CN215998698U - Bottom casting device for preparing particle reinforced aluminum matrix composite - Google Patents

Abstract

The utility model relates to a bottom casting device for preparing a particle reinforced aluminum matrix composite, which comprises a casting opening, wherein a casting head is replaceably arranged on the casting opening, and the casting head comprises an installation section and a fragmentation section; an impact device for breaking the fragmentation section is arranged in the furnace body; the bottom of the furnace body is provided with a movable platform, and the movable platform is provided with a die and a waste residue groove; a movable platform is utilized, a waste residue groove is used for containing crushed fragmentation sections and rear part melt containing slag, and a mould is used for containing front part uniform melt flowing out of a casting head; and a cooling system is arranged on the movable platform at a position corresponding to the bottom of the mold.

Description

Bottom casting device for preparing particle reinforced aluminum matrix composite

Technical Field

The utility model relates to preparation of an aluminum matrix composite, in particular to a bottom casting device for preparing a particle reinforced aluminum matrix composite.

Background

Aluminum matrix composites have become a hot spot in recent years due to their excellent properties such as high specific strength, specific stiffness, wear resistance, low thermal expansion coefficient, and good thermal conductivity and dimensional stability. The particle reinforced aluminum matrix composite represented by SiC can optimize the performance of the low-cost aluminum matrix composite through the content, the size and the like of particles, and has been a breakthrough in the fields of aerospace, electronic packaging, automobile manufacturing, high-speed trains and the like.

The main processes for preparing the aluminum matrix composite material at present comprise stirring casting, powder metallurgy, pressure infiltration and the like. The stirring casting method is characterized in that matrix metal is melted and then forms vortex through mechanical or electromagnetic stirring, added reinforcing phase particles are rolled into the molten metal under the action of the vortex to obtain evenly distributed melt, and the melt is cast under certain conditions to obtain the composite material. Compared with powder metallurgy and pressure infiltration, the method has the advantages of simple equipment and process, high production efficiency, low cost and capability of producing components with complex shapes in large scale, and is one of the most potential processes for realizing industrial large-scale production.

The casting process used in the stirring casting in the prior art includes gravity casting, suction casting by a counter-gravity casting method, counter-pressure casting and the like, and at present, the performance of the composite material prepared by the counter-gravity casting method is better, but the counter-gravity casting method has higher requirements on equipment, higher cost and lower production efficiency, and is not beneficial to large-scale industrial production, so that a gravity casting device and a method capable of improving the casting performance and the production efficiency of the composite material are needed.

SUMMERY OF THE UTILITY MODEL

The utility model aims to provide a bottom casting device for preparing particle reinforced aluminum matrix composite, which improves the casting performance of the composite and improves the production efficiency aiming at the current situation of the prior art.

The technical scheme adopted by the utility model for solving the technical problems is as follows: the bottom casting device for preparing the particle reinforced aluminum matrix composite comprises a furnace body, wherein a smelting container is arranged in the furnace body, and the bottom of the smelting container is provided with a casting opening with a melt flow channel; a secondary feeding device, a heating temperature control device and a stirring device are matched with the smelting container; a casting head is replaceably arranged with the casting opening, and comprises a mounting section used for matching with the melt runner and a fragile fragmentation section; an impact device for breaking the fragmentation section is arranged in the furnace body; the bottom of the furnace body is provided with a movable platform, and the movable platform is provided with a mold and a waste residue groove; when the movable platform is located at the first position, the waste residue groove is used for containing the smashed fragmentation section, the mold is used for containing the front part uniform melt flowing out of the casting head, and when the movable platform is located at the second position, the waste residue groove is used for containing the rear part melt containing the molten slag; and a cooling system is arranged on the movable platform at a position corresponding to the bottom of the mold.

For better heat preservation, the smelting container is preferably a graphite crucible.

In order to facilitate replacement and disassembly of the casting head, the mounting section of the casting head is an external thread section, so that the mounting section is in fit connection with the corresponding internal thread of the melt runner. The casting head with the structure can be replaced by a new casting head before casting every time.

In order to ensure the sealing performance during smelting and avoid blockage during melt outflow, the ratio of the casting caliber of the casting head to the diameter of the smelting container is 1: 5-1: 15.

The mounting section and the fragmentation section of the casting head can be made of different materials or the same material, in order to reduce cost, the casting head is made of graphite, and the wall thickness of the mounting section is larger than that of the fragmentation section. The casting head made of the material in mass production has low cost, realizes different functions of the installation section and the fragmentation section through different wall thicknesses, and has simple structure and good effect.

For convenience of operation, the impact device preferably comprises an impact head and a cylinder connected with the impact head.

In order to adjust the cooling speed conveniently, cooling system is including being located cooling plate, the cooling plate on the movable platform are equipped with the water-cooling runner in, and the water inlet of water-cooling runner has the flow valve of regulation flow. The flow rate of the cooling water can be adjusted through a flow valve, so that the water temperature at the water outlet is 35-50 ℃.

For simple structure and convenient operation, it is preferable that the movable platform comprises a base plate, and a slide rail for mounting the base plate.

In order to prevent the blockage of the melt at the outlet, the induction heating wire of the heating temperature control device wraps the outer peripheral surface of the smelting container main body and the outer peripheral surface of the pouring gate.

In order to improve the wettability of the enhanced phase particles and facilitate the control of the feeding speed, the secondary feeding device comprises a secondary hopper, a screw feeder matched with the secondary hopper, and a resistance heating temperature control device matched with the secondary hopper.

Preferably, the stirring device comprises a stirring rod located in the middle of the smelting container and a motor for driving the stirring rod, the stirring rod is provided with a plurality of blade layers, the blade layers comprise a spiral blade layer and a prismatic blade layer, the prismatic blade layer comprises a plurality of prismatic blades arranged along the circumferential direction of the stirring rod, and the range of at least one internal angle of a cross-sectional polygon of the prismatic blades is 30-60 °.

The paddle layer of the stirring device structure comprises a spiral paddle layer and a prismatic paddle layer, and the spiral paddle layer can increase the downward-pressing flow of a melt, is beneficial to adding a reinforcing phase and promotes the dispersion of the reinforcing phase; the prismatic blade layer further provides transverse shearing force for the composite material melt, which is beneficial to crushing the reinforcing phase agglomerated particles, greatly improves the dispersion uniformity of the reinforcing phase particles, and can save the time required for dispersing the reinforcing phase particles. The edge of the prismatic blade layer forms a cutting angle, so that a good shearing effect is generated on the composite material melt, a good crushing effect is realized on the reinforcing phase agglomerated particles, and the cutting effect formed by the internal angle ranging from 30 degrees to 60 degrees is better.

A bottom casting method for preparing a particle-reinforced aluminum-based composite material, comprising the following steps:

(1) after pretreatment, the reinforced phase particles are put into a secondary feeding device for preheating;

(2) preparing and smelting an aluminum-based alloy: putting the ingredients into a smelting container according to the required aluminum alloy proportion, vacuumizing, introducing protective gas, and starting a heating temperature control device to completely melt the ingredients;

(3) addition of reinforcing phase particles:

opening the stirring device (4), and adding the reinforcing phase particles by using the secondary feeding device (3) when the temperature reaches a semi-solid state interval of 5-50 ℃ below a liquidus;

(4) particle homogenization of composite material melt:

after the reinforcing phase particles are added, controlling the temperature to be 0-40 ℃ below the liquidus, and stirring the mixture until the mixture is uniform;

(5) bottom casting:

in order to ensure the distribution uniformity of the reinforcing phase in the melt during casting, after heating to the casting temperature, the bottom casting is started with the stirring speed of 300-1500r/min, preferably 600-900 r/min. And (3) smashing the fragmentation section by using an impact device, enabling the fragment of the fragmentation section to fall into a waste residue groove, enabling the mold to contain a front uniform melt flowing out of a casting gate, simultaneously opening a cooling system to cool the mold, and adjusting the flow rate of cooling water by using a flow valve to enable the water temperature range of a water outlet to be 35-50 ℃. Observing the liquid level descending degree of the melt through an observation window, and when the adhesion degree of the melt flowing out from the pouring gate is increased, namely the front part of uniform melt flows out sufficiently, moving the movable platform to enable the waste residue groove to be arranged at the position of the pouring gate to contain the rear part of melt containing the slag;

(6) and (5) performing subsequent heat treatment.

Preferably, the pretreatment of step (1) comprises the following steps: washing the reinforced phase particles with water to be neutral after acid washing, then drying the particles at the temperature of 100-200 ℃, and then screening the particles to obtain the reinforced phase particles. The pretreatment process does not need high-temperature oxidation of reinforced phase particles in the prior art, saves energy consumption and shortens production period.

Preferably, the preheating temperature of the step (1) is 200-1000 ℃ to improve the wettability between the reinforcing phase and the melt.

In order to better promote the mixing of the reinforcing phase particles, preferably, the step (3) comprises the following steps:

stirring in the first stage: in order to make the components of the aluminum liquid uniform and remove the gas in the melt, the stirring device is opened to stir at a low speed with the rotating speed lower than 300r/min

Stirring in the second stage: when the temperature is reduced to a semi-solid state region of 0-40 ℃ below the liquidus, the stirring speed is increased to 300-1000r/min, so that a stirring vortex is formed on the surface of the melt, and the subsequently added reinforcing phase particles can enter the melt conveniently; after the formation of the stable vortex, a secondary feeding device was used to add the reinforcing phase particles to the center of the vortex.

In order to disperse the reinforcing phase particles uniformly, preferably, the step (4) includes the steps of:

semi-solid strong shearing and stirring: after the reinforcing phase particles are added, the temperature is controlled to be 0-40 ℃ below the liquidus line, the stirring rotating speed is further increased to 400-2000r/min, preferably 800-1000r/min, the high-speed strong shearing stirring is carried out for 0.5-4 hours, and the uniformity of the reinforcing particles in the aluminum matrix is effectively improved;

the semi-solid strong shearing and stirring in the step (4) has a remarkable effect of improving the wettability of the interface of the reinforced particles and the aluminum matrix, promotes the crushing of the agglomerated particles and improves the dispersion uniformity of the reinforced phase particles.

The utility model further divides the addition of the reinforced phase particles into two parts of (3) the addition of the reinforced phase particles and (4) the particle homogenization of the composite material melt, and the smooth addition of the reinforced phase particles is promoted by the lower pressure type flow field in the part (3) through the stirring design of two stages and enters the melt, thereby laying a foundation for the homogenization of the next step; the part (4) generates strong shearing action by high-speed stirring, particle agglomeration generated in the adding process in the step (2) is effectively broken up, and the uniformity of reinforcing phase particles in a melt is further increased; through the combination of the step (3) and the step (4), the addition and the uniform stirring of the enhanced phase particles are matched, and a uniform melt with higher content of the enhanced phase particles, uniform distribution, no defects of gas entrapment and the like is obtained. Therefore, the finally prepared composite material reinforcing phase particles are uniformly dispersed in the aluminum matrix, and the reinforcing phase particles are tightly combined with the interface of the aluminum matrix and have good wettability.

In order to adjust the structure size of the casting, the bottom casting in the step (5) can adjust the flow rate of cooling water through a flow valve, so that the water temperature at a water outlet is in a range of 35-50 ℃.

In order to ensure the uniformity of the composition and improve the performance, it is preferable that the step (6) of the subsequent heat treatment comprises the steps of: solution treatment is carried out for 6-9h at 510-540 ℃, and then aging treatment is carried out for 4-7h at 150-170 ℃.

Preferably, the step (2) specifically comprises the following steps: putting the aluminum alloy proportioning materials into a smelting container (2) according to the required aluminum alloy proportion, stopping vacuumizing after vacuumizing to 10-100Pa, filling inert gas protective gas to 200-800 Pa, heating to 700-800 ℃, and preserving heat for 0.5-2 hours to ensure that the materials are completely melted. The low vacuum of this step greatly shortens man-hour, improves production efficiency.

For better wear resistance and matching strength and ductility, the reinforcing phase particles of the present invention are preferably added in an amount of 5 to 30% by volume. Any micron-sized reinforcing phase particles can be selected, such as ceramic phases of silicon carbide, aluminum oxide, boron carbide, boron nitride, chromium oxide and the like, diamond, graphite and the like. For better wear resistance, silicon carbide is preferred. The particle size range of the reinforcing phase particles selected by the utility model is 5-30 μm, and the preferred particle size range of the reinforcing phase particles is 8-15 μm in order to realize uniform distribution of the particles and optimization of the performance.

The utility model can select any cast aluminum alloy substrate such as A356, A357, A359, A360, 2025, 6061 and the like, and in order to obtain better wear resistance, the preferred aluminum alloy substrate is A357 and A359.

Compared with the prior art, the utility model has the advantages that:

for this bottom casting device of the utility model:

1. the bottom casting device is a gravity casting device, has high casting efficiency, simple device and lower manufacturing cost;

2. the bottom casting device realizes the separation of the front part uniform melt and the rear part melt containing the slag by the arrangement of the movable platform, the mold and the slag groove under the protection of the protective gas in the furnace body. The air entrainment degree of the front part of the melt is light, the air holes are few, and the particles are uniformly distributed; the melt at the rear part has more entrainment and serious particle agglomeration. Therefore, the front part of the melt is selected, so that casting defects and particle agglomeration can be effectively reduced, uniform and compact castings can be obtained, and the casting performance of the composite material is improved;

3. the bottom casting is matched with the stirring device, the stirring is kept in the melt casting process, and the sedimentation of reinforced phase particles can be avoided, so that the integral uniformity of the melt is kept, and the performance deviation of different parts of the casting is reduced.

4. For the casting of the aluminum matrix composite, if various stopper-type and valve-type bottom pouring control is adopted, the following problems can be caused: when the stopper rod and the valve which are tightly matched move, the stopper rod and the valve are easy to rub against the crucible repeatedly to generate scraps and then are involved in flowing melt. Finally causing the pollution of the alloy and casting defects such as inclusion and the like; the precision requirement of the close fit at high temperature is high, the matched parts can be gradually lost due to repeated friction, the matching service life is short, and once the parts are lost, the melt leakage danger can be generated, so that the personal safety is influenced; thirdly, after the casting of each furnace is finished, more melt or reinforcing phase adheres to a pouring gate and a sealing element, such as a stopper rod, a valve and the like, due to the high viscosity characteristic of the composite material melt. These residues tend to contaminate the melt during the next furnace casting process and render the seal ineffective, thereby rendering bottom casting impractical.

The bottom casting of the bottom casting device is realized by breaking the fragmentation section of the casting head, and a new casting head can be replaced after each use, so that the sealing effectiveness and the safety can be ensured; the influence of adhesion of a melt or a reinforcing phase is prevented, the melt cast at the bottom of each furnace can be ensured to flow out stably without involving other pollutants, and the casting performance of the composite material is improved;

5. the waste slag groove is used, so that the effect of collecting the fragmentation section and the rear part of melt is achieved, the structure of the device is simplified, the cleaning is convenient, and the production efficiency is improved;

6. the cooling system is arranged at the bottom of the mold, so that directional solidification heat flow is generated, the pasty solidification trend is weakened, the phenomena of difficult feeding and the like caused by pasty solidification are reduced, and the solidification defects of shrinkage porosity, shrinkage cavity and the like are reduced.

7. The cooling system improves the cooling speed, effectively refines crystal grains and improves the performance of the casting. Meanwhile, the SiC and other reinforced phases are distributed in the primary phase crystal boundary in the solidification process, the cooling speed is improved, the crystal boundary is increased, the SiC and other reinforced phases can be better accommodated, and the SiC and other reinforced phases are uniformly distributed.

For this bottom casting method of the utility model:

1. the bottom casting device is adopted to realize the separation of the front part uniform melt and the rear part melt containing the slag, the gas entrainment degree of the front part melt is light, the air holes are few, and the particles are uniformly distributed; the melt at the rear part has more entrainment and serious particle agglomeration. Therefore, the front part of the melt is selected, so that casting defects and particle agglomeration can be effectively reduced, uniform and compact castings can be obtained, and the casting performance of the composite material is improved;

2. the bottom casting device is simple to operate, is convenient for operators to operate, and smoothly separates the front part melt from the rear part melt.

Drawings

Fig. 1 is a schematic view of the entire structure of a bottom casting apparatus according to an embodiment of the present invention;

FIG. 2 is a schematic structural view of a cooling plate according to an embodiment of the present invention;

FIG. 3 is a schematic structural view of a stirring rod according to an embodiment of the present invention;

FIG. 4 is a metallographic structure of an aluminum-based composite material according to an embodiment of the present invention;

FIG. 5 is a scanning electron microscope image of the reinforcement/aluminum matrix interface of the aluminum matrix composite according to the embodiment of the present invention.

Detailed Description

The following detailed description of embodiments of the present invention is provided in connection with the accompanying drawings and examples.

As shown in fig. 1-3, the bottom casting device for preparing the particle reinforced aluminum matrix composite comprises a furnace body 1, wherein a smelting container 2 is arranged in the furnace body 1, and a casting opening 21 with a melt flow channel is arranged at the bottom of the smelting container 2; the smelting container 2 is provided with a secondary feeding device 3, a heating temperature control device, a stirring device 4, a vacuumizing device 5, a thermocouple 6 for temperature measurement and a material smashing rod 7 in a matching manner.

A casting head 8 is arranged to be replaceable with the casting opening 21, the casting head 8 comprising a mounting section 81 for cooperating with the melt channel, and a breakable section 82; the furnace body 1 is internally provided with an impact device 9 for breaking the fragmentation section 82; the bottom of the furnace body 1 is provided with a movable platform 10, and the movable platform 10 is provided with a mold 101 and a waste residue groove 102; when the movable platform 10 is positioned at the first position, the waste residue groove 102 is used for containing the smashed fragmentation section 82, the mould 101 is used for containing the front part uniform melt flowing out from the casting head 8, and when the movable platform 10 is positioned at the second position, the waste residue groove 102 is used for containing the rear part melt containing the slag; a cooling system is provided on the movable platform 10 at a position corresponding to the bottom of the mold 101. The slag chute 102 of this embodiment has a flared opening.

For better heat preservation, the smelting vessel 2 is a graphite crucible.

In order to ensure sealing during melting and to ensure that no blockage occurs during outflow of the melt, the ratio of the diameter of the pouring opening 21 of the casting head 8 to the diameter of the melting vessel 2 is 1: 10. In order to facilitate the replacement and removal of the casting head 8, the mounting section 81 of the casting head 8 is an externally threaded section, which is in a mating connection with a corresponding internal thread of the melt channel. The mounting section 81 and the fragmentation section 82 of the casting head 8 can be made of different materials or the same material, in order to reduce the cost, the casting head 8 is made of graphite, and the wall thickness of the mounting section 81 is larger than that of the fragmentation section 82.

For ease of operation, the striking device 9 preferably comprises a striking head 91 and a cylinder 92 connected to the striking head 91.

In order to adjust the cooling speed conveniently, the cooling system includes the cooling plate 103 located on the movable platform 10, and the cooling plate 103 is provided with a water-cooling flow channel, a flow valve for adjusting the flow rate is provided at a water inlet of the water-cooling flow channel, and the water-cooling flow channel of the embodiment is arranged in an arch shape as shown in fig. 2. The flow rate of the cooling water can be adjusted through a flow valve, so that the water temperature at the water outlet is 35-50 ℃.

For simple structure and easy operation, the movable platform 10 includes a base plate, and a slide rail on which the base plate is mounted.

In order to prevent the melt at the outlet from being blocked, the heating wires of the first heating temperature control device wrap the outer peripheral surface of the main body of the smelting vessel 2 and the outer peripheral surface at the casting opening 21.

In order to make the particle addition more efficient and uniform, the secondary feeding device 3 of the present embodiment includes a secondary hopper 31, a screw feeder 32 disposed in cooperation with the secondary hopper 31, and a resistance heating temperature control device disposed in cooperation with the secondary hopper 31.

The stirring device 4 comprises a stirring rod 41 positioned in the middle of the smelting vessel 2 and a driving motor for driving the stirring rod 41, wherein a plurality of blade layers are arranged on the stirring rod 41, the blade layers comprise a spiral blade layer 42 and a prismatic blade layer 43, the prismatic blade layer 43 comprises a plurality of blade layers arranged along the circumferential direction of the stirring rod 41, and the cross-sectional polygon of the prismatic blade 431 has at least one interior angle in the range of 30-60 degrees. The stirring rod 41 of this embodiment is sequentially provided with three paddle layers, the first and third paddle layers are both spiral paddle layers 42, and the second paddle layer is prismatic paddle layer 43. The prismatic blade 431 has a shape of a right quadrangular prism including two inner corners of 30 ° and two inner corners of 150 °. The four prismatic type blades 431 are uniformly spaced on the same horizontal plane.

The bottom casting method for preparing the particle-reinforced aluminum-based composite material using the above bottom casting device comprises the steps of: the aluminum alloy matrix of the embodiment comprises the following components in percentage by weight: 1% of Mg, 10% of Si and the balance of Al; the reinforcing phase particles are: SiC particles, 20% by volume, having a particle size of 15 μm.

(1) Pretreatment of SiC particles: weighing SiC particles in proportion, cleaning the SiC particles for 24 hours by using a 5% HF solution, then washing the SiC particles to be neutral in an ultrasonic cleaner, placing the SiC particles in a box-type resistance furnace, preserving heat for 7 hours at the temperature of 170 ℃ for drying, sieving the dried powder by using a vibrating screen, placing the powder in a secondary hopper 31, preheating the powder, preserving heat for 200 ℃, and reserving the powder for later use.

(2) Preparing and smelting AlMgSi alloy: and (3) filling weighed pure Al, pure Mg and Al-Si intermediate alloy into the graphite crucible, starting a vacuumizing device 5 to vacuumize the furnace until the vacuum degree reaches 10-20Pa, stopping vacuumizing, and filling inert gas protective gas into the furnace until the vacuum degree reaches 300-400 Pa. And starting a heating temperature control device to heat to 750 ℃, and keeping the temperature for 0.5 hour to ensure that the melt in the crucible is completely melted.

(3) And adding SiC particles.

Stirring in the first stage: slag such as oxide skin on the surface of the melt is scraped by the material smashing rod 7, the stirring rod 41 is descended to the melt, and in order to ensure that the components of the melt are uniform and to remove the wrapped gas in the melt, the stirring device 4 carries out low-speed stirring at the rotating speed of less than 300r/min until the temperature is reduced to a semisolid interval of 0-20 ℃ below the liquidus.

Stirring in the second stage: the rotating speed of the stirring device 4 is increased to 400r/min, so that stirring vortexes are formed on the surface of the aluminum liquid, reinforcing phase particles are added to the centers of the vortexes through the spiral feeder 32, the feeding condition and the liquid level state are observed in real time through the observation window, the feeding speed is controlled, and the uniform feeding is ensured

(4) The particles of the composite melt are homogenized.

Semi-solid strong shearing and stirring: after the reinforcing phase particles are completely added, the temperature is controlled to be 0-20 ℃ below the liquidus line, the rotating speed of the stirring device 4 is increased to 900r/min, and the high-speed strong shearing stirring is carried out for 1-2 hours, so that the reinforcing phase particles are uniformly dispersed, and the interface wettability between the aluminum matrix and the reinforcing phase particles is effectively enhanced.

(5) Bottom casting: in order to ensure the distribution uniformity of the reinforcing phase in the melt during casting, the bottom casting is carried out after the melt is heated to the casting temperature and the stirring speed of 800r/min is kept. The impact device 9 is used for smashing the fragmentation section 82, the fragments of the fragmentation section 82 fall into a waste residue groove 102, the mold 101 is used for containing front uniform melt flowing out of the casting opening 21, meanwhile, a cooling system is opened for cooling the mold 101, and the flow valve is used for adjusting the flow of cooling water to enable the water temperature range of the water outlet to be 40 ℃. Observing the liquid level descending degree of the melt through an observation window, moving the movable platform 10 when the adhesion degree of the flowing liquid is increased, namely the front part uniform melt flows out sufficiently, so that the waste slag groove 102 is arranged at the position of the casting opening 21 and is used for containing the rear part melt containing the slag and flowing out from the casting opening 21;

(6) and (3) subsequent heat treatment:

the obtained ingot was subjected to solution treatment at 538 ℃ for 8 hours and aging treatment at 160 ℃ for 5 hours.

The metallographic structure of the aluminum matrix composite material manufactured by the utility model is shown in figure 4, and the figure shows that the prepared aluminum matrix composite material SiC is uniformly dispersed, no SiC agglomeration and casting defect exist, and the SiC/Al interface is tightly combined.

FIG. 5 is a scanning electron microscope image of the aluminum matrix interface of the aluminum matrix composite material manufactured by the present invention，The graph shows that the prepared aluminum matrix composite material SiC is uniformly dispersed, and the SiC/Al interface is tightly combined.

The technical means disclosed in the utility model scheme are not limited to the technical means disclosed in the above embodiments, but also include the technical scheme formed by any combination of the above technical features. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principle of the present invention, and such improvements and modifications are also considered to be within the scope of the present invention.

Claims (6)

1. The bottom casting device for preparing the particle reinforced aluminum matrix composite comprises a furnace body (1), wherein a smelting container (2) is arranged in the furnace body (1), and a casting opening (21) with a melt flow channel is formed in the bottom of the smelting container (2); with smelting container (2) cooperation is equipped with secondary feeding device (3), heating temperature regulating device, agitating unit (4), its characterized in that: -a casting head (8) is exchangeably arranged with the casting opening (21), the casting head (8) comprising a mounting section (81) for cooperation with the melt channel, and a frangible fracture section (82); an impact device (9) for breaking the fragmentation section (82) is arranged in the furnace body (1); the bottom of the furnace body (1) is provided with a movable platform (10), and the movable platform (10) is provided with a mold (101) and a waste residue groove (102); when the movable platform (10) is located at a first position, the waste slag groove (102) is used for containing the smashed fragmentation section (82), the mould (101) is used for containing the front part of uniform melt flowing out of the casting head (8), and when the movable platform (10) is located at a second position, the waste slag groove (102) is used for containing the rear part of melt containing slag; and a cooling system is arranged on the position of the movable platform (10) corresponding to the bottom of the mould (101).

2. The bottom casting apparatus for producing a particle-reinforced aluminum-based composite material as claimed in claim 1, wherein: the mounting section (81) of the casting head (8) is an external thread section, so as to be connected in a matching manner with a corresponding internal thread of the melt channel.

3. The bottom casting apparatus for producing a particle-reinforced aluminum-based composite material as claimed in claim 2, wherein: the ratio of the diameter of a casting opening (21) of the casting head (8) to the diameter of the smelting container (2) is 1: 5-1: 15.

4. The bottom casting apparatus for producing a particle-reinforced aluminum-based composite material as claimed in claim 2, wherein: the casting head (8) is made of graphite, and the wall thickness of the mounting section (81) is larger than that of the fragmentation section (82).

5. The bottom casting apparatus for producing a particle-reinforced aluminum-based composite material as claimed in claim 1, wherein: the impact device (9) comprises an impact head (91) and a cylinder (92) connected with the impact head (91).

6. The bottom casting apparatus for producing a particle-reinforced aluminum-based composite material as claimed in any one of claims 1 to 5, wherein: the stirring device (4) comprises a stirring rod (41) located in the middle of the smelting container (2) and a driving motor used for driving the stirring rod (41), wherein a plurality of layers of blade layers are arranged on the stirring rod (41), the stirring rod comprises a spiral blade layer (42) and a prismatic blade layer (43), the prismatic blade layer (43) comprises a plurality of prismatic blades (431) arranged along the circumferential direction of the stirring rod (41), and the range of at least one internal angle of the cross-section polygon of each prismatic blade (431) is 30-60 degrees.

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