Foamed ceramic
By designing foam ceramics with a wide upper and narrow upper porous structure and an arc-shaped transition surface, the problem of insufficient stress in the metal casting process of traditional foam ceramics is solved, the stability and stress strength are improved, and the quality of the casting is ensured.
Patent Information
- Application Number
- CN202421786957.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-07-25
- Publication Date
- 2025-06-13
- Estimated Expiration
- 2034-07-25
AI Technical Summary
Traditional foam ceramics are insufficient in the process of metal casting, which is prone to breakage and fall off during casting of high-temperature melts, resulting in casting defects.
A foam ceramic is designed, with a porous structure on the upper surface, lower surface and transition part, which is wide at the top and narrow at the bottom. The transition surface is an arc-shaped surface, which can fit with the inclined inner wall of the sand mold.
The structural stability and stress strength of foam ceramics are improved, and they can effectively support foam ceramics, prevent falling and ensure the quality of castings.
Smart Images
Figure CN222969412U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of foamed ceramics, in particular to a foamed ceramic. Background Art
[0002] Traditional foamed ceramics can be used in the melting process of metal casting as filters for metal solutions, and the method for preparing foamed ceramics is the organic precursor impregnation method. Traditional foamed ceramic filters are usually disc-shaped or flat-plate-shaped. When in use, the high-temperature melt is poured from the middle of the foamed ceramic. At this time, the middle part of the foamed ceramic bears a large impact force. Due to the poor overall mechanical strength of the disc-shaped or flat-plate-shaped structure and the insufficient supporting force of the lower sand mold on the foamed ceramic, the foamed ceramic is likely to directly fall into the casting with the melt after being damaged, thus causing defects in the casting. Summary of the Utility Model
[0003] The technical problem to be solved by the utility model is to provide a foamed ceramic that can improve the mechanical strength of the foamed ceramic and enhance the stability of the foamed ceramic.
[0004] To solve the above technical problem, the utility model provides a foamed ceramic, including an upper surface, a lower surface, and a transition part provided between the upper surface and the lower surface. Porous structures are provided in the upper surface, the lower surface, and the transition part.
[0005] The projected area of the upper surface on the horizontal plane is larger than the projected area of the lower surface on the horizontal plane. The side wall of the transition part is provided with a transition surface, and the transition surface is an arc surface.
[0006] As an improvement of the above solution, both the upper surface and the lower surface are horizontally arranged, and the projection of the lower surface on the horizontal plane can fall within the projection of the upper surface on the horizontal plane.
[0007] As an improvement of the above solution, the outer shapes of the upper surface and the lower surface are both circular, and the centers of the upper surface and the lower surface are located on the same vertical line.
[0008] As an improvement of the above solution, the transition part is frustum-shaped, and the transition surface is inclined to the horizontal plane.
[0009] As an improvement of the above solution, the included angle between the generatrix of the transition part and the horizontal plane ranges from 25° to 65°.
[0010] As an improvement of the above solution, the upper surface, the lower surface, and the transition part are provided with a plurality of filter holes with different shapes and sizes, and the plurality of filter holes are interconnected with each other so that the upper surface is communicated with the lower surface.
[0011] As an improvement of the above solution, the foam ceramic is in the shape of a frustum with a wider upper part and a narrower lower part, the transition surface is an inclined arc surface, and the transition surface can be fitted with the inner wall of the conical sand mold.
[0012] As an improvement of the above solution, the porosity of the foam ceramic is 60%-95%.
[0013] Implementing the present utility model has the following beneficial effects:
[0014] The foam ceramic of the present utility model is provided with an upper surface, a lower surface, and a transition part provided between the upper surface and the lower surface. Porous structures are provided in the upper surface, the lower surface, and the transition part to achieve a filtering effect. The projected area of the upper surface on the horizontal plane is larger than the projected area of the lower surface on the horizontal plane, presenting a structure with a wider upper part and a narrower lower part. The structure with a wider upper part and a narrower lower part can make the foam ceramic have better structural stability. While improving the stress strength, it can be fitted with the inclined inner wall of the sand mold. During the pouring process, the lower sand mold will generate an obliquely upward acting force on the foam ceramic, thereby being able to hold up the foam ceramic and enhance the stability of the foam ceramic. Moreover, a transition surface is provided on the side wall of the transition part, and the transition surface is an arc surface. The arc surface structure is more conducive to uniform stress, further improving the stability of the foam ceramic. Description of the Drawings
[0015] Figure 1 is a schematic structural diagram of the foam ceramic and the sand mold of the present utility model;
[0016] Figure 2 is a schematic diagram of the inclination angle of the generatrix of the foam ceramic of the present utility model;
[0017] Figure 3 is a schematic structural diagram of the foam ceramic of the present utility model. Detailed Embodiments
[0018] To make the objectives, technical solutions, and advantages of the present utility model clearer, the present utility model will be further described in detail below with reference to the drawings. Just for clarification, the orientation terms such as upper, lower, left, right, front, back, inner, and outer that appear or will appear in the text of the present utility model are only based on the drawings of the present utility model, and they do not specifically limit the present utility model.
[0019] See Figure 1 and Figure 3, an embodiment of the present utility model discloses a foam ceramic 10, which includes an upper surface 1, a lower surface 2, and a transition portion 3 provided between the upper surface 1 and the lower surface 2. A porous structure is provided in each of the upper surface 1, the lower surface 2, and the transition portion 3. The foam ceramic is made by an impregnation method. Specifically, a precursor is impregnated in a slurry, and the foam ceramic 10 can be obtained through drying and sintering. There are many filter holes 4 inside the foam ceramic 10, which can play a filtering role in metal casting. When the foam ceramic 10 is in use, it needs to be placed in a sand mold 20, and then a melt is poured onto the foam ceramic 10 from top to bottom. The melt falls from the upper surface 1 of the foam ceramic 10 to the lower surface 2. In this way, the middle part of the foam ceramic 10 will exert a downward force on the sand mold 20. Traditional foam ceramics 10 use regular structures such as disc-shaped or flat-plate-shaped ones, and are prone to fall from the sand mold 20 after being damaged and deformed, thus affecting the formed casting. In the embodiment of the present utility model, the porous structures provided in the upper surface 1, the lower surface 2, and the transition portion 3, wherein the projected area of the upper surface 1 on the horizontal plane is larger than the projected area of the lower surface 2 on the horizontal plane, and the foam ceramic 10 presents a structure that is wider at the top and narrower at the bottom. This structure has better structural strength and can be better supported in the sand mold 20. When exerting a downward force on the sand mold 20 from top to bottom, the sand mold 20 will generate an inclined upward reaction force on the inclined wall surface of the foam ceramic 10. This inclined upward reaction force can ensure that the foam ceramic 10 is not easily dropped and guarantees the stability of the foam ceramic 10. Moreover, the side wall of the transition portion 3 is provided with a transition surface 31, and the transition surface 31 is an arc surface. The arc surface can make the inclined upward reaction force acting on the side wall of the foam ceramic 10 more uniform, further ensuring stability.
[0020] The beneficial effects of the embodiment of the present utility model are as follows:
[0021] In the embodiment of the present utility model, the foam ceramic 10 is provided with an upper surface 1, a lower surface 2, and a transition portion 3 disposed between the upper surface 1 and the lower surface 2. The upper surface 1, the lower surface 2, and the transition portion 3 are all provided with porous structures to achieve a filtering effect. The projected area of the upper surface 1 on the horizontal plane is larger than the projected area of the lower surface 2 on the horizontal plane, presenting a structure that is wider at the top and narrower at the bottom. The structure that is wider at the top and narrower at the bottom enables the foam ceramic 10 formed by the foam ceramic to have better structural stability. While improving the stress strength, it can fit with the inclined inner wall of the sand mold 20. During the pouring process, the lower sand mold 20 will generate an upwardly inclined acting force on the foam ceramic 10, thereby being able to support the foam ceramic 10 and enhance the stability of the foam ceramic 10. Moreover, the side wall of the transition portion 3 is provided with a transition surface 31, and the transition surface 31 is an arc surface. The structure of the arc surface is more conducive to uniform stress, further improving the stability of the foam ceramic 10.
[0022] Specifically, both the upper surface 1 and the lower surface 2 are horizontally arranged. The horizontal arrangement is beneficial for the upper surface 1 and the lower surface 2 to be placed flat in the sand mold 20, and at the same time ensures that the molten metal that falls can be evenly dispersed into each part of the foam ceramic 10 without tilting. The projection of the lower surface 2 on the horizontal plane can fall within the projection of the upper surface 1 on the horizontal plane, that is, the area of the upper surface 1 is larger than the area of the lower surface 2, and at least the edge part of the upper surface 1 can protrude from the edge of the lower surface 2, thereby providing a basis for forming a structure that is wider at the top and narrower at the bottom.
[0023] Furthermore, the outer shapes of both the upper surface 1 and the lower surface 2 are circular, the centers of the upper surface 1 and the lower surface 2 are located on the same vertical line, the foam ceramic 10 is a solid of revolution, the upper surface 1 and the lower surface 2 are concentrically arranged, and the formed foam ceramic 10 forms a circumferentially symmetric solid of revolution structure. On the one hand, it can make the flow of the poured molten metal more uniform, and on the other hand, it can make the reaction force of the sand mold 20 on the foam ceramic 10 more uniform.
[0024] See Figure 2, the transition part 3 is frustum-shaped, the transition surface 31 is inclined with respect to the horizontal plane, the upper surface 1 is the upper circle of the frustum, and the lower surface 2 is the lower circle of the frustum. The connection line of the endpoints of the diameters on the same vertical plane between the upper circle and the lower circle of the frustum is the generatrix L of the frustum. In the embodiment of the present invention, the generatrix L of the transition part 3 is inclined, which can enable the sand mold 20 to generate a reaction force on the transition surface 31 that is inclined towards the central axis of the foam ceramic 10, so as to hold the foam ceramic 10 and make it not easy to fall. The included angle α between the generatrix L of the transition part 3 and the horizontal plane ranges from 25° to 65°. Within this included angle range, the lower surface 2 can obtain a larger area, thereby ensuring that the flow rate of the melt flowing in is within a reasonable range, and at the same time enabling the foam ceramic 10 to obtain a larger supporting force.
[0025] See Figure 1 and Figure 3 , a plurality of filter holes 4 with different shapes and sizes are provided on the foam ceramic 10. During use, the melt flows into the plurality of filter holes 4 from the upper surface 1 of the foam ceramic 10, passes through the filter holes 4, and finally flows into the casting mold from the lower surface 2. The plurality of filter holes 4 communicate with each other to connect the upper surface 1 and the lower surface 2 of the foam ceramic 10. The foam ceramic 10 is frustum-shaped with a wider upper part and a narrower lower part, and the side wall of the foam ceramic 10 is an inclined arc surface. The side wall of the foam ceramic 10 can fit with the inner wall of the conical sand mold 20. The inner wall of the sand mold 20 is in the shape of a funnel with a wider upper part and a narrower lower part, and its shape corresponds to the outer wall surface of the foam ceramic 10. Therefore, the inclined wall surface of the foam ceramic 10 can fit into the inner wall of the sand mold 20. This matching method enables the sand mold 20 to generate a reaction force on the foam ceramic 10 that is inclined in the direction of the central axis of the foam ceramic 10, which can make the foam ceramic 10 stable at its central axis position, improve the stability of the foam ceramic 10, and make it not easy to fall. The porosity of the foam ceramic 10 is 60% - 95%, which can provide good filtering performance and heat insulation performance.
[0026] The above are the preferred embodiments of the present invention. It should be noted that for those of ordinary skill in the art of this technology, without departing from the principle of the present invention, several improvements and refinements can be made, and these improvements and refinements are also regarded as the protection scope of the present invention.
Claims
1. A foam ceramic, characterized in that: It comprises an upper surface, a lower surface and a transition portion arranged between the upper surface and the lower surface, wherein the upper surface, the lower surface and the transition portion are all provided with a porous structure; The projection area of the upper surface on the horizontal plane is larger than the projection area of the lower surface on the horizontal plane. The side wall of the transition portion is provided with a transition surface, and the transition surface is an arc-shaped surface.
2. The foam ceramic according to claim 1, characterized in that The upper surface and the lower surface are both arranged horizontally, and the projection of the lower surface on the horizontal plane can fall within the projection of the upper surface on the horizontal plane.
3. The foam ceramic according to claim 1, characterized in that The upper surface and the lower surface are both circular in shape, and the centers of the upper surface and the lower surface are located on the same vertical line.
4. The foam ceramic according to claim 1, characterized in that The transition portion is in a truncated cone shape, and the transition surface is arranged to be inclined to a horizontal plane.
5. The foam ceramic according to claim 4, characterized in that: The included angle between the generatrix of the transition portion and the horizontal plane ranges from 25° to 65°.
6. The foam ceramic according to claim 1, characterized in that: A plurality of filter holes of different shapes and sizes are arranged in the upper surface, the lower surface and the transition portion, and the plurality of filter holes are interconnected so that the upper surface is connected with the lower surface.
7. The foam ceramic according to claim 1, characterized in that: The foam ceramic is in the shape of a truncated cone which is wide at the top and narrow at the bottom. The transition surface is an inclined arc surface, and the transition surface can fit with the inner wall of the conical sand mold.
8. The foam ceramic according to claim 1, characterized in that: The porosity of the foam ceramic is 60%-95%.