Preparation and use method of gradient slow-release deoxidation alloying agent

Abstract

The invention discloses a preparation and use method of a gradient slow-release deoxidation alloying agent, and the preparation method specifically comprises the following steps: (1) crushing and uniformly mixing the deoxidation alloying agent, loading the deoxidation alloying agent into a steel pipe, and pressing the steel pipe to a compact state; (2) cutting the steel pipe into deoxidation alloying agent blocks with a certain length; and (3) carrying out gradient matching on the deoxidation alloying agent blocks with different pipe wall diameters and different pipe wall thicknesses to obtain the gradient slow-release deoxidation alloying agent. When tapping is carried out after a converter, the gradient slow-release deoxidation alloying agent is put into a steel ladle for deoxidation alloying, the deoxidation alloying effect can be effectively improved, the alloy yield is increased, the smelting production cost is reduced, the alloy uniform melting time is shortened, the production efficiency is improved, and the steel product quality is improved; therefore, the problems of slow alloy melting, low alloy yield and the like in the converter smelting process are solved, and the increasingly strict requirements of steel quality are met.

Description

Technical Field

[0001] The present invention relates to the technical field of iron and steel metallurgy, and more specifically to a preparation and use method of a gradient slow-release deoxidizing alloying agent. Background Art

[0002] Deoxidizing alloying, as a key process link in steel smelting, mainly aims to react deoxidizing alloying agents (such as manganese, silicon, aluminum, etc.) with oxygen in the molten steel to generate oxide inclusions (such as Al2O3, SiO2) that are insoluble in the molten steel, and promote these inclusions to float to the slag, significantly reducing the oxygen content and non-metallic inclusions in the material. During the deoxidation process, alloying elements (such as chromium, nickel, titanium, etc.) are added synchronously to compensate for melting losses and adjust the chemical composition in the steel to meet the performance requirements of specific steel grades and improve the mechanical properties of the steel.

[0003] As the core material for achieving the dual goals of deoxidation and alloying in steel smelting, the technical level of deoxidizing alloying agents directly affects the purity of molten steel, alloy recovery rate, and steel properties. Currently, in the deoxidizing alloying process of converter steelmaking, bulk alloys are mainly added through a feeding bin. To prevent dust pollution and facilitate the addition of alloys, alloys are required to have a relatively large particle size. However, there are also certain problems in the deoxidizing alloying process. For example, the reaction rate of some deoxidizing alloying processes (such as diffusion deoxidation) is slow, and the smelting time needs to be extended to ensure the deoxidation effect, resulting in an extended smelting cycle and a decrease in production efficiency; the alloy recovery rate of high-efficiency deoxidizers (such as aluminum) is low and the price is expensive, resulting in a significant increase in smelting costs; the addition method of alloying elements in traditional processes is prone to cause fluctuations in the composition of molten steel and uneven distribution of alloying elements, affecting the consistency of steel properties. For example, if deoxidizing agents such as ferrosilicon are not fully dissolved or mixed, local supersaturation or deficiency may occur.

[0004] Therefore, how to develop new deoxidizing alloying agents on the basis of ensuring the stable operation of the existing production process is an urgent problem to be solved by those skilled in the art. Summary of the Invention

[0005] In view of this, the purpose of the present invention is to provide a preparation and use method of a gradient slow-release deoxidizing alloying agent to solve the deficiencies in the prior art.

[0006] To achieve the above purpose, the present invention adopts the following technical solutions:

[0007] A preparation method of a gradient slow-release deoxidizing alloying agent specifically includes the following steps:

[0008] (1) Crush and mix the deoxidizing alloying agent, load it into a steel pipe, and press it to a dense state;

[0009] (2) Cut the steel pipe into deoxidizing alloying agent blocks of a certain length;

[0010] (3) Gradiently match the deoxidizing alloying agent blocks with different pipe wall diameters and different pipe wall thicknesses to obtain a gradient slow-release deoxidizing alloying agent.

[0011] Further, in the above step (1), the deoxidizing alloying agent is at least one of ferromanganese alloy powder, ferrosilicon alloy powder, chromium niobium vanadium alloy powder, and aluminum powder.

[0012] The beneficial effect of adopting the above is that the selected powdered deoxidizing alloying agent in the present invention has a larger specific surface area, can react with oxygen in the molten steel quickly, shorten the deoxidation time, and has high deoxidation efficiency.

[0013] Further, in the above step (1), the material of the steel pipe is low-carbon steel, the pipe wall diameter is 5 - 30 mm, the pipe wall thickness is 0.5 - 2 mm, and the pipe is filled with the deoxidizing alloying agent.

[0014] Further, in the above step (2), the length of the deoxidizing alloying agent block is 5 - 30 mm, and both ends are sealed with heat-sealing glue. Further, the heat-sealing glue is polyimide (PI) heat-sealing glue.

[0015] Further, in the above step (3), the operation of gradient matching is specifically: Gradiently match the deoxidizing alloying agent blocks with different pipe wall diameters in three gradients of large, medium, and small, and gradiently match the deoxidizing alloying agent blocks with different pipe wall thicknesses in three gradients of thick, medium, and thin.

[0016] The present invention also claims a gradient slow-release deoxidizing alloying agent prepared by the above preparation method.

[0017] A method for using a gradient slow-release deoxidizing alloying agent prepared by the above preparation method. When tapping steel behind the converter furnace, put the gradient slow-release deoxidizing alloying agent into the ladle for deoxidation alloying.

[0018] It can be seen from the above technical solutions that compared with the prior art, the beneficial effects of the present invention are as follows:

[0019] 1. The gradient slow-release deoxidizing alloying agent of the present invention has a faster melting rate, reduces the time of the deoxidation alloying process, can further optimize the production process, shortens the entire smelting cycle, and improves the production efficiency and production capacity of the steel mill.

[0020] 2. The gradient slow-release deoxidizing alloying agent of the present invention is simple and practical, is of great benefit to the subsequent optimization of the converter smelting process, solves the problems of long alloy deoxidation time, low alloy recovery rate, and slow melting rate in the traditional deoxidation alloying process, and at the same time reduces the production cost and improves the production efficiency.

[0021] 3. During tapping in the back of the converter, putting the gradient slow-release deoxidizing alloying agent of the present invention into the ladle for deoxidizing alloying can effectively improve the deoxidizing alloying effect, increase the alloy recovery rate, reduce the smelting production cost, shorten the alloy uniform melting time, improve the production efficiency, and improve the quality of steel products, thus solving the problems such as slow alloy melting and low alloy recovery rate in the converter smelting process to meet the increasingly strict requirements for steel quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a schematic flow chart of the preparation method of the gradient slow-release deoxidizing alloying agent in Examples 1-3;

[0023] Among them, 1 - deoxidizing alloying agent (ferromanganese alloy powder, ferrosilicon alloy powder, aluminum powder), 2 - steel pipe, 3 - deoxidizing alloying agent block (ferromanganese alloy block, ferrosilicon alloy block, aluminum alloy block), 4 - polyimide heat-sealing adhesive. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0024] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0025] Example 1

[0026] The preparation method of the gradient slow-release deoxidizing alloying agent is as Figure 1 shown, and specifically includes the following steps:

[0027] (1) First, crush and mix manganese iron blocks to obtain ferromanganese alloy powder 1, crush and mix silicon iron blocks to obtain ferrosilicon alloy powder 1, and then put ferromanganese alloy powder 1 and ferrosilicon alloy powder 1 into steel pipe 2 respectively and press them to a dense state;

[0028] (2) Cut the steel pipe 2 filled with ferromanganese alloy powder 1 into ferromanganese alloy blocks 3 of a certain length, cut the steel pipe 2 filled with ferrosilicon alloy powder 1 into ferrosilicon alloy blocks 3 of a certain length, and seal both ends with polyimide heat-sealing adhesive 4;

[0029] (3) Gradiently match the ferromanganese alloy block 3 with a diameter of 10 mm, a length of 15 mm, and a wall thickness of 0.7 mm and the ferrosilicon alloy block 3 with a diameter of 10 mm, a length of 15 mm, and a wall thickness of 1 mm to obtain the gradient slow-release deoxidizing alloying agent.

[0030] The usage method of the above-mentioned gradient slow-release deoxidizing alloying agent specifically includes the following steps:

[0031] When smelting plain carbon steel and performing deoxidation alloying on the ladle after the furnace, the above-mentioned gradient slow-release deoxidation alloying agent is used; when one-third of the molten steel is tapped (observed according to the tapping angle), ferromanganese alloy blocks 3 are preferentially added, and finally ferrosilicon alloy blocks 3 are added. The two types of deoxidation alloying agents with different formulations are put into the ladle for deoxidation alloying operation.

[0032] Example 2

[0033] The preparation method of the gradient slow-release deoxidation alloying agent is as Figure 1 shown, and specifically includes the following steps:

[0034] (1) First, crush and mix manganese iron blocks to obtain ferromanganese alloy powder 1, crush and mix silicon iron blocks to obtain ferrosilicon alloy powder 1, crush and mix aluminum blocks to obtain aluminum powder 1. Then, load ferromanganese alloy powder 1, ferrosilicon alloy powder 1, and aluminum powder 1 into steel pipes 2 respectively, and press them into a dense state;

[0035] (2) Cut the steel pipe 2 filled with ferromanganese alloy powder 1 into ferromanganese alloy blocks 3 of a certain length, cut the steel pipe 2 filled with ferrosilicon alloy powder 1 into ferrosilicon alloy blocks 3 of a certain length, cut the steel pipe 2 filled with aluminum powder 1 into aluminum alloy blocks 3 of a certain length, and seal both ends with polyimide heat-sealing glue 4;

[0036] (3) Gradiently match ferromanganese alloy blocks 3 with a diameter of 20 mm, a length of 30 mm, and a wall thickness of 0.5 mm, ferrosilicon alloy blocks 3 with a diameter of 20 mm, a length of 30 mm, and a wall thickness of 1 mm, and aluminum alloy blocks 3 with a diameter of 20 mm, a length of 30 mm, and a wall thickness of 1.5 mm, and the gradient slow-release deoxidation alloying agent is obtained.

[0037] The usage method of the above-mentioned gradient slow-release deoxidation alloying agent specifically includes the following steps:

[0038] When smelting high-quality steel and performing deoxidation alloying on the ladle after the furnace, the above-mentioned gradient slow-release deoxidation alloying agent is used; when one-third of the molten steel is tapped (observed according to the tapping angle), ferromanganese alloy blocks 3 are preferentially added, followed by ferrosilicon alloy blocks 3, and finally aluminum alloy blocks 3 are added. The three types of deoxidation alloying agents with different formulations are put into the ladle for deoxidation alloying operation.

[0039] Example 3

[0040] The preparation method of the gradient slow-release deoxidation alloying agent is as Figure 1 shown, and specifically includes the following steps:

[0041] (1) First, crush and mix manganese iron blocks to obtain ferromanganese alloy powder 1, crush and mix aluminum blocks to obtain aluminum powder 1. Then, load ferromanganese alloy powder 1 and aluminum powder 1 into steel pipes 2 respectively, and press them into a dense state;

[0042] (2) Cut the steel pipe 2 filled with ferromanganese alloy powder 1 into ferromanganese alloy blocks 3 of a certain length, and cut the steel pipe 2 filled with aluminum powder 1 into aluminum alloy blocks 3 of a certain length, and seal both ends with polyimide heat-sealing glue 4;

[0043] (3) Gradiently match the ferromanganese alloy block 3 with a diameter of 20 mm, a length of 30 mm, and a wall thickness of 0.5 mm and the aluminum alloy block 3 with a diameter of 15 mm, a length of 20 mm, and a wall thickness of 1.5 mm, and the gradient slow-release deoxidizing alloying agent is obtained.

[0044] The usage method of the above-mentioned gradient slow-release deoxidizing alloying agent specifically includes the following steps:

[0045] When smelting high-quality steel and the tapping temperature is 1600 °C, and deoxidizing alloying is carried out in the ladle after tapping, use the above-mentioned gradient slow-release deoxidizing alloying agent; when one-third of the steel is tapped (observed according to the tapping angle), first add the ferromanganese alloy block 3, and finally add the aluminum alloy block 3, put the two different matching deoxidizing alloying agents into the ladle, and carry out the deoxidizing alloying operation.

[0046] Performance test

[0047] Carry out deoxidizing alloying tests on traditional deoxidizing alloying agents and gradient slow-release deoxidizing alloying agents using a 150 kg intermediate frequency induction furnace.

[0048] 1 Test preparation

[0049] 1.1 Molten steel

[0050] Smelt 100 kg of molten steel in an intermediate frequency induction furnace, blow the steel to 1600 °C for tapping, and carry out deoxidizing alloying during the tapping process. Among them, the steel grade Q235 is equipped with alloying elements according to 0.25% Si and 0.51% Mn of the target steel grade.

[0051] 1.2 Deoxidizing alloying agent

[0052] Prepare ferromanganese blocks and ferrosilicon blocks, and their main components are shown in Table 1.

[0053] Table 1 Main components of ferromanganese blocks and ferrosilicon blocks (average mass fraction)

[0054] Element C Si Mn P S Others Ferromanganese (%) 0.6 2 81.9 0.12 0.01 Balance Ferrosilicon (%) 1.1 73.6 0.2 0.05 0.005 Balance

[0055] 1.2.1 Traditional deoxidizing alloying agent

[0056] Crush and mix the ferromanganese blocks to obtain ferromanganese alloy powder, and crush and mix the ferrosilicon blocks to obtain ferrosilicon alloy powder, with a particle size of 5 - 15 mm, to obtain the traditional deoxidizing alloying agent.

[0057] 1.2.2 Gradient slow-release deoxidizing alloying agent

[0058] First, crush and mix the manganese iron blocks to obtain manganese iron alloy powder, and crush and mix the silicon iron blocks to obtain silicon iron alloy powder, both with a particle size of 5 - 15 mm. Then, according to the method of Example 1, make the manganese iron alloy powder and silicon iron alloy powder into a manganese iron alloy block with a diameter of 10 mm, a length of 15 mm, and a wall thickness of 0.7 mm, and a silicon iron alloy block with a diameter of 10 mm, a length of 15 mm, and a wall thickness of 1 mm (the particle size of the internal alloy powder is 1 mm), and match them in gradients to obtain a gradient slow-release deoxidizing alloying agent.

[0059] 2 Test steps

[0060] When smelting plain carbon steel and performing deoxidizing alloying in the ladle behind the furnace, use a traditional deoxidizing alloying agent (or gradient slow-release deoxidizing alloying agent). When one-third of the steel is tapped (observed according to the tapping angle), preferably add the manganese iron alloy powder (or manganese iron alloy block) first, and finally add the silicon iron alloy powder (or silicon iron alloy block). Put the two different matched deoxidizing alloying agents into the ladle for deoxidizing alloying operations.

[0061] The addition amount of the deoxidizing alloying agent is shown in Table 2.

[0062] Table 2 Addition amount of the deoxidizing alloying agent

[0063]

[0064]

[0065] After all the deoxidizing alloying agent is added, wait for the tapping to be completed, use an iron rod to stir instead of bottom gas stirring, and take samples for testing after the alloy melts.

[0066] The alloy recovery rate of the deoxidizing alloying agent is shown in Table 3.

[0067] Table 3 Alloy recovery rate of the deoxidizing alloying agent

[0068]

[0069] As can be seen from Table 3, compared with the traditional deoxidizing alloying agent, the gradient slow-release deoxidizing alloying agent in Example 1 significantly improves the alloy recovery rate.

[0070] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to these embodiments shown herein, but rather to the broadest scope consistent with the principles and novel features disclosed herein.

Claims

1. A preparation method of a gradient slow-release deoxidizing alloying agent, characterized in that, Specifically, it includes the following steps: (1) Crush and mix the deoxidizing alloying agent, load it into a steel pipe, and press it to a dense state; (2) Cut the steel pipe into deoxidizing alloying agent blocks of a certain length; (3) Gradiently match the deoxidizing alloying agent blocks with different pipe wall diameters and different pipe wall thicknesses, and the gradient slow-release deoxidizing alloying agent is obtained.

2. The preparation method of a gradient slow-release deoxidizing alloying agent according to claim 1, characterized in that, In step (1), the deoxidizing alloying agent is at least one of ferromanganese alloy powder, ferrosilicon alloy powder, chromium niobium vanadium alloy powder, and aluminum powder.

3. The preparation method of a gradient slow-release deoxidizing alloying agent according to claim 1, characterized in that, In step (1), the material of the steel pipe is low-carbon steel, the pipe wall diameter is 5 - 30 mm, and the pipe wall thickness is 0.5 - 2 mm.

4. The preparation method of a gradient slow-release deoxidizing alloying agent according to claim 1, characterized in that, In step (2), the length of the deoxidizing alloying agent block is 5 - 30 mm, and both ends are sealed with heat-sealing glue.

5. The preparation method of a gradient slow-release deoxidizing alloying agent according to claim 4, characterized in that, The heat-sealing glue is polyimide heat-sealing glue.

6. The preparation method of a gradient slow-release deoxidizing alloying agent according to claim 1, characterized in that, In step (3), the specific operation of the gradient matching is as follows: Gradiently match the deoxidizing alloying agent blocks with different pipe wall diameters in three gradients of large, medium, and small, and gradiently match the deoxidizing alloying agent blocks with different pipe wall thicknesses in three gradients of thick, medium, and thin.

7. A gradient slow-release deoxidizing alloying agent prepared by the preparation method according to any one of claims 1 - 6.

8. A method for using a gradient slow-release deoxidizing alloying agent prepared by the preparation method according to any one of claims 1-6, characterized in that, When tapping steel behind the converter furnace, put the gradient slow-release deoxidizing alloying agent into the ladle for deoxidation alloying.

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