A powder metallurgy brake disc production process

Abstract

The present invention relates to the field of powder metallurgy technology, specifically to a powder metallurgy brake disc and a production process thereof, including a powder metallurgy brake disc, wherein the powder metallurgy brake disc comprises a disc body one, a disc body two and an assembly seat, a heat dissipation ring groove is provided between the disc body one and the assembly seat, and heat discharge grooves and heat dissipation columns are evenly distributed between the disc body one and the disc body two. The beneficial effect is: by changing the traditional powder metallurgy production process for preparing brake discs, first, the powder is added with auxiliary components such as lubricants, binders and sintering aids, and is evenly mixed to prepare particles with a size between 50 microns and 100 microns, and then pressed. This can not only improve the powder fluidity, formability and sintering performance, but also cooperate with special molds for upper and lower molds, so that the disc body one, the disc body two and the assembly seat can be pressed and formed as a whole, and then sintered and post-processed, thereby improving the strength of the brake disc while also improving the production efficiency of the brake disc.

Description

Technical Field

[0001] The invention belongs to the technical field of powder metallurgy, and in particular relates to a production process of a powder metallurgy brake disc. Background Art

[0002] Powder metallurgy brake discs are high-performance brake components manufactured using a powder metallurgy process and are widely used in vehicles such as automobiles, motorcycles, and trains, as well as in industrial machinery. These brake discs offer excellent wear resistance, high-temperature resistance, and braking performance, effectively enhancing vehicle safety and reliability. Prior art manufacturing processes for powder metallurgy brake discs typically involve cold-pressing metal powders, followed by high-temperature firing, and finally surface treatment. However, the resulting discs are semi-finished products that require subsequent assembly with heat dissipation components or cutting and drilling to create heat dissipation slots or holes. This makes subsequent processing complex and difficult.

[0003] The existing Chinese patent document with publication number CN113983090A proposes a powder metallurgy brake disc, which proposes that the brake disc body includes a first brake disc and a second brake disc, a mounting surface is provided at the center of the first brake disc, a center hole is provided in the middle of the mounting surface, the mounting surface is connected to the first brake disc, and there is a small hole between the mounting surface and the first brake disc. A hollow is opened at the center of the first brake disc, the outer side of the first brake disc is the first brake surface, and a heat dissipation hole is provided at a position corresponding to the hollow on the first brake surface. Multiple groups of copper tubes are provided through the edge circumference of the first brake surface, and multiple connecting blocks are welded in a ring shape on the inner side of the first brake surface. The second brake disc is welded on the other side of the connecting block. The center position of the second brake disc is a small hole to improve the heat dissipation performance of the brake disc, but dividing the brake disc into the first brake disc and the second brake disc and then welding them will reduce the overall strength of the brake disc.

[0004] Therefore, the present invention proposes a powder metallurgy brake disc production process to solve the problem in the prior art that dividing the brake disc into a first brake disc and a second brake disc and then welding them will reduce the overall strength of the brake disc. The production process of the traditional powder metallurgy brake disc is improved by adding a certain proportion of lubricant and binder to improve the powder fluidity, formability and sintering properties, and the brake disc is sintered into an integral part with a mold of a special shape, thereby improving the strength of the brake disc while also improving the production efficiency of the brake disc. Summary of the Invention

[0005] In view of the shortcomings of the prior art, the present invention aims to provide a powder metallurgy brake disc production process to solve the problems raised in the above background technology.

[0006] To achieve the above-mentioned objectives, the present invention provides the following technical solutions: a powder metallurgy brake disc, comprising a powder metallurgy brake disc, the powder metallurgy brake disc comprising a disc body one, a disc body two and an assembly seat, a heat dissipation ring groove is provided between the disc body one and the assembly seat, heat discharge grooves and heat dissipation columns are evenly distributed between the disc body one and the disc body two, the heat discharge grooves and the heat dissipation columns are spaced apart, a reinforcement ring is provided on the side of the assembly seat close to the disc body one, and arc grooves are provided on both sides of the heat dissipation columns.

[0007] The present invention also proposes a powder metallurgy brake disc production process, comprising the following steps: Step 1: uniformly mixing various metal powders and additives in proportion, granulating the mixed powders by a spray drying method to prepare a granular material, the granular material having a size between 50 microns and 100 microns; the specific proportions of various powders are: 4% graphite, 6% copper powder, 3% nickel powder, 3% molybdenum powder, 2% tungsten powder, 0.5% zinc stearate, 0.3% polyvinyl alcohol, 0.2% phenolic resin, 1% sintering aid, and the rest is iron; Step 2: designing a special mold for the brake disc according to the required size and shape of the brake disc, loading the prepared mixed particles into the mold, and cold pressing under high pressure to obtain a preliminary shape of the brake disc blank, the pressure is 800 MPa, and the pressing time is 20 seconds; Step 3: performing a sintering treatment, pre-burning the cold-pressed blank at a lower temperature to remove residual organic matter and preliminarily Densification, the pre-sintering temperature is set between 300°C and 600°C, and the pre-sintering time is 3 hours. The pre-sintered green body should be naturally cooled to below 100°C at room temperature, and then the pre-sintered green body is finally sintered in a high-temperature furnace to allow diffusion and bonding between the powder particles to form a dense metal matrix. The final sintering temperature is usually between 1100°C and 1300°C, and the sintering time is 1.5 hours. Finally, the metal matrix is ​​taken out and naturally cooled to 850°C to 950°C at room temperature; Step 4: Post-treatment, first quenching and then tempering heat treatment process, the quenching temperature is 1200°C to 1300°C, after quenching for 5 minutes, quickly immersed in oil medium and quickly cooled to room temperature, and then tempered, the tempering temperature is 350°C to 500°C, and naturally cooled to room temperature after keeping warm for 1 hour; Finally, the brake disc is cleaned and fine-ground according to production requirements to ensure dimensional accuracy and surface finish.

[0008] Preferably, the brake disc special mold in step 2 includes an upper mold and a lower mold, the lower surface of the upper mold is fixedly installed with a guide column, the upper surface of the lower mold is provided with a guide hole adapted to the guide column, the middle part of the lower surface of the upper mold is fixedly installed with a first sealing platform, the middle part of the lower surface of the first sealing platform is fixedly installed with a second sealing platform, the middle part of the lower surface of the second sealing platform is fixedly installed with a forming tube, the interior of the forming tube is fixedly installed with a forming column, and the depth of the forming tube is adapted to the depth of the heat dissipation ring groove.

[0009] Preferably, an upper sealing ring is fixedly installed above the inner wall of the lower mold, a mold base is fixedly installed at the bottom of the inner wall of the lower mold, a sealing bottom plate is fixedly installed below the mold base by bolts, and a bottom sealing ring is fixedly installed on the upper surface of the mold base.

[0010] Preferably, a combined molded single-cavity plate is evenly distributed between the mold base and the upper sealing ring, a spacer block is fixedly installed on the inner middle part of the combined molded single-cavity plate, and demolding circular protrusions adapted to the arc groove are provided on both sides of the spacer block. The position of the spacer block is adapted to the position of the heat dissipation column, a sliding block is fixedly installed on the outer surface of the combined molded single-cavity plate, the inner side wall of the lower mold is provided with a limiting strip adapted to the sliding block, and the side wall of the combined molded single-cavity plate is provided with a square hole adapted to the limiting strip.

[0011] Preferably, a side sealing rubber block is fixedly installed on one side wall of the combined molded single-cavity plate, a card slot adapted to the side sealing rubber block is provided on the other side wall of the combined molded single-cavity plate, a bottom limiting elastic block is movably installed on the bottom of the combined molded single-cavity plate, and the upper surface of the bottom sealing ring is provided with a card slot adapted to the bottom limiting elastic block.

[0012] Preferably, a molding cavity is provided on the inner side of the bottom sealing ring, an adjustment disk is rotatably installed between the inner wall of the lower mold and the outer wall of the bottom sealing ring, a gear ring is fixedly installed on the outer surface of the adjustment disk, and a gear is provided on one side of the upper surface of the mold base, and the side surface of the gear is engaged with the side surface of the gear ring.

[0013] Preferably, a locking sealing ring is clamped and installed above the upper sealing ring, and a locking block adapted to the sliding block is fixedly installed on the lower surface of the locking sealing ring.

[0014] Preferably, a demoulding push block is provided on the bottom inner wall of the mold base, a fixing ring is fixedly installed below the demoulding push block, a wedge block 1 is fixedly installed on the lower surface of the fixing ring, and a wedge block 2 is provided on one side of the wedge block 1.

[0015] Preferably, a threaded rod is rotatably installed on one side surface of the wedge block 2, the outer surface of the threaded rod is threadedly connected to the side wall of the mold base, the upper surface of the sealing bottom plate is provided with a limiting slide groove adapted to the wedge block 2, and a reset telescopic spring sleeve rod is fixedly installed between the upper surface of the fixing ring and the top of the inner surface of the mold base.

[0016] Compared with the prior art, the present invention has the following beneficial effects:

[0017] By changing the traditional powder metallurgy production process for preparing brake discs, the powder is first added with auxiliary ingredients such as lubricants, binders and sintering aids, and evenly mixed to prepare particles with a size between 50 microns and 100 microns, and then pressed. This not only improves the powder fluidity, formability and sintering performance, but also, with the help of special molds for the upper and lower molds, the disc body one, disc body two, and assembly seat can be pressed into one piece and then sintered and post-processed. This improves the strength of the brake disc while also improving the production efficiency of the brake disc, solving the problem in the prior art that the brake disc is divided into a first brake disc and a second brake disc and then welded, which reduces the overall strength of the brake disc. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 This is a schematic diagram of the overall top view of the powder metallurgy brake disc of the present invention;

[0019] Figure 2 This is a schematic diagram of the overall structure of the powder metallurgy brake disc of the present invention when viewed from above;

[0020] Figure 3 This is a schematic diagram of the overall cross-sectional structure of the powder metallurgy brake disc of the present invention;

[0021] Figure 4 This is a schematic diagram of the exploded structure of the powder metallurgy brake disc of the present invention;

[0022] Figure 5 Schematic diagram of the overall structure of the upper mold and the lower mold of the present invention;

[0023] Figure 6 This is a schematic diagram of the overall structure of the upper mold and the lower mold of the present invention when viewed from above;

[0024] Figure 7 This is a schematic diagram of the overall top view of the lower mold of the present invention;

[0025] Figure 8 This is a schematic diagram of the installation structure of the locking sealing ring of the present invention;

[0026] Figure 9 This is a schematic diagram of the structure of the combined molded single-cavity plate after dispersion of the present invention;

[0027] Figure 10 This is a schematic diagram showing the structure of the combined molded single-cavity plate of the present invention in a comparative manner between dispersed and aggregated states;

[0028] Figure 11 This is a schematic diagram of the internal structure of the mold base of the present invention when viewed from above;

[0029] Figure 12 This is a schematic diagram of the combined molding single-cavity plate structure of the present invention;

[0030] Figure 13Schematic diagram of the cross-sectional structure of the upper mold and the lower mold in the pressed state of the present invention;

[0031] Figure 14 This is a schematic diagram of the powder metallurgy brake disc production process of the present invention.

[0032] Figure: 1, powder metallurgy brake disc; 11, disc body 1; 12, disc body 2; 13, assembly seat; 2, heat dissipation ring groove; 21, heat dissipation groove; 22, heat dissipation column; 221, arc groove; 3, reinforcement ring; 4, upper mold; 41, first sealing platform; 42, second sealing platform; 43, forming tube; 431, forming column; 5, lower mold; 51, mold base; 511, sealing bottom plate; 512, bottom sealing ring; 52, upper sealing ring; 53, Locking sealing ring; 531, locking block; 54, combined molding single cavity plate; 541, spacer block; 5411, demoulding circular protrusion; 542, sliding block; 543, side sealing rubber block; 544, bottom limiting elastic block; 55, molding cavity; 56, demoulding push block; 561, fixing ring; 562, wedge block 1; 563, wedge block 2; 564, threaded rod; 565, reset telescopic spring sleeve rod; 57, adjusting plate; 571, gear ring; 572, gear. DETAILED DESCRIPTION

[0033] In order to clearly and completely describe the objectives and technical solutions of the present invention and make its advantages more clearly understood, the embodiments of the present invention are further described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are only part of the embodiments of the present invention, not all of them, and are only used to explain the embodiments of the present invention, not to limit the embodiments of the present invention. All other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0034] For example 1, please refer to Figures 1 to 14The present invention provides a technical solution: a powder metallurgy brake disc, comprising a powder metallurgy brake disc 1, the powder metallurgy brake disc 1 comprising a disc body 11, a disc body 2 12 and an assembly seat 13, a heat dissipation ring groove 2 is provided between the disc body 11 and the assembly seat 13, heat discharge grooves 21 and heat dissipation columns 22 are evenly distributed between the disc body 11 and the disc body 2 12, the heat discharge grooves 21 and the heat dissipation columns 22 are spaced apart, a reinforcement ring 3 is provided on the side of the assembly seat 13 close to the disc body 11, and arc grooves 221 are provided on both sides of the heat dissipation columns 22; in this embodiment, the disc body 11, the disc body 2 12 and the assembly seat 13 are an integrated brake disc, compared with the traditional brake disc, the disc body 11 and the disc body 2 12 are connected by bolts, and the integrated design reduces the disc body 11, the disc body 2 1 2, reduces the risk caused by loose bolts or connection failure, makes the overall structure stronger, can better withstand high loads and impact forces, and improves the stability and safety of the vehicle during driving. The design of the heat dissipation ring groove 2 increases the heat dissipation area, so that more heat can be dissipated through surface conduction and radiation. The ring groove structure can guide the air to flow along a specific path, accelerating the dissipation of heat, especially when driving at high speeds. The airflow through the ring groove can take away more heat, and the heat is dissipated in time when the brake disc rubs to avoid local heat accumulation. The heat dissipation column 22 not only serves to tightly connect the disc body 11 and the disc body 2 12 into one, but is also evenly distributed between the disc body 11 and the disc body 2 12. The heat dissipation column 22 separates the heat discharge groove 21. Further expanding the heat dissipation area ensures unimpeded air circulation and improves heat dissipation efficiency. The heat discharge groove 21 not only provides an additional heat dissipation path, but also optimizes the air exchange between the inside and outside of the brake disc, promotes the rapid dissipation of heat so that the heat can be more evenly distributed in the entire structure, avoiding local overheating. The arc groove 221 not only increases and optimizes the thermal conductivity of the heat dissipation column 22, but also facilitates demoulding. The cross-section of the assembly seat 13 is trapezoidal.

[0035] For example 2, please refer to Figures 1 to 14On the basis of Example 1, this embodiment further proposes a powder metallurgy brake disc production process, comprising the following steps: Step 1: uniformly mixing various metal powders and additives in proportion, granulating the mixed powders by a spray drying method to prepare a granular material, wherein the granular material has a size between 50 microns and 100 microns; the specific proportions of the various powders are: 4% graphite, 6% copper powder, 3% nickel powder, 3% molybdenum powder, 2% tungsten powder, 0.5% zinc stearate, 0.3% polyvinyl alcohol, 0.2% phenolic resin, 1% sintering aid, and the remainder is iron; Step 2: designing a special brake disc mold according to the required size and shape of the brake disc, loading the prepared mixed particles into the mold, and cold pressing under high pressure to obtain a preliminary shape of the brake disc blank, the pressure being 800 MPa, pressing time is 20 seconds; Step 3: Sintering treatment, pre-sintering the cold pressed green body at a relatively low temperature to remove residual organic matter and achieve preliminary densification, the pre-sintering temperature is set between 300 ° C and 600 ° C, the pre-sintering time is 3 hours, the pre-sintered green body should be naturally cooled to below 100 ° C at room temperature, and then the pre-sintered green body is finally sintered in a high-temperature furnace to allow diffusion bonding between the powder particles to form a dense metal matrix, the final sintering temperature is usually between 1100 ° C and 1300 ° C, and the sintering time is 1.5 hours, and finally take out the metal matrix and naturally cool it to 850°C to 950°C at room temperature; Step 4: Post-treatment, first quenching and then tempering heat treatment process, the quenching temperature is 1200°C to 1300°C, after quenching for 5 minutes, quickly immerse in oil medium and quickly cool to room temperature, then temper, the tempering temperature is 350°C to 500°C, keep warm for 1 hour and naturally cool to room temperature; finally, according to production requirements, the brake disc is cleaned and finely ground to ensure dimensional accuracy and surface finish; in this embodiment, compared with the traditional raw material ratio for the preparation of powder brake discs, the powder brake disc production process proposed in this embodiment firstly mixes the powder evenly to prepare it into particles with a size of 5 Particles between 0 microns and 100 microns are then pressed, which not only improves the powder fluidity, formability and sintering properties, but also adds auxiliary ingredients such as lubricants, binders and sintering aids. Particles between 50 microns and 100 microns are in a relatively ideal range. They are neither too fine to agglomerate nor too large to cause uneven filling. Within this particle size range, the friction between particles is moderate, reducing the possibility of mutual adhesion, allowing the powder to flow more smoothly. The particle distribution can be controlled for uniform filling, which helps to achieve more uniform mold filling, reduce local density differences, thereby improving the dimensional accuracy and shape integrity of the final product and facilitating cold pressing. Adding lubricants can reduce the coefficient of friction. Graphite and zinc stearate, for example, can form a thin protective film on the particle surface, reducing the inter-particle friction coefficient and further improving powder fluidity. They can also effectively prevent powder from adhering to the mold's inner wall, ensuring smooth demolding. Binders can improve inter-particle bonding. Polyvinyl alcohol (PVA) and phenolic resins, for example, can provide temporary adhesion between powder particles, enhancing the powder's integrity during the pressing process, preventing loosening or delamination and increasing green body strength. After pressing, the binder-containing green body has higher mechanical strength, facilitating subsequent handling and minimizing the risk of damage. Sintering aids, such as magnesium oxide and aluminum oxide, can lower sintering temperatures by promoting liquid phase formation or altering grain boundary behavior, reducing energy consumption and shortening production cycles. They can also promote densification. Glass powder and boric acid, for example, can promote contact and bonding between powder particles, increasing the material's density and, in turn, enhancing the mechanical properties of the finished product.

[0036] For example three, please refer to Figures 1 to 14On the basis of the second embodiment, this embodiment further proposes that the brake disc special mold in step 2 includes an upper mold 4 and a lower mold 5. The lower surface of the upper mold 4 is fixedly installed with a guide column, and the upper surface of the lower mold 5 is provided with a guide hole adapted to the guide column. The middle part of the lower surface of the upper mold 4 is fixedly installed with a first sealing platform 41, the middle part of the lower surface of the first sealing platform 41 is fixedly installed with a second sealing platform 42, and the middle part of the lower surface of the second sealing platform 42 is fixedly installed with a forming tube 43. The interior of the forming tube 43 is fixedly installed with a forming column 431. The depth of the forming tube 43 is the same as that of the heat dissipation ring groove 2. Depth adaptation, an upper sealing ring 52 is fixedly installed on the upper inner wall of the lower mold 5, a mold base 51 is fixedly installed on the bottom of the inner wall of the lower mold 5, a sealing bottom plate 511 is fixedly installed below the mold base 51 by bolts, a bottom sealing ring 512 is fixedly installed on the upper surface of the mold base 51, and a combined molding single cavity plate 54 is evenly distributed between the mold base 51 and the upper sealing ring 52. A spacer block 541 is fixedly installed on the inner middle part of the combined molding single cavity plate 54, and demoulding circular protrusions 5411 that are adapted to the arc groove 221 are provided on both sides of the spacer block 541. The position is adapted to the position of the heat dissipation column 22, the outer surface of the combined single-cavity plate 54 is fixedly installed with a sliding block 542, the inner side wall of the lower mold 5 is provided with a limiting strip adapted to the sliding block 542, the side wall of the combined single-cavity plate 54 is provided with a square hole adapted to the limiting strip, one side wall of the combined single-cavity plate 54 is fixedly installed with a side sealing rubber block 543, the other side wall of the combined single-cavity plate 54 is provided with a card slot adapted to the side sealing rubber block 543, the bottom of the combined single-cavity plate 54 is movably installed with a bottom limiting elastic block 544, and the upper surface of the bottom sealing ring 512 is provided with a There is a card slot adapted to the bottom limiting elastic block 544, a molding cavity 55 is provided on the inner side of the bottom sealing ring 512, an adjusting disk 57 is rotatably installed between the inner side wall of the lower mold 5 and the outer side wall of the bottom sealing ring 512, a gear ring 571 is fixedly installed on the outer surface of the adjusting disk 57, a gear 572 is provided on one side of the upper surface of the mold base 51, the side surface of the gear 572 and the side surface of the gear ring 571 are meshed with each other, a locking sealing ring 53 is clamped and installed above the upper sealing ring 52, and a locking block 531 adapted to the sliding block 542 is fixedly installed on the lower surface of the locking sealing ring 53;In this embodiment, the upper mold 4 and the lower mold 5 form a complete brake disc special mold. The rotating gear 572 can drive the gear ring 571 to rotate, and then drive the adjusting disk 57 to rotate a certain angle, so that the sliding block 542 moves synchronously inward under the cooperation of the limiting bar until the bottom limiting elastic block 544 pops out and is stuck in the groove on the outside of the bottom sealing ring 512. At this time, the side sealing rubber block 543 is clamped in sequence to make the combined single-cavity plates 54 bite each other to form a sealing ring, and then the locking sealing ring 53 is clamped above the upper sealing ring 52, and the locking block 531 is clamped in turn into the inner inclined surface of the sliding block 542 to lock the sealing ring formed by the mutual bite of the combined single-cavity plates 54, and then the mixed particles prepared in step 1 are evenly filled into the molding cavity 55 and the combined single-cavity plate The internal space of the sealing ring formed by 54 ensures that the spacer block 541 is completely covered. Finally, the upper mold 4 and the lower mold 5 are stamped and closed. At this time, the particles are squeezed into the internal space of the sealing ring formed by the molding cavity 55 and the combined molded single-cavity plate 54, flowing and extruding together. After the upper mold 4 is removed, the heat dissipation ring groove 2 is formed at the location of the molding tube 43. The gear 572 is then rotated in the opposite direction to rotate the adjustment disk 57 in the opposite direction. At this time, the spacer block 541 is withdrawn, and the location of the spacer block 541 forms a heat dissipation groove 21. The demolding circular protrusion 5411 shapes the arc groove 221, also facilitating demolding. Through the design of the upper mold 4 and the lower mold 5, the disc body 11, the disc body 2 12, and the assembly seat 13 can be pressed and formed as a whole, improving the strength of the brake disc while also improving the production efficiency of the brake disc.

[0037] For example 4, please refer to Figures 1 to 14 On the basis of the third embodiment, the present embodiment further proposes that a demoulding push block 56 is provided on the bottom inner wall of the mold base 51, a fixing ring 561 is fixedly installed below the demoulding push block 56, a wedge block 1 562 is fixedly installed on the lower surface of the fixing ring 561, a wedge block 2 563 is provided on one side of the wedge block 1 562, a threaded rod 564 is rotatably installed on one side surface of the wedge block 2 563, the outer surface of the threaded rod 564 is threadedly connected to the side wall of the mold base 51, and the upper surface of the sealing bottom plate 511 is provided with a wedge block 2 563. The mold base 51 is equipped with a limiting groove, and a reset telescopic spring sleeve rod 565 is fixedly installed between the upper surface of the fixing ring 561 and the top of the inner surface of the mold base 51; in this embodiment, the threaded rod 564 can be rotated to make the wedge block 2 563 slide in cooperation with the limiting groove on the upper surface of the sealing bottom plate 511, and the wedge block 2 563 lifts the wedge block 1 562. At this time, the fixing ring 561 is lifted as a whole, so that the demoulding push block 56 is lifted, which facilitates the demoulding of the powder metallurgy brake disc 1 from the bottom as a whole, thereby further improving the production efficiency of the brake disc.

[0038] While embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions, and variations may be made to these embodiments without departing from the principles and spirit of the invention, and that the scope of the invention is defined by the appended claims and their equivalents.

Claims

1. A process for producing a powder metallurgy brake disc, comprising a powder metallurgy brake disc (1), wherein the powder metallurgy brake disc (1) comprises a disc body (11), a disc body (12) and an assembly seat (13), a heat dissipation ring groove (2) is provided between the disc body (11) and the assembly seat (13), heat discharge grooves (21) and heat dissipation columns (22) are evenly distributed between the disc body (11) and the disc body (12), the heat discharge grooves (21) and the heat dissipation columns (22) are spaced apart, a reinforcement ring (3) is provided on one side of the assembly seat (13) close to the disc body (11), and arc grooves (221) are provided on both sides of the heat dissipation columns (22), characterized in that: The method comprises the following steps: Step 1: uniformly mixing various metal powders and additives in proportion, and granulating the mixed powders by a spray drying method to prepare a granular material, wherein the granular material has a size between 50 microns and 100 microns; the specific proportions of the various powders are: 4% graphite, 6% copper powder, 3% nickel powder, 3% molybdenum powder, 2% tungsten powder, 0.5% zinc stearate, 0.3% polyvinyl alcohol, 0.2% phenolic resin, 1% sintering aid, and the remainder iron; Step 2: Design a special brake disc mold according to the required brake disc size and shape, load the prepared mixed particles into the mold, and perform cold pressing under high pressure to obtain a preliminary shape of the brake disc blank. The pressure is 800 MPa and the pressing time is 20 seconds. Step 3: Sintering treatment, pre-sintering the cold pressed green body at a lower temperature to remove residual organic matter and achieve preliminary densification, the pre-sintering temperature is set between 300°C and 600°C, the pre-sintering time is 3 hours, the pre-sintered green body should be naturally cooled to below 100°C at room temperature, and then the pre-sintered green body is finally sintered in a high-temperature furnace to allow diffusion and bonding between the powder particles to form a dense metal matrix, the final sintering temperature is usually between 1100°C and 1300°C, the sintering time is 1.5 hours, and finally the metal matrix is ​​taken out and naturally cooled to 850°C to 950°C at room temperature; Step 4: Post-processing: first quenching and then tempering heat treatment process, the quenching temperature is 1200°C to 1300°C, after quenching for 5 minutes, quickly immersed in oil medium and quickly cooled to room temperature, then tempered, the tempering temperature is 350°C to 500°C, kept at this temperature for 1 hour and then naturally cooled to room temperature; finally, the brake disc is cleaned and finely ground according to production requirements to ensure dimensional accuracy and surface finish; The brake disc special mold of step 2 comprises an upper mold (4) and a lower mold (5), the lower surface of the upper mold (4) is fixedly mounted with a guide column, the upper surface of the lower mold (5) is provided with a guide hole adapted to the guide column, an upper sealing ring (52) is fixedly mounted above the inner wall of the lower mold (5), a mold base (51) is fixedly mounted at the bottom of the inner wall of the lower mold (5), a sealing bottom plate (511) is fixedly mounted below the mold base (51) by bolts, a bottom sealing ring (512) is fixedly mounted on the upper surface of the mold base (51), a combined molded single cavity plate (54) is evenly distributed between the mold base (51) and the upper sealing ring (52), a spacer block (541) is fixedly mounted on the inner middle of the combined molded single cavity plate (54), and two sides of the spacer block (541) are provided with a sealing bottom plate (511) aligned with the arc groove ( 221), the position of the spacer block (541) is adapted to the position of the heat dissipation column (22), the outer surface of the combined molded single-cavity plate (54) is fixedly installed with a sliding block (542), the inner side wall of the lower mold (5) is provided with a limiting strip adapted to the sliding block (542), the side wall of the combined molded single-cavity plate (54) is provided with a square hole adapted to the limiting strip, one side wall of the combined molded single-cavity plate (54) is fixedly installed with a side sealing rubber block (543), the other side wall of the combined molded single-cavity plate (54) is provided with a card groove adapted to the side sealing rubber block (543), the bottom of the combined molded single-cavity plate (54) is movably installed with a bottom limiting elastic block (544), and the upper surface of the bottom sealing ring (512) is provided with a card groove adapted to the bottom limiting elastic block (544).

2. The powder metallurgy brake disc production process according to claim 1, characterized in that: A first sealing platform (41) is fixedly mounted on the middle portion of the lower surface of the upper mold (4), a second sealing platform (42) is fixedly mounted on the middle portion of the lower surface of the first sealing platform (41), a forming tube (43) is fixedly mounted on the middle portion of the lower surface of the second sealing platform (42), a forming column (431) is fixedly mounted inside the forming tube (43), and the depth of the forming tube (43) is adapted to the depth of the heat dissipation ring groove (2).

3. The powder metallurgy brake disc production process according to claim 1, characterized in that: A molding cavity (55) is provided on the inner side of the bottom sealing ring (512), an adjustment disk (57) is rotatably mounted between the inner side wall of the lower mold (5) and the outer side wall of the bottom sealing ring (512), a gear ring (571) is fixedly mounted on the outer surface of the adjustment disk (57), and a gear (572) is provided on one side of the upper surface of the mold base (51), and the side surface of the gear (572) and the side surface of the gear ring (571) are meshed with each other.

4. The powder metallurgy brake disc production process according to claim 1, characterized in that: A locking sealing ring (53) is mounted on the upper side of the upper sealing ring (52), and a locking block (531) adapted to the sliding block (542) is fixedly mounted on the lower surface of the locking sealing ring (53).

5. The powder metallurgy brake disc production process according to claim 1, characterized in that: A demoulding push block (56) is provided on the inner wall of the bottom of the mold base (51), a fixing ring (561) is fixedly installed below the demoulding push block (56), a wedge block 1 (562) is fixedly installed on the lower surface of the fixing ring (561), and a wedge block 2 (563) is provided on one side of the wedge block 1 (562).

6. The powder metallurgy brake disc production process according to claim 5, characterized in that: A threaded rod (564) is rotatably mounted on one side surface of the wedge block 2 (563), and the outer surface of the threaded rod (564) is threadedly connected to the side wall of the mold base (51). The upper surface of the sealing bottom plate (511) is provided with a limiting slide groove adapted to the wedge block 2 (563), and a reset telescopic spring sleeve rod (565) is fixedly mounted between the upper surface of the fixing ring (561) and the top of the inner surface of the mold base (51).

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