation. In this embodiment, the area between the bottom of the kettle body 41 of the reaction kettle 4 and the lowermost partition plate 102 is used to receive and store the slag of the ceramic shell and the core that fall off the blades, which can prevent the shell from remaining in the reaction kettle 4 and increasing the difficulty of later cleaning.

[0061] Specific working principle:

[0062] Use the elevator 7 to place and install the grid frame 101 in the inner cavity of the reaction kettle 4 through the lifting lug 103. First, take out the mesh box 11, open the movable cover 113, put the orientation vane into the box body 111 and then close the movable cover 113. The orientation vane is pressed and fixed by the springs 112 at the upper and lower ends in the mesh box 11. Subsequently, put the mesh box 11 on the partition plate 102 in the grid frame 101, and repeat the above process until the upper end face of the partition plate 102 is neatly filled with the mesh boxes 11, and then cover another layer of partition plate 102. Repeat this way to install and cover layer by layer of partition plates 102 in the grid frame 101 until the grid frame 101 is filled; finally, close the reaction kettle 4, and the stirrer of the reaction kettle 4 penetrates into the inner barrel 104, and start the reaction kettle 4 to carry out the shell removal treatment on the orientation vanes in the mesh box 11; after the reaction process is completed, open the reaction kettle 4, use the elevator 7 to take out the grid frame 101 from the inner cavity of the reaction kettle 4 through the lifting lug 103, and then take out the orientation vanes from the mesh boxes 11 in the grid frame 101, and clean the tooling grid frame 10 as appropriate.

[0063] Example 5:

[0064] In a specific process for removing the ceramic shell of a superalloy orientation vane, the following steps are included:

[0065] , when the shell removal and core removal reaction in the reaction kettle 4 is completed, turn the rotating bracket 2 to move the elevator 7 to directly above the reaction kettle 4, open the kettle cover 42, raise and remove the kettle cover 42 through the elevator 7, and finally take out the superalloy orientation vane after shell removal and core removal from the kettle body 41

[0066] S1. Open the kettle cover 42, and place the superalloy orientation vane to be subjected to shell removal treatment into the kettle body 41 through the tooling grid frame 10 and fixedly install it;

[0067] S2. Prepare a shell removal agent according to the composition ratio of 60% strong alkali aqueous solution, 10% surfactant, 5% deoxidizer, and 5% catalyst. After preparing the shell removal agent at normal temperature according to the ratio, add it into the kettle body 41, and then seal and close the kettle cover 42;

[0068] S3. Start the driving part 6, drive the magnetic stirrer 9 in the reaction kettle 4 to rotate through the magnetic coupling 5, cooperate with the shell removal agent in the kettle body 41 to carry out the shell removal treatment on the orientation vane, open the cooling water pipe 8, and cool and control the temperature of the magnetic coupling 5 until the shell removal ends and stops;

[0069] S4. Start the heating installation platform 3 to heat the reaction kettle 4, and the temperature in the kettle body 41 rises in cooperation with the temperature measured by the temperature measuring thermocouple 44. When it rises to 120 °C, open the exhaust device to exhaust, stop and close the exhaust after exhausting the gas in the reaction kettle 4, continue to heat up to 320 °C, keep warm for 10 h, and the holding pressure is 10 MPa;

[0070] S5. Stop heating the reaction kettle 4 by the heating installation table 3, start the water valve of the circulating water cooling pipe 43 to cool down the inside of the kettle body 41, and cooperate with the detection of the temperature measuring thermocouple 44 to cool down to below 100 °C;

[0071] S6. Rotate the rotating bracket 2 to move the elevator 7 directly above the reaction kettle 4, open the kettle lid 42, raise and remove the kettle lid 42 through the elevator 7, and finally take out the shelled superalloy directional vane from the tooling grid 10 of the kettle body 41, put the directional vane into the flushing device, and wash the directional vane multiple times to remove the residual shelling agent on the directional vane;

[0072] S7. Put the washed directional vane into the drying device for drying treatment, with the drying temperature ≤ 100 °C and the drying time of 3 h.

[0073] Through the combined action of devices and processes such as the shelling device, shelling agent, temperature and pressure control, etc., the present invention utilizes low-boiling substances such as ethanol in the shelling agent to achieve self-pressure boosting of the shelling system, solves the problems of pre-charging pressure required in the existing shelling process or low pressure in the reaction system, thereby simplifies the shelling process and reduces costs; through the shelling method of combining the shelling device with the shelling agent, the physical technology of vibration stirring is adopted to improve the exchange rate between the shelling agent and the surface of the ceramic mold shell, promote the further progress of the reaction, improve the shelling efficiency of the directional vane, and realize the batch treatment of removing the ceramic mold shell.

[0074] It should be noted that in this article, the terms "including", "comprising" or any other variant thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements not only includes those elements, but also includes other elements not expressly listed, or also includes elements inherent to such process, method, article or device. Specific examples are used in this article to elaborate on the principle and implementation manner of the technical solution of the present invention. The description of the above examples is only used to help understand the method and its core idea of the present invention. The above is only the preferred implementation manner of the present invention. It should be pointed out that due to the limited nature of written expression and objectively existing infinite specific structures, for those of ordinary skill in the art in this technical field, without departing from the principle of the present invention, several improvements, retouches or changes can be made, or the above technical features can be combined in an appropriate manner; these improvements, retouches, changes or combinations, or directly applying the concept and technical solution of the invention to other occasions without improvement, should all be regarded as the protection scope of the present invention.

Claims

1. A method for removing ceramic mold shells of superalloy directional blades, characterized in that, The following steps are involved: S1, placing the directional leaves to be treated into the reactor (4) of the shelling device; S2, preparing a dehulling agent according to the composition ratio of 30-60% strong alkali aqueous solution, 0.5-10% active agent, 0.5-5% deoxidizing agent and 0.5-5% catalyst, and adding the dehulling agent into the reaction kettle (4) of the dehulling device after the dehulling agent is prepared in proportion at room temperature; S3, starting the shelling device to shell the directional blades until the shelling is completed; S4, heating the reactor (4) by means of a shelling device, exhausting the gas when the temperature reaches 80-150°C, stopping and closing the exhaust after the gas in the reactor (4) is exhausted, and continuing to heat the reactor to 250-350°C, keeping the temperature for 1-10h, and keeping the temperature at a pressure of 2-10MPa; S5, stopping heating and cooling the reaction kettle (4) by means of a shelling device; S6, taking out the directional blades from the shelling device, washing the directional blades multiple times, and removing the shelling agent remaining on the directional blades; S7, placing the cleaned directional blades into a drying device for drying.

2. A method for removing a ceramic mold shell of a superalloy directional vane according to claim 1, characterized in that, The active agent is a compound containing acetone, ethanol, propanol and isopropanol organic matter.

3. A method for removing a ceramic mold shell of a superalloy directional vane according to claim 1, characterized in that, The oxygen scavenger contains an oxophilic metal.

4. A method for removing a ceramic mold shell of a superalloy directional vane according to claim 1, characterized in that, The loading volume ratio of the dehulling agent in the reaction kettle (4) is 60%-90%.

5. A method for removing a ceramic mold shell of a superalloy directional blade according to claim 1, characterized in that, The shelling device comprises a support frame (1), the support frame (1) is equipped with a heating installation platform (3), a reaction kettle (4) is installed in the heating installation platform (3), the reaction kettle (4) comprises a kettle body (41), a kettle cover (42) is installed at the upper end of the kettle body (41), a tooling grid frame (10) adapted to the inner cavity of the kettle body (41) for clamping directional blades is detachably installed in the kettle body (41), a magnetic stirrer (9) is rotatably installed at the center position of the kettle cover (42), an exhaust device is arranged at the upper end of the kettle cover (42), a temperature measuring electric thermocouple (44) is penetrated through the kettle cover (42), the magnetic stirrer (9) comprises a rotatably installed rotating shaft (92) and a stirring blade (91) arranged at the lower part of the outer wall of the rotating shaft (92), and a circulating water cooling pipe (43) is spirally arranged on the outer side of the rotating shaft (92) at the lower end of the reaction kettle (4).

6. A method for removing a ceramic shell of a superalloy directional vane according to claim 5, characterized in that, A driving part (6) is provided on one side of the upper end surface of the support frame (1), and an output end of the driving part (6) is transmission-connected to a rotating shaft (92) via a magnetic coupler (5).

7. A method for removing a ceramic mold shell of a superalloy directional vane according to claim 5, characterized in that, Cooling water pipes (8) are provided on both sides of the magnetic coupler (5).

8. A method for removing a ceramic mold shell of a superalloy directional blade according to claim 5, characterized in that, A rotating bracket (2) is provided on one side of the support frame (1), and a lift (7) is installed on the upper end of the rotating bracket (2).

9. A method for removing a ceramic mold shell of a superalloy directional vane according to claim 5, characterized in that, The tooling grid frame (10) includes a grid frame (101). At the top edge of the grid frame (101), lifting lugs (103) are arranged at intervals. At the central position inside the grid frame (101), an inner barrel (104) is arranged. The inner barrel (104) is cylindrical. The chamber between the inner wall of the grid frame (101) and the outer wall of the inner barrel (104) is separated by partition plates (102) arranged at intervals. In the chambers separated by the partition plates (102) inside the grid frame (101), mesh boxes (11) are installed in an annular array. The outer wall shape of the grid frame (101) is adapted to the inner cavity shape of the kettle body (41). The inner diameter size of the side wall of the inner barrel (104) is adapted to the magnetic stirrer (9). Through holes are arranged at intervals through the outer walls of the grid frame (101), the partition plates (102), and the inner barrel (104).

10. A method for removing a ceramic mold shell of a superalloy directional blade according to claim 9, characterized in that, The mesh box (11) includes a box body (111). One end of the box body (111) is rotatably installed with a movable cover (113) through a hinge. Springs (112) are installed at the lower end of the movable cover (113) and the bottom of the end of the box body (111) away from the movable cover (113). The outer walls of the box body (111) and the movable cover (113) are grid-shaped meshes.

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