CN221087262U - Brake disc green compact forming die and forming press - Google Patents

Abstract

The application relates to a brake disc green forming die and a forming press, wherein the inner wall of a female die of the die comprises a first section extending along the axial direction, a second section extending outwards from the axial direction by 0.5-1.0 degrees, a third section extending outwards from the axial direction by 1.0-2.0 degrees and a fourth section extending outwards from the axial direction by 0-1.0 degrees, after the die is closed, at least part of a lower die is tightly matched with the first section, at least part of an upper die is in clearance fit with the fourth section, powder raw materials are molded in the die, so that abrasion of the female die caused by the powder raw materials can be avoided, the product percent of pass can be effectively improved, and the service life of the die is prolonged.

Description

Brake disc green compact forming die and forming press

Technical Field

The utility model relates to the technical field of brake discs, in particular to a brake disc green body forming die and a forming press.

Background

The ceramic particle reinforced aluminum matrix composite has low density, high specific strength and specific rigidity, high heat conductivity, excellent wear resistance and corrosion resistance, and wide application prospect in the field of lightweight structural members. In particular to a brake disc, the disc body is required to have high temperature resistance, wear resistance and other performances, and the disc cap is required to have relatively high mechanical properties, so the disc body is usually prepared from a high-volume-fraction ceramic reinforced aluminum-based composite material, and the disc cap is usually prepared from a low-volume-fraction ceramic reinforced aluminum-based composite material so as to meet respective performance requirements. However, when the brake disc is prepared by adopting a powder metallurgy process, in the compression molding process of a traditional die, the high-volume-fraction ceramic-reinforced aluminum-based composite material can wear a female die of the brake disc, and after the female die wears, a pressed green body can crack in the demolding process, so that the product percent of pass is reduced, and the service life of the die is shortened.

Disclosure of utility model

Based on the above, it is necessary to provide a brake disc green forming die in which powder material is molded to avoid abrasion to a female die, thereby improving the yield of products and prolonging the service life of the die.

The brake disc green body forming die comprises an upper die, a lower die and a female die which are coaxially arranged, wherein after die assembly, the upper die and the lower die are enclosed in the female die to form a closed die cavity, the inner wall of the female die comprises a first section extending along the axial direction, a second section extending outwards from the axial direction by 0.5 degrees to 1.0 degrees, a third section extending outwards from the axial direction by 1.0 degrees to 2.0 degrees and a fourth section extending outwards from the axial direction by 0 to 1.0 degrees, and the first section, the second section, the third section and the fourth section are sequentially connected; after the die is assembled, the lower die is at least partially matched with the first section in a close fit mode, and the upper die is at least partially matched with the fourth section in a clearance fit mode.

In one embodiment, the axial height of the second section is 35 mm-45 mm, the axial height of the third section is 35 mm-50 mm, and the axial height of the fourth section is 20 mm-30 mm.

In one embodiment, the lower die comprises a lower die inner punch and a lower die outer punch sleeved on the lower die inner punch, and after die assembly, the lower die outer punch is at least partially tightly matched with the first section.

In one embodiment, the upper die outer wall extends axially; the outer wall of the lower die outer punch extends along the axial direction.

In one embodiment, after die assembly, the single-side distance between the lower die outer punch and the first section is 0.06 mm-0.1 mm; the minimum unilateral distance between the upper die and the fourth section is 0.1 mm-0.15 mm.

In one embodiment, the upper die bottom surface includes a central concave surface and a peripheral elevated surface, the shape of the central concave surface is adapted to the top surface of the lower die inner punch, and the shape of the peripheral elevated surface is adapted to the top surface of the lower die outer punch.

In one embodiment, the height difference between the middle concave surface and the peripheral high surface is 1.5mm to 3mm.

In one embodiment, the die further comprises a core column coaxially arranged with the female die, and the upper die and the lower die are internally punched with axial through holes respectively for the core column to pass through.

In one embodiment, the female mold comprises a base layer and a wear layer, wherein the thickness of the wear layer is 0.02 mm-0.2 mm.

In addition, the application also provides a forming press, which comprises the brake disc green forming die.

The inner wall of the female die of the brake disc green forming die is provided with a first section extending along the axial direction, a second section extending outwards from the axial direction by 0.5 degrees to 1.0 degrees, a third section extending outwards from the axial direction by 1.0 degrees to 2.0 degrees and a fourth section extending outwards from the axial direction by 0 degrees to 1.0 degrees, wherein the enclosed area of the first section is used for limiting the lower die, the enclosed area of the fourth section is used for limiting the upper die, and the enclosed area of the second section and the third section is used for filling powder. After the die is assembled, the upper die is in clearance fit with the fourth section, the fourth section deviates from the axial direction and extends outwards for 0-1.0 degrees, friction between the upper die and the inner wall of the fourth section female die in the moving process can be prevented, and abrasion to the inner wall of the fourth section female die is avoided; the lower die is tightly matched with the first section, the second section deviates from the axial direction and extends outwards for 0.5-1.0 degrees, and powder raw materials can be prevented from leaking into the area enclosed by the inner wall of the first section female die, so that the lower die is prevented from wearing the inner wall of the first section female die in the moving process; thereby effectively prolonging the service life of the die.

Meanwhile, the first section extends along the axial direction, the second section deviates from the axial direction and extends outwards by 0.5-1.0 degrees, the third section deviates from the axial direction and extends outwards by 1.0-2.0 degrees, the fourth section deviates from the axial direction and extends outwards by 0-1.0 degrees, and a female die cavity structure with the inner diameter gradually becoming larger from bottom to top can be formed, so that cracking of a blank body in the demolding process is effectively avoided, and the qualification rate of products is improved.

Drawings

FIG. 1 is a schematic diagram of a brake disc green forming mold structure according to one embodiment;

fig. 2 is a schematic structural view of the inner wall of the female mold in fig. 1.

Detailed Description

The present utility model will be described more fully hereinafter in order to facilitate an understanding of the present utility model, and preferred embodiments of the present utility model are set forth. This utility model may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete.

It will be understood that when an element is referred to as being "disposed" on another element, it can be directly on the other element or intervening elements may also be present.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this utility model belongs. The terminology used herein in the description of the utility model is for the purpose of describing particular embodiments only and is not intended to be limiting of the utility model. The term "and/or" as used herein includes any and all combinations of one or more of the associated listed items.

Referring to fig. 1 and 2, a brake disc green forming mold 10 according to one embodiment includes an upper mold 12, a lower mold 14, and a female mold 16 coaxially disposed. After closing, the upper die 12 and the lower die 14 are enclosed in the female die 16 to form a closed cavity.

It will be appreciated that the shape of the closed mould cavity is adapted to the shape of the green brake disc, and that the powder charge for preparing the green brake disc is compacted in the mould cavity to give the green brake disc.

In the present application, the inner wall of the female mold 16 includes a first section 162 extending axially, a second section 164 extending 0.5 ° to 1.0 ° away from axially outward, a third section 166 extending 1.0 ° to 2.0 ° away from axially outward, and a fourth section 168 extending 0 ° to 1.0 ° away from axially outward. After clamping, the lower die 14 is at least partially mated with the first segment 162 and the upper die 12 is at least partially clearance mated with the fourth segment 168.

Wherein, the area enclosed by the first section 162 is used for limiting the lower die 14, the area enclosed by the fourth section 168 is used for limiting the upper die 12, and the area enclosed by the second section 164 and the third section 166 is used for filling powder raw materials.

It should be noted that, too large or too small deviation angle of the inner wall of any section of female die may cause uneven tensile stress or compressive stress on the blank during the demolding process, thereby causing cracking or deformation of the blank and reducing the qualification rate of the product.

Further, the axial height of the second section 164 is 35mm to 45mm, the axial height of the third section 166 is 35mm to 50mm, and the axial height of the fourth section 168 is 20mm to 30mm.

Further, the lower die 14 includes a lower die inner punch 142 and a lower die outer punch 144 sleeved on the lower die inner punch 142. After clamping, the lower outer die punch 144 is at least partially mated with the first segment 162.

Further, the outer wall of the upper die 12 extends in the axial direction, and the outer wall of the lower die outer punch 144 extends in the axial direction. After the die assembly, the minimum unilateral distance between the upper die 12 and the fourth segment 168 is 0.1 mm-0.15 mm. The single-sided distance between the lower die outer punch 144 and the first stage 162 is 0.1mm to 0.15mm.

When the fourth section 168 extends outwards by 0 ° from the axial direction, the fourth section 168 extends axially, and at this time, the outer wall of the upper die 12 is parallel to the fourth section 168, and the unilateral distance between the upper die 12 and the fourth section 168 is always consistent, so that the value can be taken in the range of 0.1mm to 0.15 mm; when the fourth segment 168 extends 0-1.0 ° outward from the axial direction, and does not include 0 °, a minimum value and a maximum value exist for the unilateral distance between the upper die 12 and the fourth segment 168, and the minimum value can be within the range of 0.1 mm-0.15 mm.

Further, the bottom surface of upper die 12 includes a central concave surface 122 and a peripheral raised surface 124, wherein the central concave surface 122 is shaped to fit the top surface of lower die inner punch 142 and the peripheral raised surface 124 is shaped to fit the top surface of lower die outer punch 144.

Further, the height difference between the intermediate recessed surface 122 and the peripheral elevated surface 124 is 1.5mm to 3mm. The intermediate concave surface 122 is adapted to engage the lower die inner punch 142 during powder filling of the outer ring to prevent powder leakage into the inner ring area during powder filling of the outer ring.

In this embodiment, the mould 10 further comprises a stem 18 arranged coaxially with the female mould 16. The upper die 12 is provided with an axial through hole 182 through which the stem 18 passes, and the lower die inner punch 144 is provided with an axial through hole 184 through which the stem 18 passes. The stem 18 is axially movable within the axial throughbore 182 and the axial throughbore 184.

It will be appreciated that the arrangement of the stem 18 is primarily intended for forming annular brake disc green bodies.

In order to further improve the hardness and the wear resistance of the inner wall of the female mold and prevent the female mold from being worn, in the present embodiment, the female mold comprises a base layer and a wear-resistant layer, wherein the wear-resistant layer is a layer formed by coating the base layer. The raw materials used for coating treatment are selected from one of chromium carbide, tungsten carbide, titanium carbide and vanadium carbide.

After treatment, the hardness of the inner wall of the female die is more than 60HRC, and the surface roughness is less than 0.5um.

Further, the thickness of the wear-resistant layer is 0.02 mm-0.2 mm. The excessive thickness of the wear-resistant layer can cause the inner diameter of the female die to be reduced, thereby affecting the size and shape of the blank body and reducing the qualification rate of the product; meanwhile, too thick wear-resisting layer can increase the stress between wear-resisting layer and matrix layer, lead to wear-resisting layer to drop or fracture easily, influence the life of mould. The abrasion-resistant layer is too thin to cause insufficient protection effect on the matrix layer, so that abrasion of powder raw materials on the inner wall of the female die cannot be effectively prevented, and the service life of the die is influenced; meanwhile, too thin wear-resistant layer can reduce hardness and wear resistance of the wear-resistant layer, and quality and performance of the product are affected.

In use, the brake disc green mold 10 described above is used to obtain a brake disc green by filling the areas enclosed by the second and third sections 164, 166 with the powder raw materials required for the brake disc green, and then closing the mold and pressing the mold.

Specifically, the method comprises the following steps S110 to S160:

S110, moving the lower die inner punch 142 to the top surface of the lower die inner punch is flush with the tail end of the fourth section 168;

S120, moving the lower die outer punch 144 to the top surface of the lower die outer punch is flush with the tail end of the first section 162;

S130, after powder raw materials required by the brake disc body green compact are filled in the area surrounded by the second section 164 and the third section 166, the upper die 12 is moved to the position that the peripheral high surface 124 of the upper die is flush with the top end of the fourth section 168, and meanwhile, the lower die outer punch 144 is upwardly pre-pressed to obtain a pre-pressed blank;

s140, the upper die 12 is moved out of the female die 16;

s150, moving the lower die inner punch 142 to a set height;

And S160, after filling powder raw materials required by the brake disc cap green body in the pre-blank enclosing area, the upper die 12 is downwards moved to the position where the peripheral high surface 124 is flush with the top end of the fourth section 168, and simultaneously, the lower die outer punch 144 and the lower die inner punch 142 are integrally upwards pressed and demoulded, so that the brake disc green body can be obtained.

It should be noted that, the end of the first segment 162 and the top end of the second segment 164 are the connection ends of the first segment 162 and the second segment 164, and then the end of the first segment 162 away from the end is the top end thereof; the end of the second section 164 and the top end of the third section 166 are the connecting ends of the second section 164 and the third section 166; the end of the third segment 166 and the top end of the fourth segment 168 are the connecting segments of the third segment 166 and the fourth segment 168, and the end of the fourth segment 168 remote from the top end thereof is the end thereof.

After the brake disc green forming die 10 is assembled, the upper die 12 is in clearance fit with the fourth section 168, the fourth section 168 deviates from the axial direction and extends outwards by 0-1.0 degrees, friction between the upper die 12 and the inner wall of the fourth section female die in the moving process can be prevented, and abrasion to the inner wall of the fourth section female die is avoided; the lower die 14 is tightly matched with the first section 162, and the second section 164 extends outwards for 0.5-1.0 degrees from the axial direction, so that powder raw materials can be prevented from leaking into the area enclosed by the inner wall of the first section female die, and abrasion of the inner wall of the first section female die caused by the lower die 14 in the moving process is avoided; thereby effectively prolonging the service life of the die.

Meanwhile, the first section 162 extends along the axial direction, the second section 164 extends outwards for 0.5-1.0 degrees from the axial direction, the third section 166 extends outwards for 1.0-2.0 degrees from the axial direction, and the fourth section 168 extends outwards for 0-1.0 degrees from the axial direction, so that a female die cavity structure with the inner diameter gradually increased from bottom to top can be formed, cracking of a blank body in the demolding process is effectively avoided, and the qualification rate of products is improved.

The foregoing examples illustrate only a few embodiments of the utility model and are described in detail herein without thereby limiting the scope of the utility model. It should be noted that it will be apparent to those skilled in the art that several variations and modifications can be made without departing from the spirit of the utility model, which are all within the scope of the utility model. Accordingly, the scope of protection of the present utility model is to be determined by the appended claims.

Claims (10)

1. The brake disc green body forming die comprises an upper die, a lower die and a female die which are coaxially arranged, wherein after die assembly, the upper die and the lower die are enclosed in the female die to form a closed die cavity, and the brake disc green body forming die is characterized in that the inner wall of the female die comprises a first section extending along an axial direction, a second section extending outwards from the axial direction by 0.5 degrees to 1.0 degrees, a third section extending outwards from the axial direction by 1.0 degrees to 2.0 degrees and a fourth section extending outwards from the axial direction by 0 to 1.0 degrees, and the first section, the second section, the third section and the fourth section are sequentially connected; after the die is assembled, the lower die is at least partially matched with the first section in a close fit mode, and the upper die is at least partially matched with the fourth section in a clearance fit mode.

2. The brake disc green forming die of claim 1, wherein the axial height of the second section is 35mm to 45mm, the axial height of the third section is 35mm to 50mm, and the axial height of the fourth section is 20mm to 30mm.

3. The brake disc green body forming die of claim 1 or 2, wherein the lower die comprises a lower die inner punch and a lower die outer punch sleeved on the lower die inner punch, and after die clamping, the lower die outer punch is at least partially in close fit with the first section.

4. A brake disc green forming die according to claim 3, wherein the upper die outer wall extends in an axial direction; the outer wall of the lower die outer punch extends along the axial direction.

5. The brake disc green compact forming die of claim 4, wherein after clamping, the single side distance between the lower die outer punch and the first section is 0.06mm to 0.1mm; the minimum unilateral distance between the upper die and the fourth section is 0.1 mm-0.15 mm.

6. A brake disc green forming die as claimed in claim 3 wherein the upper die bottom surface includes a central concave surface shaped to fit the top surface of the lower die inner punch and a peripheral raised surface shaped to fit the top surface of the lower die outer punch.

7. The brake disc green forming die according to claim 6, wherein a height difference between the intermediate recessed surface and the peripheral elevated surface is 1.5mm to 3mm.

8. A brake disc green compact forming die as claimed in claim 3, further comprising a stem coaxially disposed with the female die, the upper and lower dies being internally punched with respective axial through holes through which the stem passes.

9. The brake disc green forming mold according to claim 1, wherein the female mold comprises a base layer and a wear layer, and the wear layer has a thickness of 0.02mm to 0.2mm.

10. A forming press comprising a brake disc green forming die according to any one of claims 1 to 9.