Aluminum-magnesium ladle lining gunning material, preparation method and application thereof

Abstract

This application discloses an aluminum-magnesium alloy steel ladle wall spraying material, its preparation method, and its application. The raw materials of the spraying material include the following components by weight percentage: 50%–55% corundum, 20%–25% spinel, 10%–15% α-alumina micro powder, 2%–4% calcium aluminate cement, 2%–4% p-alumina, 1%–2% metallic aluminum powder, 0.1%–0.2% water-reducing agent, and 2%–4% zirconium oxychloride. Through the combination of its components, the above-mentioned aluminum-magnesium alloy steel ladle wall spraying material exhibits good high-temperature mechanical strength, resistance to chemical corrosion, long service life, and low production cost during use.

Description

Technical Field

[0001] This application relates to the field of refractory materials technology, and in particular to an aluminum-magnesium steel ladle wall spraying material, its preparation method and application. Background Technology

[0002] The steel ladle is an important thermal equipment in the steelmaking process, mainly used for steel transportation and pouring. Typically, MgO-C and MgO-CaO-C bricks are used as the refractory lining material for the slag line area; while the refractory materials for the ladle walls and bottom areas of the refining ladle usually use fused alumina, tabular alumina, and aluminum-rich spinel as the main raw materials.

[0003] During the refining process of molten steel, the ladle temperature can reach over 1750℃, causing severe erosion and accelerated damage to the ladle wall material. The refining process involves stirring the molten steel, which carries slag that erodes the ladle wall material, easily causing it to detach. In some refining processes, the ladle is subjected to vacuum treatment, and the vacuum environment can alter the properties of the ladle wall refractory material. Furthermore, the large temperature fluctuations during refining, due to rapid heating and cooling, can cause the ladle wall refractory material to spall due to thermal stress. These harsh operating environments place high demands on the refractory materials used for ladle walls, requiring excellent erosion resistance, high-temperature erosion resistance, high-temperature vacuum stability, and high-temperature spalling resistance. Summary of the Invention

[0004] This invention provides an aluminum-magnesium steel ladle wall patching material, its preparation method, and its application, in order to solve the technical problem of high performance requirements for ladle wall materials in the existing steel refining process.

[0005] To achieve the above objectives, the technical solution provided by the present invention is as follows:

[0006] In a first aspect, the present invention provides an aluminum-magnesium steel ladle wall spraying material, the raw materials of which include the following components by weight percentage: 50% to 55% corundum, 20% to 25% spinel, 10% to 15% α-alumina micro powder, 2% to 4% calcium aluminate cement, 2% to 4% p-alumina, 1% to 2% metallic aluminum powder, 0.1% to 0.2% water-reducing agent, and 2% to 4% zirconium oxychloride.

[0007] Furthermore, the content of Al2O3 in the p-alumina is greater than or equal to 98 wt.%; the particle size of the p-alumina is less than or equal to 90 μm.

[0008] Furthermore, the ZrOCl2·8H2O content in the zirconium oxychloride is greater than or equal to 98 wt.%.

[0009] Furthermore, the corundum is selected from one or more of dense corundum, brown corundum, white corundum, and tabular corundum, and the content of Al2O3 in the corundum is greater than or equal to 99 wt.%.

[0010] Furthermore, the particle size distribution of the corundum is as follows: the content of particles smaller than 5 mm and greater than or equal to 3 mm is 25 wt.% to 45 wt.%, the content of particles smaller than 3 mm and greater than or equal to 1 mm is 10 wt.% to 15 wt.%, the content of particles smaller than 1 mm and greater than or equal to 0.088 mm is 10 wt.% to 15 wt.%, the content of particles smaller than 0.088 mm and greater than or equal to 0.045 mm is 25 wt.% to 30 wt.%, and the content of particles smaller than 0.045 mm is 10 wt.% to 15 wt.%.

[0011] Furthermore, the spinel contains an Al2O3 content greater than or equal to 78 wt.% and an MgO content greater than or equal to 21 wt.%; the spinel has a particle size distribution of 40 wt.% to 60 wt.% for particles of 1 to 0.088 mm and 40 wt.% to 60 wt.% for particles smaller than 0.088 mm.

[0012] Furthermore, the Al2O3 content in the α-alumina micro powder is greater than or equal to 98 wt.%; the particle size of the α-alumina micro powder is less than or equal to 2 μm.

[0013] Furthermore, the aluminum powder contains an Al content greater than or equal to 97 wt.% and has a particle size less than or equal to 0.075 mm.

[0014] Furthermore, the water-reducing agent is selected from one or more of sodium tripolyphosphate, sodium hexametaphosphate, sodium polyacrylate, and melamine.

[0015] In a second aspect, the present invention provides a method for preparing the above-mentioned aluminum-magnesium steel ladle wall spraying material, comprising weighing corundum, spinel, α-alumina micro powder, calcium aluminate cement, ρ-alumina and metallic aluminum powder according to the proportions, mixing them, and then weighing water-reducing agent and zirconium oxychloride according to the proportions and adding and stirring to obtain the aluminum-magnesium steel ladle wall spraying material.

[0016] A third aspect of the present invention provides the application of the above-mentioned aluminum-magnesium steel ladle wall repair material in the repair of steel ladle walls.

[0017] Furthermore, the application includes the following steps: adding water to the aluminum-magnesium steel ladle wall patching material, mixing, and pumping wet spraying onto the inner lining of the steel ladle wall.

[0018] The aluminum-magnesium steel ladle wall spraying material provided by this invention reduces the amount of calcium aluminate cement added to the spraying material by adding p-alumina, thereby improving the intermediate-temperature strength of the spraying material. Simultaneously, it reduces the amount of liquid phase generated at high temperatures, improving the high-temperature strength of the spraying material. Furthermore, the addition of inexpensive zirconium oxychloride to the spraying material allows it to dissolve in water during use, generating zirconium oxide in the pores of the spraying material upon temperature rise, thus enhancing corrosion resistance and extending the service life of the spraying material. Through the proper combination of its components, the above-mentioned aluminum-magnesium steel ladle wall spraying material exhibits good high-temperature mechanical strength, resistance to chemical corrosion, long service life, and low production cost during use.

[0019] The aforementioned aluminum-magnesium alloy ladle wall patching compound allows for repeated patching and maintenance during each working interval of the ladle, providing comprehensive and routine care for the ladle wall refractory material and extending its service life. It can also repair locally damaged ladle wall linings or increase the thickness of the lining in key areas, eliminating potential hazards and accidents related to the lining. Detailed Implementation

[0020] To enable those skilled in the art to better understand the technical solutions in this application, the technical solutions in the embodiments of this application will be clearly and completely described below. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0021] A first aspect of this application provides an aluminum-magnesium steel ladle wall spray patch material, the raw materials of which include the following components by weight percentage: 50% to 55% corundum, 20% to 25% spinel, 10% to 15% α-alumina micro powder, 2% to 4% calcium aluminate cement, 2% to 4% ρ-alumina, 1% to 2% metallic aluminum powder, 0.1% to 0.2% water-reducing agent, and 2% to 4% zirconium oxychloride.

[0022] Existing ladle wall spraying materials generally use a calcium aluminate cement system. The aluminum-magnesium alloy ladle wall spraying material of this application, by adding p-alumina, reduces the amount of calcium aluminate cement required, thus improving the intermediate-temperature strength of the spraying material. Simultaneously, it reduces the amount of liquid phase generated at high temperatures, improving the high-temperature strength. Furthermore, the addition of inexpensive zirconium oxychloride, which dissolves in water during use and forms zirconium oxide in the pores of the spraying material upon temperature rise, enhances corrosion resistance and extends its service life. Through the proper combination of its components, the aforementioned aluminum-magnesium alloy ladle wall spraying material exhibits good high-temperature mechanical strength, resistance to chemical corrosion, long service life, and low production cost during use.

[0023] In some embodiments, the corundum is selected from one or more of dense corundum, brown corundum, white corundum, and tabular corundum, and the Al2O3 content in the corundum is greater than or equal to 99 wt.%. Specifically, the particle size distribution of the corundum is as follows: particles smaller than 5 mm and greater than or equal to 3 mm account for 25 wt.% to 45 wt.%, particles smaller than 3 mm and greater than or equal to 1 mm account for 10 wt.% to 15 wt.%, particles smaller than 1 mm and greater than or equal to 0.088 mm account for 10 wt.% to 15 wt.%, particles smaller than 0.088 mm and greater than or equal to 0.045 mm account for 25 wt.% to 30 wt.%, and particles smaller than 0.045 mm account for 10 wt.% to 15 wt.%.

[0024] In this embodiment, the particle size distribution is calculated based on the Anderson equation. The rheological and flow properties of the material are determined by the jump table method and the self-flow value within 30 seconds. Finally, the particle size distribution of the spray material is determined to be a limiting particle size of 5 mm, q = 0.28, which can form the densest filling, and the aggregate ratio is 67%.

[0025] A second aspect of this application provides a method for preparing the above-mentioned aluminum-magnesium steel ladle wall spraying material, which includes weighing corundum, spinel, α-alumina micro powder, calcium aluminate cement, ρ-alumina and metallic aluminum powder according to the specified ratio, mixing them, and then weighing water-reducing agent and zirconium oxychloride according to the specified ratio and adding and stirring to obtain the aluminum-magnesium steel ladle wall spraying material.

[0026] A third aspect of this application provides the application of the above-mentioned aluminum-magnesium steel ladle wall spraying material in the repair of steel ladle walls.

[0027] Specifically, the application includes the following steps: adding water to the aluminum-magnesium steel ladle wall patching material, mixing, and pumping it for wet spraying onto the inner lining of the steel ladle wall. The patching material in this embodiment uses wet spraying, which differs from the dry spraying method in the prior art. It produces no dust pollution, allows for direct pumping of fluid, and has a lower material rebound rate than dry or semi-dry spraying. The pumped fluid adheres to the working lining surface, exhibiting superior physical properties at both room temperature and high temperature compared to dry or semi-dry spraying. This technical solution can fill with large particles as the upper limit of the particle size distribution in the aggregate, while the maximum particle size in dry or semi-dry spraying is currently generally below 3mm. Furthermore, compared to dry or semi-dry methods, this solution requires less water, enabling dust-free operation and is environmentally friendly.

[0028] The aforementioned aluminum-magnesium alloy ladle wall patching compound allows for repeated patching and maintenance during each working interval of the ladle, providing comprehensive and routine care for the ladle wall refractory material and extending its service life. It can also repair locally damaged ladle wall linings or increase the thickness of the lining in key areas, eliminating potential hazards and accidents related to the lining.

[0029] The present application will be further described below with reference to specific embodiments. All reagents in the following embodiments are commercially available.

[0030] Example 1

[0031] A type of aluminum-magnesium steel ladle wall spraying material, the raw materials of which include the following components by weight percentage: 51.8% corundum, 23% spinel, 15% α-alumina micro powder, 3% calcium aluminate cement, 2% ρ-alumina, 2% metallic aluminum powder, 0.2% water-reducing agent, and 3% zirconium oxychloride.

[0032] The corundum is tabular corundum. The Al2O3 content in the tabular corundum is ≥99 wt.%. The particle size distribution of the corundum is as follows: less than 5 mm and greater than or equal to 3 mm: 25 wt%; less than 3 mm and greater than or equal to 1 mm: 15 wt%; less than 1 mm and greater than or equal to 0.088 mm: 15 wt%; less than 0.088 mm and greater than or equal to 0.045 mm: 30 wt%; less than 0.045 mm: 15 wt%.

[0033] The spinel has an Al2O3 content ≥78wt% and an MgO content ≥21wt%. The particle size distribution of the spinel is: 55wt% for particles 1~0.088mm and 45wt% for particles smaller than 0.088mm.

[0034] The Al2O3 content of the α-alumina micro powder is ≥98wt%; the particle size of the α-alumina micro powder is ≤2μm.

[0035] The al₂O₃ content of ρ-alumina is ≥98 wt%; the particle size of ρ-alumina is ≤90 μm. The ZrOCl₂·8H₂O content of zirconium oxychloride is ≥98 wt%.

[0036] The aluminum content of the aluminum powder is ≥97wt%; the particle size of the aluminum powder is ≤0.075mm.

[0037] The water-reducing agent is a mixture of sodium tripolyphosphate and melamine.

[0038] The preparation method of the above-mentioned aluminum-magnesium steel ladle wall spraying material includes weighing corundum, spinel, α-alumina micro powder, calcium aluminate cement, ρ-alumina and metallic aluminum powder according to the proportion, mixing them, and then weighing water-reducing agent and zirconium oxychloride according to the proportion and adding them and stirring evenly to obtain the final product.

[0039] Add 5% water (by weight) to the above-mentioned aluminum-magnesium alloy steel ladle wall patching material, mix thoroughly, and pump and wet-spray onto the inner lining of the steel ladle wall. Cure at room temperature for 7 hours, demold, and bake at 110℃ for 30 hours. The inner lining of the sprayed steel ladle wall was tested, and its bulk density was found to be 3.05 g / cm³. 3 The compressive strength at room temperature is 26.6 MPa; the flexural strength at room temperature is 8.62 MPa; and the apparent porosity is 20.3%.

[0040] Example 2

[0041] A type of aluminum-magnesium alloy steel ladle wall spraying material comprises the following components by weight percentage: 53% corundum, 25% spinel, 14.9% α-alumina micro powder, 2% calcium aluminate cement, 2% p-alumina, 1% metallic aluminum powder, 0.1% water-reducing agent, and 2% zirconium oxychloride. The water-reducing agent is sodium hexametaphosphate.

[0042] The technical parameters of the raw materials, the preparation method of the spraying material, and the wet spraying method are the same as in Example 1.

[0043] The inner lining of the coated steel ladle wall was tested, and its bulk density was 3.08 g / cm³. 3 The compressive strength at room temperature is 28.2 MPa; the flexural strength at room temperature is 9.03 MPa; and the apparent porosity is 19.6%.

[0044] Example 3

[0045] A type of aluminum-magnesium alloy steel ladle wall spraying material comprises the following components by weight percentage: 54.2% corundum, 23.2% spinel, 10.5% α-alumina micro powder, 2% calcium aluminate cement, 4% p-alumina, 2% metallic aluminum powder, 0.1% water-reducing agent, and 4% zirconium oxychloride. The water-reducing agent is sodium polyacrylate.

[0046] The technical parameters of the raw materials, the preparation method of the spraying material, and the wet spraying method are the same as in Example 1.

[0047] The inner lining of the coated steel ladle was tested and found to have a bulk density of 3.11 g / cm³. 3 The compressive strength at room temperature is 28.5 MPa; the flexural strength at room temperature is 9.12; and the apparent porosity is 18.8%.

[0048] The test results from Examples 1 to 3 show that the ladle wall spraying material has the characteristics of good high-temperature mechanical strength, resistance to chemical corrosion, long service life and low production cost during use.

[0049] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A type of aluminum-magnesium steel ladle wall patching material, characterized in that, Its raw materials include the following components by weight percentage: 50%–55% corundum, 20%–25% spinel, 10%–15% α-alumina micro powder, 2%–4% calcium aluminate cement, 2%–4% ρ-alumina, 1%–2% metallic aluminum powder, 0.1%–0.2% water-reducing agent, and 2%–4% zirconium oxychloride; The content of Al2O3 in the p-alumina is greater than or equal to 98 wt.%; the particle size of the p-alumina is less than or equal to 90 μm. The particle size distribution of the corundum is as follows: particles smaller than 5 mm and greater than or equal to 3 mm account for 25 wt.% to 45 wt.%, particles smaller than 3 mm and greater than or equal to 1 mm account for 10 wt.% to 15 wt.%, particles smaller than 1 mm and greater than or equal to 0.088 mm account for 10 wt.% to 15 wt.%, particles smaller than 0.088 mm and greater than or equal to 0.045 mm account for 25 wt.% to 30 wt.%, and particles smaller than 0.045 mm account for 10 wt.% to 15 wt.%.

2. The aluminum-magnesium steel ladle wall patching material according to claim 1, characterized in that, The zirconium oxychloride contains ZrOCl2·8H2O at a content greater than or equal to 98 wt.%.

3. The aluminum-magnesium steel ladle wall patching material according to claim 1 or 2, characterized in that, The corundum is selected from one or more of dense corundum, brown corundum, white corundum, and tabular corundum, and the content of Al2O3 in the corundum is greater than or equal to 99 wt.%.

4. The aluminum-magnesium steel ladle wall patching material according to claim 1 or 2, characterized in that, The spinel contains an Al2O3 content greater than or equal to 78 wt.% and an MgO content greater than or equal to 21 wt.%. The particle size distribution of the spinel is: 40 wt.% to 60 wt.% of particles with a diameter of 1 to 0.088 mm and 40 wt.% to 60 wt.% of particles smaller than 0.088 mm.

5. The aluminum-magnesium steel ladle wall patching material according to claim 1 or 2, characterized in that, The α-alumina micro powder contains an Al2O3 content greater than or equal to 98 wt.% and a particle size less than or equal to 2 μm.

6. The aluminum-magnesium steel ladle wall patching material according to claim 1 or 2, characterized in that, The aluminum powder contains an Al content greater than or equal to 97 wt.%; the particle size of the aluminum powder is less than or equal to 0.075 mm; and / or The water-reducing agent is selected from one or more of sodium tripolyphosphate, sodium hexametaphosphate, sodium polyacrylate, and melamine.

7. The method for preparing the aluminum-magnesium steel ladle wall patching material according to any one of claims 1 to 6, characterized in that: The process involves weighing out corundum, spinel, α-alumina micro powder, calcium aluminate cement, ρ-alumina, and metallic aluminum powder according to the specified proportions, mixing them, and then weighing out water-reducing agent and zirconium oxychloride according to the specified proportions and adding them while stirring to obtain the aluminum-magnesium steel ladle wall spraying material.

8. The application of the aluminum-magnesium steel ladle wall patching material according to any one of claims 1 to 6 in the repair of steel ladle walls.

9. The application according to claim 8, characterized in that, The application includes the following steps: adding water to the aluminum-magnesium steel ladle wall patching material, mixing, and pumping wet spraying onto the inner lining of the steel ladle wall.