A method for efficiently preparing beryllium copper master alloy

Abstract

The present invention belongs to the technical field of metal material manufacturing, and specifically relates to a method for efficiently preparing beryllium copper master alloy. The preparation method is to mix BeO powder and flake graphite powder evenly, and obtain beryllium copper master alloy ingot after vacuum melting and vacuum casting with electrolytic copper plate, and then the beryllium copper master alloy ingot is subjected to vacuum consumable melting to obtain beryllium copper master alloy. The present invention can avoid the harm caused to human body and environment by beryllium-containing dust and smoke generated in the production process, and can significantly reduce the oxygen, other gas content and inclusion content of the beryllium copper master alloy. The present invention has short process flow, high production efficiency and large output, and can produce beryllium copper master alloy of 1.5T-3.2T weight at one time, and the beryllium copper product has high quality and is easy to industrialize.

Description

Technical Field

[0001] The invention belongs to the technical field of metal material manufacturing, and in particular relates to a method for efficiently preparing a beryllium copper master alloy. Background Art

[0002] Beryllium copper alloy contains 0.2% to 2.8% beryllium, and has the advantages of high strength, high conductivity, high toughness, high fatigue limit, high wear resistance, seawater corrosion resistance, non-magnetic, heat shock resistance, no sparks when collision, etc., and is widely used in electrical equipment, electronic devices and control instruments. At present, the preparation of beryllium copper alloy generally uses beryllium copper master alloy plus electrolytic copper and other metal elements to smelt to obtain beryllium copper alloy with a beryllium content of 0.2% to 2.8%. Therefore, the quality and production cost of beryllium copper master alloy will seriously affect the quality and price of beryllium copper alloy.

[0003] Chinese patent CN103866155A discloses a "beryllium copper alloy production and ingot casting process", which uses copper, beryllium oxide and carbon black in a certain ratio as raw materials, uses an electric arc furnace to melt the ingots, and then uses a medium frequency furnace to melt and cast. However, its disadvantage is that the melting process is not vacuum melting, and the gas generated during melting will remain inside the beryllium copper alloy. Chinese patent CN113088752A discloses "a method for preparing beryllium copper master alloy", which adopts vacuum consumable arc melting to prepare beryllium copper master alloy, firstly coating beryllium oxide powder, then mixing beryllium oxide powder, copper powder and graphite powder evenly to obtain mixed powder; then pressing the mixed powder to obtain slab; then rolling the slab to obtain fragments, crushing to obtain blank powder with a particle size not exceeding 1 mm; after annealing the blank powder, adding paraffin powder, mixing evenly, and then pressing to obtain a columnar green billet; loading the columnar green billet into a graphite mold, sintering, demoulding, and obtaining a working electrode; then loading the working electrode into a vacuum consumable arc furnace, performing vacuum consumable electrode arc melting, and obtaining a beryllium copper master alloy, but its production process is long, the process is complicated, and the production cost is high. Summary of the invention

[0004] In view of the above-mentioned deficiencies in the prior art, the object of the present invention is to provide a method for efficiently preparing beryllium copper master alloy.

[0005] To achieve the above objectives, the technical solutions adopted are:

[0006] A method for efficiently preparing beryllium copper master alloy comprises the following steps:

[0007] (1) Adding materials: beryllium oxide and flake graphite powder are mixed at a molar ratio of 1.1-1.3:1 to obtain beryllium oxide flake graphite powder, an electrolytic copper plate is placed in a crucible, and the mixed beryllium oxide flake graphite powder is placed in a proportion;

[0008] (2) Vacuum smelting: After adding materials, the smelting chamber is closed and evacuated to 5-10Pa. The temperature is raised at the same time until the temperature in the furnace reaches 1950-2100°C and kept warm for 2-3 hours. During the warming process, a graphite rod is used to stir the molten copper to allow the flake graphite powder to fully mix and react with beryllium oxide, reduce and deoxidize, and also allow the generated slag to float;

[0009] (3) Vacuum casting: During the vacuum melting and vacuum casting process, the pressure in the melting chamber and the casting chamber is kept at 5-10Pa. When the temperature of the copper liquid drops to 1200-1300°C, casting is performed. After the casting is completed, the ingot is completely solidified and then the vacuum is broken and taken out;

[0010] (4) Vacuum consumable smelting: The obtained ingot is subjected to vacuum consumable smelting to obtain beryllium copper master alloy.

[0011] Furthermore, the copper content of the electrolytic copper plate in step (1) is 99.99%, and the electrolytic copper plate and beryllium oxide flake graphite powder are mixed in a proportion such that the mass content of the beryllium element accounts for 4-8% of the total mass of the beryllium element and the copper element.

[0012] Furthermore, the working voltage of the vacuum consumable melting in step (4) is 27-35V, the current is 10000-13000A, the vacuum degree is 0.1Pa-2Pa, and the feed speed of the working electrode is 10-20mm / min.

[0013] Furthermore, the weight of the beryllium copper master alloy is 1.5T-3.2T.

[0014] Compared with the prior art, the present invention has the following beneficial effects:

[0015] The present invention adopts a combined process of vacuum melting, vacuum casting and vacuum consumable refining, which can avoid the harm of beryllium dust and smoke generated in the production process to the human body and the environment. At the same time, the present invention has high production efficiency and large output, and can produce 1.5T-3.2T of beryllium copper master alloy at one time. Through the combined process of vacuum melting, vacuum casting and vacuum consumable refining, the content of oxygen, other gases and inclusions inside the beryllium copper master alloy can be significantly reduced. The present invention has a short process flow, high production efficiency, high quality beryllium copper products, and is easy to industrialize. DETAILED DESCRIPTION

[0016] The present invention is described below in conjunction with examples, which are only used to explain the present invention and are not used to limit the scope of the present invention.

[0017] Example 1

[0018] (1) Adding materials: beryllium oxide and flake graphite powder are mixed in a molar ratio of 1.1:1 to obtain beryllium oxide flake graphite powder, an electrolytic copper plate with a purity of 99.99% is placed in a crucible, and the mixed beryllium oxide flake graphite powder is placed in a proportion, wherein the electrolytic copper plate and the beryllium oxide flake graphite powder are mixed in a proportion such that the mass content of the beryllium element accounts for 4% of the total mass of the beryllium element and the copper element;

[0019] (2) Vacuum smelting: After adding materials, the smelting chamber is closed and evacuated to 5 Pa. At the same time, power is supplied to increase the temperature until the temperature in the furnace reaches 2000°C and the temperature is kept for 2 hours. During the heat preservation process, a graphite rod is used to stir the smelted copper liquid so that the flake graphite powder is fully mixed with beryllium oxide for reaction, reduction and deoxidation, and the generated slag floats;

[0020] (3) Vacuum casting: During the smelting and casting process, the pressure in the smelting chamber and the casting chamber is kept at 5 Pa. When the temperature of the molten copper drops to 1200°C, casting is performed. After the casting is completed, the ingot is completely solidified and then the vacuum is broken and taken out;

[0021] (4) Vacuum consumable melting: The obtained ingot is subjected to vacuum consumable melting. The working voltage of the vacuum consumable melting is 30 V, the current is 11000 A, the vacuum degree is 1 Pa, and the feed speed of the working electrode is 15 mm / min, thereby obtaining beryllium copper master alloy.

[0022] Example 2

[0023] (1) Adding materials: beryllium oxide and flake graphite powder are mixed in a molar ratio of 1.3:1 to obtain beryllium oxide flake graphite powder, an electrolytic copper plate with a purity of 99.99% is placed in a crucible, and the mixed beryllium oxide flake graphite powder is placed in a proportion, wherein the electrolytic copper plate and the beryllium oxide flake graphite powder are mixed in a proportion such that the mass content of the beryllium element accounts for 4% of the total mass of the beryllium element and the copper element;

[0024] (2) Vacuum smelting: After adding materials, the smelting chamber is closed and evacuated to 10Pa. At the same time, power is supplied to increase the temperature until the temperature in the furnace reaches 2100°C and the temperature is kept for 2 hours. During the heat preservation process, a graphite rod is used to stir the smelted copper liquid so that the flake graphite powder is fully mixed with beryllium oxide for reaction, reduction and deoxidation, and the generated slag floats;

[0025] (3) Vacuum casting: During the smelting and casting process, the pressure in the smelting chamber and the casting chamber is kept at 10Pa. When the temperature of the molten copper drops to 1200°C, casting is performed. After the casting is completed, the ingot is completely solidified and then the vacuum is broken and taken out;

[0026] (4) Vacuum consumable melting: The obtained ingot is subjected to vacuum consumable melting. The working voltage of the vacuum consumable melting is 35V, the current is 13000A, the vacuum degree is 2Pa, and the feed speed of the working electrode is 20mm / min, so as to obtain beryllium copper master alloy.

[0027] Comparative Example 1

[0028] (1) Adding materials: beryllium oxide and flake graphite powder are mixed in a molar ratio of 1.1:1 to obtain beryllium oxide flake graphite powder, an electrolytic copper plate with a purity of 99.99% is placed in a crucible, and the mixed beryllium oxide flake graphite powder is placed in a proportion, wherein the electrolytic copper plate and the beryllium oxide flake graphite powder are mixed in a proportion such that the mass content of the beryllium element accounts for 4% of the total mass of the beryllium element and the copper element;

[0029] (2) Vacuum smelting: After adding materials, the smelting chamber is closed and evacuated to 5 Pa. At the same time, power is supplied to increase the temperature until the temperature in the furnace reaches 2000°C and the temperature is kept for 2 hours. During the heat preservation process, a graphite rod is used to stir the smelted copper liquid so that the flake graphite powder is fully mixed with beryllium oxide for reaction, reduction and deoxidation, and the generated slag floats;

[0030] (3) Vacuum casting: During the smelting and casting process, the pressure in the smelting chamber and the casting chamber is kept at 5 Pa. When the temperature of the molten copper drops to 1200°C, casting is performed. After the casting is completed, the ingot is completely solidified and then the vacuum is broken and taken out.

[0031] The impurity content of the beryllium copper master alloys of Comparative Example 1 and Examples 1 and 2 was detected, and the results are shown in Table 1;

[0032] The O / H / N element contents of the beryllium copper master alloys of Comparative Example 1 and Examples 1 and 2 were detected, and the results are shown in Table 2.

[0033] Table 1. Impurity content of beryllium copper master alloys of Comparative Example 1 and Examples 1 and 2

[0034]

[0035] Table 2. O / H / N element contents of beryllium copper master alloys of Comparative Example 1 and Examples 1 and 2

[0036]

[0037] It can be seen from the data in Table 1 that the impurity content of the beryllium copper master alloy prepared in the embodiment of the present invention is significantly lower than that in Comparative Example 1. It can be seen from the data in Table 2 that the O / H / N element content of the beryllium copper master alloy prepared in the embodiment of the present invention is also significantly lower than that in Comparative Example 1. It can be seen that the present invention can significantly reduce the oxygen content, other gas content and inclusion content inside the beryllium copper master alloy through the combined process of vacuum melting, vacuum casting and vacuum consumable refining.

[0038] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for efficiently preparing beryllium copper master alloy, characterized in that: The following steps are included: (1) Adding materials: beryllium oxide and flake graphite powder are mixed in a molar ratio of 1.1:1 to obtain beryllium oxide flake graphite powder, an electrolytic copper plate with a purity of 99.99% is placed in a crucible, and the mixed beryllium oxide flake graphite powder is placed in a proportion, wherein the electrolytic copper plate and the beryllium oxide flake graphite powder are mixed in a proportion such that the mass content of the beryllium element accounts for 4% of the total mass of the beryllium element and the copper element; (2) Vacuum smelting: After adding materials, the smelting chamber is closed and evacuated to 5 Pa. At the same time, power is supplied to increase the temperature until the temperature in the furnace reaches 2000°C and the temperature is kept for 2 hours. During the heat preservation process, a graphite rod is used to stir the smelted copper liquid so that the flake graphite powder is fully mixed with beryllium oxide for reaction, reduction and deoxidation, and the generated slag floats; (3) Vacuum casting: During the smelting and casting process, the pressure in the smelting chamber and the casting chamber is kept at 5 Pa. When the temperature of the molten copper drops to 1200°C, casting is performed. After the casting is completed, the ingot is completely solidified and then the vacuum is broken and taken out; (4) Vacuum consumable melting: The obtained ingot is subjected to vacuum consumable melting. The working voltage of the vacuum consumable melting is 30 V, the current is 11000 A, the vacuum degree is 1 Pa, and the feed speed of the working electrode is 15 mm / min, thereby obtaining beryllium copper master alloy.

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