阅读说明：本技术 一种耐高温材料及其制备方法和中间包冲击区组合预制件及中间包冲击区 (High-temperature-resistant material and preparation method thereof, tundish impact area combined prefabricated part and tundish impact area ) 是由 张文国 李乃动 王炎平 孟凡祥 张学敏 梁绪正 孙晓 于 2019-12-04 设计创作，主要内容包括：本发明涉及高温材料技术领域,具体涉及一种耐高温材料及其制备方法和中间包冲击区组合预制件及中间包冲击区。本发明提供的耐高温材料,包括以下重量份数的制备原料：镁砂10～50份,铝矾土熟料30～75份,白刚玉粉2～10份,二氧化硅粉1～10份,钢纤维1～10份,减水剂0.1～1份,防爆纤维0.1～1份,水2～10份。本发明提供的耐高温材料有良好的热振稳定性、较强的抗冲击能力和优异的耐钢渣侵蚀性能,使用该高温材料制备的冲击区组合预制件及其配套的中间包冲击区,能够显著提高中间包的使用寿命。(The invention relates to the technical field of high-temperature materials, in particular to a high-temperature-resistant material and a preparation method thereof, a tundish impact area combined prefabricated member and a tundish impact area. The high-temperature resistant material provided by the invention comprises the following preparation raw materials in parts by weight: 10-50 parts of magnesia, 30-75 parts of bauxite chamotte, 2-10 parts of white corundum powder, 1-10 parts of silicon dioxide powder, 1-10 parts of steel fiber, 0.1-1 part of water reducing agent, 0.1-1 part of explosion-proof fiber and 2-10 parts of water. The high-temperature resistant material provided by the invention has good thermal vibration stability, stronger impact resistance and excellent steel slag corrosion resistance, and the impact area combined prefabricated part prepared by using the high-temperature material and the matched tundish impact area thereof can obviously prolong the service life of the tundish.)

1. The high-temperature-resistant material is characterized by comprising the following preparation raw materials in parts by weight:

10-50 parts of magnesia, 30-75 parts of bauxite chamotte, 2-10 parts of white corundum powder, 1-10 parts of silicon dioxide powder, 1-10 parts of steel fiber, 0.1-1 part of water reducing agent, 0.1-1 part of explosion-proof fiber and 2-10 parts of water.

2. The high-temperature resistant material according to claim 1, wherein the magnesite is one or more of 95 medium magnesite, 95 skin sand and 96 electric fused magnesite.

3. The refractory according to claim 1, wherein the bauxite clinker is one or more of 85 bauxite clinker, 88 bauxite clinker and brown alumina.

4. The high-temperature-resistant material according to claim 1, wherein the white corundum powder has a particle size of 180 to 200 meshes.

5. The refractory according to claim 1, wherein the silica powder has a particle size of < 1 μm.

6. The high-temperature-resistant material as recited in claim 1, wherein the water reducing agent is sodium hexametaphosphate and/or sodium tripolyphosphate.

7. The high temperature resistant material of claim 1 wherein the explosion proof fibers are filamentous polypropylene.

8. The method for preparing the high-temperature resistant material as claimed in any one of claims 1 to 7, which is characterized by comprising the following steps:

mixing magnesia, bauxite clinker, white corundum powder, silicon dioxide powder, steel fiber, a water reducing agent and explosion-proof fiber to obtain dry mixture;

and mixing the dry mixture with water, and sequentially carrying out forming, maintenance and baking to obtain the high-temperature-resistant material.

9. A tundish impact zone composite preform is characterized in that: comprises an integrally formed magnesia carbon brick, a bottom plate part, a baffle plate part and a buffer part; the bottom plate part, the baffle plate part and the buffer part are made of the high-temperature resistant material according to any one of claims 1 to 7 or the high-temperature resistant material prepared by the preparation method according to claim 8;

the bottom plate set up in the baffle with the bottom of buffering portion, the bottom plate the baffle with buffering portion constitutes an upper end open-ended cushion chamber, the outer bottom surface of bottom plate is equipped with a recess, the magnesia carbon brick is located in the recess of bottom plate, the bottom surface of magnesia carbon brick with the outer bottom surface parallel and level of bottom plate, the up end of buffering portion is equipped with the buffering recess, highly being greater than of buffering portion the height of baffle.

10. A tundish impact zone comprising a dry charge working layer and the tundish impact zone composite preform of claim 9, the dry charge working layer being located outside the floor portion and the cushioning portion.

Technical Field

The invention relates to the technical field of materials for continuous casting, in particular to a high-temperature-resistant material and a preparation method thereof, and a tundish impact area combined prefabricated member and a tundish impact area.

Background

Continuous casting is an important link of steelmaking production, and is the basis and guarantee for realizing efficient and low-cost production of the whole steelmaking system. The tundish is used as an important functional container for receiving molten steel, shunting the molten steel, promoting impurities in the molten steel to float and the like in the continuous casting production process, the requirement on the long-service-life safe and stable operation of the tundish in the continuous casting production process is higher and higher, and the importance of a tundish impact area as a key part for limiting the whole service life of the tundish is self-evident.

The currently common tundish impact area combination forms are as follows: dry material, an impact plate and a slag wall; dry material, a current stabilizer and a slag wall; dry material, an impact plate, a current stabilizer and a slag wall; dry material, an impact plate, a current stabilizer, a split guard plate and a slag stopping wall. However, the impact areas of the conventional tundish have the problems that the combined gaps of the split prefabricated parts are easy to seep steel and cannot resist molten steel scouring and steel slag corrosion, so that the service life of the whole tundish is short.

Disclosure of Invention

The invention aims to provide a more excellent high-temperature-resistant material and an advanced process for integral pre-forming, the high-temperature-resistant material provided by the invention has excellent thermal stability and more stable chemical properties, and a tundish impact zone combined prefabricated part manufactured by taking the high-temperature-resistant material provided by the invention as an original piece has excellent high-temperature resistance, impact resistance and steel slag corrosion resistance, and can obviously prolong the service life of a tundish.

In order to achieve the above object, the present invention provides the following technical solutions:

the invention provides a high-temperature-resistant material which comprises the following preparation raw materials in parts by weight:

10-50 parts of magnesia, 30-75 parts of bauxite chamotte, 2-10 parts of white corundum powder, 1-10 parts of silicon dioxide powder, 1-10 parts of steel fiber, 0.1-1 part of water reducing agent, 0.1-1 part of explosion-proof fiber and 2-10 parts of water.

Preferably, the magnesite is one or more of 95 medium magnesite, 95 skin sand and 96 electric smelting magnesite.

Preferably, the bauxite chamotte is one or more of 85 bauxite chamotte, 88 bauxite chamotte and brown aluminium oxide.

Preferably, the particle size of the white corundum powder is 180-200 meshes.

Preferably, the particle size of the silicon dioxide powder is < 1 μm.

Preferably, the water reducing agent is sodium hexametaphosphate and/or sodium tripolyphosphate.

Preferably, the explosion-proof fibers are filamentous polypropylene.

The invention provides a preparation method of the high-temperature resistant material in the technical scheme, which comprises the following steps:

mixing magnesia, bauxite clinker, white corundum powder, silicon dioxide powder, steel fiber, a water reducing agent and explosion-proof fiber to obtain dry mixture;

and mixing the dry mixture with water, and sequentially carrying out forming, maintenance and baking to obtain the high-temperature-resistant material.

The invention also provides a tundish impact area combined prefabricated part, which comprises the integrally formed magnesia carbon brick, a bottom plate part, a baffle plate part and a buffer part; the bottom plate part, the baffle plate part and the buffer part are made of the high-temperature-resistant material or the high-temperature-resistant material prepared by the preparation method in the technical scheme;

the bottom plate set up in the baffle with the bottom of buffering portion, the bottom plate the baffle with buffering portion constitutes an upper end open-ended cushion chamber, the outer bottom surface of bottom plate is equipped with a recess, the magnesia carbon brick is located in the recess of bottom plate, the bottom surface of magnesia carbon brick with the outer bottom surface parallel and level of bottom plate, the up end of buffering portion is equipped with the buffering recess, highly being greater than of buffering portion the height of baffle.

The invention also provides a tundish impact area, which comprises a dry material working layer and the tundish impact area combined prefabricated part in the technical scheme, wherein the dry material working layer is positioned at the outer sides of the bottom plate part and the buffer part.

The invention provides a high-temperature-resistant material which comprises the following preparation raw materials in parts by weight: 10-50 parts of magnesia, 30-75 parts of bauxite chamotte, 2-10 parts of white corundum powder, 1-10 parts of silicon dioxide powder, 1-10 parts of steel fiber, 0.1-1 part of water reducing agent, 0.1-1 part of explosion-proof fiber and 2-10 parts of water. In the invention, magnesia and bauxite chamotte are used as aggregates to play a role of a skeleton, oxygen in magnesium oxide and aluminum oxide forms an oxygen lattice under a high-temperature state, and magnesium ions and aluminum ions are mutually diffused to generate magnesium aluminate spinel; magnesium aluminate spinel (MgO. Al)₂O₃) The high-melting-point high-temperature-resistant high-temperature; the white corundum powder and the silicon dioxide powder can fill gaps among refractory aggregates and play a good role of a bonding agent; the steel fiber can effectively limit the expansion of the crack under the action of external force, and bears the stress together with the aggregate, so that the strength of the material is increased; the sodium hexametaphosphate has the functions of reducing water and plasticizing, so that the strength of the material can be improved while the water adding amount is reduced; the addition of the explosion-proof fiber can increase the water drainage effect of the material in the subsequent baking process and prevent the cracks generated by the water which cannot be removed in the baking process. The high-temperature resistant material provided by the invention has good thermal vibration stability, stronger impact resistance, excellent steel slag corrosion resistance, higher normal-temperature pressure resistance, higher breaking strength, high-temperature pressure resistance, higher breaking strength and lower re-burning line change rate; tundish impact area combined prefabricated part made of high-temperature-resistant material provided by the invention as original partThe service life of the tundish can be obviously prolonged.

Drawings

FIG. 1 is an elevation view of a tundish impact zone preform assembly provided by the present invention;

FIG. 2 is a top plan view of the tundish impact zone preform of FIG. 1;

FIG. 3 is a left cross-sectional view of the tundish impact zone preform assembly of FIG. 1;

in the figure, 1-middle part, 2-side part, 3-baffle part, 4-arc groove, 5-magnesia carbon brick, 6-bottom plate part and 7-buffer part.

Detailed Description

The invention provides a high-temperature-resistant material which comprises the following preparation raw materials in parts by weight:

10-50 parts of magnesia, 30-75 parts of bauxite chamotte, 2-10 parts of white corundum powder, 1-10 parts of silicon dioxide powder, 1-10 parts of steel fiber, 0.1-1 part of water reducing agent, 0.1-1 part of explosion-proof fiber and 2-10 parts of water.

The high-temperature-resistant material comprises 10-50 parts by weight of magnesia, preferably 20-50 parts by weight. In the invention, the magnesite is preferably one or more of 95 medium magnesite, 95 skin magnesite and 96 electric smelting magnesite.

Based on the weight parts of the magnesite, the preparation raw material of the high-temperature resistant material provided by the invention comprises 30-75 parts of bauxite clinker, preferably 35-70 parts. In the invention, the bauxite chamotte is preferably one or more of 85 bauxite chamotte, 88 bauxite chamotte and brown alumina.

Based on the weight parts of the magnesite, the preparation raw material of the high-temperature resistant material provided by the invention comprises 2-10 parts of white corundum powder, and preferably 3-9 parts. In the invention, the white corundum powder is preferably white corundum micro powder; the particle size of the white corundum powder is preferably 180-200 meshes, and more preferably 200 meshes.

Based on the weight parts of the magnesite, the preparation raw material of the high-temperature resistant material provided by the invention comprises 1-10 parts of silicon dioxide powder, preferably 2-9 parts. In the present invention, the silica powder is preferably a fine silica powder; the particle size of the silicon dioxide powder is preferably < 1 μm.

Based on the weight parts of the magnesite, the preparation raw material of the high-temperature resistant material provided by the invention comprises 1-10 parts of steel fiber, and preferably 1-9 parts. In the present invention, the steel fiber is preferably 446# heat resistant steel fiber.

Based on the weight parts of the magnesite, the preparation raw material of the high-temperature resistant material provided by the invention comprises 0.1-1 part of water reducing agent, preferably 0.2-0.9 part. In the invention, the water reducing agent is preferably sodium hexametaphosphate and/or sodium tripolyphosphate.

Based on the weight parts of the magnesite, the preparation raw materials of the high-temperature resistant material provided by the invention comprise 0.1-1 part of explosion-proof fiber, and preferably 0.1-0.9 part. In the present invention, the explosion-proof fiber is preferably filamentous polypropylene, and more preferably white filamentous polypropylene. In the invention, the explosion-proof fiber has better hydrophobic and air-exhausting functions, and can prevent the material from cracking and bursting.

Based on the weight parts of the magnesite, the preparation raw material of the high-temperature-resistant material provided by the invention comprises 2-10 parts of water, and preferably 3-9 parts of water.

The invention provides a preparation method of the high-temperature resistant material in the technical scheme, which comprises the following steps:

mixing magnesia, bauxite clinker, white corundum powder, silicon dioxide powder, steel fiber, a water reducing agent and explosion-proof fiber to obtain dry mixture;

and mixing the dry mixture with water, and sequentially carrying out forming, maintenance and baking to obtain the high-temperature-resistant material.

The dry mixture is obtained by mixing magnesia, bauxite chamotte, white corundum powder, silicon dioxide powder, steel fiber, a water reducing agent and explosion-proof fiber. In the invention, the raw material adding sequence principle during the mixing is preferably that the raw materials are sequentially added according to the particle size from large to small, then the steel fiber is slowly added, the explosion-proof fiber is slowly added after the mixture is stirred for a period of time, and the mixture is stirred until the steel fiber and the explosion-proof fiber are completely dispersed to obtain a first mixture; then mixing the first mixture with fine powder of magnesite and bauxite clinker to obtain a second mixture; mixing the second mixture with white corundum powder and silicon dioxide powder to obtain a third mixture; and finally, mixing the third mixture with a water reducing agent to obtain a dry mixture. The stirring speed of the mixing is not particularly limited in the present invention, and a stirring speed known in the art may be used. In the invention, the mixing time of the dry mixture is preferably 2min, and the timing is started after the magnesite, the bauxite chamotte, the white corundum powder, the silicon dioxide powder, the steel fiber, the water reducing agent and the explosion-proof fiber are all added.

After the dry mixture is obtained, the dry mixture is mixed with water, and the high-temperature-resistant material is obtained through molding, curing and baking in sequence. According to the invention, the dry mixture is mixed with water to obtain the pug. In the invention, the mixing time of the dry mixture and water is preferably 6-10 min.

In the present invention, the molding time is preferably less than 40min to ensure the fluidity of the pug. In the invention, the forming is preferably vibration forming, and the specific process method is preferably as follows: adding the pug into a combined die fixed on a vibration platform, controlling the forming time by using a timing meter, realizing the product shaping by depending on the vibration of the die and a workbench, and always opening the vibration platform when the pug is added and fixed in the die on the vibration platform so as to ensure the compactness of the pug and the sufficient discharge of gas in the die.

According to the invention, after the forming is finished, the upper surface of the material forming is preferably flapped to the return paddle by using a mud plate and flattened so as to ensure the flatness of the forming surface.

In the invention, the environment temperature for curing is preferably not less than 40 ℃, and more preferably 40-60 ℃; the humidity of the environment for maintenance is preferably less than or equal to 50%, and more preferably 20-50%. In the invention, the curing time is preferably 36h, wherein the curing is carried out with a mold for the first 24h, and the curing is carried out for 12h after demolding.

In the invention, the baking time is preferably 25-30 h, more preferably 29h, and the moisture in the material can be fully discharged to be dry.

In the invention, the baking is preferably gradient baking, and comprises a first temperature rise stage, a first heat preservation stage, a second temperature rise stage, a second heat preservation stage, a third temperature rise stage, a fourth temperature rise stage and a fourth heat preservation stage which are sequentially carried out. In the invention, the first temperature rise stage is preferably raised from 20 ℃ to 70 ℃, and the temperature rise rate of the first temperature rise stage is preferably 16.6 ℃/h; the temperature of the first heat preservation stage is preferably 70 ℃, and the heat preservation time of the first heat preservation stage is preferably 3 hours; the temperature of the second temperature rise stage is preferably raised from 70 ℃ to 150 ℃, and the temperature rise rate of the second temperature rise stage is preferably 10 ℃/h; the temperature of the second heat preservation stage is preferably 150 ℃, and the heat preservation time of the second heat preservation stage is preferably 2 hours; the temperature of the third temperature rise stage is preferably raised from 150 ℃ to 180 ℃, and the temperature rise rate of the third temperature rise stage is preferably 10 ℃/h; the fourth temperature rise stage is preferably increased from 180 ℃ to 240 ℃, and the temperature rise rate of the fourth temperature rise stage is preferably 15 ℃/h; the temperature of the fourth heat preservation stage is preferably 240 ℃, and the heat preservation time of the fourth heat preservation stage is preferably 6 h. According to the invention, through the gradient baking, the moisture in the material can be discharged, and the crack generated in the material can be avoided.

The invention also provides a tundish impact area combined prefabricated part, which comprises the integrally formed magnesia carbon brick, a bottom plate part, a baffle plate part and a buffer part; the bottom plate part, the baffle plate part and the buffer part are made of the high-temperature-resistant material or the high-temperature-resistant material prepared by the preparation method in the technical scheme;

the bottom plate set up in the baffle with the bottom of buffering portion, the bottom plate the baffle with buffering portion constitutes an upper end open-ended cushion chamber, the outer bottom surface of bottom plate is equipped with a recess, the magnesia carbon brick is located in the recess of bottom plate, the bottom surface of magnesia carbon brick with the outer bottom surface parallel and level of bottom plate, the up end of buffering portion is equipped with the buffering recess, highly being greater than of buffering portion the height of baffle.

The tundish impact area combined prefabricated member provided by the invention is prepared by adopting the high-temperature-resistant material and the magnesia carbon brick in the technical scheme, and the bottom plate part, the baffle plate part and the buffer part are combined to form an integrally formed buffer cavity, so that the phenomenon of steel seepage in gaps of the combined part is reduced, the labor intensity of field construction is reduced, and the service life of the tundish impact area combined prefabricated member is prolonged.

In the present invention, the magnesia carbon brick preferably has a size of 500mm × 500mm × 100 mm. The magnesia carbon brick is positioned in the groove of the bottom plate part as a shaping product, so that the tundish impact area combined prefabricated part has more excellent molten steel impact resistance.

In the present invention, the buffer portion preferably includes a middle portion and two side portions, the two side portions are preferably located at both sides of the middle portion, the two side portions are preferably symmetrically disposed, and the heights of the middle portion and the two side portions are preferably the same. In the present invention, the side portions are preferably arc-shaped plates, and the baffle portion is preferably tangent to the arc-shaped edges of the two side portions. In the present invention, the buffer groove is preferably an arc-shaped groove.

As an embodiment of the invention, the tundish impact zone combined prefabricated member comprises a magnesia carbon brick 5, a bottom plate part 6, a baffle plate part 3 and a buffer part 7 which are integrally formed, wherein the bottom plate part 6 is arranged at the bottoms of the baffle plate part 3 and the buffer part 7, the bottom plate part 6, the baffle plate part 3 and the buffer part 7 form a buffer cavity with an upper end opened, a groove is arranged on the outer bottom surface of the bottom plate part 6, the magnesia carbon brick 5 is positioned in the groove of the bottom plate part 6, as shown in FIG. 3, the bottom surface of the magnesia carbon brick 5 is flush with the outer bottom surface of the bottom plate part, a buffer groove is arranged on the upper end surface of the buffer part 7, and the height of the buffer part 7 is greater than that of the baffle plate part 3.

According to the tundish impact area combined prefabricated member and the tundish impact area, in the specific application process, the magnesia carbon bricks 5 are arranged in the grooves of the bottom plate part 6, so that the impact resistance of the bottom plate part 6 is improved, the bottom of the tundish impact area combined prefabricated member is protected, the bottom plate part 6, the baffle plate part 3 and the buffer part 7 form the integrally formed buffer area, compared with the prefabricated member assembled by the conventional single mold, the phenomenon of steel seepage in gaps of the combined part is reduced, and the labor intensity of site construction is reduced due to the fact that the complicated construction process of site assembly of the split prefabricated member is omitted. The buffer zone integrally formed in the device has a function of inhibiting molten steel from splashing everywhere, the molten steel overflows from the baffle part 3 after being filled in the buffer zone, so that the flow of the molten steel is more smooth and does not splash everywhere, the molten steel is stably injected, the service life of the tundish impact zone is prolonged, and the upper end surface of the buffer part 7 is provided with a groove to play a role in facilitating slag discharge.

As a specific embodiment of the invention, the buffer part 7 comprises a middle part 1 and two side parts 2, the two side parts 2 are positioned at two sides of the middle part 1, the two side parts 2 are symmetrically arranged, and the heights of the middle part 1 and the two side parts 2 are the same, so that the joint with a tundish is ensured, and molten steel is prevented from splashing everywhere.

As an embodiment of the present invention, in order to be attached to the dry material working layer of the tundish, the side portions 2 are arc-shaped plates, and the baffle portions 3 are tangent to the arc-shaped edges of the two side portions 2.

As an embodiment of the present invention, in order to achieve smooth slag discharge, a groove 4 is provided, as shown in fig. 1.

The invention also provides a tundish impact area, which comprises a dry material working layer and the tundish impact area combined prefabricated part in the technical scheme, wherein the dry material working layer is positioned at the outer sides of the bottom plate part, the middle part and the two side parts. The specific composition of the dry material working layer is not particularly limited in the invention, and the dry material working layer can be prepared by using dry materials well known in the field. In one embodiment of the present invention, the dry material working layer is located outside the floor portion 6, the intermediate portion 1, and the two side portions 2, and it is necessary to lay dry material outside the floor portion 6, the intermediate portion 1, and the two side portions 2 during on-site construction.

The technical solution of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. It is to be understood that the described embodiments are merely exemplary of the invention, and not restrictive of the full scope of the invention. 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.