Magnesium alloy semi-solid die-casting forming equipment

Abstract

The invention discloses magnesium alloy semi-solid die-casting forming equipment which comprises a slurry supply device, a die-casting device and a forming die with a forming cavity, and slurry is supplied to a press-fitting device through the slurry supply device and then pressed into the forming cavity through the die-casting device to form a required magnesium alloy product. The device is characterized in that the slurry supply device comprises a slurry preparation mechanism and a quantitative supply mechanism, the slurry preparation mechanism and the die-casting device are connected in a sealed mode through the quantitative supply mechanism, and the slurry preparation mechanism is used for preparing solid raw materials into semi-solid magnesium alloy slurry; semi-solid magnesium alloy slurry prepared by the slurry preparation mechanism is quantitatively supplied to the die casting device through the quantitative supply mechanism. The device has the advantages that the structure is simple, and magnesium alloy products with excellent mechanical properties can be conveniently manufactured.

Description

Technical Field

[0001] The present invention relates to a die-casting device for magnesium alloy products, in particular to a semi-solid die-casting device for magnesium alloy products. Background Art

[0002] Magnesium alloy is a lightweight alloy with characteristics such as low density and high specific strength. Its heat dissipation and thermal stability are better than those of aluminum alloy. It is a new type of light alloy material with great development prospects. It is currently widely used in aerospace, 3C electronics, automobile manufacturing and other fields.

[0003] At present, the conventional method for the production and manufacturing of magnesium alloy products is die-casting: the relevant raw materials are placed in a furnace, melted first to form a liquid slurry, and then the liquid slurry is scooped into the injection chamber of the die-casting machine with a spoon, and finally the relevant magnesium alloy products are die-cast. In this method, first, the liquid slurry is scooped into the injection chamber with a spoon, and the metering accuracy is low, which will affect the accuracy of the product; secondly, the liquid slurry is exposed to the air, which is unsafe and causes a lot of heat loss. It may also cause the liquid slurry to be oxidized before entering the injection chamber of the die-casting machine, resulting in a higher porosity of the magnesium alloy product obtained by die-casting, which will reduce the strength of the product and lower the elongation. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a magnesium alloy semi-solid die-casting device which has a simple structure and is convenient for producing magnesium alloy products with relatively excellent mechanical properties.

[0005] The technical solution adopted by the present invention to solve the above technical problems is: A magnesium alloy semi-solid die-casting molding equipment includes a slurry supply device, a die-casting device and a molding die with a molding cavity. After the slurry is supplied to the press-fitting device by the slurry supply device, it is pressed into the molding cavity by the die-casting device to form the required magnesium alloy product. The slurry supply device includes a slurry preparation mechanism and a quantitative supply mechanism. The slurry preparation mechanism and the die-casting device are sealed and connected by the quantitative supply mechanism. The slurry preparation mechanism is used to prepare solid raw materials into semi-solid magnesium alloy slurry. The semi-solid magnesium alloy slurry prepared by the slurry preparation mechanism is quantitatively supplied to the die-casting device by the quantitative supply mechanism.

[0006] The slurry preparation mechanism includes a slurry preparation barrel with a feed hopper, a sealed slurry preparation chamber is provided in the slurry preparation barrel, the feed hopper is connected to the slurry preparation chamber, at least one mixing screw is provided in the slurry preparation chamber, and a heating mechanism for heating the slurry preparation chamber is provided on the outside of the slurry preparation barrel. The above-mentioned slurry preparation mechanism has a simple structure. Solid raw materials enter the slurry preparation chamber through the feed port. The raw materials are fully sheared and stirred by the screw. In combination with the heating mechanism provided on the outside of the slurry preparation barrel, a more uniform semi-solid slurry can be prepared. The prepared semi-solid slurry will not produce product branches, resulting in better performance of the product. According to the cycle and weight of the product, multiple sets of screws can be used for slurrying.

[0007] A heating rod is installed in the center of the mixing screw. Traditional screw structures basically conduct heat from the outside in, resulting in low temperatures inside the screw and uneven heat distribution. However, adding a heating rod in the center of the mixing screw allows heat to be conducted from the center outward, while also combining heat conduction from the outside inward, so that heat is evenly distributed throughout the screw, achieving better results in slurry preparation.

[0008] The slurry preparation cylinder is provided with an exhaust port connected to the slurry preparation chamber, and a one-way valve is provided in the exhaust port. The air in the slurry preparation cylinder is discharged through the exhaust port. The one-way valve allows the gas to be discharged but prevents the outside air from entering, thereby facilitating the exhaust and preventing the ingress of external air that could cause oxidation of the slurry.

[0009] The slurry preparation cylinder is provided with an air inlet connected to the slurry preparation chamber for introducing protective gas. A one-way valve is installed within the air inlet. After the gas within the slurry preparation cylinder is exhausted, protective gas is introduced through the air inlet to provide protection. Any remaining air within the slurry preparation cylinder must not mix with the protective gas, as this will affect the effectiveness of the protective gas.

[0010] A liquid level sensor is installed at the rear of the slurry preparation cylinder. The probe of the liquid level sensor extends into the slurry preparation chamber. The liquid level sensor is used to monitor the liquid position. When the probe of the liquid level sensor senses the liquid level, it means that the liquid level is full, and the mixing screw needs to stop running.

[0011] The quantitative supply mechanism is a quantitative pump. The feed hopper is connected to the upper part of the head end of the slurry preparation chamber. A discharge port is provided at the lower part of the tail end of the slurry preparation chamber. At least one storage barrel is sealed and connected to the discharge port. The die-casting device has an injection chamber. The die-casting device is provided with a feed port connected to the injection chamber. A one-way valve is provided in the feed port. The storage barrel and the feed port are sealed and connected via the quantitative pump. The feed hopper is provided at the head end of the slurry preparation chamber, and the discharge port is provided at the tail end of the slurry preparation chamber, which facilitates the slurry to be fully sheared and stirred by the screw. A storage barrel is provided at the discharge port. The volume of the storage barrel is designed to be larger than the maximum injection volume of the die-casting device. In combination with the one-way valve, the screw can be kept running to produce slurry, thereby improving efficiency. The quantitative supply mechanism is a quantitative pump with a simple structure and precise metering, which makes the product more precise. For products with large gram weight, multiple storage barrels can be connected in parallel to improve production efficiency.

[0012] The outside of the storage barrel is provided with an induction coil to prevent the slurry from cooling and to maintain the temperature. Since there is a lot of material in the storage barrel, when the machine is shut down and then restarted, the material in the storage barrel needs to be melted. The induction coil heats quickly and can quickly melt the slurry.

[0013] The die-casting device is provided with a heating device for heating the injection cavity on the outside, which keeps the slurry in the injection cavity warm and helps to ensure the performance of the product.

[0014] A pressure head is movably arranged in the injection cavity.

[0015] Compared with the existing technology, the advantages of the present invention are: simple structure, realization of full-process semi-solid continuous integrated production, the entire equipment integrates the mixing, compounding, slurry preparation and control, as well as the quantitative supply of slurry and die-casting of raw materials, forming a continuous and closed operation. From the production of raw materials to the product, the entire process is in a closed environment, the slurry will not oxidize, and the heat loss is also small. The production is safer and the metering is more accurate. There is no need to heat the raw materials to become liquid throughout the process, avoiding the risk of the chemical bonds inside the metal being destroyed after the raw materials are completely melted into liquid, affecting the performance of the raw materials. At the same time, the heating time is shortened, and it is more energy-saving and efficient. Compared with the products obtained by the traditional die-casting process, the strength of the magnesium alloy products finally obtained can be increased by 10% and the elongation can be increased by 50%. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a schematic cross-sectional view of the present invention; Figure 2 It is a schematic cross-sectional view of the present invention when the slurry is pressed into the forming cavity. DETAILED DESCRIPTION

[0017] The present invention will be described in further detail below with reference to the accompanying drawings and embodiments.

[0018] As shown in the figure, a semi-solid die-casting molding equipment for magnesium alloy includes a slurry supply device, a die-casting device 1 and a molding mold 2 with a molding cavity 21. After the slurry is supplied to the pressing device through the slurry supply device, it is pressed into the molding cavity 21 through the die-casting device 1 to form the required magnesium alloy product. The slurry supply device includes a slurry preparation mechanism 3 and a quantitative supply mechanism 4. The slurry preparation mechanism 3 and the die-casting device 1 are sealed and connected through the quantitative supply mechanism 4. The slurry preparation mechanism 3 is used to prepare solid raw materials into semi-solid magnesium alloy slurry. The semi-solid magnesium alloy slurry prepared by the slurry preparation mechanism 3 is quantitatively supplied to the die-casting device 1 through the quantitative supply mechanism 4.

[0019] In this specific embodiment, the slurry preparation mechanism 3 includes a slurry preparation barrel 301 with a feed hopper 31. A sealed slurry preparation chamber 32 is provided in the slurry preparation barrel 301. The feed hopper 31 is connected to the slurry preparation chamber 32. At least one mixing screw 33 is provided in the slurry preparation chamber 32. A heating mechanism 34 for heating the slurry preparation chamber 32 is provided on the outside of the slurry preparation barrel 301. The above-mentioned slurry preparation mechanism 3 has a simple structure. The solid raw material enters the slurry preparation chamber 32 through the feed port 12. The raw material is fully sheared and stirred by the screw. In combination with the heating mechanism 34 provided on the outside of the slurry preparation barrel 301, a more uniform semi-solid slurry can be prepared. The prepared semi-solid slurry will not produce product branches, resulting in better performance of the product. According to the cycle and weight of the product, multiple sets of screws can be used for slurrying.

[0020] In this embodiment, a heating rod 331 is provided at the center of the mixing screw 33. Conventional screws conduct heat from the outside in, resulting in excessively low temperatures inside the screw and uneven heat distribution. However, adding a heating rod 331 to the center of the mixing screw 33 allows heat to be conducted from the center outward, while also combining this with heat conduction from the outside inward. This allows heat to be evenly distributed throughout the screw, resulting in a better effect on slurry preparation.

[0021] In this embodiment, the slurry preparation cylinder 301 is provided with an exhaust port 35 connected to the slurry preparation chamber 32, and a one-way valve 36 is provided in the exhaust port 35. The air in the slurry preparation cylinder 301 is discharged to the outside through the exhaust port 35, and the one-way valve 36 allows the gas to be discharged to the outside without letting in the outside air, which is beneficial for exhaust and prevents the entry of external air and oxidation of the slurry.

[0022] In this embodiment, the slurry preparation cylinder 301 is provided with an air inlet 37 connected to the slurry preparation chamber 32 for introducing a protective gas. A one-way valve 30 is disposed within the air inlet 37. After the gas within the slurry preparation cylinder 301 is exhausted, the protective gas is introduced through the air inlet 37 to provide a protective effect. Any air remaining within the slurry preparation cylinder 301 cannot mix with the protective gas, as this would affect the effectiveness of the protective gas.

[0023] In this embodiment, a liquid level sensor 38 is provided at the rear end of the slurry preparation cylinder 301. The probe of the liquid level sensor 38 extends into the slurry preparation chamber 32. The liquid level sensor 38 is used to monitor the liquid position. When the probe head of the liquid level sensor 38 senses the liquid level, it indicates that the liquid level is full, and at this time, the mixing screw 33 needs to stop running.

[0024] In this specific embodiment, the quantitative supply mechanism 4 is a quantitative pump, the feed hopper 31 is connected and arranged at the upper part of the head end of the slurry preparation chamber 32, and a discharge port 39 is provided at the lower part of the tail end of the slurry preparation chamber 32. The discharge port 39 is sealed with at least one storage barrel 5, and the die-casting device 1 has an injection cavity 11. The die-casting device 1 is provided with a feed port 12 connected to the injection cavity 11, and a one-way valve 13 is provided in the feed port 12. The storage barrel 5 and the feed port 12 are sealed and connected through a quantitative pump. A feed hopper 31 is located at the head end of the slurry preparation chamber 32, and a discharge port 39 is located at the tail end of the chamber 32, facilitating sufficient shearing and stirring of the slurry by the screw. A storage barrel 5 is located above the discharge port 39. The volume of the storage barrel 5 is designed to be larger than the maximum injection volume of the die-casting device 1. In conjunction with a one-way valve 36, this allows the screw to continuously produce slurry, improving efficiency. The quantitative supply mechanism 4 is a quantitative pump with a simple structure and precise metering, resulting in higher product precision. For heavyweight products, multiple storage barrels 5 can be connected in parallel to improve production efficiency.

[0025] In this specific embodiment, a temperature control module 501 is provided on the lower discharge section of the storage barrel 5 .

[0026] In this embodiment, an induction coil 51 is provided outside the storage barrel 5 to prevent the slurry from cooling and maintain the temperature. Since there is a lot of material in the storage barrel 5, the material in the storage barrel 5 needs to be melted when the machine is restarted after shutdown. The induction coil 51 heats quickly and can quickly melt the slurry.

[0027] In this embodiment, a heating device 15 is provided outside the die-casting device 1 for heating the injection cavity 11. This device 15 keeps the slurry in the injection cavity 11 warm, which helps to ensure the performance of the product.

[0028] In this specific embodiment, a pressing head 16 is movably disposed in the injection cavity 11 .

[0029] The specific working process is as follows: the mixing screw 33 rotates, and the solid magnesium raw material enters the slurry preparation barrel 301 from the feed hopper 31. The solid material is sheared by the rotation of the mixing screw 33, and is stirred to form a semi-solid magnesium alloy slurry combined with the synchronous heating of the heating rods on the outside and the core of the screw. The semi-solid magnesium alloy slurry falls into the storage barrel 5, the metering pump works, the one-way valve 13 opens, and the semi-solid magnesium alloy slurry is transported to the injection cavity 11. During the transportation process, the one-way valve 30 is opened and the protective gas is introduced to ensure that the slurry can be smoothly input into the injection cavity 11; when the metering pump has measured in place, the metering pump stops running, and the pressure head 16 advances slowly. When the pressure head exceeds the feed port 12, the one-way valve 13 is closed, and then the pressure head 16 advances at high speed to inject the slurry into the forming mold 2 for forming. During the advancement of the pressure head 16, the mixing screw 33 does not stop working and stores material synchronously, causing the liquid level in the storage barrel 5 to rise. During this process, the one-way valve 36 opens to discharge the internal gas; when the liquid level in the storage barrel 5 is detected by the probe of the liquid level sensor 39, the mixing screw 33 stops rotating.

[0030] The comparative data on the performance of magnesium alloy products produced by traditional die casting and magnesium alloy products produced by this magnesium alloy semi-solid die casting equipment are shown in the following table: .

Claims

1. A magnesium alloy semi-solid die-casting molding device, comprising a slurry supply device, a die-casting device, and a molding die having a molding cavity. After the slurry is supplied to the pressing device by the slurry supply device, the slurry is pressed into the molding cavity by the die-casting device to form the desired magnesium alloy product. The slurry supply device includes a slurry preparation mechanism and a quantitative supply mechanism. The slurry preparation mechanism and the die-casting device are sealed and connected via the quantitative supply mechanism. The slurry preparation mechanism is used to prepare solid raw materials into semi-solid magnesium alloy slurry. The semi-solid magnesium alloy slurry prepared by the slurry preparation mechanism is quantitatively supplied to the die-casting device via the quantitative supply mechanism.

2. A magnesium alloy semi-solid die casting device as claimed in claim 1, characterized in that The slurry preparation mechanism includes a slurry preparation cylinder with a feed hopper, a closed slurry preparation chamber is provided in the slurry preparation cylinder, the feed hopper is connected to the slurry preparation chamber, at least one mixing screw is provided in the slurry preparation chamber, and a heating mechanism for heating the slurry preparation chamber is provided on the outside of the slurry preparation cylinder.

3. A magnesium alloy semi-solid die casting device as claimed in claim 2, characterized in that A heating rod is arranged at the center of the mixing screw.

4. A magnesium alloy semi-solid die casting device as claimed in claim 2, characterized in that The slurry preparation cylinder is provided with an exhaust port communicated with the slurry preparation chamber, and a one-way valve is provided in the exhaust port.

5. The semi-solid die-casting equipment for magnesium alloy according to claim 2, characterized in that The slurry preparation cylinder is provided with an air inlet connected to the slurry preparation chamber for introducing protective gas, and a one-way valve is provided in the air inlet.

6. The semi-solid die-casting equipment for magnesium alloys according to claim 2, characterized in that A liquid level sensor is provided at the tail of the slurry preparation tube, and a probe of the liquid level sensor is extended into the slurry preparation cavity.

7. The semi-solid die-casting equipment for magnesium alloy according to claim 2, characterized in that The quantitative supply mechanism is a quantitative pump, the feed hopper is connected to the upper part of the head end of the slurry preparation chamber, the lower part of the tail end of the slurry preparation chamber is provided with a discharge port, and the discharge port is sealed with at least one storage barrel. The die-casting device has an injection chamber, and the die-casting device is provided with a feed port connected to the injection chamber. A one-way valve is provided in the feed port, and the storage barrel and the feed port are sealed and connected through the quantitative pump.

8. The semi-solid die-casting equipment for magnesium alloys according to claim 7, characterized in that An induction coil is arranged outside the storage barrel.

9. The semi-solid die-casting equipment for magnesium alloy according to claim 7, characterized in that A heating device for heating the injection cavity is provided on the outside of the die-casting device.

10. The semi-solid die-casting equipment for magnesium alloy according to claim 7, characterized in that A pressure head is movably arranged in the injection cavity.

Images