Casting mold for aluminum-iron composite brake disc and casting method thereof

Abstract

The application discloses a casting mold and a casting method of an aluminum-iron composite brake disc. A forming lower convex part of an upper mold of the mold is provided with a flow dividing cone and a plurality of radial grooves which are uniformly distributed around the flow dividing cone. A side mold assembly comprises a plurality of side mold single blocks which are uniformly distributed along a circular ring. An annular accommodating cavity is formed by a bottom annular recess of the side mold assembly and a lower annular groove of a lower mold. An iron working ring body and an air duct mold core are placed in the annular accommodating cavity. The air duct mold core is placed between the upper iron working ring body and a lower iron working ring body. The upper mold, the side mold assembly, the lower mold, the iron working ring body and the air duct mold core jointly enclose a mold cavity of the aluminum-iron composite brake disc. A gating system comprises a sprue, a vertical gate and a horizontal gate which are sequentially communicated. A top surface of an annular convex part of the lower mold and the radial grooves of the forming lower convex part of the upper mold enclose the horizontal gate. The mold cavity is communicated with the gating system. The aluminum-iron composite brake disc cast by the casting mold and the casting method has good wear resistance and light weight.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of brake discs, and particularly relates to a casting mold and a casting method for an aluminum-iron composite brake disc. BACKGROUND

[0002] A brake system is one of important components of an automobile, and is related to driving safety and personnel life safety. As a key part of an automobile brake system, a brake disc determines the advantages and disadvantages of the automobile brake system and the safety of the automobile and personnel life.

[0003] A brake is used to generate a braking force to hinder the movement or movement tendency of a vehicle in a brake system, and a brake disc is a rotating element in a friction pair of a disc brake, and is a metal disc with two end surfaces working. In addition to having the strength and rigidity required as a component, the brake disc should have a high and stable friction coefficient as much as possible, and appropriate wear resistance, heat resistance, heat dissipation and heat capacity. The brake disc made of traditional gray cast iron has a large weight under a given boundary, and has a large thermal expansion and deformation, and is difficult to meet the potential demand for light weight of a commercial vehicle.

[0004] In order to meet the demand for light weight, reduce the fuel consumption of the whole vehicle and improve the performance of the vehicle, most manufacturers gradually develop light-weight brake discs. Since aluminum alloy is a kind of current light-weight automobile part replacement material, it has good heat capacity and heat conduction performance, and is applied to light-weight brake discs. However, due to the poor wear resistance, the aluminum alloy cannot be directly used as a brake disc material, and therefore, most aluminum-iron composite brake discs are produced by using the aluminum-iron composite method.

[0005] Through a large number of road test experiments and bench test experiments, it is found that the aluminum-iron composite brake disc in the prior art has the problems of poor wear resistance, poor compactness of the aluminum-iron composite and short service life. The above problems are related to the mold and the casting process. Therefore, a suitable casting mold and casting method are needed to be provided to achieve the advantages of good wear resistance, good heat capacity and good heat conduction performance of the cast aluminum-iron composite brake disc while meeting the light weight of the composite brake disc. SUMMARY

[0006] To overcome the above-mentioned deficiencies of the prior art, the first technical problem to be solved by the present application is to provide a casting mold for an aluminum-iron composite brake disc. The cast light-weight aluminum-iron composite brake disc has the advantages of good wear resistance of the brake disc and light weight, and the cast iron part and the aluminum alloy part are tightly combined and not easy to be separated.

[0007] To solve the first technical problem, the application adopts the following technical solutions:

[0008] The application discloses a casting mold for an aluminum-iron composite brake disc, and belongs to the technical field of aluminum-iron composite brake disc casting.

[0009] The upper mold assembly comprises a fixedly connected upper mold connecting plate and an upper mold, wherein a shaped lower convex part is arranged in the middle of the upper mold, a lower convex flow divider is arranged on the bottom surface of the shaped lower convex part, and a plurality of radial grooves are arranged on the bottom surface of the shaped lower convex part and are uniformly distributed around the flow divider.

[0010] The lower mold assembly comprises a fixedly connected lower mold base plate and a lower mold, wherein a lower concave annular groove and an annular convex part are sequentially arranged from the outside to the inside of the lower mold.

[0011] The side mold assembly is clamped between the upper mold and the lower mold, and comprises a plurality of side mold single blocks which are uniformly arranged along a circular ring, wherein a top annular recess is arranged at the top of the side mold assembly, and a bottom annular recess is arranged at the bottom of the side mold assembly, the bottom annular recess and the lower concave annular groove of the lower mold form an annular accommodating cavity, the cast iron working ring body and an air duct mold core are placed in the annular accommodating cavity, the cast iron working ring body is divided into an upper cast iron working ring body and a lower cast iron working ring body, the air duct mold core is placed between the upper cast iron working ring body and the lower cast iron working ring body, and the upper mold, the side mold assembly, the lower mold, the cast iron working ring body and the air duct mold core jointly form a mold cavity of the aluminum-iron composite brake disc.

[0012] The pouring system comprises a sprue, a vertical runner and a horizontal runner which are sequentially communicated, the lower mold base plate is provided with the sprue, the lower mold is provided with the vertical runner, a filter screen is arranged at the vertical runner, the top surface of the annular convex part of the lower mold and the radial grooves of the shaped lower convex part of the upper mold jointly form the horizontal runner, and the mold cavity is communicated with the pouring system.

[0013] The mold opening and closing auxiliary assembly comprises a push plate, a plurality of ejection rods, a plurality of guide columns and a reset member, the push plate is located between the upper mold connecting plate and the upper mold, the ejection rods are fixedly connected with the push plate and pass through the upper mold, the ejection rods can move up and down relative to the upper mold, the guide columns are fixed with the upper mold connecting plate and pass through the push plate, the guide columns can move up and down relative to the push plate, and the reset member resets the push plate.

[0014] Preferably, the cooling system comprises an air cooling system and a water cooling system, the air cooling system is arranged on the side mold assembly, and the water cooling system is arranged on the upper mold.

[0015] Preferably, the water cooling system comprises an external water pipe assembly and an internal annular water channel, the internal annular water channel is arranged in the upper die and corresponds to the top of the cavity of the aluminum-iron composite brake disc, the upper die is provided with a plurality of vertical holes communicating with the internal annular water channel, and the external water pipe assembly comprises cooling pipes connected with the vertical holes respectively and cooling pipe joints connected with the cooling pipes.

[0016] Preferably, the air cooling system comprises an external air pipe assembly and an internal horizontal air hole, the opening of the internal horizontal air hole is located on the side surface of the side die single block, and the external air pipe assembly is installed at the opening of the internal horizontal air hole.

[0017] Preferably, each side die single block is provided with a side-opened weight-reducing cavity, and the internal horizontal air hole is arranged in the upper wall of the weight-reducing cavity.

[0018] Preferably, the side die single block is provided with a side die limiting structure between the side die single block and the lower die and the upper die respectively.

[0019] Preferably, the push plate comprises a fixed dismounting plate and a guide dismounting plate fixedly connected, the upper connecting end of each ejection rod passes through the guide dismounting plate and is fixed to the fixed dismounting plate, and the lower end of the ejection rod passes through the lower die and is in abutment with the end surface of the flange plate part of the aluminum-iron composite brake disc.

[0020] Preferably, the casting mold of the aluminum-iron composite brake disc is provided with a vertical exhaust rod, and the exhaust rod passes through the guide dismounting plate and the upper die.

[0021] Based on the same inventive concept, a second technical problem to be solved by the present application is to provide a method for casting an aluminum-iron composite brake disc, so that the cast lightweight aluminum-iron composite brake disc can meet the structural strength of the brake disc and has the advantages of good wear resistance, light weight, good heat capacity and good heat conduction performance.

[0022] To solve the second technical problem, the present application adopts the following technical solutions:

[0023] A method for casting an aluminum-iron composite brake disc based on the casting mold of the aluminum-iron composite brake disc, the method comprising the following steps:

[0024] a) Melting raw materials: Chemical composition testing is performed on aluminum alloy raw materials and recycled materials. The qualified raw materials are melted. During melting, the proportion of aluminum alloy raw materials is 70% to 75%, and the proportion of recycled materials is 25% to 30%. The melting furnace is gradually heated. When the temperature of the aluminum alloy melt is 685℃ to 710℃, a refining agent is added for refining and degassing. When the temperature of the aluminum alloy melt is between 710℃ and 730℃, a slag remover is evenly sprinkled on the surface of the aluminum alloy melt for slag removal. The mass ratio of the aluminum alloy raw materials to the slag remover is 100:(0.1 to 0.15). Then the temperature is continued to rise to maintain the melting temperature at 730℃ to 750℃.

[0025] The aluminum alloy molten liquid is transferred to a low-pressure machine holding furnace at 720℃~740℃ after passing the test. The aluminum alloy molten liquid held in the low-pressure machine holding furnace is sampled and poured into test bars. The test bars are tested and, if they pass the test, the aluminum alloy molten liquid in the holding furnace is used as the casting liquid. The temperature of the casting liquid in the low-pressure machine holding furnace is maintained at 720℃~725℃.

[0026] b) Core making: Simultaneously with step a), the air duct mold core is made. Before core making, the gap between the top core rod and the loose sand are blown clean with an air gun, and a release agent is sprayed to prevent sand from sticking. Sand is injected into the shell core machine to make the sand core of the air duct mold core. The sand core is then dipped and baked. After the core making is completed, the residual sand is blown clean and a cleaning agent is sprayed on to obtain the air duct mold core.

[0027] c) Pre-treatment molds and components:

[0028] Clean the mold. When the mold temperature reaches 60℃~100℃, use a sandblasting gun to clean the gating system and the cavity.

[0029] Apply thermal insulation coating to the mold. Preheat the mold to a temperature between 150℃ and 250℃, then spray or brush the runner multiple times. Apply the coating to the upper and lower molds using a prepared spray gun, maintaining a 45°–60° angle between the spray gun and the mold, and a spraying distance of 400 mm–600 mm.

[0030] d) Assemble molds and components:

[0031] Assemble the lower mold assembly and fix the lower mold to the lower mold base plate; simultaneously, assemble the upper mold assembly and the opening and closing mold auxiliary assembly, assemble the opening and closing mold auxiliary assembly with the upper mold, and then fix the upper mold to the upper mold connecting plate; place the filter screen in the vertical sprue of the lower mold, and place the upper cast iron working ring, the air duct mold core, and the lower cast iron working ring in sequence within the concave annular groove of the lower mold.

[0032] The mold assembly, the side mold assembly, the upper mold assembly, and the mold opening and closing auxiliary assembly are closed and then die-cast.

[0033] Opening the mold, first opening the side mold assembly, then lifting the upper mold assembly and taking out the aluminum-iron composite brake disc castings together with the opening and closing mold auxiliary assembly, and then the opening and closing mold auxiliary assembly ejects the aluminum-iron composite brake disc castings through the ejector rod;

[0034] e) Take out the aluminum-iron composite brake disc castings, observe and detect, and detect with a flaw detector, polish the flash and burrs at the parting surface of the iron composite brake disc blank that passes the detection, then perform solid solution aging treatment, and finally perform shot blasting treatment.

[0035] Preferably, in the step d), the mold and the cast iron working ring body need to be preheated, the mold is preheated to 240-260 DEG C for the upper mold and 260-300 DEG C for the lower mold, and the cast iron working ring body is preheated to 150-250 DEG C.

[0036] After adopting the above technical scheme, the application has the following beneficial effects:

[0037] The aluminum-iron composite brake disc casting mold has the following structure: the middle part of the upper mold is provided with a forming lower convex part, the bottom surface of the forming lower convex part is provided with a lower convex flow divider, and the bottom surface is provided with a plurality of radial grooves distributed around the flow divider; the lower mold is sequentially provided with a lower concave annular groove and an annular convex part from the outside to the inside; the side mold assembly is clamped between the upper mold and the lower mold, and the side mold assembly includes a plurality of side mold single blocks, which are evenly distributed along the circular ring; the top of the side mold assembly is provided with a top annular recess, and the bottom is provided with a bottom annular recess; the bottom annular recess and the lower concave annular groove of the lower mold form an annular accommodating cavity; the cast iron working ring body and the air duct mold core are placed in the annular accommodating cavity; the cast iron working ring body is divided into an upper cast iron working ring body and a lower cast iron working ring body; the air duct mold core is placed between the upper cast iron working ring body and the lower cast iron working ring body; the upper mold, the side mold assembly, the lower mold, the cast iron working ring body and the air duct mold core jointly form a mold cavity of the aluminum-iron composite brake disc; the gating system includes a sprue, a vertical gate and a horizontal gate which are sequentially communicated; the bottom plate of the lower mold is provided with a sprue; the lower mold is provided with a vertical gate; the vertical gate is provided with a filter screen; the top surface of the annular convex part of the lower mold and the radial grooves of the forming lower convex part of the upper mold form a horizontal gate; and the mold cavity is connected with the gating system.

[0038] The cast iron working ring body is placed in the mold cavity in advance, and then the aluminum alloy pouring liquid is poured, so that the cast aluminum-iron composite brake disc cast iron part and the aluminum alloy part are combined tightly and are not easy to separate.

[0039] The gating system has the advantages of less material and high yield because the sprue, vertical runner and horizontal runner are all built-in runners. The sprue is located on the lower die bottom plate, the molten aluminum alloy is poured from the bottom of the mold during pouring, and single-channel filling is adopted. Because the upper mold is provided with a flow divider and a plurality of radial grooves distributed around the flow divider, i.e. a plurality of horizontal runners are distributed around the flow divider, the molten aluminum alloy flows stably during pouring to prevent turbulence, and in turn prevent the poured product from being loose and porous, and the flow divider can limit the filter screen from being washed away when the molten liquid enters.

[0040] The side mold assembly can reduce the sand core used for forming the middle connecting barrel part and the flange plate part of the brake disc, facilitate mold opening, and avoid the difficulty in ejecting the casting due to the deep cavity during mold opening, thereby improving the yield. In addition, the side mold single block can be taken out individually for easy cleaning. Each side mold single block of the side mold assembly is made of an iron mold and can be used repeatedly, thereby saving cost.

[0041] The cooling system includes an air cooling system and a water cooling system, and adopts a double cooling system, which can ensure that the casting is cooled and solidified in sequence, and avoid the deformation and low structural strength of the product caused by stress concentration due to cooling.

[0042] In summary, the cast lightweight aluminum-iron composite brake disc has the advantages of good brake disc wear resistance and light weight, and the cast iron part and the aluminum alloy part are tightly combined and not easy to separate. In addition, the cast lightweight aluminum-iron composite brake disc has sufficient structural strength. BRIEF DESCRIPTION OF DRAWINGS

[0043] Figure 1 is a structural schematic view of an aluminum-iron composite brake disc;

[0044] Figure 2 is a structural schematic view of an aluminum-iron composite brake disc;

[0045] Figure 3 is a structural schematic view of a casting mold of the aluminum-iron composite brake disc of the present application;

[0046] Figure 4 is a sectional view of a casting mold of the aluminum-iron composite brake disc of the present application;

[0047] Figure 5 is another sectional view of a casting mold of the aluminum-iron composite brake disc of the present application (part of the assembly is omitted);

[0048] Figure 6 is Figure 3 is an exploded structural schematic view of part of the casting mold of the aluminum-iron composite brake disc;

[0049] Figure 7 is Figure 6 is a structural schematic view of an upper mold;

[0050] Figure 8 This is a cross-sectional view of a single side mold piece;

[0051] Figure 9 This is a schematic diagram of the initial state of the casting mold for the aluminum-iron composite brake disc.

[0052] Figure 10 This is a schematic diagram of the final state of the casting mold for the aluminum-iron composite brake disc after mold opening.

[0053] In the diagram: 1. Aluminum alloy brake disc body; 101. Annular disc body; 102. Intermediate connecting cylinder; 103. Flange; 2. Cast iron working ring; 201. First brake ring; 202. Second brake ring; 203. Support connecting column; 204. Upper cast iron working ring; 205. Lower cast iron working ring; 3. Upper mold connecting plate; 4. Upper mold; 401. Forming lower protrusion; 402. Diverter cone; 403. Radial groove; 404. First limiting groove; 5. Lower mold; 501. Recessed annular groove; 502. Annular protrusion; 503. Vertical runner; 504. Second limiting groove; 6. Lower mold base plate; 601. Gate; 7. Side mold single piece; 701, top annular concave; 702, bottom annular concave; 703, weight reduction cavity; 704, first limiting protrusion; 705, second limiting protrusion; 8, air duct mold core; A, cavity; 9, push plate; 91, fixed disassembly plate; 92, guide disassembly plate; 10, ejector rod; 11, guide post; 12, external water pipe assembly; 121, cooling pipe; 122, cooling pipe connector; 13, built-in annular water channel; 14, ventilation pipe assembly; 15, transverse ventilation channel; 16, reset part; 161, reset rod; 162, reset spring; 17, exhaust rod; 171, exhaust groove; 18, filter screen; B, aluminum-iron composite brake disc casting. Detailed Implementation

[0054] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments.

[0055] A casting mold for an aluminum-iron composite brake disc, used for casting aluminum-iron composite brake discs, for example, it can be used to cast such as... Figure 1 and Figure 2The aluminum-iron composite brake disc shown includes an aluminum alloy brake disc body 1 and a cast iron working ring body 2. The aluminum alloy brake disc body 1 and the cast iron working ring body 2 are cast as one piece. The aluminum alloy brake disc body includes an integrally formed annular disc portion 101, an intermediate connecting cylinder portion 102, and a flange portion 103. The cast iron working ring body 2 includes two brake rings arranged opposite each other, namely a first brake ring 201 and a second brake ring 202. The first brake ring 201 and the second brake ring 202 are connected and fixed by a plurality of supporting connecting columns 203. The annular disc portion 101 is located between the first brake ring 201 and the second brake ring 202, and the plurality of supporting connecting columns 203 pass through and connect the annular disc portion 101.

[0056] Embodiments of the present invention disclose, as follows Figure 3 and Figure 4 The image shows a casting mold for an aluminum-iron composite brake disc. The casting mold includes an upper mold assembly, a lower mold assembly, a side mold assembly, an opening and closing mold auxiliary assembly, a gating system, and a cooling system. The upper mold assembly includes a fixedly connected upper mold connecting plate 3 and an upper mold 4, as shown. Figure 7 As shown, the upper mold 4 has a forming lower protrusion 401 in the middle. The bottom surface of the forming lower protrusion 401 is provided with a lower protruding flow divider cone 402 and a plurality of radial grooves 403 evenly distributed around the flow divider cone 402 are opened on the bottom surface. In this embodiment, there are four radial grooves 403, all of which lead to the outer periphery of the flow divider cone 402.

[0057] like Figure 6 As shown, the lower mold assembly includes a lower mold base plate 6 and a lower mold 5 that are fixedly connected. The lower mold 5 and the lower mold base plate 6 are fixedly connected together by screws. The lower mold 5 is provided with a recessed annular groove 501 and an annular protrusion 502 from the outside to the inside.

[0058] The side mold assembly is clamped between the upper mold 4 and the lower mold 5, and the side mold assembly comprises a plurality of side mold blocks 7 which are uniformly arranged along a circular ring, and the top of the side mold assembly is provided with a top annular recess 701, and the bottom of the side mold assembly is provided with a bottom annular recess 702, the bottom annular recess 702 and the lower recessed annular groove 501 of the lower mold 5 form an annular accommodating cavity, the cast iron working ring body 2 and the air duct mold core 8 are placed in the annular accommodating cavity, the cast iron working ring body 2 is divided into an upper cast iron working ring body 204 and a lower cast iron working ring body 205 from the middle position of the support connecting column 203, and the air duct mold core 8 is placed between the upper cast iron working ring body 204 and the lower cast iron working ring body 205, the upper mold 4, the side mold assembly, the lower mold 5, the cast iron working ring body 2 and the air duct mold core 8 jointly enclose a mold cavity A of the aluminum-iron composite brake disc; the pouring system comprises a sprue 601, a vertical runner 503 and a horizontal runner which are sequentially communicated, the lower mold bottom plate 6 is provided with the sprue 601, the lower mold 5 is provided with the vertical runner 503, the vertical runner 503 is provided with a filter screen 18, the top surface of the annular protruding portion 502 of the lower mold 5 and the radial recess 403 of the forming lower protruding portion 401 of the upper mold 4 enclose the horizontal runner, and the mold cavity A is communicated with the pouring system.

[0059] The filter screen 17 of the present application adopts a mesh diameter of 0.5 mm, and the mesh adopts a specification of 1.5*1.5 mm or 2*2 mm. The filter screen 17 can filter out impurities in the pouring liquid.

[0060] As shown in the figure, Figure 5 The opening and closing mold auxiliary assembly comprises a push plate 9, a plurality of ejection rods 10, a plurality of guide columns 11 and a reset member 16, the push plate 9 is located between the upper mold connecting plate 3 and the upper mold 4, the ejection rod 10 is fixedly connected with the push plate 9 and penetrates through the upper mold 4, the ejection rod 10 can move up and down relative to the upper mold 4, the guide column 11 is fixed with the upper mold connecting plate 3 and penetrates through the push plate 9, the guide column 11 can move up and down relative to the push plate 9, and the reset member resets the push plate 9. In the embodiment, the reset member comprises a reset rod 161 and a reset spring 162 which is sleeved outside the reset rod. The top end of the guide column 11 is provided with a limiting block to prevent the spring from toppling the fixed disassembly plate during the resetting process.

[0061] Before casting, the ejection rod 10, the exhaust rod 17, the guide column 11 and the guide disassembly plate 92 are inserted into the upper mold 4, and then the fixed disassembly plate 91 is pressed, the ejection rod 10, the exhaust rod 17 and the guide column 11 are all provided with a large end, and after being pressed by the fixed disassembly plate, the above rod members are locked and fixed in the vertical direction.

[0062] When the mold is opened, first, the four side mold blocks 7 of the side mold assembly move outward to open, then the upper mold assembly moves upward, the upper mold 4 lifts the formed cast aluminum-iron composite brake disc casting, then under the action of external pressure, the fixed disassembly plate 91 moves downward along the guide column 11, pushes the ejection rod 10 to move downward to eject the casting, and after the ejection is completed, under the action of the reset spring, the fixed disassembly plate 91 and the ejection rod 10 parts are reset along the guide column 11.

[0063] The cooling system includes a wind cooling system and a water cooling system, the wind cooling system is arranged in the side mold assembly, and the water cooling system is arranged in the upper mold 4. The double cooling system can ensure that the casting is sequentially cooled and solidified, and avoid product deformation and low structural strength caused by stress concentration due to uneven cooling.

[0064] As shown in Figure 6 , the water cooling system includes an external water pipe assembly 12 and an internal circular ring water channel 13, the internal circular ring water channel 13 is arranged in the upper mold 4, and corresponds to the top of the cavity A of the aluminum-iron composite brake disc, the upper mold 4 is provided with a plurality of vertical holes in communication with the internal circular ring water channel 13, and the external water pipe assembly 12 includes a cooling pipe 121 connected with the vertical hole and a cooling pipe joint 122 connected with the cooling pipe 121.

[0065] The wind cooling system includes an external air pipe assembly 14 and an internal horizontal air hole 15, the opening of the internal horizontal air hole 15 is located on the side surface of the side mold block 7, and the external air pipe assembly 14 is installed at the opening of the internal horizontal air hole 15.

[0066] The external water pipe assembly 12 enters the upper mold from the top of the upper mold, the internal circular ring water channel 13 in the upper mold is arranged close to the flange plate part 103 of the brake disc, which can ensure sequential solidification after the mold filling is completed, and a cooling plate is arranged on the outside of the mold to cool the circulating water. The wind cooling system of the side mold block 7 further cools the mold and the brake disc casting, and the air external air pipe assembly 14 enters the internal horizontal air hole 15 for local cooling. It is arranged at the thick part of the flange plate part 103 of the brake disc to further ensure sequential solidification. Figure 6 and Figure 8 As shown in the drawings, it can be seen that the internal horizontal air hole 15 of the wind cooling system is arranged in the circumferential direction around the flange plate part 103, and is opposite to the thick part of the flange plate part 103 of the brake disc, and the internal circular ring water channel 13 of the water cooling system is located above the top surface of the flange plate part 103, which can be closer to the flange plate part 103, and has good cooling effect.

[0067] The solidification sequence after pouring is as follows: the pouring liquid (the annular disc body part 101 to be formed) poured in the annular accommodating cavity at the cast iron working ring body 2 and the air duct mold core 8 solidifies first, then the pouring liquid (the intermediate connecting cylinder part 102 to be formed) between the upper side mold assembly and the forming lower convex part 401 of the upper mold 4 solidifies, and finally the pouring liquid at the gate 601 and the vertical sprue 503 solidifies. Since the flange disc part 103 has a thick structure, the pouring liquid is more at this position after pouring, and only natural solidification is very time-consuming, and it is easy to cause porosity and loose, and it is difficult to ensure the casting quality. In order to ensure the sequential solidification of the aluminum-iron composite brake disc in the above sequence, the air cooling system and the water cooling system are arranged.

[0068] Each side mold single block 7 is provided with a side-opening weight-reducing cavity 703, and the built-in transverse ventilation hole 15 is arranged in the upper wall of the weight-reducing cavity 703. The weight-reducing cavity 703 saves material and reduces weight on the one hand, and facilitates heat dissipation on the other hand.

[0069] The side mold single block 7 is provided with a side mold limiting structure between the lower mold 5 and the upper mold 4. The side mold limiting structure includes a limiting recess and a limiting protrusion. The bottom of the upper mold 4 is provided with a first limiting recess 404 near the four edges, the top of the lower mold 5 is provided with a second limiting recess 504 near the four edges, the top of the side mold single block 7 is provided with a first limiting protrusion 704 corresponding to the first limiting recess 404, and the bottom of the side mold single block 7 is provided with a second limiting protrusion 705 corresponding to the second limiting recess 504. The side mold limiting structure between the side mold single block 7 and the lower mold 5 ensures the position accuracy when the side mold assembly is closed from the side to the inside of the lower mold, and the side mold limiting structure between the side mold single block 7 and the upper mold 4 ensures the alignment accuracy of the upper mold and the side mold assembly when the upper mold is closed from the top to the side mold assembly.

[0070] As shown in Figure 5 , the push plate 9 includes a fixed disassembly plate 91 and a guide disassembly plate 92 fixedly connected, the fixed disassembly plate 91 and the guide disassembly plate 92 are connected by bolts, the upper connecting end of the plurality of ejection rods 10 passes through the guide disassembly plate 92 and is fixed to the fixed disassembly plate 91, and the lower end of the ejection rod 10 passes through the lower mold 5 and is pushed to the end face of the flange disc part 103 of the aluminum-iron composite brake disc.

[0071] As shown in Figure 6 , the casting mold of the aluminum-iron composite brake disc is provided with a vertical exhaust rod 17, and the exhaust rod 17 passes through the guide disassembly plate 92 and the upper mold 4. The ejection rod 10 and the exhaust rod 17 are alternately and partially distributed along the circumference on the upper mold, the ejection rod 10 corresponds to the upper side of the flange disc part 103 of the brake disc, and the ejection force of the ejection rod 10 can be uniformly distributed on the flange disc part 103 of the brake disc. The exhaust rod 17 is partially distributed along the circumference to exhaust more uniformly.

[0072] The exhaust rod 17 and the exhaust groove 171 on the exhaust rod 17 are formed by wire cutting, and the groove type of the exhaust groove 171 is generally U-shaped, V-shaped or rectangular, and the depth and width of the exhaust groove are not more than 0.1 mm.

[0073] The side mold assembly is pushed or pulled by a hydraulic cylinder to close or open the mold, and the upper mold assembly is also pushed or pulled by a hydraulic cylinder to close or open the mold.

[0074] As shown in Figure 9 and Figure 10 When the mold is opened, the four side mold blocks 7 of the side mold assembly move outward to open under the action of the hydraulic rod, and the upper mold 4 lifts with the formed cast aluminum-iron composite brake disc casting. Then, under the action of external pressure, the fixed disassembly plate 91 moves downward along the guide column 11, pushes the ejection rod 10 to move downward to eject the casting, and after the ejection is completed, the fixed disassembly plate 91 and the ejection rod 10 parts are reset along the guide column 11 under the action of the reset spring,

[0075] When the mold is closed, the four side mold blocks 7 of the side mold assembly gradually move inward under the action of the external hydraulic rod, and then the side mold blocks 7 are pushed to the predetermined position under the limiting action of the second limiting protrusion 705 at the bottom of the side mold block 7 and the second limiting groove 504 on the lower mold 5, and then the upper mold assembly falls, and the first limiting protrusion 704 at the top of the side mold block 7 and the first limiting groove 404 of the upper mold 4 are limited to complete the closing of the mold.

[0076] Because of the existence of the side mold assembly, the sand core at the middle connecting cylinder part 102 and the flange plate part 103 of the brake disc can be reduced, and when the mold is opened, the casting can be easily ejected because the cavity is not too deep, and the yield is improved. In addition, the side mold block can be taken out individually for easy cleaning. Each side mold block 7 of the side mold assembly adopts an iron mold which can be used repeatedly, saving cost.

[0077] The pouring system of the present application comprises a sprue 601, a vertical runner 503 and a horizontal runner which are sequentially communicated, and are all built-in runners, which saves material and has high yield. The sprue 601 is located on the lower mold bottom plate 6, and the aluminum-iron composite brake disc is poured from below the mold, and a single channel is used for filling. The horizontal runner has four, and a flow dividing cone is arranged at the bottom of the forming lower convex part 401 of the upper mold 4. On the one hand, it can prevent turbulent flow to make the aluminum alloy melt flow smoothly, thereby preventing the poured product from being loose and having holes, and on the other hand, it can limit the filter screen to a certain extent to prevent the filter screen from being washed away when the pouring liquid enters.

[0078] As shown in Figure 4As shown, the bottom annular inner recess 702 of the side mold assembly bottom forms an annular accommodating cavity with the lower annular recess 501 of the lower mold 5, and the cast iron working ring body 2 is placed in the annular accommodating cavity, the cast iron working ring body 2 is divided into an upper cast iron working ring body 204 and a lower cast iron working ring body 205 from the middle position of the support connecting column 203, and the air duct mold core 8 is placed between the upper cast iron working ring body 204 and the lower cast iron working ring body 205, the annular accommodating cavity, the cast iron working ring body 2 and the air duct mold core 8 are sand core matched to form a mold cavity of the aluminum alloy material part of the aluminum-iron composite brake disc, so that the cast aluminum-iron composite brake disc is tightly combined with the aluminum alloy material part and is not easy to separate, the first brake ring body 201 and the second brake ring body 202 of the cast iron working ring body 2 are respectively located on both sides of the aluminum annular disc body part 101 of the aluminum alloy brake disc, the brake pad is in friction contact with the cast iron working ring body 2 during braking, the wear resistance is high, and the aluminum alloy material part is relatively light, so that the wear resistance is ensured and the overall weight is reduced.

[0079] The cast aluminum-iron composite brake disc cast by the aluminum-iron composite brake disc casting mold is connected between the annular disc body part 101 of the aluminum alloy brake disc body and the cast iron working ring body 2 through a plurality of support connecting columns 203, the support connecting columns 203 have a certain draft angle, and the tightness between the annular disc body part 101 of the aluminum alloy material and the cast iron working ring body 2 can be enhanced.

[0080] The cast aluminum-iron composite brake disc cast by the aluminum-iron composite brake disc casting mold greatly reduces the overall weight on the basis of meeting the wear resistance and heat dissipation performance, and realizes the lightweight of the aluminum-iron composite brake disc.

[0081] A method for casting an aluminum-iron composite brake disc based on the aluminum-iron composite brake disc casting mold, the method comprising the following steps:

[0082] a) melting raw materials: the aluminum alloy raw material and the recycled material are subjected to chemical component inspection, and the raw materials passing the inspection are melted, during the melting, the aluminum alloy raw material accounts for 70% to 75%, and the recycled material accounts for 25% to 30%, the melting furnace is gradually heated, the refining agent is added when the aluminum alloy melt temperature is 685 DEG C to 710 DEG C for refining and degassing, the deslagging agent is uniformly sprinkled on the surface of the aluminum alloy melt when the aluminum alloy melt temperature is 710 DEG C to 730 DEG C for deslagging, the mass ratio of the aluminum alloy raw material to the deslagging agent is 100: (0.1 to 0.15), and then the temperature is continuously raised, so that the melting temperature is maintained at 730 DEG C to 750 DEG C;

[0083] When degassing, the degassing machine rotates through the graphite rotor to make the aluminum alloy melt form a vortex, the refining agent particles are uniformly sent to the center of the aluminum alloy melt vortex under the action of the feeder, and through the combined action of mechanical stirring and inert gas, the refining agent is in contact with the aluminum alloy melt to react, so as to achieve the effect of refining and deslagging. And the inert gas is pressed into the aluminum alloy melt through the rotor and is scattered, uniformly distributed in the aluminum alloy melt, and the hydrogen bubbles in it can adsorb non-metallic impurities and float up to achieve the effect of degassing.

[0084] When deslagging, after reaching the specified temperature of 710-730℃, open the deslagging door, evenly sprinkle the deslagging agent on the surface of the aluminum alloy melt, and after uniform stirring, carry out deslagging treatment.

[0085] Aluminum alloy melt transfer, the melt that has passed the detection is transferred to the low-pressure machine holding furnace at 720-740℃ for holding, the melt in the low-pressure machine holding furnace is sampled and cast into test bars, the test bars are detected, and after the detection is qualified, the melt in the holding furnace is used as the casting liquid, and the temperature of the casting liquid in the low-pressure machine is kept at 720-725℃;

[0086] b) Core making: simultaneously with step a), making the air duct mold core 8, before core making, blowing the gap between the top core rod and the loose sand with an air gun, spraying demolding agent to prevent sand sticking, shooting sand into the shell core machine to make the sand core of the air duct mold core 8, and immersing and baking the sand core, after core making is completed, blowing the residual sand, spraying cleaner, and obtaining the air duct mold core 8;

[0087] c) Pre-treatment of mold and parts:

[0088] Cleaning the mold, when the mold temperature reaches 60-100℃, using a sandblasting gun to clean the gating system and the cavity;

[0089] Applying heat preservation paint to the mold, preheating the mold to a temperature of 150-250℃, multiple spraying or brushing of the runner, spraying the upper mold and the lower mold using a prepared spray gun at an angle of 45-60° with the mold, and the spraying distance is 400-600mm,

[0090] d) Assembling the mold and parts:

[0091] Assembling the lower mold assembly, fixing the lower mold 5 on the lower mold base plate 6; at the same time, assembling the upper mold assembly and the mold opening and closing auxiliary assembly, assembling the mold opening and closing auxiliary assembly with the upper mold 4, and then fixing and connecting the upper mold 4 with the upper mold connecting plate 3; placing the filter screen between the vertical sprue of the lower mold, and sequentially placing the upper cast iron working ring body 204, the air duct mold core 8, and the lower cast iron working ring body 205 in the annular protruding part 502 of the lower mold 5,

[0092] Mold closing and die casting, mold closing of the lower mold assembly, the side mold assembly, the upper mold assembly, and the mold opening and closing auxiliary assembly, and then die casting;

[0093] Opening the mold, first opening the side mold assembly, then lifting the upper mold assembly and taking out the aluminum-iron composite brake disc castings together with the mold opening and closing auxiliary assembly, and then the mold opening and closing auxiliary assembly pushes out the aluminum-iron composite brake disc castings B through the ejection rod 10;

[0094] e) Take out the aluminum-iron composite brake disc castings B blank, observe and detect, and detect with a flaw detector, polish and clean the flash and burrs at the parting surface of the iron composite brake disc blank that passes the detection, then perform solid solution aging treatment, and finally perform shot blasting treatment.

[0095] In the step d), the mold and the cast iron working ring body 2 also need to be preheated. The mold is preheated to make the temperature of the upper mold reach 240-260℃ and the temperature of the lower mold reach 260-300℃, and the cast iron working ring body 2 is preheated to reach 150-250℃.

[0096] After the casting is formed and cut, the sprue and the riser are removed by reaming. The corresponding diameter reamer is selected to cut off the sprue and the riser.

[0097] For example, the aluminum-iron composite brake disc disclosed in patent application No. 202320998916.5, entitled Aluminum-iron composite brake disc, can be cast by the casting mold and the casting method of the present application.

[0098] The aluminum-iron composite brake disc manufactured by the manufacturing method of the aluminum-iron composite brake disc of the present application has a tightly combined iron casting part and aluminum alloy material part, is not easy to separate, has high wear resistance, and has a light overall weight.

[0099] The above only describes the preferred embodiments of the present application and is not intended to limit the present application. Any modifications, equivalent replacements and improvements made within the spirit and principles of the present application shall be included in the protection scope of the present application.

Claims

1. A casting mold for an aluminum-iron composite brake disc, used for casting an aluminum-iron composite brake disc, wherein the aluminum-iron composite brake disc comprises an aluminum alloy brake disc body and a cast iron working ring, and the casting mold comprises an upper mold assembly, a lower mold assembly, a side mold assembly, an opening and closing mold auxiliary assembly, a gating system, and a cooling system, characterized in that: The upper mold assembly includes an upper mold connecting plate and an upper mold that are fixedly connected. The upper mold has a forming lower protrusion in the middle. The bottom surface of the forming lower protrusion is provided with a lower protruding flow divider cone, and multiple radial grooves are evenly distributed around the flow divider cone on the bottom surface. The lower mold assembly includes a lower mold base plate and a lower mold that are fixedly connected. The lower mold is provided with a recessed annular groove and an annular protrusion from the outside to the inside. The side mold assembly is sandwiched between the upper mold and the lower mold. The side mold assembly includes multiple side mold pieces, which are evenly distributed along a circular ring. The side mold assembly has a top annular recess and a bottom annular recess. The bottom annular recess and the lower annular groove of the lower mold form an annular receiving cavity. The cast iron working ring and the air duct mold core are placed in the annular receiving cavity. The cast iron working ring is divided into an upper cast iron working ring and a lower cast iron working ring. The air duct mold core is placed between the upper cast iron working ring and the lower cast iron working ring. The upper mold, the side mold assembly, the lower mold, the cast iron working ring, and the air duct mold core together form the cavity of the aluminum-iron composite brake disc. The gating system includes a gate, a vertical runner, and a horizontal runner that are connected in sequence. The lower mold base plate has the gate, the lower mold has the vertical runner, and a filter screen is provided at the vertical runner. The top surface of the annular protrusion of the lower mold and the radial groove of the forming lower protrusion of the upper mold form the horizontal runner. The cavity is connected to the gating system. The mold opening and closing auxiliary assembly includes a push plate, multiple ejector rods, multiple guide pillars, and a reset component. The push plate is located between the upper mold connecting plate and the upper mold. The ejector rods are fixedly connected to the push plate and pass through the upper mold. The ejector rods can move up and down relative to the upper mold. The guide pillars are fixed to the upper mold connecting plate and pass through the push plate. The guide pillars can move up and down relative to the push plate. The reset component resets the push plate.

2. The casting mold for the aluminum-iron composite brake disc as described in claim 1, characterized in that, The cooling system includes an air-cooling system and a water-cooling system. The air-cooling system is disposed on the side mold assembly, and the water-cooling system is disposed on the upper mold.

3. The casting mold for the aluminum-iron composite brake disc as described in claim 2, characterized in that, The water cooling system includes an external water pipe assembly and an internal annular water channel. The internal annular water channel is provided inside the upper mold and corresponds to the cavity above the aluminum-iron composite brake disc. The upper mold has multiple vertical holes communicating with the internal annular water channel. The external water pipe assembly includes cooling pipes connected to the vertical holes and cooling pipe connectors connected to the cooling pipes.

4. The casting mold for the aluminum-iron composite brake disc as described in claim 2, characterized in that, The air-cooling system includes an external ventilation pipe assembly and a built-in transverse ventilation channel. The opening of the built-in transverse ventilation channel is located on the side of the side mold block, and the external ventilation pipe assembly is installed at the opening of the built-in transverse ventilation channel.

5. The casting mold for the aluminum-iron composite brake disc as described in claim 4, characterized in that, Each of the side molds is provided with a weight-reducing cavity with a side opening, and the built-in transverse ventilation channel is opened in the upper wall of the weight-reducing cavity.

6. The casting mold for the aluminum-iron composite brake disc as described in claim 1, characterized in that, A side mold limiting structure is provided between the side mold block and the lower mold and the upper mold, respectively.

7. The casting mold for the aluminum-iron composite brake disc as described in claim 1, characterized in that, The push plate includes a fixed disassembly plate and a guide disassembly plate that are fixedly connected. The upper connecting ends of the plurality of ejector rods pass through the guide disassembly plate and are fixed to the fixed disassembly plate. The lower ends of the ejector rods pass through the lower mold and push against the end face of the aluminum-iron composite brake disc flange.

8. The casting mold for the aluminum-iron composite brake disc as described in claim 7, characterized in that, The casting mold of the aluminum-iron composite brake disc is equipped with a vertical exhaust rod, which passes through the guide disassembly plate and the upper mold.

9. A method for casting an aluminum-iron composite brake disc, characterized in that, The casting mold based on the aluminum-iron composite brake disc of claim 1 includes the following steps: a) Melting raw materials: Chemical composition testing is performed on aluminum alloy raw materials and recycled materials. The qualified raw materials are melted. During melting, the proportion of aluminum alloy raw materials is 70% to 75%, and the proportion of recycled materials is 25% to 30%. The melting furnace is gradually heated. When the temperature of the aluminum alloy melt is 685℃ to 710℃, a refining agent is added for refining and degassing. When the temperature of the aluminum alloy melt is between 710℃ and 730℃, a slag remover is evenly sprinkled on the surface of the aluminum alloy melt for slag removal. The mass ratio of the aluminum alloy raw materials to the slag remover is 100:(0.1 to 0.15). Then the temperature is continued to rise to maintain the melting temperature at 730℃ to 750℃. The aluminum alloy molten liquid is transferred to a low-pressure machine holding furnace at 720℃~740℃ after passing the test. The aluminum alloy molten liquid held in the low-pressure machine holding furnace is sampled and poured into test bars. The test bars are tested and, if they pass the test, the aluminum alloy molten liquid in the holding furnace is used as the casting liquid. The temperature of the casting liquid in the low-pressure machine holding furnace is maintained at 720℃~725℃. b) Core making: Simultaneously with step a), the air duct mold core is made. Before core making, the gap between the top core rod and the loose sand are blown clean with an air gun, and a release agent is sprayed to prevent sand from sticking. Sand is injected into the shell core machine to make the sand core of the air duct mold core. The sand core is then dipped and baked. After the core making is completed, the residual sand is blown clean and a cleaning agent is sprayed on to obtain the air duct mold core. c) Pre-treatment molds and components: Clean the mold. When the mold temperature reaches 60℃~100℃, use a sandblasting gun to clean the gating system and the cavity. Apply thermal insulation coating to the mold. Preheat the mold to a temperature between 150℃ and 250℃, then spray or brush the runner multiple times. Apply the coating to the upper and lower molds using a prepared spray gun, maintaining a 45°–60° angle between the spray gun and the mold, and a spraying distance of 400 mm–600 mm. d) Assemble molds and components: Assemble the lower mold assembly and fix the lower mold to the lower mold base plate; simultaneously, assemble the upper mold assembly and the opening and closing mold auxiliary assembly, assemble the opening and closing mold auxiliary assembly with the upper mold, and then fix the upper mold to the upper mold connecting plate; place the filter screen in the vertical sprue of the lower mold, and sequentially place the upper cast iron working ring, the air duct mold core, and the lower cast iron working ring in the concave annular groove of the lower mold. The mold assembly, the side mold assembly, the upper mold assembly, and the mold opening and closing auxiliary assembly are closed and then die-cast. To open the mold, first open the side mold assembly, then lift the upper mold assembly along with the mold opening and closing auxiliary assembly and the aluminum-iron composite brake disc casting. Then, the mold opening and closing auxiliary assembly ejects the aluminum-iron composite brake disc casting through the ejector rod. e) Remove the aluminum-iron composite brake disc casting, observe and inspect it, and use a flaw detector to inspect it. Grind and clean the burrs and flash at the parting surface of the iron composite brake disc blank that has passed the inspection, then perform solution aging treatment, and finally perform shot blasting treatment.

10. The method for casting an aluminum-iron composite brake disc as described in claim 9, characterized in that, In step d), it is also necessary to preheat the mold and the cast iron working ring. Preheat the mold to 240°C to 260°C for the upper mold and 260°C to 300°C for the lower mold, and preheat the cast iron working ring to 150°C to 250°C.

Images