A composite core for casting an aluminum alloy
By using a composite core structure, materials with different thermal conductivity, and a cooling module design, the solidification sequence of molten aluminum is optimized, solving the problem of local shrinkage porosity in aluminum alloy castings and improving the quality of the castings.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- CHONGQINGZHICHENG MACHINERY CO LTD
- Filing Date
- 2025-06-26
- Publication Date
- 2026-06-19
AI Technical Summary
In existing metal cores used for low-pressure casting of aluminum alloys, uneven solidification of molten aluminum leads to localized shrinkage porosity, affecting the quality of the casting.
A composite core structure is adopted, separating the core body and the forming module. The core body is made of a material with high thermal conductivity, while the forming module is made of a material with low thermal conductivity. They are connected by bolts. Combined with the design of the cooling module and heat insulation groove, the solidification sequence of the aluminum liquid is optimized.
It effectively reduces local shrinkage porosity in castings, improves the casting qualification rate, and enhances the heat preservation effect of the molding module and the cooling effect of the core body by controlling the solidification sequence of the aluminum liquid.
Smart Images
Figure CN224372734U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of cores, specifically to a composite core for aluminum alloy casting. Background Technology
[0002] In the low-pressure casting of aluminum alloy castings, the solidification sequence of the molten aluminum varies due to factors such as differences in wall thickness and core cooling. This can lead to localized shrinkage porosity in some castings. To improve the localized shrinkage porosity of some castings, it is necessary to optimize the cooling sequence of the molten aluminum.
[0003] An existing type of metal core installed on the upper mold is a one-piece structure made of the same material. The metal core has a cooling channel inside. During low-pressure casting, the aluminum liquid in contact with the front end of the metal core is easy to solidify first. However, for some castings, this solidification sequence will cause local shrinkage porosity, which will greatly increase the defect rate of the casting. Therefore, there is an urgent need for a metal core that can change the solidification sequence of aluminum liquid. Summary of the Invention
[0004] To address the aforementioned problems, this invention provides a composite core for aluminum alloy casting. By separating the forming module and the core body, and using a material with high thermal conductivity for the core body and a material with low thermal conductivity for the forming module, the molten aluminum in contact with the forming module solidifies more slowly, thus avoiding local shrinkage and porosity in the casting.
[0005] The technical solution of this utility model is as follows: a composite core for aluminum alloy casting, comprising a core body, a forming module, and a cooling module. The forming module is connected and fixed to the core body by multiple bolts. The core body has a cooling channel, and the cooling module is connected to the cooling channel. The end of the core body connected to the forming module has a positioning groove, and the end of the forming module connected to the core body has a positioning protrusion corresponding to the positioning groove. The positioning protrusion is inserted into the positioning groove to form a positioning. The forming module is made of a material with a thermal conductivity lower than that of the core body.
[0006] Preferably, the end of the core body connected to the molding module is provided with a heat insulation groove, the middle of the heat insulation groove is provided with a positioning groove, and the depth of the heat insulation groove is 0.5 to 1 mm.
[0007] Preferably, the gap between the outer periphery of the core body and the outer periphery of the molding module is less than 0.1 mm.
[0008] Preferably, the core body is provided with a plurality of axially penetrating bolt holes, and the molding module is provided with threaded blind holes corresponding to the bolt holes, and the bolts are fixedly connected to the threaded blind holes of the molding module by passing through the bolt holes of the core body.
[0009] Preferably, the cooling module includes a fixed base, on which a return water pipe, an inlet water pipe, and an inner pipe are fixedly connected. The inlet water pipe is connected to the inner pipe, and the inner pipe is located in a cooling channel. The diameter of the cooling channel is larger than the diameter of the inner pipe, so that a water passage gap is left between the inner pipe and the cooling channel. The cooling channel is connected to the return water pipe.
[0010] Preferably, the core body is made of mold steel, and the molding module is made of titanium alloy.
[0011] Preferably, the outer periphery of the end of the core body is provided with a toothed connecting portion.
[0012] Preferably, both the positioning groove and the positioning protrusion are polygonal.
[0013] The advantages of this utility model are:
[0014] 1. The molding module and the core body of this utility model are made of materials with significantly different thermal conductivity. The molding module conducts heat more slowly, which prolongs the solidification time of the molten aluminum in contact with the molding module. This is beneficial for optimizing the solidification sequence and reducing shrinkage porosity in the casting.
[0015] 2. In this utility model, a heat insulation groove is provided at one end of the core body connected to the molding module, which reduces the contact area between the molding module and the core body, increases the thermal resistance, hinders heat conduction, and significantly enhances the heat preservation effect of the molding module and the cooling effect of the core body. Attached Figure Description
[0016] Figure 1 This is a schematic diagram of the structure of this utility model;
[0017] Figure 2 for Figure 1 BB cross-sectional view. Detailed Implementation
[0018] See Figures 1 to 2A composite core for aluminum alloy casting includes a core body 1, a forming module 2, and a cooling module 3. The core body 1 has multiple axially penetrating bolt holes 14, and the forming module 2 has threaded blind holes 22 corresponding to the bolt holes 14. Bolts are used to fix the core body 1 through the bolt holes 14 and the forming module 2 through the threaded blind holes 22. In this embodiment, three bolts are used for fixing, which is sufficient to ensure the connection strength between the forming module 2 and the core body 1. The core body 1 is provided with a cooling channel 11. The cooling module 3 is connected to the cooling channel 11. The cooling module 3 includes a fixed base 31. A return water pipe 32, an inlet water pipe 33, and an inner pipe 34 are fixedly connected to the fixed base 31. The inlet water pipe 33 is connected to the inner pipe 34. The inner pipe 34 is located in the cooling channel 11. The diameter of the cooling channel 11 is larger than the diameter of the inner pipe 34, so that there is a water passage gap between the inner pipe 34 and the cooling channel 11. The cooling channel 11 is connected to the return water pipe 32. By supplying a cooling medium, such as cold water, to the inlet water pipe 33, the aluminum liquid in the area of the core body 1 can be rapidly cooled and solidified. The core body 1 is connected to the molding module 2 at one end with a positioning groove 12. The molding module 2 is connected to the core body 1 at the other end with a positioning protrusion 21 corresponding to the positioning groove 12. The positioning protrusion 21 is inserted into the positioning groove 12 to form a positioning. Both the positioning groove 12 and the positioning protrusion 21 are polygonal. In this embodiment, both the positioning groove 12 and the positioning protrusion 21 are quadrilateral. The purpose of this setting is to limit the molding module 2. When the positioning protrusion 21 is inserted into the positioning groove 12, the molding module 2 cannot rotate relative to the core body 1, which facilitates the connection and fixation of the molding module 2 and the core body 1. The core body 1 is connected to the molding module 2 at one end with a heat insulation groove 4. A positioning groove 12 is provided in the middle of the heat insulation groove 4. The depth of the heat insulation groove 4 is 0.5–1 mm. After the molding module 2 is connected and fixed to the core body 1, a heat insulation gap is formed between the molding module 2 and the core body 1 through the heat insulation groove 4. This reduces the contact area between the molding module 2 and the core body 1, increases thermal resistance, and ensures that the heat from the molding module 2 cannot be easily transferred to the core body 1 for heat conduction, significantly enhancing the heat preservation effect of the molding module 2 and the cooling effect of the core body 1. The gap 5 between the outer periphery of the core body 1 and the outer periphery of the molding module 2 is less than 0.1 mm to prevent molten aluminum from flowing in. The molding module 2 is made of a material with a lower thermal conductivity than that of the core body 1. Preferably, the core body 1 is made of mold steel, and the molding module 2 is made of titanium alloy. The thermal conductivity of mold steel is approximately 4–5 times that of titanium alloy, thus ensuring that the solidification time of the molten aluminum in the area of the molding module 2 is extended, while the molten aluminum in the area of the core body 1 solidifies preferentially. The outer periphery of the end of the core body 1 is provided with a toothed connecting part 13, and the core is fixed to the upper mold through the toothed connecting part 13.
[0019] The above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Any modifications made to the present utility model by those skilled in the art without departing from the spirit of the present utility model shall fall within the protection scope of the present utility model.
Claims
1. A composite core for aluminum alloy casting, characterized in that: The assembly includes a core body (1), a molding module (2), and a cooling module (3). The molding module (2) is connected and fixed to the core body (1) by multiple bolts. The core body (1) is provided with a cooling channel (11). The cooling module (3) is connected to the cooling channel (11). The end of the core body (1) connected to the molding module (2) is provided with a positioning groove (12). The end of the molding module (2) connected to the core body (1) is provided with a positioning protrusion (21) corresponding to the positioning groove (12). The positioning protrusion (21) is inserted into the positioning groove (12) to form a positioning. The molding module (2) is made of a material with a thermal conductivity lower than that of the core body (1).
2. The composite core for aluminum alloy casting according to claim 1, characterized in that: The core body (1) is connected to the molding module (2) at one end, which is provided with a heat insulation groove (4). The heat insulation groove (4) is provided with a positioning groove (12) in the middle, and the depth of the heat insulation groove (4) is 0.5-1mm.
3. The composite core for aluminum alloy casting according to claim 1, characterized in that: The gap (5) between the outer periphery of the core body (1) and the outer periphery of the molding module (2) is less than 0.1 mm.
4. The composite core for aluminum alloy casting according to claim 1, characterized in that: The core body (1) is provided with multiple axially penetrating bolt holes (14), and the molding module (2) is provided with threaded blind holes (22) corresponding to the bolt holes (14). The bolts pass through the bolt holes (14) of the core body (1) and are fixedly connected to the threaded blind holes (22) of the molding module (2).
5. A composite core for aluminum alloy casting according to claim 1, characterized in that: The cooling module (3) includes a fixed base (31), on which a return water pipe (32), an inlet water pipe (33), and an inner pipe (34) are fixedly connected. The inlet water pipe (33) is connected to the inner pipe (34), and the inner pipe (34) is located in the cooling channel (11). The diameter of the cooling channel (11) is larger than the diameter of the inner pipe (34), so that there is a water passage gap between the inner pipe (34) and the cooling channel (11). The cooling channel (11) is connected to the return water pipe (32).
6. The composite core for aluminum alloy casting according to claim 1, characterized in that: The core body (1) is made of mold steel, and the molding module (2) is made of titanium alloy.
7. A composite core for aluminum alloy casting according to claim 1, characterized in that: The core body (1) has a toothed connecting part (13) on the outer periphery of its end.
8. A composite core for aluminum alloy casting according to claim 1, characterized in that: Both the positioning groove (12) and the positioning protrusion (21) are polygonal.