Aluminum alloy semi-solid slurry preparation device, die-casting equipment and die-casting process

Abstract

The invention relates to the technical field of aluminum alloy casting, and provides an aluminum alloy semi-solid slurry preparation device, die-casting equipment and a die-casting process. The nitrogen supply device transports nitrogen to a stirring device, and a motor in the stirring device drives a connecting rod, a fan blade disk and a rotor to rotate to achieve rotational stirring. At the same time, the nitrogen is blown into the cavity of the rotor through the rotation of the fan blade disk and blown through a blowing hole. Stirring and blowing are combined to achieve rapid preparation of the aluminum alloy semi-solid slurry, so that the aluminum alloy semi-solid slurry can be quickly prepared in the die-casting production process of the aluminum alloy casting, and the content of defects such as pores and shrinkage cavities inside the high-pressure casting is effectively reduced or eliminated, and the problem of internal defects of the casting is solved.

Description

Technical Field

[0001] The present application relates to the technical field of aluminum alloy casting, and in particular to an aluminum alloy semi-solid slurry preparation device, die-casting equipment and die-casting process. Background Art

[0002] As the automotive industry's requirements for lightweight, green environmental protection, energy conservation and emission reduction become increasingly stringent, automotive aluminum casting parts, especially high-pressure casting business, are developing rapidly, the product coverage is increasing, and it is still developing rapidly at an alarming rate. At present, due to the inevitable air entrainment phenomenon, aluminum alloy solidification shrinkage and untimely micro-dendritic seepage shrinkage in the conventional liquid high-pressure casting process, the quality problems such as internal pores, macro and micro shrinkage cavities that often appear in the production process have become a problem that needs to be solved urgently in the field of high-pressure casting. Summary of the invention

[0003] The embodiments of the present application provide an aluminum alloy semi-solid slurry preparation device, die-casting equipment and die-casting process, which can effectively solve the problems in the background technology.

[0004] To achieve the above object, the present invention provides the following technical solutions:

[0005] In the first aspect, a device for preparing a semi-solid slurry of an aluminum alloy is provided, comprising a nitrogen supply device and a stirring device, wherein the stirring device comprises a box body, a sealing baffle, a motor, a connecting rod, a fan blade disk, and a rotor, wherein a sealing baffle is arranged in the box body, and the sealing baffle divides the box body into an upper box body and a lower box body, and a connecting rod is arranged in the upper box body, and the connecting rod can be driven to rotate by the motor; a fan blade disk is arranged in the lower box body, and the fan blade disk comprises an upper connecting disk, a fan blade, and a lower connecting disk, and at least two fan blades are fixedly arranged between the upper connecting disk and the lower connecting disk, and the fan blades are inclined in the same direction at the same angle, and the upper connecting disk is fixedly connected to the connecting rod; the rotor is a hollow cylinder, with an opening at the upper end and a closing at the lower end, and a plurality of rows of blowing holes are evenly arranged around the upper edge of the lower section of the rotor; the rotor is fixedly connected to the lower connecting disk, and a circular hole is opened in the middle of the lower connecting disk, and the circular hole is connected to the cavity of the rotor; an air inlet is arranged on the lower box body, and the nitrogen supply device is connected to the air inlet through a vent pipe.

[0006] In some embodiments, it also includes a driven gear and a motor gear, the connecting rod is fixed at the center of the driven gear, the output shaft of the motor is fixed at the center of the motor gear, and the motor gear is vertically meshed with the driven gear.

[0007] In some embodiments, the nitrogen supply equipment includes a nitrogen tank, which is connected to the air inlet through a ventilation pipe, and the ventilation pipe is provided with a flow meter and a pressure gauge; the flow meter is used to display the air flow in the ventilation pipe; the pressure gauge is used to display the nitrogen pressure in the ventilation pipe.

[0008] In some embodiments, a bracket is further included for mounting the stirring device.

[0009] In some embodiments, a control panel is also included, which is electrically connected to the motor and is used to control the switch and speed of the motor.

[0010] In the second aspect, an embodiment of the present application provides a die-casting device for aluminum alloy castings, including a holding furnace, a ladling machine, a die-casting machine, and a casting mold; the die-casting machine includes a punch and a pressure chamber, the ladling machine includes a ladling spoon, and the ladling spoon is used to transport the aluminum liquid from the holding furnace to the pressure chamber of the die-casting machine; and also includes the aluminum alloy semi-solid slurry preparation device described in any of the above embodiments.

[0011] In a third aspect, an embodiment of the present application provides a die-casting process for aluminum alloy castings, which is applied to a die-casting equipment for aluminum alloy castings described in any of the above embodiments, and includes the following steps: a spoon scoops up aluminum alloy liquid from a holding furnace and transports the molten aluminum to the bottom of a rotor of the aluminum alloy semi-solid slurry preparation device; the rotor physically stirs the aluminum alloy liquid by rotating, and nitrogen is blown into the aluminum liquid through the blowing holes in the lower section of the rotor for gas phase induction to prepare an aluminum alloy semi-solid slurry; after the preparation of the aluminum alloy semi-solid slurry is completed, the spoon continues to move forward to pour the aluminum alloy semi-solid slurry into the pressing chamber.

[0012] In some embodiments, the rotor is stirred at a speed of 2-3 rpm, while nitrogen is introduced at a flow rate of 45-50 L / min for a duration of 5 s.

[0013] In some embodiments, the aluminum alloy semi-solid slurry is a low-solid mixed aluminum alloy slurry in which the solid phase microstructure is granular and the solid phase component is 10±1vt%.

[0014] In some embodiments, the steps are also included: the temperature of the aluminum alloy liquid in the insulation furnace is controlled at 625±5°C, and the prepared aluminum alloy semi-solid slurry is a low-solid mixed aluminum alloy slurry with a solid phase micromorphology of granular and a solid phase component of 10±1vt%; the surface temperature of the mold cavity of the casting mold is ensured to be 200°C-240°C; from the time when the aluminum liquid is poured into the pressure chamber to the time when the aluminum liquid reaches the inner gate of the casting mold, it is a slow injection stage with a slow injection speed of 0.3-0.4m / s, and after the aluminum liquid enters the inner gate, it switches to a high-speed injection stage with a high-speed injection speed of 4.8-5m / s, until the pressure rises to a holding pressure of 1160±5bar, and the pressure is maintained for 10s; after the pressure maintenance ends, the die-casting machine leaves the mold to cool for 7-8s.

[0015] Compared with the prior art, the present invention has the following beneficial effects:

[0016] The present invention provides an aluminum alloy semi-solid slurry preparation device, die-casting equipment and die-casting process, wherein the nitrogen supply device delivers nitrogen to the stirring device, and the motor in the stirring device drives the connecting rod, the fan disk and the rotor to rotate to achieve rotational stirring, and at the same time, the nitrogen is blown into the cavity of the rotor through the rotation of the fan disk and blown through the blowing hole, thereby combining stirring and blowing to achieve rapid preparation of aluminum alloy semi-solid slurry, thereby in the die-casting production process of aluminum alloy castings: (1) Since the aluminum liquid contains solid phase components, its viscosity is high and it is not easy to produce (1) The solidification shrinkage rate of aluminum alloy slurry containing solid phase components is much smaller than that of pure aluminum liquid, which reduces the possibility of shrinkage cavities; (2) After physical stirring and gas phase induction, the solid phase components in the aluminum liquid exist in the form of suspended spherical particles. This microscopic morphology can provide more nucleation sites during the solidification process, refine the grains, reduce the frequency of microscopic holes after the closed growth of the dendrite skeleton, and reduce the risk of microscopic shrinkage cavities caused by untimely seepage and shrinkage compensation between dendrites. The semi-solid aluminum alloy slurry preparation device, die-casting equipment and die-casting process of the present application can realize the rapid preparation of semi-solid aluminum alloy slurry, effectively reduce or eliminate the content of defects such as pores, macroscopic shrinkage cavities and microscopic shrinkage cavities inside high-pressure castings, and solve the problem of internal defects in castings. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0018] Figure 1 It is a structural schematic diagram of a device for preparing semi-solid slurry of aluminum alloy in the present application.

[0019] Figure 2 This is a schematic diagram of the partial structure of a stirring device of an aluminum alloy semi-solid slurry preparation device of the present application.

[0020] Figure 3 It is a schematic diagram of a die-casting process flow of an aluminum alloy casting in the present application.

[0021] Among them: 1- bracket, 2- box body, 3- sealing baffle, 4- upper box body, 5- lower box body, 6- motor, 7- driven gear, 8- motor gear, 9- connecting rod, 10- fan blade disk, 11- upper connecting disk, 12- fan blade, 13- lower connecting disk, 14- rotor, 15- blowing hole, 16- control panel, 17- air inlet, 18- nitrogen tank, 19- flow meter, 20- pressure gauge, 21- ventilation pipe, 22- sealing cover, 23- insulation furnace, 24- material spoon, 25- punch, 26- pressing chamber. DETAILED DESCRIPTION

[0022] The terms "first", "second", "third" and "fourth" etc. in the specification and claims of the present application and the drawings are used to distinguish different objects, rather than to describe a specific order. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device that includes a series of steps or units is not limited to the listed steps or units, but optionally includes steps or units that are not listed, or optionally includes other steps or units inherent to these processes, methods, products or devices.

[0023] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present application. The appearance of the phrase in various locations in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0024] The present invention has found that the sources of internal defects in high-pressure castings mainly include: (1) Due to the complex shape of high-pressure castings and the high injection speed, after the pouring process generates turbulence, gas will be trapped in the aluminum alloy to form pores; (2) The aluminum alloy will shrink during the solidification process, and the shrinkage rate is about 0.6%. Therefore, during the solidification process, shrinkage holes will be generated in the thick parts of the casting; (3) During the solidification process of liquid aluminum alloy, after the dendrite skeletons close and grow at the solidification front, microscopic holes will be formed between the dendrites. In the casting parts with large temperature gradients and cooling rates, the dendrite seepage compensation cannot play a role in time, resulting in microscopic shrinkage holes. In order to reduce or eliminate the risks of pores, macro shrinkage holes and micro shrinkage hole defects inside aluminum alloy high-pressure casting products, ensure product quality and improve production efficiency, an aluminum alloy semi-solid slurry preparation device is provided in one embodiment of the present application, including a nitrogen supply device and a stirring device, the stirring device including a box body, a sealing baffle, a motor, a connecting rod, a fan blade disk, and a rotor, a sealing baffle is provided in the box body, and the sealing baffle divides the box body into an upper box body and a lower box body, a connecting rod is provided in the upper box body, and the connecting rod can be driven to rotate by the motor; a fan blade disk is provided in the lower box body, and the fan blade disk The blade disk includes an upper connecting disk, blades, and a lower connecting disk. At least two blades are fixedly arranged between the upper connecting disk and the lower connecting disk. The blades are inclined at the same angle and in the same direction. The upper connecting disk is fixedly connected to the connecting rod. The rotor is a hollow cylinder with an opening at the upper end and a closed lower end. A plurality of rows of blowing holes are evenly arranged around the upper edge of the lower section of the rotor. The rotor is fixedly connected to the lower connecting disk. A circular hole is arranged in the middle of the lower connecting disk, and the circular hole is connected to the cavity of the rotor. An air inlet is arranged on the lower box body, and the nitrogen supply device is connected to the air inlet through a vent pipe. The nitrogen supply device described in this embodiment transports nitrogen to the stirring device, and the motor in the stirring device drives the connecting rod, the fan disk, and the rotor to rotate to achieve rotational stirring. At the same time, the nitrogen is blown into the cavity of the rotor through the rotation of the fan disk to achieve blowing through the blowing holes. The stirring and blowing are combined to achieve rapid preparation of aluminum alloy semi-solid slurry, and provide low-solid aluminum alloy semi-solid slurry for high-pressure casting (for example, low-solid aluminum alloy with a solid content of only 10±1%), thereby effectively reducing or eliminating the content of defects such as pores and shrinkage cavities inside high-pressure castings, and solving the problem of internal defects of castings.

[0025] In another embodiment of the present application, a die-casting device for aluminum alloy castings is provided, including a holding furnace, a ladling machine, a die-casting machine, and a casting mold; the die-casting machine includes a punch and a pressure chamber, the ladling machine includes a ladling spoon, and the ladling spoon is used to transport the aluminum liquid from the holding furnace to the pressure chamber of the die-casting machine; and it also includes the aluminum alloy semi-solid slurry preparation device described in any of the above embodiments.

[0026] In another embodiment of the present application, a die-casting process for aluminum alloy castings is provided, which is applied to a die-casting equipment for aluminum alloy castings described in any of the above embodiments, and includes the following steps: a spoon scoops up aluminum alloy liquid from a holding furnace and transports the molten aluminum to the bottom of a rotor of the aluminum alloy semi-solid slurry preparation device; the rotor physically stirs the aluminum alloy liquid by rotating, and nitrogen is blown into the aluminum liquid through the blowing holes in the lower section of the rotor for gas phase induction to prepare the aluminum alloy semi-solid slurry; after the preparation of the aluminum alloy semi-solid slurry is completed, the spoon continues to move forward to pour the aluminum alloy semi-solid slurry into the pressing chamber.

[0027] The embodiments of the present application can effectively reduce or eliminate the content of defects such as pores, macro shrinkage cavities and micro shrinkage cavities inside high-pressure castings during the die-casting production process of aluminum alloy castings, thereby solving the problem of internal defects in castings: (1) Since the aluminum liquid contains solid phase components, its viscosity is high and it is not easy to produce turbulent air entrainment, thereby greatly reducing the risk of pore generation; (2) The solidification shrinkage rate of the aluminum alloy slurry containing 10vt% solid phase components is much smaller than the shrinkage rate of pure aluminum liquid, reducing the possibility of shrinkage cavities; (3) After physical stirring and gas phase induction, the solid phase components in the aluminum liquid exist in the form of suspended spherical particles. This microscopic morphology can provide more nucleation sites during the solidification process, refine the grains, reduce the frequency of microscopic holes after the closed growth of the dendrite skeleton, and reduce the risk of microscopic shrinkage cavities.

[0028] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0029] Embodiment 1:

[0030] Embodiment 1 discloses a device for preparing semi-solid aluminum alloy slurry, such as Figure 1-2 As shown in the figure, it includes a bracket 1, a nitrogen supply device and a stirring device, and the bracket 1 is used to install the stirring device. The stirring device includes a box body 2, a sealing baffle 3, a motor 6, a driven gear 7, a motor gear 8, a connecting rod 9, a fan blade disk 10, a rotor 14, and a control panel 16. The sealing baffle 3 is set in the box body 2, and the sealing baffle 3 divides the box body 2 into an upper box body 4 and a lower box body 5. The connecting rod 9 is set in the upper box body 4, as shown in the figure. Figure 2As shown in , the upper part of the connecting rod 9 is rotatably fixed on the top surface of the box body 2 (for example, through a bearing), and the lower part of the connecting rod 9 is rotatably fixed on the sealing baffle 3. The connecting rod 9 is fixed at the center of the driven gear 7, and the output shaft of the motor 6 is fixed at the center of the motor gear 8. The motor gear 8 is vertically meshed with the driven gear 7, so that the connecting rod 9 can be driven to rotate by the motor 6. The control panel 16 is electrically connected to the motor 6 and is used to control the switch and speed of the motor 6.

[0031] The lower box body 5 is provided with a blade disc 10, and the blade disc 10 includes an upper connecting disc 11, blades 12, and a lower connecting disc 13. At least two blades 12 are fixedly arranged between the upper connecting disc 11 and the lower connecting disc 13. The blades 12 are inclined at the same angle and in the same direction. The blades may be sickle-shaped, trapezoidal, folded edge-shaped, etc. The upper connecting disc 11 is fixedly connected to the connecting rod 9.

[0032] The rotor 14 is a hollow cylinder with an open upper end and a closed lower end. Multiple rows of blowing holes 15 are evenly arranged around the upper edge of the lower section of the rotor 14. The rotor 14 is fixedly connected to the lower connecting plate 13. A circular hole is arranged in the middle of the lower connecting plate 13, and the circular hole is connected to the cavity of the rotor 14. A funnel-shaped sealing cover 22 is also sleeved on the upper end of the rotor 14. The sealing cover 22 is fixed to the bottom of the box 2. The sealing cover 22 is used to seal the connection of the rotor 14 to ensure that nitrogen is blown out from the cavity of the rotor 14 through the blowing holes 15.

[0033] The lower box 5 is provided with an air inlet 17, and the nitrogen supply device is connected to the air inlet 17 through a vent pipe 21. The nitrogen supply device includes a nitrogen tank 18, and the nitrogen tank 18 is connected to the air inlet 17 through a vent pipe 21. The vent pipe 21 is provided with a flow meter 19 and a pressure gauge 20. The flow meter 18 is used to display the gas flow in the vent pipe. The pressure gauge 20 is used to display the nitrogen pressure in the vent pipe.

[0034] The nitrogen supply device described in this embodiment 1 transports nitrogen to the stirring device, and the motor in the stirring device drives the connecting rod, the fan disk, and the rotor to rotate to achieve rotational stirring. At the same time, the nitrogen is blown into the cavity of the rotor through the rotation of the fan disk and blown through the blowing holes. The stirring and blowing are combined into one, which can realize the rapid preparation of aluminum alloy semi-solid slurry and provide low-solid aluminum alloy semi-solid slurry for high-pressure casting (for example, low-solid aluminum alloy with a solid content of only 10±1%), thereby effectively reducing or eliminating the content of defects such as pores and shrinkage cavities inside the high-pressure casting, and solving the problem of internal defects of the casting.

[0035] Embodiment 2:

[0036] In Example 2, a die-casting device for aluminum alloy castings is provided, comprising a holding furnace 23, a ladling machine, a die-casting machine, a casting mold, and also comprising the aluminum alloy semi-solid slurry preparation device as described in Example 1. The die-casting machine comprises a punch 25 and a pressure chamber 26. The ladling machine comprises a ladle 24, and the ladle 24 is used to transport the aluminum liquid from the holding furnace 23 to the pressure chamber 26 of the die-casting machine.

[0037] The die-casting process of an aluminum alloy casting of a die-casting device for an aluminum alloy casting described in this embodiment 2 includes the following steps: Figure 3 As shown in: the temperature of the aluminum alloy liquid in the insulation furnace is set and controlled to 625±5°C, the aluminum alloy liquid is scooped from the insulation furnace by a material spoon and transported to the bottom of the rotor of the aluminum alloy semi-solid slurry preparation device; the rotor physically stirs the aluminum alloy liquid by rotating, and nitrogen is blown into the aluminum liquid through the blowing holes in the lower section of the rotor for gas phase mutation, and the aluminum alloy semi-solid slurry is prepared by physical stirring and gas mutation (in one embodiment of this step, the rotor is stirred at a speed of 2-3 rpm, and nitrogen is introduced at a flow rate of 45-50L / min for a duration of 5S, and the prepared aluminum alloy semi-solid slurry is a low-solid mixed aluminum alloy slurry with a solid phase microscopic morphology of granular and a solid phase component of 10vt %); the prepared aluminum alloy semi-solid slurry is granular and has a solid phase component of 10±1vt % low solid phase mixed aluminum alloy slurry; after the preparation of the aluminum alloy semi-solid slurry is completed, the material spoon continues to move forward to pour the aluminum alloy semi-solid slurry into the pressure chamber; ensure that the surface temperature of the mold cavity of the casting mold is 200℃-240℃; from the time when the aluminum liquid is poured into the pressure chamber to the time when the aluminum liquid reaches the gate of the casting mold, it is a slow injection stage with a slow injection speed of 0.3-0.4m / s. After the aluminum liquid enters the gate, it switches to a high-speed injection stage with a high-speed injection speed of 4.8-5m / s, until the pressure rises to a holding pressure of 1160±5bar, and the pressure is maintained for 10s; after the pressure maintenance is completed, the die-casting machine leaves the mold to cool for 7-8s.

[0038] In the present embodiment 2, a slow injection stage and a high-speed injection stage are set in the casting process to shorten the filling time and reduce the heat loss of the mixture. At the same time, the solid-liquid mixed slurry is not easy to produce turbulent air entrainment, and the filling is smooth. Since the pouring temperature of low-solid phase die casting is much lower than that of conventional liquid die casting, the condensation sequence of aluminum alloy is shortened, and the solidification volume shrinkage rate is greatly reduced, thereby avoiding the occurrence of shrinkage cavities. Therefore, the mold cooling time of the die-casting machine is reduced to 7-8s to improve the production efficiency of castings. The die-casting equipment and die-casting process of an aluminum alloy casting provided in the present embodiment 2 reduce or eliminate the risk of pores and shrinkage defects inside aluminum alloy high-pressure casting products, ensure product quality, and improve production efficiency. Specifically manifested as follows:

[0039] (1) The solid-liquid mixed aluminum material is filled smoothly, without turbulent air entrainment, and the formation of pores is eliminated;

[0040] (2) Compared with the pouring temperature of 660-670℃ in liquid die casting, the material temperature of this method is only 625±5℃, which reduces the volume shrinkage rate, avoids the appearance of shrinkage holes, eliminates the internal stress caused by dendrite overlap, and reduces the tendency of casting thermal cracking;

[0041] (3) The dendrite morphology of the primary phase of aluminum alloy is broken, and the obtained granular micro-solid phase components provide more nucleation sites and are conducive to intergranular seepage and shrinkage compensation;

[0042] (4) Reduce the cooling sequence time, thereby reducing the casting cycle time and improving the casting production effect.

[0043] The embodiments of the present application are introduced in detail above. Specific examples are used in this article to illustrate the principles and implementation methods of the present application. The description of the above embodiments is only used to help understand the method and core idea of ​​the present application. At the same time, for general technical personnel in this field, according to the idea of ​​the present application, there will be changes in the specific implementation method and application scope. In summary, the content of this specification should not be understood as a limitation on the present application.

Claims

1. A device for preparing semi-solid aluminum alloy slurry, characterized in that: It includes a nitrogen supply device and a stirring device, wherein the stirring device includes a box, a sealing baffle, a motor, a connecting rod, a fan blade disk, and a rotor. The box is provided with a sealing baffle, and the sealing baffle divides the box into an upper box and a lower box. The upper box is provided with a connecting rod, and the connecting rod can be driven to rotate by the motor; The lower box body is provided with a fan blade disk, the fan blade disk comprises an upper connecting disk, a fan blade, and a lower connecting disk, at least two fan blades are fixedly arranged between the upper connecting disk and the lower connecting disk, the fan blades are inclined in the same direction at the same angle, and the upper connecting disk is fixedly connected to the connecting rod; The rotor is a hollow cylinder with an open upper end and a closed lower end. Multiple rows of blowing holes are evenly arranged around the upper edge of the lower section of the rotor. The rotor is fixedly connected to the lower connecting plate. A circular hole is arranged in the middle of the lower connecting plate, and the circular hole is connected to the cavity of the rotor. The lower box body is provided with an air inlet hole, and the nitrogen supply device is connected with the air inlet hole through a vent pipe; the device also includes a driven gear and a motor gear, the connecting rod is fixed at the center of the driven gear, the output shaft of the motor is fixed at the center of the motor gear, and the motor gear is vertically meshed with the driven gear; The nitrogen supply equipment comprises a nitrogen tank, which is connected to the air inlet through a ventilation pipe. A flow meter and a pressure gauge are provided on the ventilation pipe; the flow meter is used to display the air flow in the ventilation pipe; and the pressure gauge is used to display the nitrogen pressure in the ventilation pipe.

2. The device for preparing semi-solid aluminum alloy slurry according to claim 1, characterized in that: Also included is a bracket for installing the stirring device.

3. The device for preparing semi-solid aluminum alloy slurry according to claim 1, characterized in that: It also includes a control panel, which is electrically connected to the motor and is used to control the switch and rotation speed of the motor.

4. A die-casting device for aluminum alloy castings, characterized in that: It includes a holding furnace, a ladling machine, a die-casting machine, and a casting mold; the die-casting machine includes a punch and a pressure chamber, the ladling machine includes a ladle, and the ladle is used to transport aluminum liquid from the holding furnace to the pressure chamber of the die-casting machine; it also includes an aluminum alloy semi-solid slurry preparation device as described in any one of claims 1 to 3.

5. A die-casting process for aluminum alloy castings, applied to the die-casting equipment for aluminum alloy castings as claimed in claim 4, characterized in that: The steps include: The scoop takes the aluminum alloy liquid from the holding furnace and transports it to the bottom of the rotor of the aluminum alloy semi-solid slurry preparation device; The rotor physically stirs the aluminum alloy liquid by rotating, and nitrogen is blown into the aluminum liquid through the blowing holes in the lower section of the rotor to perform gas phase mutation to prepare aluminum alloy semi-solid slurry; After the aluminum alloy semi-solid slurry is prepared, the scoop continues to move forward to pour the aluminum alloy semi-solid slurry into the pressing chamber.

6. A die-casting process for aluminum alloy castings according to claim 5, characterized in that: The rotor was stirred at a speed of 2-3 rpm, and nitrogen was introduced at a flow rate of 45-50 L / min for 5 s.

7. A die-casting process for aluminum alloy castings according to claim 6, characterized in that: The aluminum alloy semi-solid slurry is a low-solid phase mixed aluminum alloy slurry whose solid phase microstructure is granular and whose solid phase component is 10±1vt%.

8. A die-casting process for aluminum alloy castings according to claim 7, characterized in that: The process also includes the following steps: the temperature of the aluminum alloy liquid in the holding furnace is controlled at 625±5°C, and the prepared aluminum alloy semi-solid slurry is a low-solid mixed aluminum alloy slurry with a solid phase microstructure of granular and a solid phase component of 10±1vt%; the surface temperature of the mold cavity of the casting mold is ensured to be 200°C-240°C; from the time when the aluminum liquid is poured into the pressure chamber to the time when the aluminum liquid reaches the inner gate of the casting mold, it is a slow injection stage, and the slow injection speed is 0.3-0.4m / s; after the aluminum liquid enters the inner gate, it is switched to a high-speed injection stage, and the high-speed injection speed is 4.8-5m / s, until the pressure rises to a holding pressure of 1160±5bar, and the pressure is maintained for 10s; After the pressure holding is completed, the die casting machine leaves the mold to cool for 7-8 seconds.

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