Magnesium ramming material for continuous casting tundish and preparation method of magnesium ramming material

Abstract

The invention relates to a magnesian ramming material for a continuous casting tundish and a preparation method of the magnesian ramming material. The magnesian ramming material comprises the following components in parts by weight: 70-90 parts of natural forsterite; 50 to 65 parts of medium-grade sintered magnesia; 25 to 40 parts of fused magnesite; 5-10 parts of phenolic resol; 3-5 parts of metal silicon powder; 2-3 parts of alumina micro powder; and 1-3 parts of chromium oxide green powder. The preparation method comprises the following steps: adding the natural forsterite, the medium-grade magnesite clinker and the fused magnesite into a stirrer according to the proportion, and stirring; then adding the metal silicon powder, the alumina micro powder and the chromium oxide green powder into a stirrer for stirring; finally, adding phenolic resol to form a mixture; and pouring the mixture into a mold, and ramming and sintering. According to the invention, a certain amount of chromium oxide green powder is added, and the chromium oxide green powder has relatively high fluidity and dispersibility, can be well filled in a mixed material, and is combined with the phenolic resol to enhance the gluing effect of the phenolic resol, so that the prepared ramming material has very good erosion resistance and erosion resistance.

Description

Technical Field

[0001] The invention relates to the technical field of refractory materials, and in particular to a magnesium ramming material for a continuous casting tundish and a preparation method thereof. Background Art

[0002] The continuous casting tundish is a refractory container located between the ladle and the crystallizer, mainly used for pouring molten steel. It first receives the molten steel injected by the ladle, and then distributes the molten steel to each crystallizer for cooling and solidification. It is an indispensable part of the steelmaking continuous casting process.

[0003] During the stay of molten steel in the tundish, the slag will corrode the wall of the tundish, and the molten steel will wash the wall of the tundish, which will affect the service life of the tundish. Therefore, when the continuous casting tundish is used, a ramming material layer will be laid to resist the scouring and corrosion of the molten steel on the wall of the tundish. However, there are still some problems with the current ramming materials during use, such as poor scouring resistance and easy erosion. Summary of the invention

[0004] In order to overcome the defects of the prior art, the technical problem solved by the present invention is to provide a magnesium ramming material for a continuous casting tundish and a preparation method thereof. The present invention can improve the corrosion resistance and scouring resistance of the ramming material by adding a certain amount of chromium oxide green powder.

[0005] In order to achieve the above object, the present invention adopts the following technical solutions:

[0006] A magnesium ramming material for a continuous casting tundish comprises the following components in parts by weight:

[0007] 70-90 parts of natural forsterite;

[0008] 50-65 parts of medium-grade sintered magnesia;

[0009] 25-40 parts of fused magnesia;

[0010] 5-10 parts of phenolic resol resin;

[0011] 3-5 parts of metallic silicon powder;

[0012] 2-3 parts of alumina powder;

[0013] 1 to 3 parts of chromium oxide green powder.

[0014] The mass percentage of MgO in the natural forsterite is 40% to 45%, and the mass percentage of SiO2 is 40% to 45%. The MgO content in the mid-range sintered magnesia is ≥93%; the MgO content in the fused magnesia is ≥95%.

[0015] The weight ratio of the natural forsterite with a particle size of 1 to 3 mm, 0.074 to 1 mm, and ≤ 0.074 mm is (5 to 10): (2 to 5): (3 to 5).

[0016] The weight ratio of the medium-grade sintered magnesia with particle sizes of 1-3 mm, 0.074-1 mm, and ≤0.074 mm is (5-10): (4-8): (6-12).

[0017] The weight ratio of the particle sizes of 1-3 mm, 0.074-1 mm, and ≤0.074 mm in the fused magnesia is (5-8): (3-5): (6-10).

[0018] The silicon content of the metal silicon powder is ≥98%; the particle size of the metal silicon powder is ≤325 meshes.

[0019] The Al2O3 content of the alumina micropowder is ≥98%; and the particle size of the alumina micropowder is ≤325 meshes.

[0020] The chromium oxide green powder has a particle size of ≤325 mesh.

[0021] The weight ratio of the metallic silicon powder to the alumina powder is 1:2.

[0022] A method for preparing a magnesium ramming material for a continuous casting tundish, the specific steps are as follows:

[0023] 1) According to the above-mentioned proportions, natural forsterite, medium-grade sintered magnesia and fused magnesia are added into a mixer and stirred for 15 to 20 minutes;

[0024] 2) Then add metallic silicon powder, aluminum oxide powder and chromium oxide green powder into a mixer and stir for 10 to 15 minutes; finally add phenolic resol A resin and stir for 15 to 20 minutes to form a mixture;

[0025] 3) Pour the mixture into a mold, pound and vibrate it, and sinter the compacted material.

[0026] Compared with the prior art, the present invention has the following beneficial effects:

[0027] The invention adds a certain amount of chromium oxide green powder, which has high fluidity and dispersibility and can be well filled in the mixed material, and cooperates with the phenolic resol resin to increase the bonding effect of the phenolic resol resin, so that the prepared ramming material has good corrosion resistance and scouring resistance. DETAILED DESCRIPTION

[0028] The specific embodiments of the present invention are further described below:

[0029] Example 1

[0030] A magnesium ramming material for a continuous casting tundish comprises the following components in parts by weight:

[0031] 75 parts of natural forsterite;

[0032] 52 parts of medium-grade sintered magnesia;

[0033] 27 parts of fused magnesia;

[0034] 6 parts of phenolic resol resin;

[0035] 3.5 parts of metallic silicon powder;

[0036] 2 parts of alumina powder;

[0037] 1.5 parts of chromium oxide green powder.

[0038] The mass percentage of MgO in the natural forsterite is 40% to 45%, and the mass percentage of SiO2 is 40% to 45%. The MgO content in the mid-range sintered magnesia is ≥93%; the MgO content in the fused magnesia is ≥95%.

[0039] The weight ratio of the natural forsterite particle sizes of 1-3 mm, 0.074-1 mm, and ≤0.074 mm is 6:3:4.

[0040] The weight ratio of the medium-grade sintered magnesia grain sizes of 1-3 mm, 0.074-1 mm, and ≤0.074 mm is 8:5:8.

[0041] The weight ratio of the particle sizes of 1-3 mm, 0.074-1 mm, and ≤0.074 mm in the fused magnesia is 5:4:8.

[0042] The silicon content of the metal silicon powder is ≥98%; the particle size of the metal silicon powder is ≤325 meshes.

[0043] The Al2O3 content of the alumina micropowder is ≥98%; and the particle size of the alumina micropowder is ≤325 meshes.

[0044] The chromium oxide green powder has a particle size of ≤325 mesh.

[0045] The weight ratio of the metallic silicon powder to the alumina powder is 1:2.

[0046] A method for preparing a magnesium ramming material for a continuous casting tundish, the specific steps are as follows:

[0047] 1) According to the above-mentioned proportions, natural forsterite, medium-grade sintered magnesia and fused magnesia are added into a mixer and stirred for 15 minutes;

[0048] 2) Then add metallic silicon powder, aluminum oxide powder and chromium oxide green powder into a blender and stir for 10 minutes; finally add phenolic resol resin and stir for 20 minutes to form a mixture;

[0049] 3) Pour the mixture into a mold, pound and vibrate it, and sinter the compacted material.

[0050] Example 2

[0051] A magnesium ramming material for a continuous casting tundish comprises the following components in parts by weight:

[0052] 85 parts of natural forsterite;

[0053] 60 parts of medium-grade sintered magnesia;

[0054] 30 parts of fused magnesia;

[0055] 8 parts of phenolic resol resin;

[0056] 4.5 parts of metallic silicon powder;

[0057] 2.5 parts of alumina powder;

[0058] 3 parts of chromium oxide green powder.

[0059] The mass percentage of MgO in the natural forsterite is 40% to 45%, and the mass percentage of SiO2 is 40% to 45%. The MgO content in the mid-range sintered magnesia is ≥93%; the MgO content in the fused magnesia is ≥95%.

[0060] The weight ratio of the natural forsterite with a particle size of 1 to 3 mm, 0.074 to 1 mm, and ≤ 0.074 mm is 9:4:3

[0061] The weight ratio of the medium-grade sintered magnesia grain sizes of 1-3 mm, 0.074-1 mm, and ≤0.074 mm is 8:5:10.

[0062] The weight ratio of the particle sizes of 1-3 mm, 0.074-1 mm, and ≤0.074 mm in the fused magnesia is 5:4:9.

[0063] The silicon content of the metal silicon powder is ≥98%; the particle size of the metal silicon powder is ≤325 meshes.

[0064] The Al2O3 content of the alumina micropowder is ≥98%; and the particle size of the alumina micropowder is ≤325 meshes.

[0065] The chromium oxide green powder has a particle size of ≤325 mesh.

[0066] The weight ratio of the metallic silicon powder to the alumina powder is 1:2.

[0067] A method for preparing a magnesium ramming material for a continuous casting tundish, the specific steps are as follows:

[0068] 1) According to the above-mentioned proportions, natural forsterite, medium-grade sintered magnesia and fused magnesia are added into a mixer and stirred for 15 minutes;

[0069] 2) Then add metallic silicon powder, aluminum oxide powder and chromium oxide green powder into a blender and stir for 10 minutes; finally add phenolic resol resin and stir for 20 minutes to form a mixture;

[0070] 3) Pour the mixture into a mold, pound and vibrate it, and sinter the compacted material.

[0071] The preferred embodiments of the present invention are described in detail above, but the present invention is not limited to the specific details in the above embodiments. Within the technical concept of the present invention, the technical solution of the present invention can be subjected to a variety of simple modifications, and these simple modifications all belong to the protection scope of the present invention. It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. In order to avoid unnecessary repetition, the present invention will not further describe various possible combinations. In addition, the various different embodiments of the present invention can also be arbitrarily combined, as long as they do not violate the concept of the present invention, they should also be regarded as the contents disclosed by the present invention.

Claims

1. A magnesium ramming mass for continuous casting tundish, characterized in that: Contains the following components in parts by weight: 70-90 parts of natural forsterite; 50-65 parts of medium-grade sintered magnesia; 25-40 parts of fused magnesia; 5-10 parts of phenolic resol resin; 3-5 parts of metallic silicon powder; 2-3 parts of alumina powder; 1 to 3 parts of chromium oxide green powder.

2. The magnesium ramming material for continuous casting tundish according to claim 1, characterized in that: The mass percentage of MgO in the natural forsterite is 40% to 45%, and the mass percentage of SiO2 is 40% to 45%; the MgO content in the mid-range sintered magnesia is ≥93%; and the MgO content in the fused magnesia is ≥95%.

3. A magnesium ramming material for continuous casting tundish according to claim 1 or 2, characterized in that: The weight ratio of the natural forsterite with a particle size of 1 to 3 mm, 0.074 to 1 mm, and ≤ 0.074 mm is (5 to 10): (2 to 5): (3 to 5).

4. A magnesium ramming material for continuous casting tundish according to claim 1 or 2, characterized in that: The weight ratio of the medium-grade sintered magnesia with particle sizes of 1-3 mm, 0.074-1 mm, and ≤0.074 mm is (5-10): (4-8): (6-12).

5. A magnesium ramming mass for continuous casting tundish according to claim 1 or 2, characterized in that: The weight ratio of the particle sizes of 1-3 mm, 0.074-1 mm, and ≤0.074 mm in the fused magnesia is (5-8): (3-5): (6-10).

6. The magnesium ramming material for continuous casting tundish according to claim 1, characterized in that: The silicon content of the metal silicon powder is ≥98%; the particle size of the metal silicon powder is ≤325 meshes.

7. The magnesium ramming material for continuous casting tundish according to claim 1, characterized in that: The Al2O3 content of the alumina micropowder is ≥98%; and the particle size of the alumina micropowder is ≤325 meshes.

8. The magnesium ramming mass for continuous casting tundish according to claim 1, characterized in that: The chromium oxide green powder has a particle size of ≤325 mesh.

9. The magnesium ramming mass for continuous casting tundish according to claim 1, characterized in that: The weight ratio of the metallic silicon powder to the alumina powder is 1:

2.

10. A method for preparing a magnesium ramming mass for continuous casting tundish as claimed in claim 1, characterized in that: The specific steps are as follows: 1) According to the above-mentioned proportions, natural forsterite, medium-grade sintered magnesia and fused magnesia are added into a mixer and stirred for 15 to 20 minutes; 2) Then add metallic silicon powder, aluminum oxide powder and chromium oxide green powder into a mixer and stir for 10 to 15 minutes; finally add phenolic resol A resin and stir for 15 to 20 minutes to form a mixture; The mixed material is poured into a mold, rammed and vibrated, and the rammed and compacted material is sintered.