Automobile brake disc manufacturing device

Abstract

The utility model relates to an automobile brake disc preparation device which comprises a mold and a melt furnace. Wherein the mold comprises an upper mold body, a lower mold body and a female mold body which are coaxially arranged, after the mold is closed, the upper mold body and the lower mold body are enclosed in the female mold body to form a mold cavity, the mold cavity comprises a first part and a second part which are communicated with each other, the first part is matched with the annular disc body, the second part is matched with a disc cap to be formed, and a cooling device is arranged in the part, used for forming the disc cap, of the upper mold body; the melt furnace comprises a furnace body and a riser tube, one end of the riser tube is located in the furnace body, and the other end penetrates through the center of the lower die to communicate with the die cavity; and a ceramic reinforced aluminum matrix composite melt is filled in the furnace body. By means of the manufacturing device, the automobile brake disc which is high in density, intact in appearance, free of cracks and good in interface consistency can be manufactured.

Description

Technical Field

[0001] The utility model relates to the technical field of brake disc preparation, in particular to an automobile brake disc preparation device. Background Art

[0002] Lightweighting is one of the most effective means to achieve energy conservation and consumption reduction in automobiles and other transportation vehicles. Using high-performance light metal materials to replace steel materials in key moving parts such as the engines and brake discs of transportation equipment can not only reduce the vehicle's overall mass, lower the momentum of high-speed moving parts of transportation equipment, but also significantly improve the power performance of transportation equipment while reducing energy consumption.

[0003] Ceramic-reinforced aluminum matrix composites have low density, high specific strength and specific stiffness, high thermal conductivity, and excellent wear and corrosion resistance, and have broad application prospects in the field of lightweight structural parts. Specifically applied to brake discs, since the disc body needs to have properties such as high temperature resistance and wear resistance, and the disc cap needs to have relatively high mechanical properties, therefore, the disc body uses an aluminum matrix composite reinforced with a high volume fraction of ceramics, and the disc cap uses an aluminum matrix composite reinforced with a low volume fraction of ceramics to meet their respective performance requirements. However, when the above brake disc is prepared by the traditional powder metallurgy process, the two powder materials are likely to penetrate each other during the powder filling and pressing processes, resulting in an elliptical or even completely irregular interface between the disc body and the disc cap. In addition, considering that the formability of the aluminum matrix composite deteriorates due to the addition of the ceramic reinforcement phase in the ceramic-reinforced aluminum matrix composite, a simple green body, such as a ring-shaped or columnar green body, is usually pressed first, then sintered, and then forged and filled into the overall structure of the brake disc, such as a disc cap with a gooseneck structure, and finally machined into the final finished product. However, the flow of materials is not easy to control during the forging process of this process, and cracks are likely to appear on the outer side of the disc cap. Summary of the Utility Model

[0004] Based on this, it is necessary to provide an automobile brake disc preparation device that can ensure that even if the materials of the disc cap and the disc body are different, their interfaces remain consistent, and the prepared brake disc has good compactness and no cracks, meeting the braking requirements.

[0005] An automobile brake disc preparation device, the automobile brake disc includes an annular disc body and a disc cap, the disc cap includes an end portion, a side wall extending axially along the end portion, and a connecting portion extending radially along the side wall, the automobile brake disc preparation device includes a mold and a melt furnace:

[0006] The mold includes an upper mold, a lower mold, and a female mold that are coaxially arranged. After mold closing, the upper mold and the lower mold enclose the female mold to form a mold cavity. The mold cavity includes a first part and a second part that are in communication with each other. The first part is adapted to the annular disk body, and the second part is adapted to the disk cap to be formed. A cooling device is provided in the part of the upper mold for forming the disk cap.

[0007] The melt furnace includes a furnace body and a riser pipe. One end of the riser pipe is located inside the furnace body, and the other end passes through the center of the lower mold and communicates with the mold cavity. The furnace body is filled with a ceramic reinforced aluminum matrix composite melt.

[0008] In one embodiment, the diameter of the riser pipe at the connection with the mold cavity is 50 mm to 70 mm.

[0009] In one embodiment, the part of the upper mold for forming the end part has a thickness of 20 mm to 30 mm.

[0010] In one embodiment, the part of the upper mold for forming the side wall has a thickness of 15 mm to 25 mm.

[0011] In one embodiment, an air inlet and a pressure relief port are provided at the top of the furnace body.

[0012] In one embodiment, the cooling device includes a circulating cooling water pipe.

[0013] In one embodiment, the annular disk body includes an outer ring part and an inner ring part. The outer ring part is used for frictional braking with the brake pad, and the inner ring part is used for engaging with the disk cap. The thickness of the inner ring part is less than the thickness of the outer ring part.

[0014] In one embodiment, a plurality of axial through holes are evenly distributed along the circumferential direction of the inner ring part, and the aperture of each axial through hole is 8 mm to 16 mm.

[0015] In one embodiment, the height of the side wall of the disk cap is 10 mm to 35 mm.

[0016] In one embodiment, the height of the side wall of the disk cap is greater than 35 mm.

[0017] The above-mentioned automobile brake disc preparation device introduces the ceramic reinforced aluminum matrix composite melt into the mold cavity of the mold where the annular disk body has been placed by controlling the air flow pressure. Under the action of the cooling device, the melt gradually solidifies from the end in contact with the disk body to the end away from the disk body. By controlling the pressure holding time, on the one hand, it ensures that the melt fills the entire mold cavity and solidifies completely, and on the other hand, it can effectively reduce the shrinkage holes generated during the casting process and improve the density of the product.

[0018] In addition, since the annular disk body is already a finished part, its edge is relatively stable. After the melt contacts it and solidifies, it will not affect the edge, thus ensuring the consistency of the interface.

[0019] The automotive brake disc prepared by the above method has a perfect appearance without cracks and meets the braking performance required by the existing automotive brake disc. Description of the Drawings

[0020] Figure 1 It is a schematic diagram of the connection structure of a mold and a melt furnace in an embodiment. Detailed Embodiment

[0021] To facilitate the understanding of the present invention, the present invention will be described more comprehensively below, and preferred embodiments of the present invention are given. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the understanding of the disclosure of the present invention more thorough and comprehensive.

[0022] It should be noted that when an element is referred to as being "disposed" on another element, it can be directly on the other element or there may also be an intermediate element. When an element is considered to be "connected" to another element, it can be directly connected to the other element, or there may be an intermediate element at the same time.

[0023] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those of ordinary skill in the technical field to which the present invention belongs. The terms used in the description of the present invention in this specification are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more of the related listed items.

[0024] Please refer to Figure 1 , which is a schematic diagram of the connection structure of a mold and a melt furnace in an embodiment. Among them, the mold 10 includes an upper mold 12, a lower mold 14 and a female mold 16 arranged coaxially; after the mold is closed, the upper mold 12 and the lower mold 14 enclose the female mold 16 to form a mold cavity. The mold cavity includes a first part 102 and a second part 104 that communicate with each other, wherein the first part 102 is adapted to the annular disk body, and the second part 104 is adapted to the disk cap to be formed.

[0025] Furthermore, a cooling device 18 is provided in the part of the upper mold 12 for forming the disk cap. Further still, the cooling device 18 includes a circulating cooling water pipe.

[0026] In this embodiment, the disc cap includes an end portion, a side wall extending axially along the end portion, and a connecting portion extending radially along the side wall. The portion of the upper die 12 for forming the end portion has a thickness of 20 mm to 30 mm. The portion of the upper die 12 for forming the side wall has a thickness of 15 mm to 25 mm.

[0027] By providing a cooling device 18 in the portion of the upper die 12 for forming the disc cap, the temperature in the mold cavity can be gradually reduced.

[0028] Furthermore, the melt furnace 20 includes a furnace body 22 and a riser tube 24. One end of the riser tube 24 is located inside the furnace body 22, and the other end passes through the center of the lower die 14 and communicates with the mold cavity.

[0029] Furthermore, an air inlet 222 and a pressure relief port 224 are provided at the top of the furnace body 22. During casting, the pressure relief port 224 is closed, and the air flow is controlled to enter the furnace body 22 through the air inlet 222, and the compressed melt enters the mold cavity through the riser tube 24; after casting is completed, the air inlet 222 is closed, and the pressure relief port 224 is opened for pressure relief.

[0030] In this embodiment, the furnace body 22 contains a ceramic reinforced aluminum matrix composite melt at 700 °C to 740 °C. The ceramic reinforced aluminum matrix composite melt is composed of 10% to 20% ceramic reinforcing particles and the balance of aluminum alloy. Among them, the aluminum alloy is selected from at least one of the second series aluminum alloy, the fourth series aluminum alloy, and the sixth series aluminum alloy.

[0031] Selecting the ceramic reinforced aluminum matrix composite melt with the above special composition can, on the one hand, meet the performance requirements of the brake disc cap structure, and on the other hand, facilitate machining of the excess solidified melt, such as the solidified melt at the center hole position of the disc cap end portion.

[0032] In this embodiment, the diameter of the riser tube 24 at the connection with the mold cavity is 50 mm to 70 mm.

[0033] A method for preparing an automotive brake disc according to an embodiment includes the following steps S110 to S130:

[0034] S110. Provide an annular disc body.

[0035] The annular disc body includes an outer ring portion and an inner ring portion, and the thickness of the inner ring portion is less than that of the outer ring portion. Among them, the outer ring portion is used for frictional braking with the brake pad, and the inner ring portion is used for engaging with the disc cap.

[0036] It can be understood that the inner ring portion can be a continuous inner ring or an inner ring composed of a plurality of protrusions extending radially and evenly spaced along the circumference.

[0037] To meet the requirements of frictional braking, the annular disc body is prepared from 35% - 55% ceramic reinforcing particles and the balance aluminum alloy. The aluminum alloy is selected from at least one of the second series aluminum alloy, the fourth series aluminum alloy, and the sixth series aluminum alloy.

[0038] It should be noted that the annular disc body of the present application can be prepared by powder metallurgy process with the above materials, or by infiltration process, as long as it can meet the requirements of frictional braking.

[0039] Furthermore, a number of axial through - holes are evenly distributed along the circumferential direction of the inner ring part, and the aperture of each axial through - hole is 8mm - 16mm. It can be understood that if the inner ring part is composed of a plurality of protrusions that are evenly spaced along the circumferential direction and radially extend, the above - mentioned axial through - holes are correspondingly arranged on each protrusion.

[0040] By setting the axial through - holes, the subsequent ceramic - reinforced aluminum - matrix composite melt flows into these through - holes and solidifies, and the solidified melt completely wraps the inner ring part of the disc body, which can effectively improve the connection strength between the disc body and the disc cap.

[0041] S120. Provide the mold 10 and the melt furnace 20 as Figure 1 shown.

[0042] S130. Place the above - mentioned annular disc body in the first part 102 of the mold cavity, preheat it to 200°C - 250°C after closing the mold, start the cooling device 18, control the air flow pressure into the furnace body 22 to be 0.05MPa - 0.15MPa, compress the ceramic - reinforced aluminum - matrix composite melt to enter the mold cavity through the riser pipe, release the pressure after holding the pressure for 10s - 25s, cool, demold, and machine - process to obtain the automotive brake disc.

[0043] Among them, the air flow is an inert gas flow, such as argon, nitrogen, etc., to prevent the melt from being oxidized and affecting the combination with the disc body.

[0044] Placing the annular disc body in the first part of the mold cavity, preheating it to 200°C - 250°C after closing the mold, and then starting the cooling device while introducing the high - temperature melt can, on the one hand, effectively remove the water vapor adsorbed on the mold surface and avoid the generation of pores on the surface of the workpiece during casting, and on the other hand, avoid the high - temperature melt directly contacting the cooling disc body and the mold wall, resulting in cracks.

[0045] By controlling the air flow pressure to be 0.05MPa - 0.15MPa and the pressure - holding time to be 10s - 25s, it can not only ensure that the melt fills the entire mold cavity and solidifies completely, but also effectively reduce the shrinkage cavities generated during the casting process, improve the density of the product, so that it is only necessary to machine - process to remove the excess solidified melt after demolding later, without the need for forging densification.

[0046] Furthermore, the cooling temperature is below 100°C. Demolding after cooling can effectively avoid deformation caused by inconsistent thermal expansion coefficients between the disc body material and the disc cap material.

[0047] The above method can be used to prepare an automotive brake disc with a disc cap side wall height of 10 mm to 35 mm. Without forging densification, an automotive brake disc with high density, no cracks, and meeting the braking requirements can be obtained.

[0048] If the disc cap side wall height exceeds 35 mm, forging densification is required after demolding and before machining to further improve the density of the brake disc.

[0049] For the preparation method of the above automotive brake disc, by controlling the temperature of the melt to be 700°C to 740°C, the part of the upper mold 12 for forming the end is 20 mm to 30 mm thick, the part of the upper mold 12 for forming the side wall is 15 mm to 25 mm thick, then by controlling the diameter of the liquid riser 24 at the connection with the mold cavity to be 50 mm to 70 mm, and at the same time controlling the air flow pressure into the melt furnace 20 to be 0.05 MPa to 0.15 MPa, and the pressure holding time to be 10 s to 25 s, with all aspects cooperating, the melt can just fill the entire mold cavity and solidify completely, and shrinkage cavities generated during the casting process can be effectively reduced, improving the density of the product.

[0050] The following are specific examples.

[0051] Example 1

[0052] An automotive brake disc with a disc cap side wall height of 35 mm was prepared using the steps as in steps S110 to S130. The temperature of the melt was controlled to be 700°C, the part of the upper mold 12 for forming the end was 20 mm thick, the part of the upper mold 12 for forming the side wall was 15 mm thick, the diameter of the liquid riser 24 at the connection with the mold cavity was 50 mm, the air flow pressure into the melt furnace 20 was 0.05 MPa, and the pressure holding time was 10 s. An automotive brake disc with high density, good appearance, no cracks, and good interface consistency was obtained.

[0053] Comparative Example 1

[0054] Comparative Example 1 was basically the same as Example 1, except that the air flow pressure into the melt furnace 20 was 0.03 MPa. After demolding, there were micro-cracks at the connection position between the friction layer and the structural layer on one side of the back of the disc cap. The cracks could not be completely removed by machining, and the brake disc was unqualified.

[0055] Example 2

[0056] The automotive brake disc with a disc cap sidewall height of 30 mm is prepared by the steps such as steps S110 to S130. The temperature of the melt is controlled at 740 °C. The part of the upper die 12 for forming the end is 30 mm thick, and the part of the upper die 12 for forming the sidewall is 25 mm thick. The diameter of the liquid riser 24 at the connection with the mold cavity is 70 mm. The air flow pressure introduced into the melt furnace 20 is 0.15 MPa, and the pressure holding time is 25 s. An automotive brake disc with good appearance, no cracks, and good interface consistency can be obtained.

[0057] Comparative Example 2

[0058] Comparative Example 2 is basically the same as Example 2, except that the air flow pressure introduced into the melt furnace 20 is 0.03 MPa. After demolding, there are microcracks at the connection position between the friction layer and the structural layer on one side of the back of the disc cap. The cracks cannot be completely removed by machining, and the brake disc is unqualified.

[0059] Example 3

[0060] The automotive brake disc with a disc cap sidewall height of 45 mm is prepared by the steps such as steps S110 to S130. Forging densification is carried out before machining after demolding. The temperature of the melt is controlled at 720 °C. The part of the upper die 12 for forming the end is 25 mm thick, and the part of the upper die 12 for forming the sidewall is 20 mm thick. The diameter of the liquid riser 24 at the connection with the mold cavity is 60 mm. The air flow pressure introduced into the melt furnace 20 is 0.10 MPa, and the pressure holding time is 20 s. An automotive brake disc with good appearance, no cracks, and good interface consistency can be obtained.

[0061] Comparative Example 3

[0062] Comparative Example 3 is basically the same as Example 3, except that the forging step is omitted, and as a result, the brake disc fails the bench test.

[0063] The above-described embodiments only represent several implementation manners of the present utility model. The description is relatively specific and detailed, but it should not be construed as a limitation on the scope of the patent of the present utility model. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present utility model, several deformations and improvements can still be made, and these all belong to the protection scope of the present utility model. Therefore, the protection scope of the patent of the present utility model should be subject to the appended claims.

Claims

1. An automobile brake disc preparation device, the automobile brake disc comprising an annular disc body and a disc cap, the disc cap comprising an end portion, a side wall axially extending along the end portion, and a connecting portion radially extending along the side wall, characterized in that, The automobile brake disc manufacturing device includes a mold and a melt furnace; The mold includes an upper mold, a lower mold, and a female mold that are coaxially arranged. After the molds are closed, the upper mold and the lower mold enclose the female mold to form a mold cavity. The mold cavity includes a first part and a second part that are in communication with each other. The first part is adapted to the annular disc body, and the second part is adapted to the disc cap to be formed. A cooling device is provided in the part of the upper mold for forming the disc cap; The melt furnace includes a furnace body and a riser pipe. One end of the riser pipe is located inside the furnace body, and the other end passes through the center of the lower mold and communicates with the mold cavity; The furnace body is filled with a ceramic reinforced aluminum matrix composite melt.

2. The automotive brake disc preparation device according to claim 1, wherein The diameter of the riser pipe at the connection with the mold cavity is 50 mm to 70 mm.

3. The automobile brake disc preparation device according to claim 1, characterized in that, The part of the upper mold for forming the end is 20 mm to 30 mm thick.

4. The automobile brake disc preparation device according to claim 1, characterized in that The part of the upper mold for forming the side wall is 15 mm to 25 mm thick.

5. The automobile brake disc preparation device according to claim 1, wherein, An air inlet and a pressure relief port are provided at the top of the furnace body.

6. The automobile brake disc preparation device according to claim 1, characterized in that, The cooling device includes a circulating cooling water pipe.

7. The automobile brake disc preparation device according to any one of claims 1 to 6, characterized in that The annular disc body includes an outer ring part and an inner ring part. The outer ring part is used for frictional braking with the brake pad, and the inner ring part is used for joining with the disc cap. The thickness of the inner ring part is less than the thickness of the outer ring part.

8. The automobile brake disc preparation device according to claim 7, wherein, A plurality of axial through holes are evenly distributed along the circumferential direction of the inner ring part, and the aperture of each axial through hole is 8 mm to 16 mm.

9. The automotive brake disc manufacturing device according to any one of claims 1 to 6, characterized in that, The height of the side wall of the disc cap is 10 mm to 35 mm.

10. The automotive brake disc preparation device according to any one of claims 1 to 6, characterized in that, The height of the side wall of the disc cap is greater than 35 mm.

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