A cleaning method and apparatus for precision casting of titanium alloy shells.

Abstract

This invention belongs to the field of titanium alloy precision casting technology, and specifically relates to a cleaning method and apparatus for titanium alloy precision casting mold shells. The cleaning method includes: cooling an initial mold shell obtained through surface layer preparation, back layer preparation, dewaxing, and high-temperature calcination to room temperature; driving the initial mold shell to rotate, while simultaneously injecting a cleaning liquid into the inner cavity of the initial mold shell until the inner cavity is filled; the cleaning liquid includes anhydrous alcohol and ethyl silicate; stopping the initial mold shell after centrifugal rotation for a preset time, draining the cleaning liquid from the inner cavity of the initial mold shell, and placing the initial mold shell in a constant temperature environment to dry; and baking the dried initial mold shell to obtain a cleaned titanium alloy precision casting mold shell. The above method is simple to operate, has high repair efficiency, and produces ceramic mold shells with high surface smoothness, few ceramic residues, and few surface cracks, which can significantly improve the internal metallurgical quality of the final titanium alloy casting product.

Description

Technical Field

[0001] This invention belongs to the field of titanium alloy precision casting technology, and specifically relates to a cleaning method and cleaning device for titanium alloy precision casting mold shells. Background Technology

[0002] The mold shells for precision casting of titanium alloys are typically made of double-layer ceramic materials. The outer layer is usually made of highly inert yttrium oxide ceramic, while the back layer is made of bauxite ceramic. Since the outer and back layers are made of different materials with significantly different coefficients of thermal expansion, uneven expansion during high-temperature sintering often leads to cracking of the inner wall of the mold shell, forming microcracks. Ceramic particles also detach from these cracks. If this mold shell is used directly for pouring molten titanium alloy, the molten metal will seep into the cracks and react with the bauxite, resulting in porosity and casting defects in the casting. Simultaneously, ceramic particles will mix into the molten metal, forming inclusions. These defects reduce the quality of the casting, increase the cost of subsequent defect cleaning, and in severe cases, lead to the casting being scrapped.

[0003] For the reasons mentioned above, the prepared shell first needs to undergo a cleaning step. However, titanium alloy shells typically have small openings and large internal cavities with complex shapes that are invisible to the naked eye. Traditional methods using blowers are insufficient to completely remove ceramic particles from the shell's internal cavity due to limitations in airflow reaching certain blind spots. Furthermore, surface cracks within the shell's internal cavity are a significant challenge in quality control, and currently, there is no way to repair surface cracks in the blind areas of the internal cavity. Summary of the Invention

[0004] The purpose of this invention is to provide a cleaning method and apparatus for titanium alloy precision casting shells, so as to at least partially solve some of the technical problems in the prior art.

[0005] The first aspect of this invention provides a method for cleaning a precision-cast titanium alloy mold shell, comprising the following steps:

[0006] The initial shell obtained through the steps of surface layer preparation, back layer preparation, dewaxing and high-temperature calcination is cooled to room temperature;

[0007] The initial shell is driven to rotate, and while rotating, a cleaning solution is injected into the inner cavity of the initial shell until the inner cavity is filled. The cleaning solution includes anhydrous alcohol and ethyl silicate. After centrifugal rotation for a preset time, the initial shell is stopped, the cleaning solution in the inner cavity of the initial shell is discharged, and the initial shell is placed in a constant temperature environment to dry.

[0008] The initial mold shell after drying is baked, and after baking, a cleaned titanium alloy precision casting mold shell is obtained.

[0009] The cleaning method for titanium alloy precision casting mold shells provided by this invention may also have the following additional technical features:

[0010] In one specific embodiment of the present invention, the anhydrous ethanol and ethyl silicate are mixed in a weight ratio of (2-4):1 and stirred for 10-20 minutes to fully fuse them to obtain the cleaning solution.

[0011] In one specific embodiment of the present invention, the initial shell is centrifuged at a speed of 10-20 r / min; after the cleaning solution is injected, the initial shell is stopped after centrifugation for 20-40 minutes.

[0012] In one specific embodiment of the present invention, the method further includes: sealing any excess dewaxing ports on the initial mold shell before driving the initial mold shell to rotate so that the inner cavity of the initial mold shell has only one injection opening; and opening the dewaxing ports after the initial mold shell stops rotating so that the cleaning fluid can be discharged naturally.

[0013] In one specific embodiment of the present invention, after the cleaning fluid is drained, the initial shell is placed in a constant temperature environment of 20-25°C and left to stand for at least 3 hours to dry the initial shell.

[0014] In one specific embodiment of the present invention, the baking treatment of the dried initial shell is specifically as follows: the initial shell is moved from the constant temperature environment into the baking oven for baking at a temperature of 300-600°C for 2-4 hours.

[0015] In one specific embodiment of the present invention, filling the inner cavity of the initial shell with cleaning fluid specifically involves: using a solution of 100-300 cm³. 3 The cleaning fluid is injected into the initial shell at a flow rate of / s until the inner cavity is filled with the cleaning fluid.

[0016] The present invention also provides a cleaning apparatus for a titanium alloy precision casting mold shell, used in the above-mentioned cleaning method for the titanium alloy precision casting mold shell, comprising:

[0017] A tray frame includes a support frame, a centrifugal disc, and a rotor motor. The centrifugal disc is rotatably mounted on the support frame. The rotor motor is mounted on the support frame, and its rotation shaft is connected to the centrifugal disc.

[0018] A mixing tank is provided with a mixing chamber and a mixing shaft inside, and a water pump is provided outside. The water pump has a conduit connecting its inlet and outlet ends, and the conduit at the inlet end is located in the mixing chamber.

[0019] In one specific embodiment of the present invention, a graphite plug is also included, which is used to seal the wax outlet of the initial shell.

[0020] The cleaning method for precision casting shells of titanium alloys provided by this invention utilizes a novel cleaning fluid and centrifugal force to flush the initial cavity of the shell. Due to the excellent filling and flowability of the cleaning fluid, it can reach the edges, corners, and dead zones of the shell, entraining ceramic particles in these areas. These particles are then completely expelled from the shell through the wax outlet. This method is not only simple to operate but also highly efficient. Furthermore, because the cleaning fluid penetrates into the microcracks on the surface of the shell cavity and remains even after discharge, it reacts with the oxide ceramics in the cracks during the shell baking process to form a hard filler. This filler can fill surface cracks no wider than 1 mm on the inner surface of the cavity, thus solving the current problem of unrepairable microcracks on the inner surface of the shell.

[0021] The cleaning device of the present invention has a simple structure, is easy to operate and has high repair efficiency. The prepared ceramic shell has a high surface smoothness, less ceramic residue and fewer surface cracks, which can significantly improve the metallurgical quality of the final titanium alloy casting product. Attached Figure Description

[0022] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0023] Figure 1 This is a schematic diagram of a cleaning device for a precision casting titanium alloy mold shell in a specific embodiment of the present invention.

[0024] Explanation of reference numerals in the attached figures:

[0025] 1-Support frame, 2-Centrifuge disc, 3-Rotor motor, 4-Agitator, 5-Water pump, 6-Conduit, 7-Initial shell. Detailed Implementation

[0026] Exemplary embodiments of the invention will now be described in more detail with reference to the accompanying drawings. While exemplary embodiments of the invention are shown in the drawings, it should be understood that the invention can be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided to enable a more thorough understanding of the invention and to fully convey the scope of the invention to those skilled in the art.

[0027] It should be understood that the terminology used herein is for the purpose of describing particular exemplary embodiments only and is not intended to be limiting. Unless the context clearly indicates otherwise, the singular forms “a,” “an,” and “described” as used herein may also include the plural forms. The terms “comprising,” “including,” “containing,” and “having” are inclusive and therefore indicate the presence of the stated features, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, steps, operations, elements, components, and / or combinations thereof. The method steps, processes, and operations described herein are not construed as requiring them to be performed in a particular order described or illustrated unless the order of performance is explicitly indicated. It should also be understood that additional or alternative steps may be used.

[0028] Although terms such as first, second, third, etc., may be used in this document to describe multiple elements, components, regions, layers, and / or segments, these elements, components, regions, layers, and / or segments should not be limited by these terms. These terms may be used only to distinguish one element, component, region, layer, or segment from another. Unless the context clearly indicates otherwise, terms such as "first," "second," and other numerical terms used herein do not imply order or sequence. Therefore, the first element, component, region, layer, or segment discussed below may be referred to as the second element, component, region, layer, or segment without departing from the teachings of the exemplary embodiments.

[0029] For ease of description, spatial relative terms may be used in the text to describe the relationship of one element or feature relative to another element or feature, as shown in the figure. These relative terms include, for example, "inside," "outside," "middle," "outer," "below," "below," "above," "over," etc. Such spatial relative terms are intended to include different orientations of the device in use or operation, other than those depicted in the figure. For example, if the device in the figure is flipped, an element described as "below other elements or features" or "below other elements or features" would subsequently be oriented as "above other elements or features" or "above other elements or features." Therefore, the example term "below" can include both upper and lower orientations. The device may be otherwise oriented (rotated 90 degrees or in other directions), and the spatial relative descriptors used in the text will be interpreted accordingly.

[0030] This invention provides a cleaning method for precision-cast titanium alloy shells, comprising the following steps:

[0031] The initial shell obtained through the steps of surface layer preparation, back layer preparation, dewaxing and high-temperature calcination is cooled to room temperature;

[0032] The initial shell is driven to rotate, and while rotating, a cleaning solution is injected into the inner cavity of the initial shell until the inner cavity is filled. The cleaning solution includes anhydrous alcohol and ethyl silicate. After centrifugal rotation for a preset time, the initial shell is stopped, the cleaning solution in the inner cavity of the initial shell is discharged, and the initial shell is placed in a constant temperature environment to dry.

[0033] The initial mold shell after drying is baked, and after baking, a cleaned titanium alloy precision casting mold shell is obtained.

[0034] The above-described cleaning method utilizes a novel cleaning solution, employing centrifugation to flush the inner cavity of the initial mold shell. Due to the cleaning solution's excellent filling and flowability, it reaches even the corners and hard-to-reach areas of the mold shell, entraining ceramic particles in these locations. These particles are then completely expelled from the mold shell through the wax outlet. This method is not only simple to operate but also highly efficient. Furthermore, because the cleaning solution penetrates into the micro-cracks on the inner surface of the mold shell and remains even after discharge, it reacts with the oxide ceramics in the cracks during the baking process, forming a hard filler. This filler can fill surface cracks no wider than 1 mm on the inner surface of the mold shell, thus solving the current problem of unrepairable micro-cracks on the inner surface of the mold shell.

[0035] In one specific embodiment of the present invention, the anhydrous ethanol and ethyl silicate are mixed in a weight ratio of (2-4):1 and stirred for 10-20 minutes to fully fuse them to obtain the cleaning solution.

[0036] In one specific embodiment of the present invention, the initial shell is centrifuged at a speed of 10-20 r / min; after the cleaning solution is injected, the initial shell is stopped after centrifugation for 20-40 minutes.

[0037] In one specific embodiment of the present invention, the method further includes: sealing any excess dewaxing ports on the initial mold shell before driving the initial mold shell to rotate so that the inner cavity of the initial mold shell has only one injection opening; and opening the dewaxing ports after the initial mold shell stops rotating so that the cleaning fluid can be discharged naturally.

[0038] In one specific embodiment of the present invention, after the cleaning fluid is drained, the initial shell is placed in a constant temperature environment of 20-25°C and left to stand for at least 3 hours to dry the initial shell.

[0039] In one specific embodiment of the present invention, the baking treatment of the dried initial shell is specifically as follows: the initial shell is moved from the constant temperature environment into the baking oven for baking at a temperature of 300-600°C for 2-4 hours.

[0040] In one specific embodiment of the present invention, filling the inner cavity of the initial shell with cleaning fluid specifically involves: using a solution of 100-300 cm³. 3 The cleaning fluid is injected into the initial shell at a flow rate of / s until the inner cavity is filled with the cleaning fluid.

[0041] like Figure 1 As shown, the present invention also discloses a cleaning device for a titanium alloy precision casting mold shell, which is used in the above-mentioned cleaning method for the titanium alloy precision casting mold shell, including:

[0042] The tray frame includes a support frame 1, a centrifugal disc 2, and a rotor motor 3. The centrifugal disc 2 is rotatably mounted on the support frame 1. The rotor motor 3 is mounted on the support frame 1, and its rotation shaft is connected to the centrifugal disc 2.

[0043] The mixing tank 4 is equipped with a mixing chamber and a mixing shaft inside, and a water pump 5 is also provided outside. The water pump has a conduit 6 connected to both the water inlet and the water outlet, and the conduit 6 at the water inlet is located in the mixing chamber.

[0044] Specifically, the centrifugal disc 2 is rotatably connected to the track on the support frame 1 via rollers, and rotates on the support frame 1 under the drive of the rotor motor 3, thereby driving the initial shell 7 fixed above the centrifugal disc 2 to rotate.

[0045] In one specific embodiment of the present invention, a graphite plug is also included, which is used to seal the wax outlet of the initial shell 7.

[0046] In the above structure, the centrifugal disc 2 is used to place and fix the initial shell 7, so that it can rotate the initial shell 7 when driven by the rotor motor 3, so that the cleaning fluid in the inner cavity of the initial shell 7 rotates centrifugally. The plug is suitable for sealing the excess wax outlet of the initial shell 7 so that the inner cavity of the initial shell 7 has only one inlet. The hose at the water inlet end of the water pump 5 is inserted into the stirring chamber, and the hose at the water outlet end is inserted into the inlet of the inner cavity of the initial shell 7, which is suitable for injecting cleaning fluid into its inner cavity when the initial shell 7 rotates until the inner cavity is filled with cleaning fluid.

[0047] The cleaning device described above has a simple structure, is easy to operate, and has high repair efficiency. The ceramic shell produced has a high surface finish, few ceramic residues, and few surface cracks, which can significantly improve the metallurgical quality of the final titanium alloy casting product.

[0048] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A cleaning method for a precision casting mold shell made of titanium alloy, characterized in that, Includes the following steps: The initial shell obtained through the steps of surface layer preparation, back layer preparation, dewaxing and high-temperature calcination is cooled to room temperature; The initial shell is driven to rotate, and while rotating, a cleaning solution is injected into the inner cavity of the initial shell until the inner cavity is filled. The cleaning solution includes anhydrous alcohol and ethyl silicate. After centrifugal rotation for a preset time, the initial shell is stopped, the cleaning solution in the inner cavity of the initial shell is discharged, and the initial shell is placed in a constant temperature environment to dry. The dried initial shell is baked, and after baking, a cleaned titanium alloy precision casting shell is obtained. The anhydrous alcohol and ethyl silicate are mixed at a weight ratio of (2~4):1 and stirred for 10-20 minutes to fully blend them to obtain the cleaning solution. The initial shell is centrifuged at a speed of 10-20 r / min; after the cleaning solution is injected, the initial shell is centrifuged for 20-40 minutes and then stopped.

2. The cleaning method for titanium alloy precision casting shells according to claim 1, characterized in that, Also includes: Before driving the initial shell to rotate, the excess dewaxing port of the initial shell is blocked so that the inner cavity of the initial shell has only one injection opening; after the initial shell stops rotating, the dewaxing port is opened to allow the cleaning fluid to drain naturally.

3. The cleaning method for titanium alloy precision casting shells according to claim 1, characterized in that, After draining the cleaning solution, the initial shell is placed in a constant temperature environment of 20-25°C and left to stand for at least 3 hours to dry the initial shell.

4. The cleaning method for titanium alloy precision casting mold shells according to claim 1, characterized in that, The baking process for the dried initial shell is as follows: the initial shell is moved from the constant temperature environment into the baking oven for baking at a temperature of 300-600℃ for 2-4 hours.

5. The cleaning method for titanium alloy precision casting shells according to claim 1, characterized in that, Filling the inner cavity of the initial shell with cleaning fluid specifically involves filling it with 100~300cm³ of cleaning fluid. 3 The cleaning fluid is injected into the initial shell at a flow rate of / s until the inner cavity is filled with the cleaning fluid.

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