Refining and degassing process for aluminum ingot melting

Abstract

The invention discloses a refining degassing process for aluminum ingot melting, which belongs to the technical field of aluminum ingot refining processing, and comprises the following steps: (1) aluminum ingot melting, (2) refining agent and alterant treatment, (3) refining agent addition, and (4) alterant addition. The treatment process is simple in step and reasonable in matching, the strength and hardness of the aluminum ingot are effectively improved, the possibility of cracking of a later finished product is reduced, elimination of thermodynamic activity in an aluminum alloy liquid can be promoted, chemical reaction is promoted, and therefore the purpose of improving purity and uniformity is achieved.

Description

Technical Field

[0001] The invention belongs to the technical field of aluminum ingot refining and processing, in particular to a refining and degassing process for aluminum ingot melting. Background Art

[0002] The main purpose of aluminum ingot refining and degassing is to remove gases and oxide inclusions in the aluminum melt to improve the purity and performance of the aluminum melt. If these gases and inclusions remain in the aluminum melt, it will cause product leakage, easy corrosion, and significantly reduce the mechanical properties. At the same time, it will also reduce the fluidity of the alloy and bring difficulties to casting. The traditional refining method will reduce the purity of the aluminum ingot and will cause the product itself to have loose quality problems, affecting the subsequent processing effect. Summary of the invention

[0003] The purpose of the present invention is to provide a refining and degassing process for melting aluminum ingots to solve the deficiencies in the prior art.

[0004] The technical solution adopted by the present invention is as follows: A refining and degassing process for melting aluminum ingots comprises the following steps: (1) Melting of aluminum ingots: After removing the aluminum rust, oil stains and dust on the surface of the aluminum ingot, the aluminum ingot is kept warm in a vacuum melting furnace and then water quenched. The water-quenched aluminum ingot is taken out and added to the melting furnace for melting; (2) Treatment of refining agents and modifiers: The solid refining agent and the modifier are kept warm in an oven to remove moisture; (3) Addition of refining agent: In step (1), the temperature of the aluminum ingot is controlled at 700-720 degrees Celsius, and the refining agent is added to the aluminum in equal amounts according to the number of times, and the time interval between each addition of the refining agent is 18-25 minutes. After each addition of the refining agent, auxiliary refining gas is passed into the aluminum liquid for 5-10 minutes. After the last auxiliary refining gas is passed for 15-20 minutes, the smelting temperature is maintained at 730-745 degrees Celsius for refining, and the slag is removed after the refining is completed; (4) Addition of deteriorating agent: After adding the modifier to the aluminum liquid in step (3), let it stand for 18-22 minutes to allow the ash to settle. After cleaning, cool it and then cast it.

[0005] Furthermore, the water quenching temperature of the aluminum ingot in step (1) is controlled at 95-98 degrees Celsius.

[0006] Furthermore, the treatment oven for the refining agent and the modifier in step (2) is kept warm at a temperature of 245-255 degrees Celsius for 3.5 hours.

[0007] Furthermore, the refining agent in step (3) is added 4-5 times.

[0008] Furthermore, in step (3), the auxiliary refining gas composition is chlorine: hexafluoroethane: nitrogen = 6-8: 6-8: 72-76.

[0009] Furthermore, during the process of introducing the auxiliary refining gas in step (3), the aluminum liquid can be stirred by a rotor, the rotor speed is 520-550 r / min, the introduction flow rate of the auxiliary refining gas is 30-35 L / min, and the pressure is 0.8-1 MPa.

[0010] The present invention has the following beneficial effects: The treatment process of the present invention is simple, and the physical and mechanical properties of the aluminum ingot can be improved by water quenching the aluminum ingot, and its strength, hardness and corrosion resistance can be improved. Water quenching can make the structure of the aluminum ingot dense and the grains refined. These improved structures and grains help to improve the strength and hardness of the aluminum ingot and reduce the possibility of cracking of the finished product in the later stage. By adding the refining agent in batches and accompanying the introduction of auxiliary refining gas, the complementary effect of the two can remove gas impurities and improve the oxidation stability of the aluminum alloy, and can also promote the elimination of thermodynamically active substances in the liquid state of the aluminum alloy and promote chemical reactions, thereby achieving the purpose of improving purity and uniformity. DETAILED DESCRIPTION

[0011] The following will be described clearly and completely in conjunction with the technical solutions of the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0012] A refining and degassing process for melting aluminum ingots comprises the following steps: (1) Melting of aluminum ingots: After removing the aluminum rust, oil stains and dust on the surface of the aluminum ingot, the aluminum ingot is kept warm in a vacuum melting furnace and then water quenched. The water-quenched aluminum ingot is taken out and added to the melting furnace for melting; (2) Treatment of refining agents and modifiers: The solid refining agent and the modifier are kept warm in an oven to remove moisture; (3) Addition of refining agent: In step (1), the temperature of the aluminum ingot is controlled at 700-720 degrees Celsius, and the refining agent is added to the aluminum in equal amounts according to the number of times, and the time interval between each addition of the refining agent is 18-25 minutes. After each addition of the refining agent, auxiliary refining gas is passed into the aluminum liquid for 5-10 minutes. After the last auxiliary refining gas is passed for 15-20 minutes, the smelting temperature is maintained at 730-745 degrees Celsius for refining, and the slag is removed after the refining is completed; (4) Addition of deteriorating agent: After adding the modifier to the aluminum liquid in step (3), let it stand for 18-22 minutes to allow the ash to settle. After cleaning, cool it and then cast it.

[0013] The water quenching temperature of the aluminum ingot described in step (1) is controlled at 95-98 degrees Celsius.

[0014] The treatment oven for the refining agent and the modifier described in step (2) is kept warm at a temperature of 245-255 degrees Celsius for 3.5 hours.

[0015] The refining agent in step (3) is added 4-5 times.

[0016] The auxiliary refining gas composition in step (3) is chlorine: hexafluoroethane: nitrogen = 6-8: 6-8: 72-76.

[0017] During the process of introducing the auxiliary refining gas in step (3), the aluminum liquid can be stirred by the rotor, the rotation speed of the rotor is 520-550r / min, the introduction flow rate of the auxiliary refining gas is 30-35L / min, and the pressure is 0.8-1MPa. Example 1

[0018] A refining and degassing process for melting aluminum ingots comprises the following steps: (1) Melting of aluminum ingots: After removing the aluminum rust, oil stains and dust on the surface of the aluminum ingot, the aluminum ingot is kept warm in a vacuum melting furnace and then water quenched. The water-quenched aluminum ingot is taken out and added to the melting furnace for melting; (2) Treatment of refining agents and modifiers: The solid refining agent and the modifier are kept warm in an oven to remove moisture; (3) Addition of refining agent: In step (1), the temperature of the aluminum ingot is controlled at 700 degrees Celsius, and the refining agent is added to the aluminum in equal amounts according to the number of times. The time interval between each addition of the refining agent is 18 minutes. After each addition of the refining agent, an auxiliary refining gas is passed into the aluminum liquid for 5 minutes. After the last auxiliary refining gas is passed for 15 minutes, the smelting temperature is maintained at 730 degrees Celsius for refining. After the refining is completed, the slag is removed; (4) Addition of deteriorating agent: After adding the modifier to the aluminum liquid in step (3), let it stand for 18 minutes to allow the ash to settle. After cleaning, cool it and then cast it.

[0019] The water quenching temperature of the aluminum ingot in step (1) is controlled at 95 degrees Celsius.

[0020] The treatment oven for the refining agent and the modifier in step (2) is kept warm at a temperature of 245 degrees Celsius for 3.5 hours.

[0021] The refining agent in step (3) is added four times.

[0022] The auxiliary refining gas composition in step (3) is chlorine: hexafluoroethane: nitrogen = 6:6:72.

[0023] During the introduction of the auxiliary refining gas in step (3), the aluminum liquid can be stirred by the rotor, the rotor speed is 520r / min, the introduction rate of the auxiliary refining gas is 30L / min, and the pressure is 0.8MPa. Example 2

[0024] A refining and degassing process for melting aluminum ingots comprises the following steps: After removing the aluminum rust, oil stains and dust on the surface of the aluminum ingot, the aluminum ingot is kept warm in a vacuum melting furnace and then water quenched. The water-quenched aluminum ingot is taken out and added to the melting furnace for melting; (2) Treatment of refining agents and modifiers: The solid refining agent and the modifier are kept warm in an oven to remove moisture; (3) Addition of refining agent: In step (1), the temperature of the aluminum ingot is controlled at 710 degrees Celsius, and the refining agent is added to the aluminum in equal amounts according to the number of times. The time interval between each addition of the refining agent is 20 minutes. After each addition of the refining agent, auxiliary refining gas is passed into the aluminum liquid for 7 minutes. After the last auxiliary refining gas is passed for 18 minutes, the smelting temperature is maintained at 740 degrees Celsius for refining. After the refining is completed, the slag is removed; (4) Addition of deteriorating agent: After adding the modifier to the aluminum liquid in step (3), let it stand for 18 minutes to allow the ash to settle. After cleaning, cool it and then cast it.

[0025] The water quenching temperature of the aluminum ingot in step (1) is controlled at 96 degrees Celsius.

[0026] The treatment oven for the refining agent and the modifier in step (2) is kept warm at a temperature of 250 degrees Celsius for a time of 3.5 hours.

[0027] The refining agent in step (3) is added 5 times.

[0028] The auxiliary refining gas composition in step (3) is chlorine: hexafluoroethane: nitrogen = 7:7:74.

[0029] During the introduction of the auxiliary refining gas in step (3), the aluminum liquid can be stirred by a rotor, the rotor speed is 535 r / min, the introduction flow rate of the auxiliary refining gas is 33 L / min, and the pressure is 0.9 MPa. Example 3

[0030] A refining and degassing process for melting aluminum ingots comprises the following steps: (1) Surface degreasing and cleaning: After removing the aluminum rust, oil stains and dust on the surface of the aluminum ingot, the aluminum ingot is kept warm in a vacuum melting furnace and then water quenched. The water-quenched aluminum ingot is taken out and added to the melting furnace for melting; (2) Treatment of refining agents and modifiers: The solid refining agent and the modifier are kept warm in an oven to remove moisture; (3) Addition of refining agent: In step (1), the temperature of the aluminum ingot is controlled at 720 degrees Celsius, and the refining agent is added to the aluminum in equal amounts according to the number of times. The time interval between each addition of the refining agent is 25 minutes. After each addition of the refining agent, an auxiliary refining gas is passed into the aluminum liquid for 10 minutes. After the last auxiliary refining gas is passed for 25 minutes, the melting temperature is maintained at 745 degrees Celsius for refining. After the refining is completed, the slag is removed; (4) Addition of modifiers: After adding the modifier to the aluminum liquid in step (3), let it stand for 22 minutes to allow the ash to settle. After cleaning, cool it and then cast it.

[0031] The water quenching temperature of the aluminum ingot in step (1) is controlled at 98 degrees Celsius.

[0032] The treatment oven for the refining agent and the modifier in step (2) is kept warm at a temperature of 255 degrees Celsius for a time of 3.5 hours.

[0033] The refining agent in step (3) is added 5 times.

[0034] The auxiliary refining gas composition in step (3) is chlorine: hexafluoroethane: nitrogen = 8:8:76.

[0035] During the introduction of the auxiliary refining gas in step (3), the aluminum liquid can be stirred by a rotor, the rotor speed is 550 r / min, the introduction flow rate of the auxiliary refining gas is 35 L / min, and the pressure is 1.0 MPa.

[0036] Comparative Example 1 Compared with Example 1, in the melting of the aluminum ingot, the water quenching process of step (1) is omitted in this comparative example 1, and other method steps are the same.

[0037] Comparative Example 2 Compared with Example 2, in the treatment of (2) refining agent and modifier, the heat preservation treatment is omitted in this comparative example 2, and other method steps are the same.

[0038] Comparative Example 3 Compared with Example 2, the comparative example 3 omits step (3) of introducing the auxiliary refining gas, and other method steps are the same.

[0039] In order to compare the effect of the present invention, a quick analysis was performed by atomic absorption method after sampling and it was found that the aluminum ingot prepared in the embodiment had high purity and the product stability of the aluminum alloy product was relatively high.

[0040] Therefore, the purity of the aluminum ingots after treatment by the present invention is improved, and the possibility of cracking of the finished product in the later stage is reduced, which provides a new treatment method for enhancing the quality of aluminum ingot materials and has great promotion and application value.

[0041] The above description is only a preferred embodiment of the present invention, but the present invention is not limited to the scope of implementation shown. Any changes made in accordance with the concept of the present invention, or modifications to equivalent embodiments with equivalent changes, which still do not exceed the spirit covered by the specification, should be within the protection scope of the present invention.

Claims

1. A refining and degassing process for melting aluminum ingots, characterized in that: The steps include: (1) Melting of aluminum ingots: After removing the aluminum rust, oil stains and dust on the surface of the aluminum ingot, the aluminum ingot is kept warm in a vacuum melting furnace and then water quenched. The water-quenched aluminum ingot is taken out and added to the melting furnace for melting; (2) Treatment of refining agents and modifiers: The solid refining agent and the modifier are kept warm in an oven to remove moisture; (3) Addition of refining agent: In step (1), the temperature of the aluminum ingot is controlled at 700-720 degrees Celsius, and the refining agent is added to the aluminum in equal amounts according to the number of times, and the time interval between each addition of the refining agent is 18-25 minutes. After each addition of the refining agent, auxiliary refining gas is passed into the aluminum liquid for 5-10 minutes. After the last auxiliary refining gas is passed for 15-20 minutes, the smelting temperature is maintained at 730-745 degrees Celsius for refining, and the slag is removed after the refining is completed; (4) Addition of deteriorating agent: After adding the modifier to the aluminum liquid in step (3), let it stand for 18-22 minutes to allow the ash to settle. After cleaning, cool it and then cast it.

2. A refining and degassing process for melting aluminum ingots according to claim 1, characterized in that: The water quenching temperature of the aluminum ingot described in step (1) is controlled at 95-98 degrees Celsius.

3. A refining and degassing process for melting aluminum ingots according to claim 1, characterized in that: The treatment oven for the refining agent and the modifier described in step (2) is kept warm at a temperature of 245-255 degrees Celsius for 3.5 hours.

4. A refining and degassing process for melting aluminum ingots according to claim 1, characterized in that: The refining agent in step (3) is added 4-5 times.

5. A refining and degassing process for melting aluminum ingots according to claim 1, characterized in that: The auxiliary refining gas composition in step (3) is chlorine: hexafluoroethane: nitrogen = 6-8: 6-8: 72-76.

6. A refining and degassing process for melting aluminum ingots according to claim 1, characterized in that: During the process of introducing the auxiliary refining gas in step (3), the aluminum liquid can be stirred by the rotor, the rotation speed of the rotor is 520-550r / min, the introduction flow rate of the auxiliary refining gas is 30-35L / min, and the pressure is 0.8-1MPa.