A method for preparing a large-size magnesium alloy ingot

Abstract

The application provides a large-size magnesium alloy ingot preparation method, and the steps include: alloy melt pouring, starting a cooling system, monitoring the temperature of different parts of the ingot mold, opening a water inlet valve, making the water level in the cooling chamber rise at a speed of 80-100 mm / min, closing all nozzles of each layer whenever the water level reaches the height of the nozzles of the layer, opening a water outlet valve when the water level reaches the top of the cooling chamber, and quickly adjusting the water flow to make the water inlet amount equal to the water outlet amount; when the temperature of the ingot is lower than 200 DEG C, closing the water inlet valve, taking out the ingot after the water in the cooling chamber is drained, washing the ingot with water for 3-5 min, and then air cooling to room temperature. The application not only greatly improves the material utilization rate in the preparation process of the large-size magnesium alloy ingot, but also significantly reduces the production cost of the large-size magnesium alloy ingot, and can effectively avoid the casting defects such as air entrapment and pinhole of the melt in the pouring process of the large-size ingot.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of magnesium alloy casting, and particularly relates to a large-specification magnesium alloy ingot preparation method. BACKGROUND

[0002] A big bottleneck of high-performance magnesium alloy component forming is the preparation of large-specification magnesium alloy ingot blank, and the difficulties include: first, the internal quality of the large-specification ingot is difficult to control, and shrinkage, pores and composition segregation are serious; second, the shrinkage stress of the large-specification magnesium alloy ingot is large during the cooling process, and the ingot is prone to cracking. Especially for the magnesium alloy ingot with a diameter greater than 700 mm and a length greater than 750 mm, the semi-continuous casting method not only requires complex equipment, but also has a large temperature difference between the inside and outside of the ingot, which leads to serious composition segregation or cracking, resulting in low qualified rate of the ingot blank and high preparation cost. More importantly, it is impossible to mass-produce large-specification magnesium alloy ingots.

[0003] At present, in the preparation process of large-specification magnesium alloy ingots, artificial intervention is mainly performed on the temperature field of the ingot solidification process, so that the ingot realizes rapid sequential solidification from the bottom end to the top end. In the prior art, in the scheme of document CN 102626779A, after the alloy is melted, the whole crucible is moved into the solidification system, and a bottom water spraying cooling method is used to realize the function of directional solidification, so as to obtain a magnesium alloy ingot with good surface and internal quality; in the scheme of document CN 106834766B, after the magnesium liquid is poured into the mold, a water cooling method is used to realize rapid directional cooling from the bottom, which effectively eliminates the composition segregation of the ingot and avoids the cracking of the ingot. However, in the preparation process of large-specification magnesium alloy ingots, the foregoing schemes have the problem of low material utilization rate. Taking a magnesium alloy ingot with a diameter of 680 mm and a length of 800 mm as an example, the top of the obtained casting still has a non-qualified segment of about 150 mm which cannot be utilized.

[0004] In addition, for large-specification magnesium alloy ingots, the existing method usually directly extends the melt delivery pipeline into the cavity, and there is a problem of gas entrainment during the pouring of the magnesium alloy melt. How to effectively avoid gas entrainment during the pouring of the magnesium alloy melt is also a problem to be solved. SUMMARY

[0005] At least to solve the technical problems mentioned in the background, the application aims to provide a large-specification magnesium alloy ingot preparation method.

[0006] The application adopts the following technical scheme.

[0007] A large-specification magnesium alloy ingot preparation method, the steps of which include:

[0008] Step 1, after the alloy melt reaches the pouring temperature, first introduce the protective atmosphere to the bottom of the ingot mold, then deliver the alloy melt into the ingot mold through the pipeline, cover the top of the mold with the heat preservation cotton after the pouring is completed;

[0009] The ingot mold comprises a cavity, the ingot mold is provided with temperature monitoring points, and a circumferential cooling system is arranged on the periphery of the cavity; the circumferential cooling system comprises a cooling chamber, a plurality of layers of nozzles are arranged in the cooling chamber from top to bottom at intervals, the height covered by all the nozzles is not less than the height of the melt filled in the cavity, each layer of nozzles arranged horizontally is connected with a water inlet pipe, the water inlet pipe is connected with a fluid medium supply system, a water inlet valve is arranged on the water inlet pipe, and a water outlet valve is arranged on the liquid discharge pipe section of the circumferential cooling system;

[0010] Step 2, start the cooling system, monitor the temperature of different parts of the ingot mold at the same time, and sequentially implement the following cooling operations:

[0011] Step 21, first open the first layer of nozzles, use the spray of the first layer of nozzles to cool the ingot mold for 3-5 min, then open the second layer of nozzles, use the spray of the second layer of nozzles to cool the ingot mold for 3-5 min, and so on until the top layer of nozzles is opened to spray and cool the ingot mold;

[0012] Step 22, adjust the flow of the first layer of nozzles, use the spray liquid of the first layer of nozzles to cool the ingot mold for 2-3 min, then adjust the flow of the second layer of nozzles, use the spray liquid of the second layer of nozzles to cool the ingot mold for 2-3 min, and so on until the top layer of nozzles is opened to spray and cool the ingot mold;

[0013] Step 3, open the water inlet valve, and make the water level in the cooling chamber rise at a speed of 80-100 mm / min, whenever the water level reaches the height of each layer of nozzles, close all the nozzles of the layer, until the water level reaches the top of the cooling chamber, open the water outlet valve, and quickly adjust the water flow to make the water inlet amount equal to the water outlet amount;

[0014] Step 4, when the temperature of the ingot is lower than 200℃, close the water inlet valve, after the water in the cooling chamber is discharged, take out the ingot, wash it with water for 3-5 min, and then air cool to room temperature.

[0015] As a preferred solution, 4 nozzles are distributed in each layer for Ф400~Ф600mm ingot, 6 nozzles are distributed in each layer for Ф600~Ф800mm ingot, 8 nozzles are distributed in each layer for Ф800~Ф1000mm ingot, 10 nozzles are distributed in each layer for Ф1000~Ф1200mm ingot, 12 nozzles are distributed in each layer for Ф1200~Ф1400mm ingot, 14 nozzles are distributed in each layer for Ф1400~Ф1600mm ingot, 16 nozzles are distributed in each layer for Ф1600~Ф1800mm ingot, and 18 nozzles are distributed in each layer for Ф1800~Ф2000mm ingot.

[0016] As a preferred solution, the protective atmosphere used in step 1 is 70% Ar + 30% CO2.

[0017] In order to effectively avoid the gas rolling in the magnesium alloy melt pouring process, the lower section of the pipe in the mold cavity is in a serpentine structure and vertically arranged, and the length of the lower section of the pipe (i.e. the serpentine structure) is equal to half of the height of the mold cavity. With such a solution, it can be ensured that the melt in the pipe always flows uniformly and smoothly in a cylindrical structure into the mold cavity, while when the lower section of the pipe is a straight section, the melt in the pipe will flow into the mold cavity in a twisted structure, thereby causing the gas rolling (part of the gas is rolled into the melt).

[0018] In order to more effectively avoid the gas rolling in the magnesium alloy melt pouring process, the lower section of the pipe is close to the bottom of the side wall of the mold cavity, and the outlet of the lower section of the pipe is horizontally oriented towards the side wall of the mold cavity. Further, the radius of the arc-shaped part of the lower section of the pipe is 40~70mm. As a preferred solution, the water inlet pipe is located between the first layer of nozzles and the drain pipe / drain valve.

[0019] Beneficial effects: With the solution of the present application, not only the material utilization rate in the preparation process of large-size magnesium alloy ingot is greatly improved, but also the production cost of large-size magnesium alloy ingot is significantly reduced, and the casting defects such as gas rolling and pinhole of the melt in the large-size ingot during pouring process can be effectively avoided; the present application effectively solves the serious quality problems such as porosity and shrinkage cavity of large-size ingot, and prevents the problems such as through-hole cracking of the ingot caused by excessive cooling intensity, and the obtained large-size ingot has a compact structure. More importantly, the present application can realize the continuous batch production of large-size magnesium alloy ingot with extremely simple equipment, and the corresponding equipment can be repeatedly used and has good versatility. BRIEF DESCRIPTION OF DRAWINGS

[0020] Figure 1 The figure is a schematic diagram of the equipment used in the preparation of large-size magnesium alloy ingot in the embodiment. DETAILED DESCRIPTION

[0021] The technical solutions in the present application will be described clearly and completely below with reference to the drawings. Obviously, the described embodiments are only some of the embodiments of the present application, but not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work fall within the scope of the present application.

[0022] Embodiment 1

[0023] In combination Figure 1 As shown in the figure, a large-size magnesium alloy ingot preparation method is used to prepare an AZ80 magnesium alloy ingot with a diameter of 800 mm and a height of 1200 mm. The steps include:

[0024] Step 1: After the alloy melt reaches the pouring temperature of 700℃, first introduce a protective atmosphere into the bottom of the preheated ingot mold to 320℃, and the protective atmosphere used is 70% Ar + 30% CO2. Then, through the pipeline 5, the alloy melt is transported into the ingot mold, and after pouring is completed, the top of the mold is covered with heat preservation cotton.

[0025] The ingot mold includes a cavity 1, and the ingot mold is provided with a temperature monitoring point, and a circumferential cooling system is arranged outside the cavity 1. The circumferential cooling system includes a cooling chamber 2, and six layers of nozzles 22 are arranged in the cooling chamber 2 from top to bottom. The height difference between adjacent layers of nozzles 22 is 150 mm, and six nozzles 22 are uniformly arranged in each layer. Nozzles are not arranged within 300 mm in height from the top end of the ingot mold. The height covered by all nozzles 22 is not less than the height of the melt filled in the cavity 1. Each layer of horizontally arranged nozzles 22 is connected to a water inlet pipe 21, and the water inlet pipe 21 is connected to a fluid medium supply system. The water inlet pipe 21 is provided with a water inlet valve 25, and the drainage valve 26 is arranged on the drainage pipe section of the circumferential cooling system. The water inlet pipe 21 is located between the first layer of nozzles 221 and the drainage pipe.

[0026] The lower section 4 of the pipeline is in a serpentine structure and arranged vertically. The length of the lower section 4 (i.e. the serpentine structure) is equal to half the height of the cavity. The lower section 4 is close to the bottom of the side wall of the cavity 1. The outlet of the lower section 4 horizontally faces the side wall of the cavity 1. The radius of the arc-shaped part of the lower section 4 is 45 mm.

[0027] Step 2: Start the cooling system, monitor the temperature of different parts of the ingot mold, and sequentially implement the following cooling operations:

[0028] Step 21, first open the first layer nozzle 221, and use the spray from the first layer nozzle 221 to cool the ingot mold for 3.5 min; then open the second layer nozzle 222, and use the spray from the second layer nozzle 222 to cool the ingot mold for 3.5 min… until the sixth layer (top layer) nozzle is opened to spray the ingot mold for cooling; wherein the spray pressure of each layer of nozzle is controlled to be 1 bar, and the flow rate is controlled to be 400 mL / min.

[0029] Step 22, adjust the flow rate of the first layer nozzle 221, and use the spray from the first layer nozzle 221 to cool the ingot mold for 2.5 min; then adjust the flow rate of the second layer nozzle 222, and use the spray from the second layer nozzle 222 to cool the ingot mold for 2.5 min… until the sixth layer (top layer) nozzle is opened to spray the ingot mold for cooling; wherein the spray pressure of each layer of nozzle is controlled to be 4 bar, and the flow rate is controlled to be 1000 mL / min.

[0030] Step 3, open the water inlet valve 25, and make the water level in the cooling chamber 2 rise at a speed of 90 mm / min. Whenever the water level reaches the height of each layer of nozzles, close all the nozzles of that layer. Until the water level reaches the top of the cooling chamber 2, open the drain valve 26, and quickly adjust the water flow rate to make the water inlet amount equal to the water outlet amount.

[0031] Step 4, when the temperature of the ingot is lower than 200℃, close the water inlet valve 25. After the water in the cooling chamber 2 is drained, take out the ingot, rinse it with water for 3-5 min, and then air cool it to room temperature.

[0032] Example 2

[0033] In combination Figure 1 As shown in the figure, a large-size magnesium alloy ingot preparation method is used to prepare a WE43 magnesium alloy ingot with a diameter of Ф1500 mm and a height of 1500 mm. The steps include:

[0034] Step 1, after the alloy melt reaches the pouring temperature of 705℃, first introduce a protective atmosphere into the bottom of the preheated ingot mold to 340℃, and the protective atmosphere used is 70% Ar + 30% CO2. Then, through the pipeline 5, the alloy melt is delivered to the ingot mold. After pouring is completed, the top of the mold is covered with thermal insulation cotton.

[0035] The ingot casting mold comprises a cavity 1, temperature monitoring points are arranged on the ingot casting mold, and a circumferential cooling system is arranged on the outer periphery of the cavity 1; the circumferential cooling system comprises a cooling chamber 2, eight layers of nozzles 22 are arranged in the cooling chamber 2 from top to bottom at intervals, the height difference between adjacent layers of nozzles 22 is 150 mm, fourteen nozzles 22 are uniformly arranged in each layer, nozzles are not arranged in the top 300 mm of the ingot casting mold, the height covered by all the nozzles 22 is not less than the height of the melt filled in the cavity 1, each layer of horizontally arranged nozzles 22 is connected with a water inlet pipe 21, the water inlet pipe 21 is connected with a fluid medium supply system, a water inlet valve 25 is arranged on the water inlet pipe 21, a water outlet valve 26 is arranged on the liquid discharge pipe section of the circumferential cooling system, and the water inlet pipe 21 is located between the first layer of nozzles 221 and the liquid discharge pipe;

[0036] The lower section 4 of the pipeline is in a serpentine structure and arranged vertically, the length of the lower section 4 (i.e. the serpentine structure) is equal to half the height of the cavity, the lower section 4 is close to the bottom of the side wall of the cavity 1, the outlet of the lower section 4 horizontally faces the side wall of the cavity 1, and the radius of the arc-shaped part of the lower section 4 is 55 mm;

[0037] Step 2, start the cooling system, monitor the temperature of different parts of the ingot casting mold, and sequentially implement the following cooling operations:

[0038] Step 21, first open the first layer of nozzles 221, use the spray of the first layer of nozzles 221 to cool the ingot casting mold for 4 min, then open the second layer of nozzles 222, use the spray of the second layer of nozzles 222 to cool the ingot casting mold for 4 min, and so on until the eighth layer (top layer) of nozzles is opened to spray and cool the ingot casting mold; wherein the spray pressure of each layer of nozzles is controlled to be 1 bar, and the flow is controlled to be 300 mL / min.

[0039] Step 22, adjust the flow of the first layer of nozzles 221, use the spray liquid of the first layer of nozzles 221 to cool the ingot casting mold for 3 min, then adjust the flow of the second layer of nozzles 222, use the spray liquid of the second layer of nozzles 222 to cool the ingot casting mold for 3 min, and so on until the eighth layer (top layer) of nozzles is opened to spray and cool the ingot casting mold; wherein the spray liquid pressure of each layer of nozzles is controlled to be 4 bar, and the flow is controlled to be 800 mL / min.

[0040] Step 3, open the water inlet valve 25, and make the water level in the cooling chamber 2 rise at a speed of 85 mm / min, whenever the water level reaches the height of each layer of nozzles, close all the nozzles of the layer, until the water level reaches the top of the cooling chamber 2, open the water outlet valve 26, and quickly adjust the water flow to make the water inlet amount equal to the water outlet amount;

[0041] Step 4, when the ingot temperature is lower than 200℃, close the water inlet valve 25, after the water in the cooling chamber 2 is exhausted, take out the ingot, rinse with water for 4-5min, and then air cool to room temperature.

[0042] Example 3

[0043] Combined Figure 1 As shown in the figure, a large-size magnesium alloy ingot preparation method is used to prepare a VW84 magnesium alloy ingot with a diameter of Ф2000mm and a height of 2200mm, and the steps include:

[0044] Step 1, after the alloy melt reaches the pouring temperature of 710℃, first introduce a protective atmosphere into the bottom of the preheated ingot mold to 350℃, and the protective atmosphere used is 70% Ar+30% CO2, then the alloy melt is transported into the ingot mold through the pipeline 5, and after pouring is completed, the top of the mold is covered with heat preservation cotton;

[0045] The ingot mold includes a cavity 1, and the ingot mold is provided with a temperature monitoring point, and a circumferential cooling system is arranged outside the cavity 1; the circumferential cooling system includes a cooling chamber 2, twelve layers of nozzles 22 are arranged in the cooling chamber 2 from top to bottom, the height difference between adjacent layers of nozzles 22 is 150mm, eighteen nozzles 22 are uniformly arranged in each layer, nozzles are not arranged in the top 300mm height of the ingot mold, the height covered by all the nozzles 22 is not less than the height of the melt filled in the cavity 1, each layer of horizontally arranged nozzles 22 is connected with a water inlet pipe 21, the water inlet pipe 21 is connected with a fluid medium supply system, a water inlet valve 25 is arranged on the water inlet pipe 21, a drain valve 26 is arranged on the drain pipe section of the circumferential cooling system, and the water inlet pipe 21 is located between the first layer of nozzles 221 and the drain pipe;

[0046] The lower section 4 of the pipeline is in a serpentine structure and arranged vertically, the length of the lower section 4 (i.e. the serpentine structure) is equal to half the height of the cavity, the lower section 4 of the pipeline is close to the bottom of the side wall of the cavity 1, the outlet of the lower section 4 of the pipeline horizontally faces the side wall of the cavity 1, and the radius of the arc-shaped part of the lower section 4 of the pipeline is 60mm;

[0047] Step 2, start the cooling system, monitor the temperature of different parts of the ingot mold, and sequentially implement the following cooling operations:

[0048] Step 21, first open the first layer of nozzles 221, use the spray jet of the first layer of nozzles 221 to cool the ingot mold for 4min; then open the second layer of nozzles 222, use the spray jet of the second layer of nozzles 222 to cool the ingot mold for 4min…… until the twelfth layer (top layer) of nozzles is opened to spray and cool the ingot mold; wherein the spray pressure of each layer of nozzles is controlled to be 2bar, and the flow rate is controlled to be 500mL / min.

[0049] Step 22, adjust the flow of the first layer of nozzles 221, and use the sprayed liquid sprayed by the first layer of nozzles 221 to cool the ingot mold for 2 minutes; then adjust the flow of the second layer of nozzles 222, and use the sprayed liquid sprayed by the second layer of nozzles 222 to cool the ingot mold for 2 minutes... until the twelfth layer (top layer) nozzle is opened to spray and cool the ingot mold; wherein the pressure of the sprayed liquid of each layer of nozzles is controlled at 4 bar, and the flow is controlled at 1200 mL / min.

[0050] Step 3, open the water inlet valve 25, and make the water level in the cooling chamber 2 rise at a speed of 100 mm / min. Whenever the water level reaches the height of each layer of nozzles, close all the nozzles of that layer, until the water level reaches the top of the cooling chamber 2, open the drain valve 26, and quickly adjust the water flow to make the water inlet equal to the water outlet;

[0051] Step 4, when the temperature of the ingot is lower than 200℃, close the water inlet valve 25, and after the water in the cooling chamber 2 is drained, take out the ingot, rinse it with water for 4-5 minutes, and then air cool it to room temperature.

[0052] Comparative Example 1: AZ80 magnesium alloy ingots with a diameter of Ф800 mm and a height of 1200 mm were prepared. After the alloy melt reached the pouring temperature of 700℃, a protective atmosphere was first introduced into the bottom of the ingot mold, and the protective atmosphere used was 70% Ar + 30% CO2. Then the alloy melt was transported to the ingot mold through a pipeline (the lower section of the pipeline is a straight section). After pouring, the top of the mold was covered with insulation cotton, and then four evenly arranged water spray guns were used to spray the ingot mold from bottom to top simultaneously. The pressure during spraying was controlled at 4 bar, and the flow was controlled at 1000 mL / min.

[0053] Comparative Example 2: WE43 magnesium alloy ingots with a diameter of Ф1500 mm and a height of 1500 mm were prepared. After the alloy melt reached the pouring temperature of 705℃, a protective atmosphere was first introduced into the bottom of the ingot mold, and the protective atmosphere used was 70% Ar + 30% CO2. Then the alloy melt was transported to the ingot mold through a pipeline (the lower section of the pipeline is a serpentine structure with a radius of 55 mm in the arc region). After pouring, the top of the mold was covered with insulation cotton, and then six evenly arranged water spray guns were used to spray the ingot mold from bottom to top simultaneously. The pressure during spraying was controlled at 4 bar, and the flow was controlled at 800 mL / min.

[0054] The material utilization of the large-size magnesium alloy ingot prepared in Example 1, Example 2, Example 3 and Comparative Example was evaluated, and the top of the ingot with defects such as loose shrinkage, porosity, cracks, cracking and the like was defined as an unqualified segment, and the top of the ingot without defects such as loose shrinkage, porosity, cracks, cracking and the like was defined as a qualified segment, and the ingot of the unqualified segment could not be utilized, and the ingot of the qualified segment could be utilized. The results showed that the length of the unqualified segment of the top of the large-size magnesium alloy ingot obtained in Example 1 was 65 mm, the length of the unqualified segment of the top of the large-size magnesium alloy ingot obtained in Comparative Example 1 was 135 mm, the length of the unqualified segment of the top of the large-size magnesium alloy ingot obtained in Example 2 was 79 mm, the length of the unqualified segment of the top of the large-size magnesium alloy ingot obtained in Comparative Example 2 was 121 mm, and the length of the unqualified segment of the top of the large-size magnesium alloy ingot obtained in Example 3 was 92 mm.

[0055] The large-size magnesium alloy ingots prepared in Example 1, Example 2 and Example 3 (except for the unqualified segment of the top of the magnesium alloy ingot) were detected, and the results showed that the magnesium alloy ingot obtained in Example 1 was A grade, the magnesium alloy ingot obtained in Example 2 was A grade, and the magnesium alloy ingot obtained in Example 3 was A grade (all according to the A grade technical requirements of GB / T6519-2013 standard).

[0056] By using the scheme in the examples, not only the material utilization in the preparation process of the large-size magnesium alloy ingot is greatly improved, but also the production cost of the large-size magnesium alloy ingot is significantly reduced (the main cost except for the mold comes from the circumferential cooling system, the required equipment cost is very low, and a large number of tooling fixtures are saved), and the casting defects such as gas entrapment and pinhole of the melt in the pouring process of the large-size ingot can be effectively avoided; the scheme effectively solves the serious quality problems such as loose shrinkage of the large-size ingot, and prevents the problems such as heart cracking of the ingot caused by excessive cooling intensity, and the obtained large-size ingot has a dense structure. More importantly, the scheme can realize the continuous batch production of the large-size magnesium alloy ingot with extremely simple equipment, and the corresponding equipment can be repeatedly used and has good versatility, and can be shared by multiple molds.

Claims

1. A method for producing a large-size magnesium alloy ingot, characterized by the steps of The application relates to a method for preparing a high-purity aluminum alloy ingot. The ingot mold comprises a cavity (1), and temperature monitoring points are arranged on the ingot mold; a circumferential cooling system is arranged outside the cavity (1); the circumferential cooling system comprises a cooling chamber (2), a plurality of layers of nozzles (22) are arranged in the cooling chamber (2) from top to bottom at intervals, the height covered by all the nozzles (22) is not less than the height of the melt filled in the cavity (1), each layer of the horizontally arranged nozzles (22) is connected with a water inlet pipe (21), the water inlet pipe (21) is connected with a fluid medium supply system, a water inlet valve (25) is arranged on the water inlet pipe (21), and a water outlet valve (26) is arranged on the liquid discharge pipe section of the circumferential cooling system. Step 2: the cooling system is started, the temperature of different parts of the ingot mold is monitored, and the following cooling operations are sequentially implemented: Step 21: first, the first layer of nozzles (221) is opened, the spray jet of the first layer of nozzles (221) is used to cool the ingot mold for 3-5 min; then, the second layer of nozzles (222) is opened, the spray jet of the second layer of nozzles (222) is used to cool the ingot mold for 3-5 min, and the process is repeated until the top layer of nozzles is opened to spray and cool the ingot mold. Step 22: the flow of the first layer of nozzles (221) is adjusted, the spray jet of the first layer of nozzles (221) is used to cool the ingot mold for 2-3 min; then, the flow of the second layer of nozzles (222) is adjusted, the spray jet of the second layer of nozzles (222) is used to cool the ingot mold for 2-3 min, and the process is repeated until the top layer of nozzles is opened to spray and cool the ingot mold. Step 3: the water inlet valve (25) is opened, the water level in the cooling chamber (2) is raised at a speed of 80-100 mm / min, when the water level reaches the height of each layer of nozzles, all the nozzles of the layer are closed, until the water level reaches the top of the cooling chamber (2), the water outlet valve (26) is opened, and the water flow is quickly adjusted so that the water inlet flow is equal to the water outlet flow. Step 4: when the temperature of the ingot is lower than 200 DEG C, the water inlet valve (25) is closed, the ingot is taken out after the water in the cooling chamber (2) is discharged, the ingot is washed with water for 3-5 min, and then the ingot is air-cooled to room temperature. The protective atmosphere used in step 1 is 70% Ar+30% CO2.

2. The magnesium alloy ingot production method according to claim 1, characterized by: The lower segment (4) of the pipeline (5) in the cavity (1) is in a serpentine structure and vertically arranged.

3. The magnesium alloy ingot production method according to any one of claims 1 to 2, characterized by: The lower segment (4) of the pipeline (5) is close to the bottom of the side wall of the cavity (1), and the outlet of the lower segment (4) of the pipeline (5) horizontally faces the side wall of the cavity (1).

4. The magnesium alloy ingot production method according to claim 3, characterized by: The radius of the arc-shaped part of the lower segment (4) of the pipeline (5) is 40-70 mm.

5. The magnesium alloy ingot production method according to claim 4, characterized by: The water inlet pipe (21) is located between the first layer of nozzles (221) and the liquid discharge pipe.

6. The magnesium alloy ingot production method according to claim 5, characterized by: ​

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