CN115608953A - Mold Temperature Control Method of Dual-loop Die Casting for Al-Mg Alloy - Google Patents

Abstract

The invention discloses a method for controlling the temperature of an aluminum-magnesium alloy die-casting double-circuit mold. The steps include: step 1, setting a temperature control area; step 2, setting a temperature sensor, a pressure sensor, oil pipes and water pipes in the temperature control area; step 3, setting the Preheating the die-casting mold, step 4, injecting liquid magnesium-aluminum alloy into the die-casting mold; step 5, adjusting the pressure in the die-casting mold; step 6, adjusting the temperature and flow rate of the heat transfer oil and the flow rate of cooling water. In the present invention, by dividing several temperature control zones in the die-casting mold, not only can the die-casting mold be heated quickly and evenly to achieve dynamic thermal balance, but also the temperature difference of each temperature control zone can be adjusted, which can reduce the deformation of the alloy casting and ensure the alloy The quality of the casting, while adjusting the pressure in the die-casting mold, the temperature and flow of the heat transfer oil, and the flow of the cooling water, can control the temperature in the mold more flexibly, allowing the magnesium-aluminum alloy in the die-casting mold to be cooled, crystallized, and solidified. .

Description

Mold Temperature Control Method of Dual Circuits for Aluminum-magnesium Alloy Die-casting

technical field

The invention relates to the technical field of alloy die-casting, in particular to a method for controlling the temperature of an aluminum-magnesium alloy die-casting double-loop mold.

Background technique

Magnesium alloy and aluminum alloy die-casting is an advanced special precision casting process. It is to inject molten liquid magnesium alloy and aluminum alloy into the pressure chamber of the die-casting machine mechanically, and then through the high-speed movement of the injection punch, the liquid magnesium The alloy and aluminum alloy fill the mold cavity at high speed under high pressure, and the liquid magnesium alloy and aluminum alloy are rapidly cooled, crystallized and solidified under pressure. Compared with ordinary castings, precision die castings have the characteristics of complex structure, dense internal structure, excellent mechanical properties, high dimensional accuracy, and good surface quality.

When die-casting magnesium alloys and aluminum alloys, it is necessary to select a matching die-casting machine and die-casting process according to the characteristics of the mold product, mainly to adjust and control the pressure, speed, and stroke changes in the die-casting process, and to control the injection time and cooling time. , energy storage time and ejection time, through the control of liquid magnesium alloy, aluminum alloy and mold temperature, select a release agent with superior performance to die-cast qualified products. For this reason, a dual-circuit mold temperature control method for aluminum-magnesium alloy die-casting is proposed .

Contents of the invention

The main purpose of the present invention is to provide a method for controlling the temperature of aluminum-magnesium alloy die-casting dual-circuit molds, which can effectively solve the problems in the background technology.

In order to achieve the above object, the technical scheme that the present invention takes is:

The aluminum-magnesium alloy die-casting double-loop mold temperature control method is used to adjust the mold temperature of the die-casting machine, using heat transfer oil and cooling water as the temperature transfer medium, and the steps include:

Step 1. Setting several temperature control zones in the die-casting mold;

Step 2. Install temperature sensors, pressure sensors, oil pipes and water pipes in each temperature control area, connect the oil pipes to the mold temperature controller, and connect the water pipes to the water pump to form a circulating oil circuit and a circulating water circuit;

Step 3. Use the mold temperature controller to cooperate with the oil pipe to preheat the temperature control area. The specific process is as follows:

a. First pass protective gas into the die-casting mold;

b. Set the temperature in the die-casting mold at 600-720°C. The temperature in each temperature control zone is set according to the requirements of the casting. When the temperature in the die-casting mold reaches the set value, the temperature sensor feedbacks the mold temperature control machine Stop heating, when the temperature in the die-casting mold is lower than the set value, the temperature sensor feedback controls the mold temperature controller to continue heating;

Step 4: Inject liquid magnesium-aluminum alloy into the die-casting mold, and the injection specific pressure is 30-90MPa;

Step 5. After the liquid magnesium-aluminum alloy is injected into the die-casting mold, adjust the pressure in the die-casting mold so that the pressure in the die-casting mold is guaranteed to be 60-160 MPa;

Step 6. Adjust the temperature and flow rate of the heat transfer oil through the mold temperature controller, and adjust the flow rate of the cooling water through the water pump, so that the liquid magnesium aluminum alloy in the die-casting mold is cooled and formed, and the cooling rate in the die-casting mold is guaranteed to be 30-60°C/min .

Preferably, in the first step, the oil pipes in each temperature control zone run through the die-casting mold, the oil pipes in each temperature control zone are connected in parallel, and each temperature control zone corresponds to a mold temperature control machine.

Preferably, the temperature sensor in the second step is used to monitor the temperature in the die-casting mold in real time and send the temperature information to the mold temperature controller, and the pressure sensor in the second step is used to monitor the pressure in the die-casting mold.

Preferably, the protective gas in the third step is preferably nitrogen, and the purpose of introducing the protective gas in the third step is to prevent the liquid magnesium aluminum alloy from being oxidized in contact with the air in the die-casting mold.

Preferably, the purpose of preheating the inside of the die-casting mold in the third step is to achieve dynamic heat balance between the die-casting mold and the liquid magnesium-aluminum alloy during the die-casting process.

Preferably, in the step five, increasing the pressure in the die-casting mold is used to compact the magnesium-aluminum alloy casting, improve the density of the casting, and make the contour of the die-casting clear.

Preferably, the flow rate of the heat transfer oil and the cooling water in the step 6 is controlled at 1-4m ³ /min.

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

The present invention divides several temperature control areas in the die-casting mold, and cooperates with the mold temperature control machine to supply oil to control the temperature of each temperature control area, which not only allows the die-casting mold to be heated quickly and uniformly, realizes dynamic heat balance, but also adjusts The temperature difference in each temperature control zone can reduce the deformation of the alloy casting and ensure the quality of the alloy casting. At the same time, the pressure in the die-casting mold and the temperature and flow of the heat transfer oil and the flow of cooling water can be adjusted to control the temperature in the mold more flexibly. , can make the magnesium-aluminum alloy in the die-casting mold be uniformly cooled, crystallized, solidified and formed.

detailed description

In order to make the technical means, creative features, goals and effects achieved by the present invention easy to understand, the technical solutions in the present invention will be further clearly and completely described below in conjunction with specific embodiments. Obviously, the described embodiments are only Some, but not all, embodiments of the invention. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the protection scope of the present invention.

Aluminum-magnesium alloy die-casting double-circuit mold temperature control method is used to adjust the mold temperature of the die-casting machine, using heat transfer oil and cooling water as the temperature transfer medium, because the heat transfer oil has the advantages of high boiling point and fast heat conduction, it can control the die-casting mold more flexibly temperature, the steps include:

Step 1. Setting several temperature control zones in the die-casting mold;

Step 2. Install temperature sensors, pressure sensors, oil pipes and water pipes in each temperature control area, connect the oil pipes to the mold temperature controller, and connect the water pipes to the water pump to form a circulating oil circuit and a circulating water circuit;

Step 3. Use the mold temperature controller to cooperate with the oil pipe to preheat the die-casting mold. The specific process is as follows:

a. First pass protective gas into the die-casting mold;

b. Set the temperature in the die-casting mold at 600-720°C. The temperature in each temperature control zone is set according to the requirements of the casting. When the temperature in the die-casting mold reaches the set value, the temperature sensor feedbacks the mold temperature control machine Stop heating, when the temperature in the die-casting mold is lower than the set value, the temperature sensor feedback controls the mold temperature controller to continue heating;

Step 4: Inject liquid magnesium-aluminum alloy into the die-casting mold, and the injection specific pressure is 30-90MPa;

Step 5. After the liquid magnesium-aluminum alloy is injected into the die-casting mold, adjust the pressure in the die-casting mold so that the pressure in the die-casting mold is guaranteed to be 60-160 MPa;

Step 6. Adjust the temperature and flow rate of the heat transfer oil through the mold temperature controller, and adjust the flow rate of the cooling water through the water pump, so that the liquid magnesium aluminum alloy in the die-casting mold is cooled and formed, and the cooling rate in the die-casting mold is guaranteed to be 30-60°C/min .

In the first step, the oil pipes in each temperature control zone run through the die-casting mold to facilitate the connection of the oil pipes with the mold temperature controller. The oil pipes in each temperature control zone are connected in parallel, and branch pipes can be added in parallel. It is conducive to heating the inside of the die-casting mold. Each temperature control zone corresponds to a mold temperature control machine, which can realize independent control of each temperature control zone and facilitate the adjustment of the temperature difference of each temperature control zone.

The temperature sensor in the second step is used to monitor the temperature in the die-casting mold in real time and send the temperature information to the mold temperature control machine, and the pressure sensor in the second step is used to monitor the pressure in the die-casting mold.

The protective gas in the step 3 is preferably nitrogen. When the nitrogen gas is introduced into the die-casting mold, the air in the die-casting mold can be discharged. The purpose of introducing the protective gas in the step 3 is to prevent the liquid magnesium aluminum alloy from contacting the die-casting mold. Oxidation occurs in contact with air inside.

The purpose of preheating the inside of the die-casting mold in step 3 is to allow the die-casting mold and the liquid magnesium-aluminum alloy to achieve a dynamic thermal balance during the die-casting process, so that the liquid magnesium-aluminum alloy can continue to be heated when entering the die-casting mold and maintain a constant temperature, thereby It can reduce the deformation of alloy castings and reduce casting defects.

In the fifth step, increasing the pressure in the die-casting mold is used to compact the magnesium-aluminum alloy casting, improve the density of the casting, and make the contour of the die-casting clear.

In the sixth step, the temperature and flow rate of the heat transfer oil are adjusted by the mold temperature controller, and the flow rate of the cooling water is adjusted with the water pump, so that the liquid magnesium-aluminum alloy in the die-casting mold can conduct continuous heat exchange, which is beneficial to the cooling of the liquid magnesium-aluminum alloy For molding, the flow rate of heat transfer oil and cooling water is controlled at 1-4m ³ /min, which not only allows the heat transfer oil and cooling water to quickly take away the heat of liquid magnesium and aluminum alloys, but also allows the temperature in the die-casting mold to drop at a constant speed to prevent liquid magnesium The sudden drop in temperature of the aluminum alloy causes air bubbles to appear inside.

Example 1

Step 1, setting a temperature control zone in the die-casting mold;

Step 2. Set temperature sensor, pressure sensor, oil pipe and water pipe in the temperature control area, let the ends of the oil pipe and water pipe pass through the surface of the die-casting mold, connect the oil pipe to the mold temperature controller through the outer pipe, and connect the water pipe to the water pump , forming a circulating oil circuit and a circulating water circuit, the temperature in the die-casting mold can be monitored in real time through the temperature sensor in the temperature control area, and the temperature information is sent to the mold temperature controller, and the pressure sensor is used to monitor the pressure in the die-casting mold;

Step 3. Use the mold temperature controller to cooperate with the oil pipe to preheat the die-casting mold. The specific process is as follows:

a. First pass protective gas into the die-casting mold, and when nitrogen gas is introduced into the die-casting mold, the air in the die-casting mold can be discharged to prevent the liquid magnesium aluminum alloy from contacting with the air in the die-casting mold to oxidize;

b. Set the temperature in the die-casting mold at 640-680°C. When the temperature in the die-casting mold reaches the set value, the temperature sensor feedback controls the mold temperature controller to stop heating. When the temperature in the die-casting mold is lower than the set value When the temperature sensor feeds back to control the mold temperature controller to continue heating, when the temperature in the die-casting mold reaches the set temperature, the dynamic heat balance between the die-casting mold and the liquid magnesium-aluminum alloy can be realized, so that the liquid magnesium-aluminum alloy can enter the die-casting mold. Continue to be heated and maintain a constant temperature, so as to reduce the deformation of alloy castings and reduce casting defects;

Step 4: Inject liquid magnesium-aluminum alloy into the die-casting mold, and the injection specific pressure is 60-80MPa;

Step 5. After the liquid magnesium-aluminum alloy is injected into the die-casting mold, adjust the pressure in the die-casting mold to keep the pressure in the die-casting mold at 120-140MPa, which can increase the density of the casting and make the outline of the die-casting part clear;

Step 6. Adjust the temperature and flow rate of the heat transfer oil through the mold temperature controller, and adjust the flow rate of the cooling water with the water pump, so that the flow rate of the heat transfer oil and cooling water is 1~2m ³ /min, and the cooling rate in the die-casting mold is guaranteed to be 30~ 40°C/min, the liquid magnesium-aluminum alloy in the die-casting mold can conduct continuous heat exchange, and the heat transfer oil and cooling water can quickly take away the heat of the liquid magnesium-aluminum alloy, so that the liquid magnesium-aluminum alloy in the die-casting mold can be cooled and formed. To prevent the sudden drop in temperature of the liquid magnesium-aluminum alloy and cause internal air bubbles.

Example 2

Step 1, setting a temperature control zone in the die-casting mold;

Step 2. Set temperature sensor, pressure sensor, oil pipe and water pipe in the temperature control area, let the ends of the oil pipe and water pipe pass through the surface of the die-casting mold, connect the oil pipe to the mold temperature controller through the outer pipe, and connect the water pipe to the water pump , forming a circulating oil circuit and a circulating water circuit, the temperature in the die-casting mold can be monitored in real time through the temperature sensor in the temperature control area, and the temperature information is sent to the mold temperature controller, and the pressure sensor is used to monitor the pressure in the die-casting mold;

Step 3. Use the mold temperature controller to cooperate with the oil pipe to preheat the die-casting mold. The specific process is as follows:

a. First pass protective gas into the die-casting mold, and when nitrogen gas is introduced into the die-casting mold, the air in the die-casting mold can be discharged to prevent the liquid magnesium aluminum alloy from contacting with the air in the die-casting mold to oxidize;

b. Set the temperature in the die-casting mold at 640-680°C. When the temperature in the die-casting mold reaches the set value, the temperature sensor feedback controls the mold temperature controller to stop heating. When the temperature in the die-casting mold is lower than the set value When the temperature sensor feeds back to control the mold temperature controller to continue heating, when the temperature in the die-casting mold reaches the set temperature, the dynamic heat balance between the die-casting mold and the liquid magnesium-aluminum alloy can be realized, so that the liquid magnesium-aluminum alloy can enter the die-casting mold. Continue to be heated and maintain a constant temperature, so as to reduce the deformation of alloy castings and reduce casting defects;

Step 4: Inject liquid magnesium-aluminum alloy into the die-casting mold, and the injection specific pressure is 60-80MPa;

Step 5. After the liquid magnesium-aluminum alloy is injected into the die-casting mold, adjust the pressure in the die-casting mold to keep the pressure in the die-casting mold at 120-140MPa, which can increase the density of the casting and make the outline of the die-casting part clear;

Step 6. Adjust the temperature and flow rate of the heat transfer oil through the mold temperature controller, and adjust the flow rate of the cooling water with the water pump, so that the flow rate of the heat transfer oil and cooling water is controlled at 2 ~ 3m ³ /min, and the cooling rate in the die-casting mold is guaranteed at 40 ~50°C/min, allowing the liquid magnesium-aluminum alloy in the die-casting mold to conduct continuous heat exchange, allowing the heat transfer oil and cooling water to quickly take away the heat of the liquid magnesium-aluminum alloy, so that the liquid magnesium-aluminum alloy in the die-casting mold is cooled and formed , to prevent the sudden drop in temperature of the liquid magnesium-aluminum alloy and cause bubbles to appear inside.

Example 3

Step 1, setting a temperature control zone in the die-casting mold;

Step 2. Set temperature sensor, pressure sensor, oil pipe and water pipe in the temperature control area, let the ends of the oil pipe and water pipe pass through the surface of the die-casting mold, connect the oil pipe to the mold temperature controller through the outer pipe, and connect the water pipe to the water pump , forming a circulating oil circuit and a circulating water circuit, the temperature in the die-casting mold can be monitored in real time through the temperature sensor in the temperature control area, and the temperature information is sent to the mold temperature controller, and the pressure sensor is used to monitor the pressure in the die-casting mold;

Step 3. Use the mold temperature controller to cooperate with the oil pipe to preheat the die-casting mold. The specific process is as follows:

a. First pass protective gas into the die-casting mold, and when nitrogen gas is introduced into the die-casting mold, the air in the die-casting mold can be discharged to prevent the liquid magnesium aluminum alloy from contacting with the air in the die-casting mold to oxidize;

b. Set the temperature in the die-casting mold at 640-680°C. When the temperature in the die-casting mold reaches the set value, the temperature sensor feedback controls the mold temperature controller to stop heating. When the temperature in the die-casting mold is lower than the set value When the temperature sensor feeds back to control the mold temperature controller to continue heating, when the temperature in the die-casting mold reaches the set temperature, the dynamic heat balance between the die-casting mold and the liquid magnesium-aluminum alloy can be realized, so that the liquid magnesium-aluminum alloy can enter the die-casting mold. Continue to be heated and maintain a constant temperature, so as to reduce the deformation of alloy castings and reduce casting defects;

Step 4: Inject liquid magnesium-aluminum alloy into the die-casting mold, and the injection specific pressure is 60-80MPa;

Step 5. After the liquid magnesium-aluminum alloy is injected into the die-casting mold, adjust the pressure in the die-casting mold to keep the pressure in the die-casting mold at 120-140MPa, which can increase the density of the casting and make the outline of the die-casting part clear;

Step 6. Adjust the temperature and flow rate of the heat transfer oil through the mold temperature controller, and adjust the flow rate of the cooling water with the water pump, so that the flow rate of the heat transfer oil and cooling water is controlled at 3 ~ 4m ³ /min, and the cooling rate in the die-casting mold is guaranteed to be 50 ~60°C/min, allowing the liquid magnesium-aluminum alloy in the die-casting mold to conduct continuous heat exchange, allowing the heat transfer oil and cooling water to quickly take away the heat of the liquid magnesium-aluminum alloy, so that the liquid magnesium-aluminum alloy in the die-casting mold is cooled and formed , to prevent the sudden drop in temperature of the liquid magnesium-aluminum alloy and cause bubbles to appear inside.

Example 4

Step 1. Set up two temperature control zones in the die-casting mold;

Step 2. Set temperature sensor, pressure sensor, oil pipe and water pipe in the temperature control area, let the ends of the oil pipe and water pipe pass through the surface of the die-casting mold, connect the oil pipe to the mold temperature controller through the outer pipe, and connect the water pipe to the water pump , forming a circulating oil circuit and a circulating water circuit, the temperature in the die-casting mold can be monitored in real time through the temperature sensor in the temperature control area, and the temperature information is sent to the mold temperature controller, and the pressure sensor is used to monitor the pressure in the die-casting mold;

Step 3. Use the mold temperature controller to cooperate with the oil pipe to preheat the die-casting mold. The specific process is as follows:

a. First pass protective gas into the die-casting mold, and when nitrogen gas is introduced into the die-casting mold, the air in the die-casting mold can be discharged to prevent the liquid magnesium aluminum alloy from contacting with the air in the die-casting mold to oxidize;

b. Set the temperature of the first temperature control zone in the die-casting mold at 600-640°C, and the temperature of the second temperature-control zone at 640-680°C. When the temperature in the die-casting mold reaches the set value, The temperature sensor feedback controls the mold temperature control machine to stop heating. When the temperature in the die-casting mold is lower than the set value, the temperature sensor feedback controls the mold temperature control machine to continue heating. When the temperature in the die-casting mold reaches the set temperature, the die-casting can be realized. The dynamic heat balance between the mold and the liquid magnesium-aluminum alloy can allow the liquid magnesium-aluminum alloy to continue to be heated and maintain a constant temperature when it enters the die-casting mold, thereby reducing the deformation of the alloy casting and reducing casting defects;

Step 4: Inject liquid magnesium-aluminum alloy into the die-casting mold, and the injection specific pressure is 60-80MPa;

Step 5. After the liquid magnesium-aluminum alloy is injected into the die-casting mold, adjust the pressure in the die-casting mold to keep the pressure in the die-casting mold at 120-140MPa, which can increase the density of the casting and make the outline of the die-casting part clear;

Step 6. Adjust the temperature and flow rate of the heat transfer oil through the mold temperature controller, and adjust the flow rate of the cooling water with the water pump, so that the flow rate of the heat transfer oil and cooling water is controlled at 1-2m ³ /min, and the cooling rate in the die-casting mold is guaranteed to be 30 ~40°C/min, allowing the liquid magnesium-aluminum alloy in the die-casting mold to conduct continuous heat exchange, allowing the heat transfer oil and cooling water to quickly take away the heat of the liquid magnesium-aluminum alloy, so that the liquid magnesium-aluminum alloy in the die-casting mold is cooled and formed , to prevent the sudden drop in temperature of the liquid magnesium-aluminum alloy and cause bubbles to appear inside.

Example 5

Step 1. Set up two temperature control zones in the die-casting mold;

Step 2. Set temperature sensor, pressure sensor, oil pipe and water pipe in the temperature control area, let the ends of the oil pipe and water pipe pass through the surface of the die-casting mold, connect the oil pipe to the mold temperature controller through the outer pipe, and connect the water pipe to the water pump , forming a circulating oil circuit and a circulating water circuit, the temperature in the die-casting mold can be monitored in real time through the temperature sensor in the temperature control area, and the temperature information is sent to the mold temperature controller, and the pressure sensor is used to monitor the pressure in the die-casting mold;

Step 3. Use the mold temperature controller to cooperate with the oil pipe to preheat the die-casting mold. The specific process is as follows:

a. First pass protective gas into the die-casting mold, and when nitrogen gas is introduced into the die-casting mold, the air in the die-casting mold can be discharged to prevent the liquid magnesium aluminum alloy from contacting with the air in the die-casting mold to oxidize;

b. Set the temperature of the first temperature control zone in the die-casting mold at 600-640°C, and the temperature of the second temperature-control zone at 640-680°C. When the temperature in the die-casting mold reaches the set value, The temperature sensor feedback controls the mold temperature control machine to stop heating. When the temperature in the die-casting mold is lower than the set value, the temperature sensor feedback controls the mold temperature control machine to continue heating. When the temperature in the die-casting mold reaches the set temperature, the die-casting can be realized. The dynamic heat balance between the mold and the liquid magnesium-aluminum alloy can allow the liquid magnesium-aluminum alloy to continue to be heated and maintain a constant temperature when it enters the die-casting mold, thereby reducing the deformation of the alloy casting and reducing casting defects;

Step 4: Inject liquid magnesium-aluminum alloy into the die-casting mold, and the injection specific pressure is 60-80MPa;

Step 5. After the liquid magnesium-aluminum alloy is injected into the die-casting mold, adjust the pressure in the die-casting mold to keep the pressure in the die-casting mold at 120-140MPa, which can increase the density of the casting and make the outline of the die-casting part clear;

Step 6. Adjust the temperature and flow rate of the heat transfer oil through the mold temperature controller, and adjust the flow rate of the cooling water with the water pump, so that the flow rate of the heat transfer oil and cooling water is controlled at 2 ~ 3m ³ /min, and the cooling rate in the die-casting mold is guaranteed at 40 ~50°C/min, allowing the liquid magnesium-aluminum alloy in the die-casting mold to conduct continuous heat exchange, allowing the heat transfer oil and cooling water to quickly take away the heat of the liquid magnesium-aluminum alloy, so that the liquid magnesium-aluminum alloy in the die-casting mold is cooled and formed , to prevent the sudden drop in temperature of the liquid magnesium-aluminum alloy and cause bubbles to appear inside.

Example 6

Step 1. Set up two temperature control zones in the die-casting mold;

Step 2. Set temperature sensor, pressure sensor, oil pipe and water pipe in the temperature control area, let the ends of the oil pipe and water pipe pass through the surface of the die-casting mold, connect the oil pipe to the mold temperature controller through the outer pipe, and connect the water pipe to the water pump , forming a circulating oil circuit and a circulating water circuit, the temperature in the die-casting mold can be monitored in real time through the temperature sensor in the temperature control area, and the temperature information is sent to the mold temperature controller, and the pressure sensor is used to monitor the pressure in the die-casting mold;

Step 3. Use the mold temperature controller to cooperate with the oil pipe to preheat the die-casting mold. The specific process is as follows:

a. First pass protective gas into the die-casting mold, and when nitrogen gas is introduced into the die-casting mold, the air in the die-casting mold can be discharged to prevent the liquid magnesium aluminum alloy from contacting with the air in the die-casting mold to oxidize;

b. Set the temperature of the first temperature control zone in the die-casting mold at 600-640°C, and the temperature of the second temperature-control zone at 640-680°C. When the temperature in the die-casting mold reaches the set value, The temperature sensor feedback controls the mold temperature control machine to stop heating. When the temperature in the die-casting mold is lower than the set value, the temperature sensor feedback controls the mold temperature control machine to continue heating. When the temperature in the die-casting mold reaches the set temperature, the die-casting can be realized. The dynamic heat balance between the mold and the liquid magnesium-aluminum alloy can allow the liquid magnesium-aluminum alloy to continue to be heated and maintain a constant temperature when it enters the die-casting mold, thereby reducing the deformation of the alloy casting and reducing casting defects;

Step 4: Inject liquid magnesium-aluminum alloy into the die-casting mold, and the injection specific pressure is 60-80MPa;

Step 5. After the liquid magnesium-aluminum alloy is injected into the die-casting mold, adjust the pressure in the die-casting mold to keep the pressure in the die-casting mold at 120-140MPa, which can increase the density of the casting and make the outline of the die-casting part clear;

Step 6. Adjust the temperature and flow rate of the heat transfer oil through the mold temperature controller, and adjust the flow rate of the cooling water with the water pump, so that the flow rate of the heat transfer oil and cooling water is controlled at 3 ~ 4m ³ /min, and the cooling rate in the die-casting mold is guaranteed to be 50 ~60°C/min, allowing the liquid magnesium-aluminum alloy in the die-casting mold to conduct continuous heat exchange, allowing the heat transfer oil and cooling water to quickly take away the heat of the liquid magnesium-aluminum alloy, so that the liquid magnesium-aluminum alloy in the die-casting mold is cooled and formed , to prevent the sudden drop in temperature of the liquid magnesium-aluminum alloy and cause bubbles to appear inside.

Example 7

Step 1. Set three temperature control zones in the die-casting mold;

Step 2. Set temperature sensor, pressure sensor, oil pipe and water pipe in the temperature control area, let the ends of the oil pipe and water pipe pass through the surface of the die-casting mold, connect the oil pipe to the mold temperature controller through the outer pipe, and connect the water pipe to the water pump , forming a circulating oil circuit and a circulating water circuit, the temperature in the die-casting mold can be monitored in real time through the temperature sensor in the temperature control area, and the temperature information is sent to the mold temperature controller, and the pressure sensor is used to monitor the pressure in the die-casting mold;

Step 3. Use the mold temperature controller to cooperate with the oil pipe to preheat the die-casting mold. The specific process is as follows:

a. First pass protective gas into the die-casting mold, and when nitrogen gas is introduced into the die-casting mold, the air in the die-casting mold can be discharged to prevent the liquid magnesium aluminum alloy from contacting with the air in the die-casting mold to oxidize;

b. Set the temperature of the first temperature control zone in the die-casting mold at 600-640°C, the temperature of the second temperature control zone at 640-680°C, and the temperature of the third temperature control zone at 680°C ~720°C, when the temperature in the die-casting mold reaches the set value, the temperature sensor feedback controls the mold temperature controller to stop heating, when the temperature in the die-casting mold is lower than the set value, the temperature sensor feedback controls the mold temperature controller to continue heating , when the temperature in the die-casting mold reaches the set temperature, the dynamic heat balance between the die-casting mold and the liquid magnesium-aluminum alloy can be realized, and the liquid magnesium-aluminum alloy can continue to be heated when it enters the die-casting mold to keep a constant temperature, thereby reducing the alloy casting. Deformation, reduce casting defects;

Step 4. Inject liquid magnesium-aluminum alloy into the die-casting mold, and the injection specific pressure is 60-80MPa;

Step 5. After the liquid magnesium-aluminum alloy is injected into the die-casting mold, adjust the pressure in the die-casting mold to keep the pressure in the die-casting mold at 120-140MPa, which can increase the density of the casting and make the outline of the die-casting part clear;

Step 6. Adjust the temperature and flow rate of the heat transfer oil through the mold temperature controller, and adjust the flow rate of the cooling water with the water pump, so that the flow rate of the heat transfer oil and cooling water is controlled at 1-2m ³ /min, ensuring that the cooling rate in the die-casting mold is within 30～40℃/min, it can make the liquid magnesium aluminum alloy in the die-casting mold carry out continuous heat exchange, and the heat transfer oil and cooling water can quickly take away the heat of the liquid magnesium aluminum alloy, so that the liquid magnesium aluminum alloy in the die-casting mold can be cooled Forming to prevent the sudden drop in temperature of liquid magnesium aluminum alloy and cause internal bubbles.

Example 8

Step 1. Set three temperature control zones in the die-casting mold;

Step 2. Set temperature sensor, pressure sensor, oil pipe and water pipe in the temperature control area, let the ends of the oil pipe and water pipe pass through the surface of the die-casting mold, connect the oil pipe to the mold temperature controller through the outer pipe, and connect the water pipe to the water pump , forming a circulating oil circuit and a circulating water circuit, the temperature in the die-casting mold can be monitored in real time through the temperature sensor in the temperature control area, and the temperature information is sent to the mold temperature controller, and the pressure sensor is used to monitor the pressure in the die-casting mold;

Step 3. Use the mold temperature controller to cooperate with the oil pipe to preheat the die-casting mold. The specific process is as follows:

a. First pass protective gas into the die-casting mold, and when nitrogen gas is introduced into the die-casting mold, the air in the die-casting mold can be discharged to prevent the liquid magnesium aluminum alloy from contacting with the air in the die-casting mold to oxidize;

b. Set the temperature of the first temperature control zone in the die-casting mold at 600-640°C, the temperature of the second temperature control zone at 640-680°C, and the temperature of the third temperature control zone at 680°C ~720°C, when the temperature in the die-casting mold reaches the set value, the temperature sensor feedback controls the mold temperature controller to stop heating, when the temperature in the die-casting mold is lower than the set value, the temperature sensor feedback controls the mold temperature controller to continue heating , when the temperature in the die-casting mold reaches the set temperature, the dynamic heat balance between the die-casting mold and the liquid magnesium-aluminum alloy can be realized, and the liquid magnesium-aluminum alloy can continue to be heated when it enters the die-casting mold to keep a constant temperature, thereby reducing the alloy casting. Deformation, reduce casting defects;

Step 4: Inject liquid magnesium-aluminum alloy into the die-casting mold, and the injection specific pressure is 60-80MPa;

Step 5. After the liquid magnesium-aluminum alloy is injected into the die-casting mold, adjust the pressure in the die-casting mold to keep the pressure in the die-casting mold at 120-140MPa, which can increase the density of the casting and make the outline of the die-casting part clear;

Step 6. Adjust the temperature and flow rate of the heat transfer oil through the mold temperature controller, and adjust the flow rate of the cooling water with the water pump, so that the flow rate of the heat transfer oil and cooling water is controlled at 2 ~ 3m ³ /min to ensure that the cooling rate in the die-casting mold is at 40～50℃/min, it can make the liquid magnesium aluminum alloy in the die-casting mold carry out continuous heat exchange, and the heat transfer oil and cooling water can quickly take away the heat of the liquid magnesium aluminum alloy, so that the liquid magnesium aluminum alloy in the die-casting mold can be cooled Forming to prevent the sudden drop in temperature of liquid magnesium aluminum alloy and cause internal bubbles.

To sum up, through the comparison of Example 1, Example 2, and Example 3, by setting multiple temperature control zones, not only can the heating speed of the die-casting mold be accelerated, but also the heating effect can be made more uniform. The temperature difference in the temperature control area can reduce the deformation of alloy castings, ensure the quality of alloy castings, and can also speed up the cooling speed of liquid magnesium alloys and aluminum alloys, which is conducive to rapid cooling, crystallization, and rapid crystallization of liquid magnesium alloys and aluminum alloys. , Solidification molding.

Example 9

Step 1. Set three temperature control zones in the die-casting mold;

Step 2. Set temperature sensor, pressure sensor, oil pipe and water pipe in the temperature control area, let the ends of the oil pipe and water pipe pass through the surface of the die-casting mold, connect the oil pipe to the mold temperature controller through the outer pipe, and connect the water pipe to the water pump , forming a circulating oil circuit and a circulating water circuit, the temperature in the die-casting mold can be monitored in real time through the temperature sensor in the temperature control area, and the temperature information is sent to the mold temperature controller, and the pressure sensor is used to monitor the pressure in the die-casting mold;

Step 3. Use the mold temperature controller to cooperate with the oil pipe to preheat the die-casting mold. The specific process is as follows:

a. First pass protective gas into the die-casting mold, and when nitrogen gas is introduced into the die-casting mold, the air in the die-casting mold can be discharged to prevent the liquid magnesium aluminum alloy from contacting with the air in the die-casting mold to oxidize;

b. Set the temperature of the first temperature control zone in the die-casting mold at 600-640°C, the temperature of the second temperature control zone at 640-680°C, and the temperature of the third temperature control zone at 680°C ~720°C, when the temperature in the die-casting mold reaches the set value, the temperature sensor feedback controls the mold temperature controller to stop heating, when the temperature in the die-casting mold is lower than the set value, the temperature sensor feedback controls the mold temperature controller to continue heating , when the temperature in the die-casting mold reaches the set temperature, the dynamic heat balance between the die-casting mold and the liquid magnesium-aluminum alloy can be realized, and the liquid magnesium-aluminum alloy can continue to be heated when it enters the die-casting mold to keep a constant temperature, thereby reducing the alloy casting. Deformation, reduce casting defects;

Step 4: Inject liquid magnesium-aluminum alloy into the die-casting mold, and the injection specific pressure is 60-80MPa;

Step 5. After the liquid magnesium-aluminum alloy is injected into the die-casting mold, adjust the pressure in the die-casting mold to keep the pressure in the die-casting mold at 120-140MPa, which can increase the density of the casting and make the outline of the die-casting part clear;

Step 6. Adjust the temperature and flow rate of the heat transfer oil through the mold temperature controller, and adjust the flow rate of the cooling water with the water pump, so that the flow rate of the heat transfer oil and cooling water is controlled at 3 ~ 4m ³ /min to ensure that the cooling rate in the die-casting mold is at 50～60℃/min, it can make the liquid magnesium aluminum alloy in the die-casting mold carry out continuous heat exchange, and the heat transfer oil and cooling water can quickly take away the heat of the liquid magnesium aluminum alloy, so that the liquid magnesium aluminum alloy in the die-casting mold can be cooled Forming to prevent the sudden drop in temperature of liquid magnesium aluminum alloy and cause internal bubbles.

The collar property test table of the magnesium-aluminum alloy casting that table 1 embodiment 1-9 prepares

project Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 Example 7 Example 8 Example 9 Cooling time, min 50 45 35 48 45 33 51 44 34 Deformation rate, % 1 1.2 1 1 1 1.1 0.8 1 1 Whether there are bubbles inside the casting no no no no no no no no no

It can be seen from the above data that by controlling the temperature of the die-casting mold in the present invention, the deformation of the alloy casting can be effectively reduced, the defects of the casting can be reduced, and the quality of the alloy casting can be guaranteed.

It should be noted that the same embodiment and different embodiments of the present invention can be combined with each other. The above is only a preferred embodiment of the present invention. Those skilled in the industry should understand that the scope of protection of the present invention is not limited to the above embodiments. , what is described in the above-mentioned embodiments and description is only to illustrate the principle of the present invention, and without departing from the spirit and scope of the present invention, there will be various changes and improvements in the present invention, and these changes and improvements all fall into the scope of the claimed invention. within the scope of the invention. The protection scope of the present invention is defined by the appended claims and their equivalents.

Claims (7)

1. The aluminum-magnesium alloy die-casting double-loop die temperature control method is characterized by comprising the following steps of: the method is used for adjusting the temperature of a die casting machine, uses heat conduction oil and cooling water as temperature conduction media, and comprises the following steps:

step one, arranging a plurality of temperature control areas in a die-casting die;

step two, arranging a temperature sensor, a pressure sensor, an oil pipe and a water pipe in each temperature control area, connecting the oil pipe with a mold temperature control machine, and connecting the water pipe with a water pump to form a circulating oil path and a circulating water path;

step three, preheating the interior of the die-casting die by utilizing a die temperature controller and matching with an oil pipe, wherein the specific process is as follows:

a. firstly, introducing protective gas into a die-casting die;

b. setting the temperature in the die-casting die at 600-720 ℃, specifically setting the temperature in each temperature control area according to the requirement of a casting, when the temperature in the die-casting die reaches a set value, feeding back a temperature sensor to control a die temperature controller to stop heating, and when the temperature in the die-casting die is lower than the set value, feeding back the temperature sensor to control the die temperature controller to continue heating;

injecting liquid magnesium-aluminum alloy into the die-casting die, wherein the injection specific pressure is 30-90 MPa;

step five, after the liquid magnesium-aluminum alloy is injected into the die-casting die, adjusting the pressure in the die-casting die to ensure that the pressure value in the die-casting die is between 60 and 160MPa;

and step six, adjusting the temperature and the flow of the heat conduction oil through a mold temperature controller, and adjusting the flow of cooling water through a water pump, so that the liquid magnesium-aluminum alloy in the die-casting mold is cooled and formed, and the cooling speed in the die-casting mold is ensured to be 30-60 ℃/min.

2. The aluminum magnesium alloy die-casting double-loop die temperature control method according to claim 1, characterized in that: in the first step, the oil pipe in each temperature control area penetrates through the die-casting die, the oil pipes in each temperature control area are connected in parallel, and each temperature control area corresponds to one die temperature controller.

3. The aluminum magnesium alloy die-casting double-loop die temperature control method according to claim 1, characterized in that: and the temperature sensor in the second step is used for monitoring the temperature in the die-casting die in real time and sending temperature information to the die temperature controller, and the pressure sensor in the second step is used for monitoring the pressure in the die-casting die.

4. The aluminum magnesium alloy die-casting double-loop die temperature control method according to claim 1, characterized in that: the protective gas in the third step is preferably nitrogen, and the purpose of introducing the protective gas in the third step is to prevent the liquid magnesium-aluminum alloy from being oxidized when contacting with the air in the die-casting die.

5. The aluminum magnesium alloy die-casting double-loop die temperature control method according to claim 1, characterized in that: and in the third step, the interior of the die-casting die is preheated so as to realize dynamic heat balance between the die-casting die and the liquid magnesium aluminum alloy in the die-casting process.

6. The aluminum magnesium alloy die-casting double-loop die temperature control method according to claim 1, characterized in that: and in the fifth step, the pressure in the die-casting die is increased to compact the magnesium-aluminum alloy casting, so that the density of the casting is improved, and the outline of the die-casting is clear.

7. The aluminum magnesium alloy die-casting double-loop die temperature control method according to claim 1, characterized in that: in the sixth step, the flow of the heat conduction oil and the cooling water is controlled to be 1-4 m ³ /min。