A refiner and its use in brass casting

Abstract

The present application relates to a kind of refiner, comprising: potassium fluoborate, graphite and boron-iron alloy.Preferably, by mass percentage, comprising: potassium fluoborate 70%-90%; Graphite 10%-50%; The balance of boron-iron alloy.The refiner of the present application will form independent nucleation point in molten copper water, and can be used as the attachment point of grain growth before solidification, because the particle is small, a large number of grains can be incubated due to uniform distribution, and after solidification, the polished copper ingot with fine structure can be obtained;The refiner of the present application, or the reaction between refiner and molten copper water, B4C, AlB2 And FeB with modification effect are generated, to refine grain.

Description

Technical Field

[0001] This invention relates to the field of metallurgical casting technology, and in particular to a refining agent and its application in brass casting. Background Technology

[0002] Brass is a special alloy product composed mainly of copper and zinc, supplemented with other microalloys. Due to its good corrosion resistance, wear resistance, ductility, bactericidal properties, high strength, and bright color, brass is widely used in electronic and electrical parts, hardware components, communication connectors, decorative products, and furniture and bathroom products.

[0003] When using brass to produce products, it is necessary to add an appropriate amount of grain refiner. For example, CN103071770A discloses an additive composition and its addition method for producing copper rods by horizontal continuous casting of scrap copper. It specifically discloses that the grain refiner is a rare earth and boron alloy with a mass ratio of 1:1. However, the use of such a grain refiner still leads to coarse grain structure, which in turn causes problems such as cracking and orange peel on the surface of the product, resulting in a serious decrease in yield.

[0004] Therefore, there is an urgent need for a refining agent and its application in brass casting. Summary of the Invention

[0005] The purpose of this invention is to address the shortcomings of the prior art by providing a refining agent and its application in brass casting.

[0006] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0007] A first aspect of the present invention is to provide a refining agent comprising: potassium fluoroborate, graphite, and ferroborone alloy.

[0008] Preferably, by weight percentage, it comprises:

[0009] Potassium fluoroborate 70%-90%;

[0010] Graphite 10%-50%;

[0011] Boron-iron alloy balance.

[0012] Preferably, the graphite is nano-graphite powder.

[0013] Preferably, the ferroborone alloy is ferroborone alloy powder.

[0014] Preferably, the mass ratio of boron to iron in the ferroboron alloy is (3-10):(90-97).

[0015] A second aspect of the present invention is to provide the application of the refining agent as described above in brass casting.

[0016] Preferably, the brass casting step includes:

[0017] S0, Provide an industrial frequency furnace;

[0018] S1. Transfer the refining agent as described above into the industrial frequency furnace;

[0019] S2. Provide casting scrap, the casting scrap including: a first casting scrap and several second casting scraps, transfer the first casting scrap to the industrial frequency furnace, and cover the first casting scrap with the refining agent;

[0020] S3. Provide casting raw materials, the casting raw materials including: the second part of casting recycled material, copper granules, and zinc, and transfer the casting raw materials to the industrial frequency furnace in several batches;

[0021] During the first transfer of the casting raw materials, borax is also transferred into the industrial frequency furnace;

[0022] Before each transfer of the casting raw materials, slag removal is also performed.

[0023] In this process, after the final transfer of the casting raw materials, the materials in the industrial frequency furnace are melted.

[0024] Potassium fluoroborate, graphite, and ferroboron alloys form independent nucleation sites in molten copper. In the early stage of solidification, they can serve as attachment points for grains to grow. Due to their small size and uniform distribution, they can incubate a large number of grains. After solidification, a fine-structured polished copper ingot can be obtained.

[0025] 4KBF4 (potassium fluoroborate) + C (graphite) + 4Al (aluminum in molten copper) → B4C + 4AlF3 + 4KF

[0026] 2KBF4+3Al→AlB2+2AlF3+2KF

[0027] B + Fe → FeB

[0028] Potassium fluoroborate, graphite, and ferroboron alloys can undergo the above-mentioned reactions in molten copper, and the resulting B4C, AlB2, and FeB can play a modifying role to refine the grains.

[0029] S4. Transfer the slag remover into the industrial frequency furnace and stir the material in the industrial frequency furnace.

[0030] S5. The refining agent is transferred to the industrial frequency furnace, and the material in the industrial frequency furnace is subjected to stirring, heating, slag removal and cooling treatment in sequence.

[0031] S6. Transfer the aluminum rare earth to the industrial frequency furnace and stir the material in the industrial frequency furnace.

[0032] S7. Transfer the magnesium block to the industrial frequency furnace. After the material in the industrial frequency furnace is subjected to static treatment and degassing treatment, the material in the industrial frequency furnace is heated to 1080℃-1090℃.

[0033] S8. After spraying the material in the industrial frequency furnace with fire for 13s-17s to stabilize the temperature at 1080℃-1100℃, the material in the industrial frequency furnace is then cast.

[0034] Preferably, the amount of the refining agent added is 0.01%-0.05% of the total mass of the foundry scrap and the foundry raw materials.

[0035] Preferably, the step between step S6 and step S7 further includes:

[0036] A1. Take samples of the materials in the industrial frequency furnace;

[0037] A2. Perform component testing on the sampled sample and determine whether the sample's components are qualified; if not qualified, add the corresponding metal components and return to step A1; if qualified, proceed to step S7.

[0038] Preferably, the step between step S7 and step S8 further includes:

[0039] B1. Take samples of the materials in the industrial frequency furnace;

[0040] B2. Perform a swirl cup quality test on the sampled sample and determine whether the swirl cup quality of the sample is qualified; if it is not qualified, add the refining agent and / or borax and return to step B1; if it is qualified, proceed to step S8.

[0041] The present invention adopts the above technical solution and has the following technical effects compared with the prior art:

[0042] The grain refiner of this invention forms independent nucleation sites in molten copper. In the early stage of solidification, it can serve as attachment points for grains with long growth. Due to the small size and uniform distribution of the particles, a large number of grains can be incubated. After solidification, a polished copper ingot with fine structure can be obtained. The grain refiner of this invention can also react with each other, or with the grain refiner and molten copper, to generate B4C, AlB2 and FeB, which have a refining effect, in order to refine the grains. Attached Figure Description

[0043] Figure 1 The image shows the metallographic analysis results of Application Example 1 at 100×.

[0044] Figure 2The image shows the metallographic analysis results of Example 2 at 100×.

[0045] Figure 3 The image shows the metallographic analysis results of Example 3 at 100×.

[0046] Figure 4 The image shows the metallographic analysis results of Example 4 at 200×. Detailed Implementation

[0047] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0048] It should be noted that, unless otherwise specified, the embodiments and features described in the present invention can be combined with each other.

[0049] The present invention will be further described below with reference to the accompanying drawings and specific embodiments, but this is not intended to limit the scope of the invention.

[0050] Example 1

[0051] This embodiment provides a refining agent, comprising, by mass percentage:

[0052] Potassium fluoroborate 75%;

[0053] 15% nano-graphite powder;

[0054] 10% ferroborone alloy powder;

[0055] In the ferroboron alloy, the mass ratio of boron to iron is 5:95.

[0056] Example 2

[0057] This embodiment provides a refining agent, comprising, by mass percentage:

[0058] Potassium fluoroborate 80%;

[0059] 10% nano-graphite powder;

[0060] 10% ferroborone alloy powder;

[0061] In the aforementioned ferroboron alloy, the mass ratio of boron to iron is 10:90.

[0062] Example 3

[0063] This embodiment provides a refining agent, comprising, by mass percentage:

[0064] Potassium fluoroborate 85%;

[0065] 10% nano-graphite powder;

[0066] 5% boron-iron alloy powder;

[0067] In the ferroboron alloy, the mass ratio of boron to iron is 5:95.

[0068] Comparative Example

[0069] This comparative example provides another refining agent, including calcium carbonate and ferroboron powder, etc.

[0070] Application Examples

[0071] This application embodiment provides the application of a refining agent in brass casting, wherein the brass casting steps include:

[0072] S0, Provide an industrial frequency furnace;

[0073] S1. Transfer the refining agent (800g) as described in Example 1, Example 2, Example 3, or Comparative Example into the industrial frequency furnace;

[0074] S2. Provide casting scrap, the casting scrap including: a first casting scrap and several second casting scraps, transfer the first casting scrap to the industrial frequency furnace, and cover the first casting scrap with the refining agent;

[0075] S3. Provide casting raw materials, which include: the second batch of casting recycled material (totaling 1500 kg with the first batch of casting recycled material), copper granules (720 kg), and 0# zinc (480 kg), and transfer the casting raw materials to the industrial frequency furnace in several batches;

[0076] During the first transfer of the casting raw materials, borax (500g) is also transferred into the industrial frequency furnace;

[0077] Before each transfer of the casting raw materials, slag removal is also performed.

[0078] In this process, after the final transfer of the casting raw materials, the materials in the industrial frequency furnace are melted.

[0079] S4. Transfer the slag remover (2kg) into the industrial frequency furnace and stir the material in the industrial frequency furnace.

[0080] S5. Transfer the refining agent (2kg) into the industrial frequency furnace, and sequentially perform stirring, heating, slag removal and cooling on the material in the industrial frequency furnace.

[0081] S6. Transfer the aluminum rare earth (60g) into the industrial frequency furnace and stir the material in the industrial frequency furnace.

[0082] A1. Take a first sample of the material in the industrial frequency furnace;

[0083] A2. Perform composition testing on the first sample and determine whether the composition of the sample is qualified; if it is not qualified, add the corresponding metal component and return to step A1; if it is qualified, proceed to step S7.

[0084] Specifically, the criteria for determining whether the composition of the sample is qualified are as follows:

[0085] Cu Zn Sn Pb Fe Ni Al P Si S 59.5-61 margin ≤0.18 1.3-1.5 ≤0.2 ≤0.2 0.50-0.65 0.005-0.01 ≤0.01 ≤0.01 Cd Bi Cr Sb Mg As Co B Mn ≤0.01 ≤0.02 ≤0.02 ≤0.02 ≤0.01 ≤0.02 ≤0.01 ≤0.001 ≤0.1

[0086] S7. Transfer the magnesium block (120g) to the industrial frequency furnace. After the material in the industrial frequency furnace is subjected to static treatment and degassing treatment, the material in the industrial frequency furnace is heated to 1080℃-1090℃.

[0087] B1. Take a second sample of the material in the industrial frequency furnace;

[0088] B2. Perform a swirl cup quality test on the second sample and determine whether the swirl cup quality of the sample is qualified; if it is not qualified, add the refining agent and / or borax and return to step B1; if it is qualified, proceed to step S8.

[0089] S8. After spraying the material in the industrial frequency furnace with fire for 13s-17s to stabilize the temperature at 1080℃-1100℃, the material in the industrial frequency furnace is then cast.

[0090] C1. Polish the copper ingots obtained from the casting process and observe the shrinkage, porosity, and hard spots to determine the quality of the copper ingots.

[0091] Detection Examples

[0092] The application examples corresponding to Examples 1, 2, 3, or comparative examples are sequentially referred to as Application Example 1, Application Example 2, Application Example 3, and Application Example 4.

[0093] Metallographic analysis of polished copper ingots was performed using the macrostructure inspection method for copper and copper alloy castings and processed products (YS / T 448-2002).

[0094] Grain size analysis was performed on polished copper ingots according to YS / T 347-2020, which specifies the method for determining the average grain size of copper and copper alloys.

[0095] The component test results of Application Example 1 are shown in the table below:

[0096] Cu Zn Sn Pb Fe Ni Al P Si S 59.785 margin 0.0327 1.3273 0.052 0.0419 0.5294 0.0071 0.006 0.001 Cd Bi Cr Sb Mg As Co B Mn 0.0055 0.0038 0.0117 0.0176 0.0089 0.0105 0.0014 0.0007 0.0376

[0097] The results of the cup-spinning quality test in Application Example 1 are as follows: the cup-spinning quality is good, the cup-spinning is very fine, and the ends and sides show good smoothness.

[0098] The results observed after polishing in Example 1 were: the polished surface had a high degree of smoothness and was free of defects such as hard spots and pores;

[0099] The metallographic analysis results of Application Example 1 are as follows Figure 1 As shown, the structure is mainly composed of α and β phases, with grains mainly in the form of islands, without dendrites, and the distribution is uniform. No mixed crystals are present, and lead particles are uniformly distributed at grain boundaries and within grains.

[0100] The grain size analysis results of Application Example 1 are: the average is less than 20 μm.

[0101] The component test results of Application Example 2 are shown in the table below:

[0102] Cu Zn Sn Pb Fe Ni Al P Si S 60.1008 margin 0.0757 1.4571 0.0188 0.0467 0.6412 0.0085 0.0087 0.001 Cd Bi Cr Sb Mg As Co B Mn 0.0066 0.0043 0.0097 0.0187 0.0001 0.011 0.0014 0.0001 0.053

[0103] The results of the cup-spinning quality test in Application Example 2 are as follows: the cup-spinning quality is good, the cup-spinning is very fine, and the ends and sides show good smoothness.

[0104] The results observed after polishing in Example 2 were as follows: the polished surface was fine and free of defects such as hard spots and pores.

[0105] The metallographic analysis results of Application Example 2 are as follows Figure 2 As shown, the structure is mainly composed of α phase and β phase, with grains mainly in the form of islands, a small number of short rods, no dendrites, and uniform distribution. No mixed crystals are observed, and lead particles are uniformly distributed at grain boundaries and within grains.

[0106] The grain size analysis results of Application Example 2 are: the average is less than 20 μm.

[0107] The component test results of Application Example 3 are shown in the table below:

[0108] Cu Zn Sn Pb Fe Ni Al P Si S 60.156 margin 0.0329 1.421 0.0532 0.0922 0.57 0.0065 0.0063 0.0013 Cd Bi Cr Sb Mg As Co B Mn 0.0047 0.0066 0.0030 0.0155 0.0022 0.0113 0.0018 0.0003 0.0562

[0109] The results of the cup-spinning quality test in Application Example 3 are as follows: the cup-spinning quality is good, the cup-spinning is very fine, and the ends and sides show good smoothness.

[0110] The results observed after polishing in Example 3 were as follows: the polished surface had high smoothness and fineness, and was free of defects such as hard spots and pores.

[0111] The metallographic analysis results of Application Example 3 are as follows: Figure 3As shown, the microstructure is mainly composed of α and β phases, with grains mainly in the form of islands and a small number of short rods. The grains are evenly distributed and no mixed crystals are observed. Lead particles are evenly distributed at grain boundaries and within the grains.

[0112] The grain size analysis results of Application Example 3 are: the average is less than 25 μm.

[0113] The component test results of Application Example 4 are shown in the table below:

[0114]

[0115]

[0116] The results of the cup-spinning quality test in Application Example 4 were as follows: the cup-spinning quality was poor, the graininess at the ends and sides was very obvious, and there was a very obvious orange peel texture.

[0117] The results observed after polishing in Example 4 were: obvious hard spots were present on the polished surface;

[0118] The metallographic analysis results of Application Example 4 are as follows: Figure 4 As shown, the microstructure is mainly composed of α and β phases, with short rod-shaped grains that tend to dendrite and a small number of isolated islands, resulting in mixed crystal problems. Lead particles are evenly distributed at grain boundaries and within grains.

[0119] The grain size analysis results of Application Example 4 are: the average is greater than 50 μm.

[0120] In summary, the grain refiner of the present invention forms independent nucleation sites in molten copper. In the early stage of solidification, it can serve as an attachment point for grains with long growth. Due to the small size and uniform distribution of the particles, a large number of grains can be incubated. After solidification, a polished copper ingot with fine structure can be obtained. The grain refiner of the present invention can also react with each other, or with the grain refiner and molten copper, to generate B4C, AlB2 and FeB, which have a refining effect, in order to refine the grains.

[0121] The above description is merely a preferred embodiment of the present invention and does not limit the implementation and protection scope of the present invention. Those skilled in the art should realize that any equivalent substitutions and obvious changes made based on the description and illustrations of the present invention should be included within the protection scope of the present invention.

Claims

1. A refining agent, characterized by, By mass percentage, comprising: Potassium fluoborate 75%-85%; Nano graphite powder 10%-15%; Boron-iron alloy powder 5%-10%; The mass ratio of boron to iron in the boron-iron alloy powder is (3-10):(90-97).

2. The application of the refining agent in claim 1 in brass casting.

3. Use according to claim 2, characterized in that, The steps of the brass casting include: S0, providing a power frequency furnace; S1, transferring the refining agent in claim 1 into the power frequency furnace; S2, providing casting return materials, the casting return materials including: a first portion of the casting return materials, and a plurality of second portions of the casting return materials, transferring the first portion of the casting return materials into the power frequency furnace, and covering the first portion of the casting return materials on the refining agent; S3, providing casting raw materials, the casting raw materials including: the second portion of the casting return materials, red copper grains, and zinc, transferring the casting raw materials into the power frequency furnace in batches; wherein, when transferring the casting raw materials for the first time, borax is also transferred into the power frequency furnace; wherein, before transferring the casting raw materials each time, slag handling is also performed; wherein, after transferring the casting raw materials for the last time, the materials in the power frequency furnace are melted; S4, transferring a deslagging agent into the power frequency furnace, and stirring the materials in the power frequency furnace; S5, transferring a refining agent into the power frequency furnace, and sequentially performing stirring, temperature rising, slag handling, and temperature lowering on the materials in the power frequency furnace; S6, transferring aluminum-rare earth into the power frequency furnace, and stirring the materials in the power frequency furnace; S7, transferring magnesium blocks into the power frequency furnace, after performing standing and degassing on the materials in the power frequency furnace, the materials in the power frequency furnace are heated to 1080-1090℃; S8, after spraying fire on the materials in the power frequency furnace for 13-17s to stabilize the temperature at 1080-1100℃, the materials in the power frequency furnace are cast.

4. Use according to claim 3, characterized in that, The adding amount of the refining agent is 0.01%-0.05% of the total mass of the casting return materials and the casting raw materials.

5. Use according to claim 3, characterized in that, Between step S6 and step S7, further comprising: A1, sampling the materials in the power frequency furnace; A2, testing the composition of the sampled sample, and determining whether the composition of the sample is qualified; if not, the corresponding metal component is added, and then returning to step A1; if qualified, step S7 is executed.

6. Use according to claim 3, characterized in that, Between step S7 and step S8, further comprising: B1, sampling the materials in the power frequency furnace; B2, testing the cup quality of the sampled sample, and determining whether the cup quality of the sample is qualified; if not, the refining agent or / and borax is added, and then returning to step B1; if qualified, step S8 is executed.

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