Forming process of microminiature titanium alloy wireless earphone casting in 3C field

Abstract

The invention relates to the technical field of investment casting processes, in particular to a forming process of a microminiature titanium alloy wireless earphone casting in the 3C field. S2, the wax mold is installed and welded; s3, coating dip-coating; s4, assembling and welding the wax mold and the pouring gate; s5, making a shell; s6, forming and pouring are conducted; and S7, shell cleaning is conducted on the poured mold shell. By using the combination of the straight pouring gate, the plurality of transverse pouring gates and the inner pouring gate, the inner pouring gate adopts a combined composite assembling mode of the combination of the inner straight pouring gate and the plurality of inner transverse pouring gates, and molten metal flows in a mold cavity under the centrifugal effect and is smoothly filled. Through production verification, the forming rate of the micro-miniature complex thin-wall titanium alloy part cast through the method reaches 100% at most, and the phenomenon of insufficient casting does not occur.

Description

Technical Field

[0001] The present invention relates to the technical field of investment casting processes, and particularly to a forming process for micro-miniature titanium alloy wireless earphone castings in the 3C field. Background Art

[0002] In recent years, due to the popularization of titanium in the civilian field, the application research in digital electronics, medical, sports goods, etc. has begun to increase, such as wireless earphones, wireless lapel microphones, prosthetics, golf club heads, etc. They have high requirements for the accuracy and performance of titanium alloy processed parts. The micro-miniature wireless earphones in the 3C field are characterized by being micro-miniature (scale classification: 0.5 mm - 10 mm), delicate, complex, and ultra-thin wall (scale classification: < 1 mm). Among them, the wall thickness of the earphone shell piece is 0.7 mm, the width of the slender slot in the wire groove is 0.7 mm, and the length is 30 mm. There are Φ1 mm micropores and Φ1 mm sharp corners distributed at an interval of 1 mm on its back. The surface accuracy requirement of casting is not allowed to exceed 3.2 μm, and the casting difficulty is great. For the forming of thin-walled castings, investment precision casting is usually selected. However, for the forming of such micro-miniature, delicate, complex, and ultra-thin wall titanium alloy parts, there are the following problems: First, the shell making of slender slots and micropores is difficult, and there are easily slag inclusions and titanium bead defects; second, the overall wall thickness is too thin, there are modeling details such as sharp corners and thin edges, and the fluidity of titanium alloy is poor, so it is not easy to fill the mold completely, and the forming rate of parts is extremely low; third, the shell pieces are prone to vibration and cracking during the shell cleaning process.

[0003] Publication No.: CN101143381B Titanium alloy precision casting melting method, including shell making after the wax pattern (1), then dewaxing, shell making baking, pouring, and post-treatment. Shell making baking: Using a refractory silica sol coating layer for shell making, the refractory filler is a mixture powder of 95% yttrium oxide and 5% zirconium oxide. The mixture of 95% yttrium oxide and 5% zirconium oxide is processed by electrofusion and then crushed into a powder with a mesh size of 325. However, in this solution, the wax pattern (1) is not assembled by welding, and the overall production efficiency is low, and it cannot solve the problems of low quality and production efficiency in the investment casting process of multiple micro-miniature size workpieces.

[0004] Therefore, it is necessary to study a precision casting method for micro-miniature titanium alloy wireless earphones in the 3C field to solve the bottleneck problem of the precision batch forming process of micro-miniature titanium alloy wireless earphones, improve product quality and production efficiency, and also provide technical support for the requirements of micro-miniature precision parts in the electronic digital field. Summary of the Invention

[0005] In view of this, the present invention aims to propose a forming process for micro-miniature titanium alloy wireless earphone castings in the 3C field to solve the problems of low quality and production efficiency in the investment casting process of multiple micro-miniature size workpieces.

[0006] In the present invention, the surface shell of the titanium alloy casting needs to maintain a low interfacial reaction activity and high thermal stability with the high-temperature titanium liquid, which requires higher chemical inertness and strength of each component of the surface layer material. The main titanium alloy surface layer binders are the zirconium acetate series and the silicon oxide series. Both binders are applicable for the production of general titanium alloy castings. However, when producing complex thin-walled titanium alloy investment castings, neither of the two binders meets the usage requirements. Specifically: for the zirconium acetate binder, its strength is low, and it is easily redissolved when exposed to moisture or water, ultimately resulting in slag falling off the casting; for the silicon oxide binder, the thickness of the pollution layer generated by its reaction with the titanium liquid is relatively large, and the casting is prone to cracking, which does not meet the requirements of complex thin-walled titanium alloy investment castings. The novel strengthening glue prepared by modifying ordinary silica sol by adding reinforcing agents and stabilizers is adopted in the present invention to prepare the surface layer coating, which is more suitable for the preparation of the surface shell of thin-walled complex titanium alloy castings, will not cause pollution to the titanium alloy during the high-temperature pouring process, and the appearance quality of the blank is high.

[0007] The technical solution of the present invention is realized as follows:

[0008] The present invention discloses a forming process for micro-miniature titanium alloy wireless earphone castings in the 3C field, which specifically includes the following steps:

[0009] S1: Making the wax pattern;

[0010] S2: Assembling and welding the wax pattern, and welding the wax pattern group to the ingate;

[0011] S3: Dip coating, soaking the wax pattern and the ingate, which are assembled and welded into a group of wax pattern trees, in the coating to form a smooth surface coating;

[0012] S4: Assembling and welding the wax pattern and the runner, and welding multiple groups of the wax pattern trees after dip coating and drying to the wax pattern mold;

[0013] S5: Shell making, subjecting the welded wax pattern mold to surface layer and backing layer shell making;

[0014] S6: Assembling the mold and pouring, connecting the mold shell of the mold to the pouring system of centrifugal pouring;

[0015] S7: Cleaning the mold shell after pouring.

[0016] Further, in step S1, the wax pattern is made using a metal mold or 3D printing.

[0017] Further, in step S2, the size of the ingate is designed according to the size of the wax pattern. The ingate includes one straight ingate and multiple transverse ingates. The multiple transverse ingates are vertically arranged on the straight ingate, and two wax patterns are assembled and welded to one transverse ingate.

[0018] Further, in step S3, it includes the following steps:

[0019] S31: Immerse the wax pattern tree for 10 - 30 s;

[0020] S32: After the wax pattern tree is fully soaked, take it out, and use an air gun to blow away the excess slurry on the surface. Do not blow directly at the wax pattern.

[0021] S33: Dry naturally. The environmental humidity range is 80 - 90%, the temperature range is 25 ± 2°C, and the drying time is more than 18 h.

[0022] Furthermore, in step S3, the raw materials for coating preparation are silica sol - modified strengthening glue and 325 - mesh yttrium powder, and the powder - liquid ratio for preparing the coating is 4.2 - 4.5.

[0023] Furthermore, in step S4, the wax pattern mold frame includes a sprue and multiple long cross - runners. The long cross - runners are vertically arranged on the sprue. The width of the long cross - runner should be greater than the diameter of the inner sprue in the ingate. Welding surfaces are provided at both ends of the long cross - runner, and the welding surfaces are arranged at an acute angle to the long cross - runner.

[0024] Furthermore, 3 - 4 long cross - runners are provided, and the widths of the multiple long cross - runners gradually increase from top to bottom.

[0025] Furthermore, in step S5, the shell making process goes through dewaxing and roasting to obtain the mold frame shell with a certain strength, and the number of shell making layers is 5 - 7 layers.

[0026] Furthermore, in step S6, the process parameters of centrifugal casting are counter - clockwise rotation, the rotation speed is 180 - 230 r / min, and casting is carried out in a vacuum negative pressure environment.

[0027] Furthermore, in step S7, an artificial hammering and vibration method is adopted. Manually strike the sprue part of the mold frame to remove the mold shell at the runner part, and then remove the mold shell on the fine structure of the casting surface through sandblasting.

[0028] Compared with the prior art, the forming process of a micro - sized titanium alloy wireless headphone casting in the 3C field of the present invention has the following advantages:

[0029] 1. By using the combined type of "the sprue - multiple cross - runners - the ingate" in the present invention, and the ingate adopts the combined type of "the inner sprue - multiple inner cross - runners", the metal liquid flows smoothly in the cavity under the centrifugal action. Through production verification, the forming rate of the micro - sized complex thin - wall titanium alloy parts cast by using this method reaches up to 100% at most, and there is no under - casting phenomenon.

[0030] 2. Before preparing the surface layer by investment casting, the present invention first adopts the process of soaking in silica sol for pretreatment. The surface of the part is strengthened, improving the strength and smoothness of the surface layer. After roasting, the surface of the shell mold is smooth, and there are no cracks on the surface layer, completely and clearly replicating the fine shape of the wax mold of the casting. Therefore, the surface details of the micro-sized titanium alloy parts after pouring are clear, smooth, pollution-free, and have a low surface roughness.

[0031] 3. The present invention uses manual hammering to impact the main runner position of the mold frame to clean large pieces of the shell mold, and the shell mold on the surface of the internal cross runner and the micro-sized casting is cleaned by sandblasting. There are no cracks or damages on the casting after shell cleaning.

[0032] 4. By using this forming method, up to 640 wireless earphone castings can be cast in one furnace, which can greatly improve the production efficiency, save the casting cost, and improve the metal utilization rate. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] The accompanying drawings constituting a part of the present invention are used to provide a further understanding of the present invention. The schematic embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation to the present invention. In the drawings:

[0034] Figure 1 is a schematic diagram of the welded structure of the internal runner of the wax mold of the present invention;

[0035] Figure 2 is a schematic diagram of the welded structure of the runner of the wax mold of the present invention;

[0036] Figure 3 is a side view of the welded structure of the runner of the wax mold of the present invention;

[0037] Figure 4 is a schematic diagram of the centrifugal casting mold assembly of the present invention.

[0038] 1. Wax mold; 2. Internal cross runner; 3. Internal straight runner; 4. Long cross runner; 5. Straight runner; 6. Wax mold tree; 7. Wax mold frame; 8. Internal runner; 9. Mold frame shell mold. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0039] In order to make the technical means, objectives and effects of the present invention easy to understand, the embodiments of the present invention will be described in detail below with reference to specific drawings.

[0040] It should be noted that all terms indicating directionality and positionality in the present invention, such as "upper", "lower", "left", "right", "front", "rear", "vertical", "horizontal", "inner", "outer", "top", "bottom", "lateral", "longitudinal", "center", etc., are only used to explain the relative positional relationship and connection situation between components in a specific state, and are only for the convenience of describing the present invention, rather than requiring the present invention to be constructed and operated in a specific orientation. Therefore, it should not be construed as a limitation to the present invention. Additionally, the descriptions involving "first", "second", etc. in the present invention are only for descriptive purposes, and should not be construed as indicating or implying their relative importance or implicitly specifying the quantity of the indicated technical features.

[0041] In the description of the present invention, unless otherwise clearly specified and defined, the terms "installed", "connected", and "coupled" shall be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection; it can be directly connected, or indirectly connected through an intermediate medium, and can be the communication inside two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0042] In the description of this specification, the descriptions with reference to terms such as "one embodiment", "some embodiments", "schematic embodiments", "examples", "specific examples", or "some examples", etc. mean that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in a suitable manner in any one or more embodiments or examples.

[0043] The present invention discloses a forming process for a micro-miniature titanium alloy wireless headphone casting in the 3C field, specifically including the following steps:

[0044] S1: Making of the wax pattern 1;

[0045] Make the wax pattern 1 that is consistent with the shape of the final casting. The wax pattern 1 is easy to process and can accurately replicate complex structures.

[0046] S2: Group welding of the wax pattern 1, welding the wax pattern 1 to the ingate 8;

[0047] Weld the wax pattern 1 to the ingate 8 to form a part of the gating system, ensure the smooth flow of the molten metal into the cavity, reduce defects, and at the same time, multiple castings can be processed at one time, which is convenient for subsequent coating and helps to improve production efficiency.

[0048] S3: Dip coating with paint. The wax patterns 1 and the ingates 8 are welded into a group of wax pattern trees 6 and then soaked in the paint to form a smooth surface coating.

[0049] Before preparing the surface layer by investment casting, the pre-treatment is carried out by using the process of soaking in silica sol. The surface of the casting is strengthened, which improves the strength and smoothness of the surface layer. After roasting, the surface of the shell mold is smooth and there are no cracks on the surface layer. It completely and clearly replicates the fine shape of the wax pattern 1, reduces the difficulty of making the shell for slender slits and micropores, and avoids defects such as slag inclusion and titanium beads.

[0050] S4: Welding the wax patterns 1 and the runners. After the dip coating and drying, multiple wax pattern trees 6 are welded to the wax pattern mold 7.

[0051] Welding multiple wax pattern trees 6 to the wax pattern mold 7 to form an integral structure. Using this forming method, up to 640 wireless earphone castings can be cast in one furnace, which can greatly improve the production efficiency, save the casting cost, and improve the metal utilization rate.

[0052] S5: Making the shell mold. The welded wax pattern mold 7 undergoes shell mold making for the surface layer and the backing layer.

[0053] Through shell mold making for the surface layer and the backing layer, a strong shell mold is formed, which helps to enhance the high-temperature resistance and mechanical strength of the shell mold and ensure the quality of the casting.

[0054] S6: Assembling the mold and pouring. Connect the mold shell 9 of the mold frame to the pouring system of centrifugal pouring.

[0055] Connect the mold shell 9 of the mold frame to the centrifugal pouring system for metal pouring, which improves the metal filling property, reduces gas holes and shrinkage porosity, ensures complete filling of the casting in the mold cavity, and effectively improves the forming rate of the casting.

[0056] S7: Cleaning the mold shell after pouring.

[0057] With this setup, through the improved ingate design, pre-treatment by soaking in silica sol before preparing the surface layer, and the centrifugal pouring method, the combined type of "downsprue 5 - multiple cross runners - ingate 8" is used, and the ingate 8 adopts the combined type of "inner downsprue 3 - multiple inner cross runners 2" for the composite mold assembling method. Under the centrifugal action, the molten metal flows smoothly in the mold cavity for filling, so that the forming rate of the micro - sized complex thin - walled titanium alloy parts reaches 100%, and there is no under - pouring phenomenon. Using a specific formula of paint and strict dip coating and drying processes, the smoothness and cleanliness of the casting surface are improved, the production efficiency is greatly enhanced, and the cost is reduced.

[0058] Specifically, in step S1, a metal mold or 3D printing is used to make the casting wax pattern 1.

[0059] Whether using metal molds or 3D printing technology, it is possible to highly accurately replicate the designed casting shape, ensuring the accuracy of the final product. Using 3D printing technology is particularly suitable for producing castings with complex and delicate structures, capable of quickly responding to design changes and supporting customized production. For small batch production or prototype manufacturing, 3D printing can directly generate wax patterns 1 from digital models, eliminating the time and cost of traditional mold manufacturing.

[0060] This setting can meet the accuracy requirements of micro-miniature titanium alloy wireless headphone castings, such as a surface accuracy requirement of no more than 3.2 μm, reducing the manufacturing difficulty of castings with complex structures such as slender slits, micropores, sharp corners, and thin edges, and reducing the preparation time and cost.

[0061] Specifically, in step S2, the size of the ingate 8 is designed according to the size of the wax pattern 1. The ingate 8 includes one straight ingate 3 and multiple cross ingates 2. The cross ingates 2 are vertically arranged on the straight ingate 3, and two wax patterns 1 are welded together by one cross ingate 2.

[0062] Preferably, the spacing between adjacent cross ingates 2 is greater than 5 mm, and the diameter of the cross ingate 2 should be smaller than the diameter of the straight ingate 3.

[0063] By reasonably designing the size and layout of the straight ingate 3 and the cross ingates 2, the flow of the molten metal can be effectively guided to each wax pattern 1, ensuring complete filling, reducing defects such as slag inclusion and titanium beads that may occur during the casting process, and improving the quality of the casting. Welding two wax patterns 1 together by one cross ingate 2 and maintaining an appropriate spacing, greater than 5 mm, helps ensure that each casting can receive sufficient supply of molten metal, avoiding quality problems caused by insufficient filling.

[0064] This setting can significantly improve the forming success rate of micro-miniature complex thin-walled titanium alloy parts by precisely controlling the size and distribution of the ingate 8, reducing the scrap caused by poor filling or gas holes, etc., reducing the production cost, increasing the number of castings produced in a single production, and improving the production efficiency.

[0065] Specifically, in step S3, it includes the following steps:

[0066] S31: Immerse the wax pattern tree 6 for 10 - 30 s;

[0067] S32: After the wax pattern tree 6 is fully soaked, take it out and use an air gun to blow away the excess slurry on the surface. Do not blow directly at the wax pattern 1.

[0068] S33: Natural drying, with the environmental humidity range of 80 - 90% and the temperature range of 25 ± 2 °C, and the drying time is more than 18 h.

[0069] The wax pattern tree 6 is immersed in a special slurry, which will form a uniform coating on the surface of the wax pattern 1. This coating will become the mold for the outer layer of the casting during the subsequent casting process. After the wax pattern tree 6 is fished out, there may be accumulated excess slurry on its surface. An air gun can effectively remove this excess material, ensuring the smoothness and flatness of the coating, while reducing the possible formation of defects. The air gun should not be directly blown at the wax pattern 1 to avoid damaging the already formed coating or causing uneven coating thickness. Specific temperature and humidity conditions help the slurry coating to dry slowly and evenly, thus reducing the risk of cracks or other forms of damage. A longer drying time ensures that the coating is thoroughly dried, which helps to obtain high-quality castings.

[0070] This setting can improve the surface quality of the casting and enhance the mechanical properties of the casting, such as strength and wear resistance.

[0071] Specifically, in step S3, the raw materials for coating preparation are silica sol-modified strengthening glue and 325-mesh yttrium powder, and the powder-liquid ratio for preparing the coating is 4.2 - 4.5.

[0072] The silica sol-modified strengthening glue can improve the adhesion between the coating and the wax pattern 1, ensuring that the coating will not fall off or crack during subsequent processes such as drying and roasting. As a high-temperature resistant material, adding yttrium powder to the coating can significantly improve the fire resistance of the coating, protecting the mold shell from being eroded by high-temperature molten metal. By precisely controlling the powder-liquid ratio of 4.2 - 4.5, it can ensure that the coating has sufficient thickness to provide necessary protection, and will not be too thick to cause dimensional deviation or other casting defects.

[0073] This setting can achieve high surface finish, reduce the need for subsequent processing, improve the yield rate, and help reduce the possibility of defects such as slag inclusion and porosity on the surface of the casting. This coating formula can effectively support the investment mold and maintain a stable shape during roasting and pouring, thus improving the forming success rate of micro-miniature complex thin-walled titanium alloy parts.

[0074] Specifically, in step S4, the wax pattern mold frame 7 includes a sprue 5 and multiple long cross gates 4. The long cross gates 4 are vertically arranged on the sprue 5. The width of the long cross gate 4 should be greater than the diameter of the inner sprue 3 in the ingate 8. Welding surfaces are provided at both ends of the long cross gate 4, and the welding surfaces are arranged at an acute angle to the long cross gate 4.

[0075] By setting the sprue 5 and multiple long cross gates 4, the molten metal can be effectively guided to each wax pattern 1, ensuring complete and uniform filling. The design that the width of the long cross gate 4 is greater than the diameter of the inner sprue 3 in the ingate 8 helps to increase the flow area of the molten metal and reduce the problem of insufficient filling caused by poor fluidity. The acute angle between the welding surface and the long cross gate 4 makes the wax pattern tree 6 tilt outward after welding, which helps to reduce the distance between adjacent long cross gates 4 and reduce the overall volume.

[0076] This setting is conducive to the rapid and stable flow of the molten metal into each wax mold 1, thereby improving the filling efficiency and quality, reducing the occurrence probability of casting defects such as porosity and slag inclusions. Because the wider channels reduce the flow resistance of the molten metal, reduce the possibility of turbulence, and improve the production efficiency.

[0077] Preferably, 3 - 4 long horizontal runners 4 are provided, and the widths of the multiple long horizontal runners 4 gradually increase from top to bottom.

[0078] By providing 3 - 4 long horizontal runners 4 and making their widths gradually increase from top to bottom to adapt to centrifugal casting, it can better guide the molten metal to flow from the sprue 5 to each wax mold 1, help regulate the flow rate of the molten metal, and ensure that each casting can be filled evenly and sufficiently. As the molten metal flows in from the sprue 5 and flows downward, the gradually increasing long horizontal runners 4 can effectively disperse the pressure, avoiding casting defects caused by local overpressure, such as porosity and slag inclusions.

[0079] This setting helps to control the flow rate of the molten metal, prevent turbulence or splashing caused by high - speed flow, reduce the occurrence of common casting defects such as porosity and slag inclusions, and increase the possibility of the molten metal reaching each wax mold 1. This is particularly important when processing micro - sized, complex, thin - walled titanium alloy parts, and can significantly improve the forming success rate.

[0080] Specifically, in step S5, the shell - making process undergoes dewaxing and roasting to obtain a mold frame shell 9 with a certain strength, and the number of shell - making layers is 5 - 7 layers.

[0081] By repeatedly coating refractory materials and drying and roasting, a solid shell can be formed outside the wax mold 1. This shell needs to be able to withstand the high temperature of the molten metal without deforming or cracking. The dewaxing step melts and flows out the internal wax mold 1, leaving a cavity for subsequent pouring. This step ensures the accuracy of the final casting shape. Multiple coatings increase the thickness and strength of the shell, ensuring that it can remain stable when the molten metal is poured in and does not crack or deform.

[0082] The setting of 5 - 7 shell - making layers not only ensures sufficient strength to support the pressure of the molten metal but also avoids thermal stress concentration or other defects caused by excessive thickness, thereby improving the quality and forming success rate of the casting, reducing unnecessary material waste and processing time, and lowering the production cost.

[0083] Specifically, in step S6, before assembling the mold, use a vacuum cleaner to remove the ash powder and the like on the surface of the shell mold and the graphite runner, and inspect the appearance.

[0084] Using a vacuum cleaner can effectively remove dust, particles and other impurities on the surface of the shell mold and graphite runner, avoiding the mixing of these impurities into the molten metal to form inclusions, reducing the occurrence of defects on the surface of the casting, such as gas holes, slag inclusions, etc. Conducting an appearance inspection on the shell mold and runner before assembly can promptly detect and repair any problems that may affect the casting quality, such as cracks, breakages or other structural defects.

[0085] This setting helps to reduce various defects that may occur during the casting process, and can also improve production efficiency and the yield rate, ensuring that each casting can meet the design requirements.

[0086] Specifically, in step S6, the process parameters of centrifugal casting are counterclockwise rotation, with a rotational speed of 180 - 230 r / min, and casting is carried out under a vacuum negative pressure environment.

[0087] By setting a specific rotation direction and speed, the centrifugal force can be effectively utilized to prompt the molten metal to quickly and evenly fill the entire cavity, especially for parts that are difficult to fill, such as complex structures or slender slits. Casting under a vacuum negative pressure environment can effectively remove air and other gases in the cavity, reduce the gas hole defects caused by gas residue, and at the same time help to remove gases and impurities in the molten metal. The action of the centrifugal force can better compact the molten metal, thereby obtaining a denser casting structure and improving the mechanical properties of the casting, such as strength, hardness, etc.

[0088] This setting can ensure that the molten metal flows at the optimal speed, avoiding problems such as excessive turbulence caused by too fast flow or insufficient filling caused by too slow flow, thereby improving the forming quality and consistency of the casting, greatly reducing the occurrence probability of internal defects such as gas holes and shrinkage porosity, ensuring the purity and integrity of the internal structure of the casting, and enabling the manufacture of micro - sized titanium alloy castings with complex geometric shapes and thin - wall features.

[0089] Specifically, in step S7, an artificial hammering vibration method is adopted. Manually strike the straight runner 5 of the mold base to remove the mold shell at the runner part, and then remove the mold shell on the surface of the casting with fine structures through sandblasting.

[0090] Using artificial hammering to impact the position of the main runner of the mold base to clean the large - piece mold shell avoids directly applying too large an impact force to the casting, thereby reducing the risk of casting damage caused by improper operation. The mold shell on the inner cross - runner 2 and the surface of the micro - sized casting is cleaned thoroughly by sandblasting, especially in places that are difficult to reach, such as fine structures, slits or sharp corners. After shell cleaning, the casting has no cracks or damages.

[0091] This setting quickly removes most of the mold shell by artificial hammering and then uses sandblasting for fine repair, improving the overall cleaning speed, making the entire shell - cleaning process fast and efficient, and maximizing the protection of the integrity and surface quality of the casting.

[0092] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included within the protection scope of the present invention.

Claims

1. A molding process for a miniature titanium alloy wireless headset casting in the 3C field, characterized in that: The specific steps include: S1: wax model (1) preparation; S2: Assembling and welding the wax mold (1), and welding the wax mold (1) to the ingrown (8); S3: coating with a coating, welding the wax model (1) and the ingates (8) together to form a set of wax model trees (6) and then coating them to form a coating with a smooth surface; S4: assembling and welding the wax model (1) and the runner, and assembling and welding the plurality of wax model trees (6) after dip coating and drying to the wax model frame (7); S5: Shell making, the wax mold frame (7) after assembly and welding is subjected to surface layer and back layer shell making; S6: forming and pouring, connecting the mold frame shell (9) to the pouring system of centrifugal pouring; S7: Cleaning the mold shell after pouring.

2. The molding process of the 3C field miniature titanium alloy wireless headset casting according to claim 1 is characterized in that: In step S1, the wax model (1) is made using a metal mold or 3D printing.

3. The molding process of the 3C field miniature titanium alloy wireless headset casting according to claim 1 is characterized in that: In step S2, the size of the endogate (8) is designed according to the size of the wax mold (1), and the endogate (8) includes an inner straight runner (3) and a plurality of inner cross runners (2), wherein the plurality of inner cross runners (2) are vertically arranged on the inner straight runner (3), and one inner cross runner (2) is welded to two pieces of the wax mold (1).

4. The molding process of the 3C field miniature titanium alloy wireless headset casting according to claim 1 is characterized in that: In step S3, the following steps are included: S31: soaking the wax model tree (6) for 10 to 30 seconds; S32: After the wax model tree (6) is fully soaked, it is fished out and the excess slurry on the surface is blown away by an air gun, but the air blowing does not directly blow the wax model (1). S33: Natural drying, ambient humidity range is 80~90%, temperature range is 25±2℃, and drying time is more than 18h.

5. The molding process of the 3C field miniature titanium alloy wireless headset casting according to claim 1 is characterized in that: In step S3, the raw materials for preparing the coating are silica sol-modified reinforcing glue and 325 mesh yttrium powder, and the powder-liquid ratio of the coating is 4.2-4.

5.

6. The molding process of the 3C field miniature titanium alloy wireless headset casting according to claim 3 is characterized in that: In step S4, the wax mold frame (7) includes a straight runner (5) and a plurality of long cross runners (4), wherein the long cross runner (4) is vertically arranged on the straight runner (5), the width of the long cross runner (4) should be greater than the diameter of the inner straight runner (3) in the inner runner (8), and welding surfaces are arranged at both ends of the long cross runner (4), and the welding surfaces are arranged at an acute angle with the long cross runner (4).

7. The molding process of the 3C field miniature titanium alloy wireless headset casting according to claim 6 is characterized in that: The long horizontal runners (4) are provided in 3 to 4 sections, and the width of the multiple long horizontal runners (4) gradually increases from top to bottom.

8. The molding process of the 3C field miniature titanium alloy wireless headset casting according to claim 1 is characterized in that: In step S5, the shell is dewaxed and sintered to obtain the mold shell (9) with a certain strength, and the number of shell layers is 5-7.

9. The molding process of the 3C field miniature titanium alloy wireless headset casting according to claim 1, characterized in that: In step S6, the centrifugal casting process parameters are counterclockwise rotation, a rotation speed of 180-230 r / min, and casting in a vacuum negative pressure environment.

10. The molding process of the 3C field miniature titanium alloy wireless headset casting according to claim 6, characterized in that: In step S7, the mold frame is manually struck at the sprue (5) by manual hammering and vibration to remove the mold shell at the sprue part, and then the mold shell of the fine structure on the surface of the casting is removed by sandblasting.

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