阅读说明：本技术 一种钢包抗侵蚀镁质耐火泥浆及其制备方法 (Ladle anti-erosion magnesia refractory mortar and preparation method thereof ) 是由 王团收 刘丽 张盛 贾祥超 任林 颜浩 刘静轩 李健 崔志强 付杰豪 于 2021-02-05 设计创作，主要内容包括：本发明提供一种钢包抗侵蚀镁质耐火泥浆及其制备方法,钢包抗侵蚀镁质耐火泥浆,按照质量份数计算,其制备原料包括以下组分：电熔镁砂40-120份、氧化铝微粉1-15份、氧化铬细粉0.5-8份、氧化锆细粉0.5-8份、碳化硅细粉0.5-8份、碳化硼细粉0.3-4份、分散剂0.1-2份、增黏剂0.1-2份。该钢包抗侵蚀镁质耐火泥浆耐钢水冲刷与耐钢渣侵蚀的效果好,可解决钢包在VOD精炼过程中砖缝部位残厚较低与夹钢的问题。(The invention provides ladle anti-erosion magnesia refractory mortar and a preparation method thereof, wherein the ladle anti-erosion magnesia refractory mortar comprises the following preparation raw materials in parts by mass: 40-120 parts of fused magnesia, 1-15 parts of alumina micropowder, 0.5-8 parts of chromium oxide fine powder, 0.5-8 parts of zirconia fine powder, 0.5-8 parts of silicon carbide fine powder, 0.3-4 parts of boron carbide fine powder, 0.1-2 parts of dispersant and 0.1-2 parts of tackifier. The ladle anti-erosion magnesia refractory mortar has good molten steel erosion resistance and steel slag erosion resistance, and can solve the problems of low residual thickness and steel inclusion of a brick joint part of a ladle in the VOD refining process.)

1. The ladle anti-erosion magnesia refractory mortar is characterized by comprising the following preparation raw materials in parts by mass:

40-120 parts of fused magnesia, 1-15 parts of alumina micropowder, 0.5-8 parts of chromium oxide fine powder, 0.5-8 parts of zirconia fine powder, 0.5-8 parts of silicon carbide fine powder, 0.3-4 parts of boron carbide fine powder, 0.1-2 parts of dispersant and 0.1-2 parts of tackifier.

2. The ladle anti-corrosion magnesia refractory mortar according to claim 1, wherein the preparation raw materials comprise the following components in parts by weight:

80-90 parts of fused magnesia, 2-8 parts of alumina micro powder, 1-5 parts of chromium oxide fine powder, 1-4 parts of zirconia fine powder, 1-4 parts of silicon carbide fine powder, 0.5-2 parts of boron carbide fine powder, 0.2-0.6 part of dispersant and 0.5-1 part of tackifier.

3. The ladle erosion-resistant magnesium refractory mortar of claim 1, wherein:

the particle size of the fused magnesia is 0.045-0.074 mm; the particle size of the alumina micro powder is 1-3 mu m; the particle size of the chromium oxide fine powder is 0.045-0.074 mm; the particle size of the zirconia fine powder is 0.045-0.074 mm; the grain diameter of the silicon carbide fine powder is 0.045-0.074 mm; the particle size of the boron carbide fine powder is 0.045-0.074 mm.

4. The ladle erosion-resistant magnesium refractory mortar of claim 1, wherein:

the dispersing agent is sodium tripolyphosphate.

5. The ladle erosion-resistant magnesium refractory mortar of claim 1, wherein:

the tackifier is one or the mixture of two of sodium carboxymethyl cellulose and calcium lignosulphonate.

6. The ladle erosion-resistant magnesium refractory mortar of claim 1, wherein:

the mass ratio of the zirconium oxide fine powder to the silicon carbide fine powder to the boron carbide fine powder is (2-4): (2-4): (1-2).

7. The ladle erosion-resistant magnesium refractory mortar of claim 1, wherein:

the content of MgO in the fused magnesia is more than 98wt%, the content of CaO in the fused magnesia is less than 1.5wt%, and Fe in the fused magnesia₂O₃Is less than 0.5 wt%.

8. The ladle erosion-resistant magnesium refractory mortar of claim 1, wherein:

al in the alumina micro powder₂O₃Is greater than 99 wt%; cr in the chromium oxide fine powder₂O₃The content of (B) is more than 99 wt%.

9. The ladle erosion-resistant magnesium refractory mortar of claim 1, wherein:

ZrO in the fine zirconia powder₂Is greater than 95 wt%; the content of SiC in the silicon carbide fine powder is more than 97 wt%; b in the boron carbide fine powder₄The content of C is more than 95 wt%.

10. A method of preparing the ladle erosion resistant magnesium refractory slurry of any one of claims 1 to 9, comprising the steps of:

mixing the preparation raw material of the ladle anti-erosion magnesia refractory mortar with water, and stirring to obtain the ladle anti-erosion magnesia refractory mortar, wherein the mass of the water is 30-35% of the total mass of the preparation raw material of the ladle anti-erosion magnesia refractory mortar.

Technical Field

The invention belongs to the technical field of refractory materials, and particularly relates to ladle anti-erosion magnesia refractory mortar and a preparation method thereof.

Background

Along with the increase of the market demand on high-quality steel products, the refining requirements of steel plants on molten steel are higher and higher, ladle VOD refining is a common refining mode in China and is the most serious in ladle brick erosion, a ladle is in a vacuum environment in the VOD refining process, and the molten steel is most severely eroded on refractory materials in the vacuumizing process. The brickwork joint of the brickwork ladle is a channel for exhausting, and the brickwork joint part is most easily scoured and eroded. The residual thickness of the ladle brick is not difficult to see, the lowest part of the residual thickness of the ladle brick is a brick joint, the effect that common refractory mortar bears molten steel scouring and steel slag erosion under a VOD refining environment is poorer, and the residual thickness of the brick joint is about 15-20 mm lower than the residual thickness of a ladle brick body. In addition, the common refractory mortar has large water addition amount, generates shrinkage at high temperature, is difficult to fill brick joints completely, and is easy to generate molten steel infiltration and steel clamping at the brick joints.

Disclosure of Invention

The invention aims to provide ladle erosion-resistant magnesia refractory slurry and a preparation method thereof, which have good molten steel erosion resistance and steel slag erosion resistance and can solve the problems of low residual thickness and steel inclusion of a brick joint part of a ladle in a VOD refining process.

In order to solve the problems, one aspect of the invention provides ladle anti-corrosion magnesia refractory slurry, which comprises the following preparation raw materials in parts by weight:

40-120 parts of fused magnesia, 1-15 parts of alumina micropowder, 0.5-8 parts of chromium oxide fine powder, 0.5-8 parts of zirconia fine powder, 0.5-8 parts of silicon carbide fine powder, 0.3-4 parts of boron carbide fine powder, 0.1-2 parts of dispersant and 0.1-2 parts of tackifier.

The ladle anti-erosion magnesia refractory slurry adopts high-grade fused magnesia as a main raw material, and the magnesia material can effectively improve the anti-erosion performance of the slurry. Alumina micropowder and chromium oxide fine powder are added in an auxiliary manner, the alumina micropowder and the chromium oxide fine powder can generate magnesia-alumina spinel and magnesia-chromium spinel in situ with magnesia at high temperature, the thermal shock stability of the two spinels is good, the stripping resistance of slurry can be improved, the slag corrosion resistance of the slurry can be further improved by the spinels, and the volume of the slurry can be increased along with the generation of the two spinels, the volume shrinkage caused by the loss of moisture of the slurry can be offset, so that the slurry at the brick joint is fuller, and the risk of steel clamping at the brick joint is reduced. The zirconium oxide fine powder, the boron carbide fine powder and the silicon carbide fine powder are added in an auxiliary manner, the melting points of the three fine powders are above 2000 ℃, the high-temperature resistance chemical property is stable, and the erosion resistance of the slurry can be improved. In addition, the volume expansion of the zirconia generated when the monoclinic crystal is converted into the tetragonal crystal can also compensate the cracks possibly generated after the slurry is shrunk. More importantly, ZrB can be formed by adding the three materials simultaneously₂The composite SiC material has high heat conductivity and elastic modulus, excellent thermal shock stability and less thermal shock stripping of slurry. At the same time, ZrB₂the-SiC complex phase material is also an oxidation resistant material with good effect, and the boride can also form a glass phase at about 1100 ℃, so that oxygen is prevented from diffusing into brick joints at the joint of the slurry and the magnesia carbon brick, and the magnesia carbon brick is prevented from being oxidized.

Preferably, the preparation raw materials comprise the following components in parts by weight:

80-90 parts of fused magnesia, 2-8 parts of alumina micro powder, 1-5 parts of chromium oxide fine powder, 1-4 parts of zirconia fine powder, 1-4 parts of silicon carbide fine powder, 0.5-2 parts of boron carbide fine powder, 0.2-0.6 part of dispersant and 0.5-1 part of tackifier.

A large number of experimental trials find that when the components in the preparation raw materials are selected within the range, the ladle anti-corrosion magnesia refractory mortar has the best anti-stripping performance and slag corrosion performance, the residual thickness of the brick joint and the residual thickness difference of the magnesia carbon brick are optimum after the ladle is offline during the building of the VOD ladle, and no steel inclusion is found in the brick joint of the ladle brick.

Preferably, the particle size of the fused magnesia is 0.045-0.074 mm; the particle size of the alumina micro powder is 1-3 mu m; the particle size of the chromium oxide fine powder is 0.045-0.074 mm; the particle size of the zirconia fine powder is 0.045-0.074 mm; the grain diameter of the silicon carbide fine powder is 0.045-0.074 mm; the particle size of the boron carbide fine powder is 0.045-0.074 mm.

Preferably, the dispersant is sodium tripolyphosphate.

Preferably, the tackifier is one or a mixture of two of sodium carboxymethyl cellulose and calcium lignosulfonate.

Preferably, the mass ratio of the zirconium oxide fine powder, the silicon carbide fine powder and the boron carbide fine powder is (2-4): (2-4): (1-2). When the fine powder of zirconium oxide, the fine powder of silicon carbide and the fine powder of boron carbide are added in the above-mentioned mass ratio, ZrB can be formed₂the-SiC complex phase structure is most suitable, and the thermal shock stability of the ladle anti-erosion magnesia refractory slurry is further improved.

Preferably, the content of MgO in the fused magnesia is more than 98wt%, the content of CaO is less than 1.5wt%, and Fe₂O₃Is less than 0.5 wt%.

Preferably, Al in the alumina micro powder₂O₃Is greater than 99 wt%; cr in the chromium oxide fine powder₂O₃The content of (B) is more than 99 wt%.

Preferably, ZrO in the fine zirconia powder₂Is greater than 95 wt%; the content of SiC in the silicon carbide fine powder is more than 97 wt%; b in the boron carbide fine powder₄The content of C is more than 95 wt%.

In another aspect of the present invention, there is provided a method for preparing the above ladle erosion-resistant magnesia refractory mortar, comprising the steps of:

mixing the preparation raw material of the ladle anti-erosion magnesia refractory mortar with water, and stirring to obtain the ladle anti-erosion magnesia refractory mortar, wherein the mass of the water is 30-35% of the total mass of the preparation raw material of the ladle anti-erosion magnesia refractory mortar.

Compared with the prior art, the invention has the following beneficial effects:

1. the ladle anti-erosion magnesia refractory slurry adopts high-grade fused magnesia as a main raw material, and the magnesia material can effectively improve the anti-erosion performance of the slurry.

2. The ladle anti-erosion magnesia refractory slurry is added with alumina micro powder and chromium oxide fine powder in an auxiliary way, the alumina micro powder and the chromium oxide fine powder can generate magnesia-alumina spinel and magnesia-chromium spinel in situ with magnesia at high temperature, the thermal shock stability of the two spinels is good, the anti-stripping performance of the slurry can be improved, the slag erosion resistance of the slurry can be further improved by the spinels, and the volume shrinkage caused by the loss of water in the slurry can be counteracted along with the increase of the volume of the slurry along with the generation of the two spinels, so that the slurry at brick joints is fuller, and the risk of steel clamping at the brick joints is reduced.

3. The ladle anti-erosion magnesia refractory mortar also has the auxiliary addition of zirconia fine powder, boron carbide fine powder and silicon carbide fine powder. (1) The melting points of the three fine powders are above 2000 ℃, the fine powders are stable in high-temperature resistance and chemical property, and the erosion resistance of the slurry can be improved. (2) The volume expansion of the zirconia generated when the monoclinic crystal is converted into the tetragonal crystal can also compensate the cracks possibly generated after the slurry is contracted. (3) ZrB can be formed by adding the three materials simultaneously₂The composite SiC material has high heat conductivity and elastic modulus, excellent thermal shock stability and less thermal shock stripping of slurry. At the same time, ZrB₂the-SiC complex phase material is also an oxidation resistant material with good effect, and the boride can also form a glass phase at about 1100 ℃, so that oxygen is prevented from diffusing into brick joints at the joint of the slurry and the magnesia carbon brick, and the magnesia carbon brick is prevented from being oxidized.

Detailed Description

The technical solutions of the present invention will be described clearly and completely with reference to the following embodiments of the present invention, and it should be understood that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Example 1

The ladle anti-erosion magnesia refractory mortar is prepared from the following raw materials in parts by mass:

87 parts of fused magnesia with the grain diameter of 0.045-0.074mm, 2 parts of alumina micropowder with the grain diameter of 1-3 mu m, 5 parts of chromium oxide fine powder with the grain diameter of 0.045-0.074mm, 2 parts of zirconia fine powder with the grain diameter of 0.045-0.074mm, 2 parts of silicon carbide fine powder with the grain diameter of 0.045-0.074mm, 0.9 part of boron carbide fine powder with the grain diameter of 0.045-0.074mm, 0.6 part of sodium tripolyphosphate serving as a dispersant and 0.5 part of carboxymethylcellulose sodium serving as a tackifier.

The content of MgO in the fused magnesia is more than 98wt%, the content of CaO is less than 1.5wt%, and Fe₂O₃Less than 0.5 wt%; al in alumina micropowder₂O₃Is greater than 99 wt%; cr in chromium oxide fine powder₂O₃Is greater than 99 wt%; ZrO in zirconia fine powder₂Is greater than 95 wt%; the SiC content in the silicon carbide fine powder is more than 97 wt%; b in fine boron carbide powder₄The content of C is more than 95 wt%.

The preparation method of the ladle erosion-resistant magnesia refractory mortar comprises the following steps:

according to the selected mass portions, mixing the preparation raw materials of the ladle anti-erosion magnesium refractory slurry, adding the mixture into a stirrer to stir for 3 minutes to obtain a uniform mixture, then adding water accounting for 35 percent of the total weight of the mixture into the mixture, and continuing stirring for 5 minutes until the mixture becomes uniform slurry, thus obtaining the ladle anti-erosion magnesium refractory slurry.

The ladle anti-erosion magnesia refractory mortar is used when a VOD ladle is built, the difference between the residual thickness of a brick joint and the residual thickness of a magnesia carbon brick is 5mm after the ladle is offline, steel clamping is not seen in the brick joint of the ladle brick, the residual thickness of a working layer at the brick joint can be improved by the refractory mortar, the penetration of molten steel can be blocked, and the refractory mortar meets the use requirement of the VOD ladle.

Example 2

The ladle anti-erosion magnesia refractory mortar is prepared from the following raw materials in parts by mass:

80 parts of fused magnesia with the grain diameter of 0.045-0.074mm, 8 parts of alumina micropowder with the grain diameter of 1-3 mu m, 4 parts of chromium oxide fine powder with the grain diameter of 0.045-0.074mm, 3 parts of zirconia fine powder with the grain diameter of 0.045-0.074mm, 3 parts of silicon carbide fine powder with the grain diameter of 0.045-0.074mm, 1.3 parts of boron carbide fine powder with the grain diameter of 0.045-0.074mm, 0.2 part of sodium tripolyphosphate serving as a dispersant and 0.5 part of carboxymethylcellulose sodium serving as a tackifier.

The content of MgO in the fused magnesia is more than 98wt%, the content of CaO is less than 1.5wt%, and Fe₂O₃Less than 0.5 wt%; al in alumina micropowder₂O₃Is greater than 99 wt%; cr in chromium oxide fine powder₂O₃Is greater than 99 wt%; ZrO in zirconia fine powder₂Is greater than 95 wt%; the SiC content in the silicon carbide fine powder is more than 97 wt%; b in fine boron carbide powder₄The content of C is more than 95 wt%.

The preparation method of the ladle erosion-resistant magnesia refractory mortar comprises the following steps:

according to the selected mass portions, mixing the preparation raw materials of the ladle anti-erosion magnesium refractory slurry, adding the mixture into a stirrer to stir for 3 minutes to obtain a uniform mixture, then adding water accounting for 35 percent of the total weight of the mixture into the mixture, and continuing stirring for 5 minutes until the mixture becomes uniform slurry, thus obtaining the ladle anti-erosion magnesium refractory slurry.

The ladle anti-erosion magnesia refractory mortar is used when a VOD ladle is built, the difference between the residual thickness of a brick joint and the residual thickness of a magnesia carbon brick is 4mm after the ladle is offline, steel clamping is not seen in the brick joint of the ladle brick, the residual thickness of a working layer at the brick joint can be improved by the refractory mortar, the penetration of molten steel can be blocked, and the refractory mortar meets the use requirement of the VOD ladle.

Example 3

The ladle anti-erosion magnesia refractory mortar is prepared from the following raw materials in parts by mass:

80 parts of fused magnesia with the grain diameter of 0.045-0.074mm, 8 parts of alumina micropowder with the grain diameter of 1-3 mu m, 4 parts of chromium oxide fine powder with the grain diameter of 0.045-0.074mm, 3 parts of zirconia fine powder with the grain diameter of 0.045-0.074mm, 2.4 parts of silicon carbide fine powder with the grain diameter of 0.045-0.074mm, 1.4 parts of boron carbide fine powder with the grain diameter of 0.045-0.074mm, 0.2 part of sodium tripolyphosphate serving as a dispersant and 1 part of carboxymethyl cellulose sodium serving as a tackifier.

The content of MgO in the fused magnesia is more than 98wt%, the content of CaO is less than 1.5wt%, and Fe₂O₃Less than 0.5 wt%; al in alumina micropowder₂O₃Is greater than 99 wt%; cr in chromium oxide fine powder₂O₃Is greater than 99 wt%; ZrO in zirconia fine powder₂Is greater than 95 wt%; the SiC content in the silicon carbide fine powder is more than 97 wt%; b in fine boron carbide powder₄The content of C is more than 95 wt%.

The preparation method of the ladle erosion-resistant magnesia refractory mortar comprises the following steps:

according to the selected mass portions, mixing the preparation raw materials of the ladle anti-erosion magnesium refractory slurry, adding the mixture into a stirrer to stir for 3 minutes to obtain a uniform mixture, then adding water accounting for 35 percent of the total weight of the mixture into the mixture, and continuing stirring for 5 minutes until the mixture becomes uniform slurry, thus obtaining the ladle anti-erosion magnesium refractory slurry.

The ladle anti-erosion magnesia refractory mortar is used when a VOD ladle is built, the difference between the residual thickness of a brick joint and the residual thickness of a magnesia carbon brick is 4mm after the ladle is offline, steel clamping is not seen in the brick joint of the ladle brick, the residual thickness of a working layer at the brick joint can be improved by the refractory mortar, the penetration of molten steel can be blocked, and the refractory mortar meets the use requirement of the VOD ladle.

Example 4

The ladle anti-erosion magnesia refractory mortar is prepared from the following raw materials in parts by mass:

86 parts of fused magnesia with the grain diameter of 0.045-0.074mm, 2 parts of alumina micropowder with the grain diameter of 1-3 mu m, 4 parts of chromium oxide fine powder with the grain diameter of 0.045-0.074mm, 3 parts of zirconia fine powder with the grain diameter of 0.045-0.074mm, 3 parts of silicon carbide fine powder with the grain diameter of 0.045-0.074mm, 1.2 parts of boron carbide fine powder with the grain diameter of 0.045-0.074mm, 0.2 part of sodium tripolyphosphate serving as a dispersant, 0.4 part of calcium lignosulfonate serving as a tackifier and 0.2 part of carboxymethylcellulose sodium serving as a tackifier.

The content of MgO in the fused magnesia is more than 98wt%, the content of CaO is less than 1.5wt%, and Fe₂O₃Less than 0.5 wt%; al in alumina micropowder₂O₃Is greater than 99 wt%; cr in chromium oxide fine powder₂O₃Is greater than 99 wt%; ZrO in zirconia fine powder₂Is greater than 95 wt%; the SiC content in the silicon carbide fine powder is more than 97 wt%; b in fine boron carbide powder₄The content of C is more than 95 wt%.

The preparation method of the ladle erosion-resistant magnesia refractory mortar comprises the following steps:

according to the selected mass portions, mixing the preparation raw materials of the ladle anti-erosion magnesium refractory slurry, adding the mixture into a stirrer to stir for 3 minutes to obtain a uniform mixture, then adding water accounting for 32 percent of the total weight of the mixture into the mixture, and continuing stirring for 5 minutes until the mixture becomes uniform slurry, thus obtaining the ladle anti-erosion magnesium refractory slurry.

The ladle anti-erosion magnesia refractory mortar is used when a VOD ladle is built, the difference between the residual thickness of a brick joint and the residual thickness of a magnesia carbon brick is 6mm after the ladle is offline, no steel clip is seen in the brick joint of the ladle brick, the refractory mortar can improve the residual thickness of a working layer at the brick joint, the penetration of molten steel can be blocked, and the refractory mortar meets the use requirement of the VOD ladle.

Example 5

The ladle anti-erosion magnesia refractory mortar is prepared from the following raw materials in parts by mass:

90 parts of fused magnesia with the grain diameter of 0.045-0.074mm, 3.3 parts of alumina micropowder with the grain diameter of 1-3 mu m, 3 parts of chromium oxide fine powder with the grain diameter of 0.045-0.074mm, 1 part of zirconia fine powder with the grain diameter of 0.045-0.074mm, 1 part of silicon carbide fine powder with the grain diameter of 0.045-0.074mm, 0.5 part of boron carbide fine powder with the grain diameter of 0.045-0.074mm, 0.2 part of sodium tripolyphosphate serving as a dispersant, 0.5 part of calcium lignosulfonate serving as a tackifier and 0.5 part of carboxymethylcellulose sodium serving as a tackifier.

The content of MgO in the fused magnesia is more than 98wt%, the content of CaO is less than 1.5wt%, and Fe₂O₃Less than 0.5 wt%; al in alumina micropowder₂O₃Of (1) containsIn an amount greater than 99 wt%; cr in chromium oxide fine powder₂O₃Is greater than 99 wt%; ZrO in zirconia fine powder₂Is greater than 95 wt%; the SiC content in the silicon carbide fine powder is more than 97 wt%; b in fine boron carbide powder₄The content of C is more than 95 wt%.

The preparation method of the ladle erosion-resistant magnesia refractory mortar comprises the following steps:

according to the selected mass portions, mixing the preparation raw materials of the ladle anti-erosion magnesium refractory slurry, adding the mixture into a stirrer to stir for 3 minutes to obtain a uniform mixture, then adding water accounting for 35 percent of the total weight of the mixture into the mixture, and continuing stirring for 5 minutes until the mixture becomes uniform slurry, thus obtaining the ladle anti-erosion magnesium refractory slurry.

The ladle anti-erosion magnesia refractory mortar is used when a VOD ladle is built, the difference between the residual thickness of a brick joint and the residual thickness of a magnesia carbon brick is 4mm after the ladle is offline, steel clamping is not seen in the brick joint of the ladle brick, the residual thickness of a working layer at the brick joint can be improved by the refractory mortar, the penetration of molten steel can be blocked, and the refractory mortar meets the use requirement of the VOD ladle.

Example 6

The ladle anti-erosion magnesia refractory mortar is prepared from the following raw materials in parts by mass:

85 parts of fused magnesite with the grain diameter of 0.045-0.074mm, 5 parts of alumina micro powder with the grain diameter of 1-3 mu m, 1 part of chromium oxide fine powder with the grain diameter of 0.045-0.074mm, 4 parts of zirconium oxide fine powder with the grain diameter of 0.045-0.074mm, 4 parts of silicon carbide fine powder with the grain diameter of 0.045-0.074mm, 2 parts of boron carbide fine powder with the grain diameter of 0.045-0.074mm, 0.3 part of sodium tripolyphosphate serving as a dispersant and 0.5 part of calcium lignosulfonate serving as a tackifier.

The content of MgO in the fused magnesia is more than 98wt%, the content of CaO is less than 1.5wt%, and Fe₂O₃Less than 0.5 wt%; al in alumina micropowder₂O₃Is greater than 99 wt%; cr in chromium oxide fine powder₂O₃Is greater than 99 wt%; ZrO in zirconia fine powder₂Is greater than 95 wt%; the SiC content in the silicon carbide fine powder is more than 97 wt%; b in fine boron carbide powder₄The content of C is more than 95 wt%.

The preparation method of the ladle erosion-resistant magnesia refractory mortar comprises the following steps:

according to the selected mass portions, mixing the preparation raw materials of the ladle anti-erosion magnesium refractory slurry, adding the mixture into a stirrer to stir for 3 minutes to obtain a uniform mixture, then adding water accounting for 35 percent of the total weight of the mixture into the mixture, and continuing stirring for 5 minutes until the mixture becomes uniform slurry, thus obtaining the ladle anti-erosion magnesium refractory slurry.

The ladle anti-erosion magnesia refractory mortar is used when a VOD ladle is built, the difference between the residual thickness of a brick joint and the residual thickness of a magnesia carbon brick is 7mm after the ladle is offline, no steel clip is seen in the brick joint of the ladle brick, the refractory mortar can improve the residual thickness of a working layer at the brick joint, the penetration of molten steel can be blocked, and the refractory mortar meets the use requirement of the VOD ladle.

Example 7

The preparation raw materials of the ladle erosion-resistant magnesia refractory slurry are the same as those in example 1, except that 5 parts of zirconia fine powder with the particle size of 0.045-0.074mm, 5 parts of silicon carbide fine powder with the particle size of 0.045-0.074mm and 1 part of boron carbide fine powder with the particle size of 0.045-0.074mm are used. The preparation method of the ladle corrosion-resistant magnesia refractory mortar of the embodiment is the same as that of the embodiment 1.

The ladle anti-erosion magnesia refractory mortar is used when a VOD ladle is built, the difference between the residual thickness of a brick joint and the residual thickness of a magnesia carbon brick is 15mm after the ladle is offline, and a small amount of steel is clamped in the brick joint of the ladle brick.

Example 8

The ladle anti-erosion magnesia refractory mortar is prepared from the following raw materials in parts by mass:

50.7 parts of fused magnesite with the grain diameter of 0.045-0.074mm, 15 parts of alumina micropowder with the grain diameter of 1-3 mu m, 5 parts of chromium oxide fine powder with the grain diameter of 0.045-0.074mm, 4 parts of zirconium oxide fine powder with the grain diameter of 0.045-0.074mm, 4 parts of silicon carbide fine powder with the grain diameter of 0.045-0.074mm, 0.5 part of boron carbide fine powder with the grain diameter of 0.045-0.074mm, 0.3 part of sodium tripolyphosphate serving as a dispersant and 0.5 part of calcium lignosulfonate serving as a tackifier.

The content of MgO in the fused magnesia is more than 98wt%, the content of CaO is less than 1.5wt%, and Fe₂O₃Less than 0.5 wt%; al in alumina micropowder₂O₃Is greater than 99 wt%; cr in chromium oxide fine powder₂O₃Is greater than 99 wt%; ZrO in zirconia fine powder₂Is greater than 95 wt%; the SiC content in the silicon carbide fine powder is more than 97 wt%; b in fine boron carbide powder₄The content of C is more than 95 wt%.

The preparation method of the ladle erosion-resistant magnesia refractory mortar comprises the following steps:

according to the selected mass portions, mixing the preparation raw materials of the ladle anti-erosion magnesium refractory slurry, adding the mixture into a stirrer to stir for 3 minutes to obtain a uniform mixture, then adding water accounting for 35 percent of the total weight of the mixture into the mixture, and continuing stirring for 5 minutes until the mixture becomes uniform slurry, thus obtaining the ladle anti-erosion magnesium refractory slurry.

The ladle anti-erosion magnesia refractory mortar is used when a VOD ladle is built, the difference between the residual thickness of a brick joint and the residual thickness of a magnesia carbon brick after the ladle is offline is 21mm, a small amount of steel is clamped in the brick joint of the ladle brick, the residual thickness of the brick joint is lower, the addition amount of fused magnesia is too low, the addition amount of alumina micropowder is higher, and the slag erosion resistance effect of the refractory mortar is general.

Example 9

The ladle anti-erosion magnesia refractory mortar is prepared from the following raw materials in parts by mass:

69.3 parts of fused magnesite with the grain diameter of 0.045-0.074mm, 2 parts of alumina micropowder with the grain diameter of 1-3 mu m, 8 parts of chromium oxide fine powder with the grain diameter of 0.045-0.074mm, 8 parts of zirconium oxide fine powder with the grain diameter of 0.045-0.074mm, 8 parts of silicon carbide fine powder with the grain diameter of 0.045-0.074mm, 4 parts of boron carbide fine powder with the grain diameter of 0.045-0.074mm, 0.2 part of sodium tripolyphosphate serving as a dispersant and 0.5 part of calcium lignosulfonate serving as a tackifier.

The content of MgO in the fused magnesia is more than 98wt%, the content of CaO is less than 1.5wt%, and Fe₂O₃Less than 0.5 wt%; al in alumina micropowder₂O₃Is greater than 99 wt%; cr in chromium oxide fine powder₂O₃Is greater than 99 wt%; ZrO in zirconia fine powder₂Is greater than 95 wt%; the SiC content in the silicon carbide fine powder is more than 97 wt%; b in fine boron carbide powder₄The content of C is more than 95 wt%.

The preparation method of the ladle erosion-resistant magnesia refractory mortar comprises the following steps:

according to the selected mass portions, mixing the preparation raw materials of the ladle anti-erosion magnesium refractory slurry, adding the mixture into a stirrer to stir for 3 minutes to obtain a uniform mixture, then adding water accounting for 35 percent of the total weight of the mixture into the mixture, and continuing stirring for 5 minutes until the mixture becomes uniform slurry, thus obtaining the ladle anti-erosion magnesium refractory slurry.

The ladle anti-erosion magnesia refractory mortar is used when a VOD ladle is built, the difference between the residual thickness of a brick joint and the residual thickness of a magnesia carbon brick is 18mm after the ladle is offline, a small amount of steel is clamped in the brick joint of the ladle brick, and the refractory mortar has large expansion, more molten steel permeation and general use effect due to large addition amount of chromium oxide, zirconium oxide and silicon carbide.

Comparative example 1

The ladle refractory mortar of the comparative example is prepared from the following raw materials in parts by mass:

90 parts of fused magnesia with the grain diameter of 0.045-0.074mm, 5.3 parts of chromium oxide fine powder with the grain diameter of 0.045-0.074mm, 3 parts of silicon carbide fine powder with the grain diameter of 0.045-0.074mm, 0.5 part of boron carbide fine powder with the grain diameter of 0.045-0.074mm, 0.2 part of dispersant sodium tripolyphosphate, 0.5 part of tackifier calcium lignosulfonate and 0.5 part of tackifier carboxymethylcellulose sodium.

The preparation method of the ladle erosion-resistant magnesia refractory mortar in the comparative example comprises the following steps:

mixing the preparation raw materials according to the selected parts by weight, adding the mixture into a stirrer to stir for 3 minutes to obtain a uniform mixture, then adding water accounting for 35 percent of the total weight of the mixture into the mixture, and continuing stirring for 5 minutes until the mixture becomes uniform slurry to obtain the ladle refractory slurry.

The slurry is used when a VOD steel ladle is built, the difference between the residual thickness of a brick joint and the residual thickness of a magnesia carbon brick is 26mm after the steel ladle is offline, a large amount of steel is clamped in the brick joint of the steel ladle brick, and when alumina micro powder and zirconia fine powder are not added in the scheme, the shrinkage of the slurry is large, and the steel clamping in the brick joint is obvious. The scheme cannot meet the use requirement of the VOD ladle.

Comparative example 2

The ladle refractory mortar of the comparative example is prepared from the following raw materials in parts by mass:

82.8 parts of fused magnesite with the grain diameter of 0.045-0.074mm, 8 parts of alumina micropowder with the grain diameter of 1-3 mu m, 4 parts of chromium oxide fine powder with the grain diameter of 0.045-0.074mm, 4 parts of zirconium oxide fine powder with the grain diameter of 0.045-0.074mm, 0.2 part of dispersant sodium tripolyphosphate, 0.8 part of tackifier calcium lignosulfonate and 0.2 part of tackifier carboxymethylcellulose sodium.

The preparation method of the ladle erosion-resistant magnesia refractory mortar in the comparative example comprises the following steps:

mixing the preparation raw materials according to the selected parts by weight, adding the mixture into a stirrer to stir for 3 minutes to obtain a uniform mixture, then adding water accounting for 35 percent of the total weight of the mixture into the mixture, and continuing stirring for 5 minutes until the mixture becomes uniform slurry to obtain the ladle refractory slurry.

The slurry is used when the VOD steel ladle is built, the difference between the residual thickness of the brick joint and the residual thickness of the magnesia carbon brick is 28mm after the steel ladle is offline, a large amount of steel is clamped in the brick joint of the steel ladle brick, silicon carbide fine powder and boron carbide fine powder are not added in the scheme, the combination part of the slurry and the magnesia carbon brick is easy to oxidize, and the erosion performance of the magnesia carbon brick after oxidation is reduced. The scheme cannot meet the use requirement of the VOD ladle.

Comparative example 3

The preparation method of the ladle refractory mortar of the comparative example is the same as that of the example 1 in terms of the mass parts of the rest components of the preparation raw materials, and the difference is that 40 parts of alumina micropowder with the particle size of 1-3 mu m.

The slurry is used in the building of VOD steel ladles, the difference between the residual thickness of brick joints and the residual thickness of magnesia carbon bricks is 30mm after the steel ladles are off-line, a large amount of steel is clamped in the brick joints of the steel ladles, the addition amount of alumina micropowder is high, and the erosion resistance of the slurry is reduced. The scheme cannot meet the use requirement of the VOD ladle.

Comparative example 4

The ladle anti-erosion magnesia refractory mortar is prepared from the following raw materials in parts by mass:

40 parts of fused magnesia with the grain diameter of 0.045-0.074mm, 20 parts of alumina micro powder with the grain diameter of 1-3 mu m, 10 parts of chromium oxide fine powder with the grain diameter of 0.045-0.074mm, 10 parts of zirconia fine powder with the grain diameter of 0.045-0.074mm, 10 parts of silicon carbide fine powder with the grain diameter of 0.045-0.074mm, 8.8 parts of boron carbide fine powder with the grain diameter of 0.045-0.074mm, 0.2 part of dispersant sodium tripolyphosphate, 0.5 part of tackifier calcium lignosulfonate and 0.5 part of tackifier carboxymethylcellulose sodium.

The content of MgO in the fused magnesia is more than 98wt%, the content of CaO is less than 1.5wt%, and Fe₂O₃Less than 0.5 wt%; al in alumina micropowder₂O₃Is greater than 99 wt%; cr in chromium oxide fine powder₂O₃Is greater than 99 wt%; ZrO in zirconia fine powder₂Is greater than 95 wt%; the SiC content in the silicon carbide fine powder is more than 97 wt%; b in fine boron carbide powder₄The content of C is more than 95 wt%.

The preparation method of the ladle erosion-resistant magnesia refractory mortar comprises the following steps:

according to the selected mass portions, mixing the preparation raw materials of the ladle anti-erosion magnesium refractory slurry, adding the mixture into a stirrer to stir for 3 minutes to obtain a uniform mixture, then adding water accounting for 35 percent of the total weight of the mixture into the mixture, and continuing stirring for 5 minutes until the mixture becomes uniform slurry, thus obtaining the ladle anti-erosion magnesium refractory slurry.

The slurry is used in building VOD steel ladles, the difference between the residual thickness of brick joints and the residual thickness of magnesia carbon bricks is 32mm after the steel ladles are offline, a large amount of steel is clamped in the brick joints of the steel ladles, the addition amount of auxiliary materials is high, the erosion performance of the slurry is reduced, and the expansion is overlarge. The scheme cannot meet the use requirement of the VOD ladle.

It should be understood that the above examples are only for clarity of illustration and are not intended to limit the embodiments. Other variations and modifications will be apparent to persons skilled in the art in light of the above description. And are neither required nor exhaustive of all embodiments. And obvious variations or modifications therefrom are within the scope of the invention.