CN113387685A - High-calcium homogenized magnesia carbon brick and preparation method thereof - Google Patents
High-calcium homogenized magnesia carbon brick and preparation method thereof Download PDFInfo
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Abstract
The invention discloses a high-calcium homogenized magnesia carbon brick and a preparation method thereof, which are used for preparing high-calcium fused magnesia bricks. According to the mass parts, 800-900 parts of high-calcium fused magnesia, 10-80 parts of crystalline flake graphite, 30-40 parts of phenolic resin, 5-30 parts of antioxidant and 30-80 parts of additive, wherein the additive is a mixture of calcium monoaluminate with a chemical formula of CaO.Al2O3 and calcium dialuminate with a chemical formula of CaO.2Al2O3, and the granularity of the mixture is 0.5-0.045 mm. The preparation method adopts the following technical scheme: firstly, crushing fused magnesia, then sending the crushed fused magnesia into a closed material box, spraying water to wet, standing for 24 hours, then drying, and screening into three granularities for later use; premixing an additive and an antioxidant for later use; mixing the screened granularity material, phenolic resin, crystalline flake graphite and premix; pressing and forming into green bricks; drying is carried out. Solves the problems of low thermal shock stability, easy stripping at high temperature and easy hydration of the magnesia-calcium-carbon brick of the low-carbon brick.
Description
Technical Field
The invention relates to the technical field of refractory materials for iron and steel enterprises, in particular to a calcium-containing magnesia carbon brick and a preparation method thereof.
Background
The conventional refractory materials for producing steel ladles such as low-carbon steel, stainless steel and the like mainly adopt MgO-C bricks, namely magnesia carbon bricks, and along with the rapid development of smelting technologies of clean steel and ultra-low carbon steel, the low-carbon magnesia carbon bricks are adopted to reduce the carbon content in molten steel by reducing the graphite content of the magnesia carbon bricks. The low-carbon magnesia carbon brick is generally characterized in that the graphite content is reduced on the basis of a common magnesia carbon brick, the carbon content is controlled to be 4-8, and after the graphite content is reduced, the magnesia carbon brick is inevitably poor in thermal shock resistance and easy to strip in the using process, so that the service life of a ladle is reduced.
In order to improve the thermal shock resistance, the high-quality carbon-containing alkaline composite refractory MgO-CaO-C brick, namely a magnesia-calcium-carbon brick, developed in recent years is produced at present, the magnesia-calcium-carbon brick mainly takes high-purity sintered dolomite, synthetic magnesia dolomite and sintered CaO clinker, or high-purity fused dolomite, magnesia dolomite and fused CaO clinker and the like as main raw materials, and then is synthesized with flaky graphite and an anhydrous resin binder to produce a refractory product, wherein the MgO-CaO-C content is 60-70%, the CaO content is 10-20%, and the C content is about 8-15%. The MgO-CaO-C brick has the advantages of high thermal stability, strong erosion resistance of slag (especially low-alkalinity slag), excellent slag permeability, thermal shock resistance and thermal conductivity, molten steel purification and the like due to the existence of CaO in the composite refractory material. Therefore, the brick has the advantages of longer service life than MgO-C bricks under the conditions of high steelmaking temperature, long operation time, large slag change and the like, thereby having good use effect.
However, the raw materials adopted in the preparation process of the MgO-CaO-C brick are easy to absorb moisture and hydrate in the atmosphere due to the existence of free CaO to generate hydroxide, so that the strength of the product is reduced and even the product is collapsed. The hydration of calcium is difficult to avoid in the process of production, storage and transportation, thereby causing the problems of low yield, short storage time, incapability of using products and the like. In order to avoid hydration of the magnesia-calcium-carbon brick, the magnesia-calcium-carbon brick needs to be subjected to measures such as wax dipping or vacuum packaging, so that the production cost is high, and the hydration problem cannot be thoroughly solved in the whole processes of production, sale, storage and transportation.
Disclosure of Invention
The invention aims to provide a MgO-CaO-C brick which is low in carbon and high in calcium, can be uniformly distributed and has good hydration resistance and a preparation method thereof.
The technical scheme adopted by the high-calcium homogenized magnesia carbon brick is as follows: according to the mass portion, 800-900 portions of high calcium fused magnesia, 10-80 portions of crystalline flake graphite, 30-40 portions of phenolic resin, 5-30 portions of antioxidant and 30-80 portions of additive, wherein the additive is CaO and Al in the chemical formula2O3Calcium monoaluminate and CaO.2Al of the formula2O3Of calcium dialuminate, the particle size of said mixture being in the range of 0.5 to 0.045 mm.
In a preferred embodiment of the high calcium homogenized magnesia carbon brick of the present invention, said CaO, Al2O3With CaO.2Al2O3The mixing ratio of the mixture is 1-1.5: 1.
in a preferred embodiment of the high-calcium homogenized magnesia carbon brick, the high-calcium fused magnesia contains 95-97 wt% of MgO and 2-4 wt% of CaO.
Furthermore, in the total mass parts of the high-calcium fused magnesia, the particle size is 14-17% for 5-3mm, 34-37% for 3-1mm and 46-49% for 1-0.088 mm.
In a preferred embodiment of the high-calcium homogenized magnesia carbon brick, the weight percentage of C in the flaky graphite is 95-99%.
In a preferred embodiment of the high calcium homogenized magnesia carbon brick of the present invention, the phenolic resin is a conventional thermosetting phenolic resin.
In a preferred embodiment of the high calcium homogenized magnesia carbon brick of the invention, the antioxidant is one or a mixture of two of Si, silicon nitride or AL-O-N.
Further, the particle size of the antioxidant is D50=1-2 μm.
The preparation method of the high-calcium homogenized magnesia carbon brick adopts the following technical scheme: the method comprises the following steps:
step A: firstly, crushing fused magnesia into a material with the granularity of 5-0.088mm, sending the material into a closed material box, spraying water to wet and standing for 24 hours to fully hydrate CaO on the surface of the material, then sending the material into a drying kiln to be heated to the temperature of 120 ℃ and 150 ℃, preserving the heat for 5-10 hours to dry, and screening the material into three granularities of 5-3mm,3-1mm and 1-0.088mm for later use;
and B: fully premixing the additive and the antioxidant by using a premixer for later use;
and step C, proportionally placing the screened high-calcium fused magnesia granularity materials with the granularity of 5-3mm,3-1mm and 1-0.088mm into a mixing roll to mix for 3-8 minutes, then adding phenolic resin to mix for 3-5 minutes, then adding graphite to mix for 3-5 minutes, and finally adding the additive and the antioxidant premix to mix for 20-40 minutes.
D, putting the mixed pug into a mould, and pressing and forming the pug into a green brick according to a preset size;
step E, drying the green bricks: and (3) putting the green bricks subjected to compression molding into a drying kiln for drying, wherein the drying temperature is 200 ℃ and 250 ℃, and the drying time is 12-16 hours.
In a preferred embodiment of the method for preparing the high-calcium homogenized magnesia carbon brick of the invention, the mixer for mixing and kneading the materials in the step C is a circulating high-speed mixer, and the drying kiln in the step E is a tunnel type drying kiln.
The invention has the following beneficial effects: on one hand, high-calcium fused magnesite which is generally formed by sintering non-artificially synthesized ores and has uniform CaO distribution and more stable quality is selected, and on the other hand, a novel calcium oxide additive is introduced and added in a small-granularity and fine-divided form to realize the homogenization of calcium; and the low carbonization of graphite in the brick can be realized in the material preparation and the process, and the problem of carbon pollution of low-carbon steel can be reduced. The thermal shock stability of the brick is greatly improved, and the brick has certain performance of the magnesia-calcium-carbon brick due to the existence of calcium, does not need waterproof vacuum-pumping packaging, has long storage time, wide market prospect and development value.
1. And (4) selecting a main raw material. High-calcium fused magnesia is selected as a main raw material, and in the total mass part of the high-calcium fused magnesia, the high-calcium fused magnesia comprises 14-17% of high-calcium fused magnesia with the granularity of 5-3mm, 34-37% of high-calcium fused magnesia with the granularity of 3-1mm, and 46-49% of high-calcium fused magnesia with the granularity of 1-0.088 mm. And the fused sand is subjected to calcium hydration treatment before use, and the adoption of the magnesia reduces the components of free calcium, avoids the hydration of calcium oxide in the production process and ensures the homogenization of calcium in the magnesia carbon brick.
2. And (4) selecting an additive. Calcium is introduced and uniformly differentiated into the refractory material by artificially synthesizing the additive, so that a certain amount of calcium is contained in the brick, and the hydration resistance of the calcium can be ensured. In addition, under the high-temperature and high-slag state, a high-viscosity slag layer can be generated on the surface of the high-calcium homogenized magnesia carbon brick, the penetration of slag is inhibited, and the non-wettability of slag similar to graphite is formed, so that the adding amount of graphite is reduced; the deterioration and damage of materials are reduced, and meanwhile, the aluminum killed (alkaline) slag and the silicon killed (acidic) slag are compatible to be treated, and the slag penetration resistance is improved; the densification of a hot end substrate can be promoted, a through hole channel is blocked, and the oxidation resistance is effectively improved, so that the using amount of an antioxidant is reduced, and the economic benefit is improved; improve the overall erosion/scouring resistance; flexible (shaping) particles are generated in the brick at high temperature, so that the internal stress is relieved, and the stress damage is reduced. Thereby improving the thermal vibration stability of the magnesia carbon brick. The thermal stress is relieved, and the thermal shock damage is reduced;
the invention has the advantages of the low-carbon brick, solves the problems of low thermal shock stability and easy stripping at high temperature of the low-carbon brick, also has the excellent performance of the magnesia-calcium-carbon brick, and solves the problem of easy hydration of the magnesia-calcium-carbon brick.
Drawings
FIG. 1 shows the effect of hydration resting time on the degree of hydration;
FIG. 2 shows the effect of hydration resting time on compressive strength.
Detailed Description
The technical solutions in the embodiments of the present invention will be described clearly and completely with reference to the following embodiments of the present invention, and it is obvious 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.
The high-calcium homogenized magnesia carbon brick provided by the invention has the selected high-calcium fused magnesia with the mass percentage of 95-97 percent of MgO, 2-4 percent of CaO and high-calcium fused magnesiaAfter the granularity of the magnesite is passed, three granularities of 5-3mm,3-1mm and 1-0.088mm are selected, wherein the three granularities are 14-17% of 5-3mm, 34-37% of 3-1mm and 46-49% of 1-0.088mm in the total mass part of the high-calcium fused magnesite, and the magnesite with different granularities is mixed according to the proportion, so that a better homogenization effect can be achieved. The mass percentage of C in the crystalline flake graphite is 95-99%. The phenolic resin is generally common thermosetting phenolic resin. The antioxidant is Si, silicon nitride or AL-O-N, one or a mixture of more than two of the above can be selected, and the particle size of the antioxidant is D50=1-2 mu m. The additive is calcium aluminate (chemical formula is CaO. Al)2O3) With calcium dialuminate (chemical formula CaO.2 Al)2O3) Said CaO, Al2O3With CaO.2Al2O3The mixing ratio of the mixture may be 1 to 1.5: 1, the particle size of the additive mixture is controlled within the range of 0.5 to 0.045mm, which has a very favourable effect on the properties of the green article.
The preparation method of the high-calcium homogenized magnesia carbon brick provided by the invention comprises the steps of firstly crushing fused magnesia into a material with the granularity of 5-0.088mm, feeding the material into a closed material box, spraying water to wet and standing for 24 hours to fully hydrate CaO on the surface of the material, feeding the material into a drying kiln, heating to the temperature of 120 ℃ and 150 ℃, keeping the temperature for 5-10 hours to dry, screening the material into the granularity of 5-3mm,3-1mm and 1-0.088mm for later use, crushing the fused magnesia to hydrate, and screening the magnesia into three granularity materials, wherein the three granularity materials are important bases for improving the homogenization degree and hydration resistance of the magnesia; the particle size range of the additive mixture is controlled within 0.5-0.045mm, the additive and the antioxidant are fully premixed, and then the premixed material and other raw materials are mixed to enable the premixed material to be uniformly distributed in the mixed pug.
Example 1
Taking high-calcium fused magnesia, crystalline flake graphite, phenolic resin, an antioxidant and an additive in parts by mass, wherein:
800 parts of high-calcium fused magnesia, wherein in the total mass part, 14% of high-calcium fused magnesia has a granularity of 5-3mm, 37% of high-calcium fused magnesia has a granularity of 3-1mm, 49% of high-calcium fused magnesia has a granularity of 1-0.088mm, 95% of high-calcium fused magnesia has a mass percentage of MgO, and 2% of high-calcium fused magnesia has a mass percentage of CaO;
10 parts of flake graphite, wherein the mass percentage of flake graphite C is 95%;
30 parts of phenolic resin, wherein the phenolic resin is common thermosetting phenolic resin;
5 parts of antioxidant, wherein the antioxidant is Si, and the particle size is D50=1 mu m;
30 portions of additive, CaO and Al in the additive2O3With CaO.2Al2O3The mixing ratio of (1): 1, the particle size is 0.5 mm.
Crushing fused magnesia into a material with the granularity of 5-0.088mm, sending the material into a closed material box, spraying water to wet and standing for 24 hours, sending the material into a drying kiln, heating to 120 ℃, preserving heat for 5 hours, and screening into three granularities of 5-3mm,3-1mm and 1-0.088mm for later use;
fully premixing the additive and the antioxidant by a premixer to prepare premix;
putting the high-calcium fused magnesia particle size materials with three particle sizes of 5-3mm,3-1mm and 1-0.088mm into a circulating high-speed mixing mill in proportion for mixing for 3 minutes, then adding phenolic resin for mixing for 3 minutes, adding graphite for mixing for 3 minutes, and finally adding the additive and the antioxidant premix for mixing for 20 minutes;
putting the mixed pug into a mould, and pressing and forming the pug into a green brick according to a preset size;
and (3) putting the green bricks subjected to compression molding into a tunnel type drying kiln for drying at the drying temperature of 200 ℃ for 12 hours.
The high-calcium homogenized magnesia carbon brick prepared by the method has the following volume density, apparent porosity and compressive strength:
the bulk density is 3.08g/cm3(ii) a The apparent porosity is 3.05%; the compressive strength was 56.9 MPa.
FIG. 1 shows a comparative experiment conducted in example 1 in which the hydration and standing time was changed while keeping other parameters unchanged, and the influence of the hydration and standing time on the hydration resistance of the magnesite brick in the experiment was observed. Crushing high-calcium fused magnesia into a material with the granularity of 5-0.088mm, sending the material into a closed bin, wetting by spraying water, respectively selecting 2, 5, 10, 16, 20, 24 and 25 hours for hydration and standing, observing the particle size material hydrated and standing in the time period, and determining the pulverization quantity of particles in each square centimeter of the surface of the green brick produced by press forming so as to determine the hydration-resistant effect of the green brick, wherein the pulverization quantity is gradually reduced along with the increase of the hydration and standing time, and when the hydration and standing time exceeds 24 hours, the pulverization phenomenon cannot be basically seen on the surface of the green brick.
FIG. 2 shows the effect of hydration and standing time on the compressive strength of magnesite bricks, and it can be seen that the longer the hydration and standing time is, the more sufficient the hydration is, the higher the compressive strength of the green bricks is.
Example 2
Taking high-calcium fused magnesia, crystalline flake graphite, phenolic resin, an antioxidant and an additive in parts by mass, wherein:
850 parts of high-calcium fused magnesia, wherein in the total mass part, the high-calcium fused magnesia accounts for 16% of the total mass with the granularity of 5-3mm, 36% of the total mass with the granularity of 3-1mm, 48% of the total mass with the granularity of 1-0.088mm, 96% of the mass percentage of MgO and 3% of the mass percentage of CaO;
40 parts of flake graphite, wherein the mass percentage of flake graphite C is 97%;
30 parts of phenolic resin, wherein the phenolic resin is common thermosetting phenolic resin;
15 parts of antioxidant, wherein the antioxidant is silicon nitride, and the particle size is D50=1 mu m;
50 parts of additive, wherein CaO and Al are contained in the additive2O3With CaO.2Al2O3The mixing ratio of (1): 1.3, the particle size is 0.1 mm.
Crushing fused magnesia into a material with the granularity of 5-0.088mm, sending the material into a closed material box, spraying water to wet and standing for 24 hours, sending the material into a drying kiln, heating to 130 ℃, preserving heat for 7 hours, and screening into three granularities of 5-3mm,3-1mm and 1-0.088mm for later use;
fully premixing the additive and the antioxidant by a premixer to prepare premix;
putting the high-calcium fused magnesia particle size materials with three particle sizes of 5-3mm,3-1mm and 1-0.088mm into a circulating high-speed mixing mill in proportion for mixing for 5 minutes, then adding phenolic resin for mixing for 4 minutes, adding graphite for mixing for 4 minutes, and finally adding the additive and the antioxidant premix for mixing for 30 minutes;
putting the mixed pug into a mould, and pressing and forming the pug into a green brick according to a preset size;
and (3) putting the green bricks subjected to compression molding into a tunnel type drying kiln for drying at the drying temperature of 220 ℃ for 14 hours.
The high-calcium homogenized magnesia carbon brick prepared by the method has the following volume density, apparent porosity and compressive strength:
the bulk density is 3.09g/cm3(ii) a The apparent porosity is 3.06%; the compressive strength was 56.8 MPa.
Example 3
Taking high-calcium fused magnesia, crystalline flake graphite, phenolic resin, an antioxidant and an additive in parts by mass, wherein:
900 parts of high-calcium fused magnesia, wherein in the total mass part, 17% of high-calcium fused magnesia has the granularity of 5-3mm, 34% of high-calcium fused magnesia has the granularity of 3-1mm, 49% of high-calcium fused magnesia has the granularity of 1-0.088mm, 97% of MgO, and 4% of CaO;
80 parts of flake graphite, wherein the mass percentage of flake graphite C is 99%;
40 parts of phenolic resin, wherein the phenolic resin is common thermosetting phenolic resin;
30 parts of antioxidant, wherein the antioxidant is a mixture of Si, silicon nitride and AL-O-N, and the particle size is D50=2 mu m;
80 parts of additive, wherein CaO and Al are contained in the additive2O3With CaO.2Al2O3The mixing ratio of (1): 1.5, the particle size is 0.045 mm.
Crushing fused magnesia into a material with the granularity of 5-0.088mm, sending the material into a closed material box, spraying water to wet and standing for 24 hours, sending the material into a drying kiln, heating to 150 ℃, preserving heat for 10 hours, and screening into three granularities of 5-3mm,3-1mm and 1-0.088mm for later use;
fully premixing the additive and the antioxidant by a premixer to prepare premix;
putting the high-calcium fused magnesia particle size materials with three particle sizes of 5-3mm,3-1mm and 1-0.088mm into a circulating high-speed mixing mill in proportion for mixing for 8 minutes, then adding phenolic resin for mixing for 5 minutes, adding graphite for mixing for 5 minutes, and finally adding the additive and the antioxidant premix for mixing for 30 minutes;
putting the mixed pug into a mould, and pressing and forming the pug into a green brick according to a preset size;
and (3) putting the green bricks subjected to compression molding into a tunnel type drying kiln for drying at the drying temperature of 250 ℃ for 16 hours.
The high-calcium homogenized magnesia carbon brick prepared by the method has the following volume density, apparent porosity and compressive strength:
the bulk density is 3.1g/cm3(ii) a The apparent porosity is 3.06%; the compressive strength was 57.1 MPa.
The technical indexes of the high-calcium magnesia brick products of examples 1 to 3 of the invention are shown in the following table 1
Table 1: technical indexes of high-calcium magnesia carbon bricks
Comparative example 1
In example 1, the particle size of the additive was changed to 0.75-1mm, which is outside the range of 0.5-0.045mm, while the other component parameters were kept unchanged.
The high-calcium homogenized magnesia carbon brick prepared by the method has the following volume density, apparent porosity and compressive strength:
the bulk density is 2.91g/cm3(ii) a Apparent porosity is 4.01%; the compressive strength was 54.7 MPa.
Comparative example 2
In example 1, the particle size of the additive was changed to 0.35-0.01mm, which is outside the range of 0.5-0.045mm, while the other component parameters were kept unchanged.
The high-calcium homogenized magnesia carbon brick prepared by the method has the following volume density, apparent porosity and compressive strength:
the bulk density is 2.93g/cm3(ii) a Apparent porosity is 3.98%; the compressive strength was 55.2 MPa.
Table 2 shows that the particle size of the additive has influence on the volume density, the apparent porosity and the compressive strength of the green brick, the particle size of the additive in the range of 0.5-0.045mm can obtain better volume density, apparent porosity and compressive strength, and when the particle size of the additive is larger than 0.5mm or smaller than 0.045mm, the volume density, the apparent porosity and the compressive strength of the green brick are influenced by different degrees and are deteriorated.
Table 2: effect of additive particle size on Green brick Performance
It should be understood that any modification, equivalent replacement, improvement or the like made within the spirit and principle of the present invention should be considered to be included in the scope of protection of the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, it will be apparent to one skilled in the art that changes may be made in the embodiments and/or equivalents thereof without departing from the spirit and scope of the invention.
Claims (10)
1. The high-calcium homogenized magnesia carbon brick is characterized by comprising, by mass, 800-900 parts of high-calcium fused magnesia, 10-80 parts of crystalline flake graphite, 30-40 parts of phenolic resin, 5-30 parts of antioxidant and 30-80 parts of additive, wherein the additive is of a chemical formula CaO, Al2O3Calcium monoaluminate and CaO.2Al of the formula2O3Of calcium dialuminate, the particle size of said mixture being in the range of 0.5 to 0.045 mm.
2. The high calcium homogenized magnesia carbon brick as claimed in claim 1, wherein said CaO, Al2O3With CaO.2Al2O3The mixing ratio of the mixture is 1-1.5: 1.
3. the high-calcium homogenized magnesia carbon brick according to claim 1 or 2, characterized in that the high-calcium fused magnesia contains 95-97% by mass of MgO and 2-4% by mass of CaO.
4. The high-calcium homogenized magnesia carbon brick as claimed in claim 3, wherein the high-calcium fused magnesia sand comprises 14-17% of high-calcium fused magnesia sand with a particle size of 5-3mm, 34-37% of high-calcium fused magnesia sand with a particle size of 3-1mm, and 46-49% of high-calcium fused magnesia sand with a particle size of 1-0.088 mm.
5. The high-calcium homogenized magnesia carbon brick as claimed in claim 1, wherein the weight percentage of C in the flake graphite is 95-99%.
6. The high calcium homogenized magnesia carbon brick of claim 1, wherein said phenolic resin is a normal thermosetting phenolic resin.
7. The high calcium homogenized magnesia carbon brick of claim 1, wherein said antioxidant is one or a mixture of two of Si, silicon nitride or AL-O-N.
8. The high-calcium homogenized magnesia carbon brick according to claim 7, characterized in that the antioxidant has a particle size of D50=1-2 μm.
9. A method for preparing the high calcium homogenized magnesia carbon brick as claimed in any one of claims 1 to 8, characterized by comprising the following steps:
step A: firstly, crushing fused magnesia into a material with the granularity of 5-0.088mm, sending the material into a closed material box, spraying water to wet and standing for 24 hours to fully hydrate CaO on the surface of the material, then sending the material into a drying kiln to be heated to the temperature of 120 ℃ and 150 ℃, preserving the heat for 5-10 hours to dry, and screening the material into three granularities of 5-3mm,3-1mm and 1-0.088mm for later use;
and B: fully premixing the additive and the antioxidant by using a premixer for later use;
step C, proportionally placing the high-calcium fused magnesia granularity materials with the screened granularity of 5-3mm,3-1mm and 1-0.088mm into a mixing roll to mix for 3-8 minutes, then adding phenolic resin to mix for 3-5 minutes, then adding graphite to mix for 3-5 minutes, and finally adding the additive and the antioxidant premix to mix for 20-40 minutes;
d, putting the mixed pug into a mould, and pressing and forming the pug into a green brick according to a preset size;
step E, drying the green bricks: and (3) putting the green bricks subjected to compression molding into a drying kiln for drying, wherein the drying temperature is 200 ℃ and 250 ℃, and the drying time is 12-16 hours.
10. The method of claim 9, wherein the mixer for mixing the materials in step C is a circular high-speed mixer, and the drying kiln in step E is a tunnel type drying kiln.
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115321956A (en) * | 2022-08-19 | 2022-11-11 | 辽宁中镁控股股份有限公司 | High-temperature liquid phase toughened magnesia carbon brick and preparation method thereof |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101531533A (en) * | 2009-04-22 | 2009-09-16 | 济南鲁东耐火材料有限公司 | Low carbon magnesia carbon brick and preparation method thereof |
| US20100160142A1 (en) * | 2008-12-18 | 2010-06-24 | North American Refractories Company | Refractory brick for steel ladles |
| CN102584277A (en) * | 2012-01-12 | 2012-07-18 | 武汉科技大学 | Low-carbon magnesia carbon bricks and preparation method thereof |
| CN106810210A (en) * | 2016-12-29 | 2017-06-09 | 江苏苏嘉集团新材料有限公司 | Improve magnesia carbon brick of antioxidant and preparation method thereof |
| CN108503381A (en) * | 2018-04-28 | 2018-09-07 | 河南省西峡县冶金辅料有限公司 | A kind of machine pressure assembly type air brick and preparation method thereof |
| KR20200054418A (en) * | 2018-11-09 | 2020-05-20 | (주)포스코케미칼 | Reusable magnesia-carbon refractories |
-
2021
- 2021-06-30 CN CN202110733819.9A patent/CN113387685A/en active Pending
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20100160142A1 (en) * | 2008-12-18 | 2010-06-24 | North American Refractories Company | Refractory brick for steel ladles |
| CN101531533A (en) * | 2009-04-22 | 2009-09-16 | 济南鲁东耐火材料有限公司 | Low carbon magnesia carbon brick and preparation method thereof |
| CN102584277A (en) * | 2012-01-12 | 2012-07-18 | 武汉科技大学 | Low-carbon magnesia carbon bricks and preparation method thereof |
| CN106810210A (en) * | 2016-12-29 | 2017-06-09 | 江苏苏嘉集团新材料有限公司 | Improve magnesia carbon brick of antioxidant and preparation method thereof |
| CN108503381A (en) * | 2018-04-28 | 2018-09-07 | 河南省西峡县冶金辅料有限公司 | A kind of machine pressure assembly type air brick and preparation method thereof |
| KR20200054418A (en) * | 2018-11-09 | 2020-05-20 | (주)포스코케미칼 | Reusable magnesia-carbon refractories |
Non-Patent Citations (4)
| Title |
|---|
| 姜善堂: "《中国•辽宁货典（丹东卷）》", 30 November 1992, 辽宁人民出版社 * |
| 崔更生: "《电弧炉铸钢熔炼》", 31 December 1983, 黑龙江科学技术出版社 * |
| 王泽田等: "《耐火材料技术与发展》", 31 July 1993, 中国轻工业出版社 * |
| 王长明等: "颗粒级配对低碳镁碳砖性能的影响", 《钢铁研究》 * |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115321956A (en) * | 2022-08-19 | 2022-11-11 | 辽宁中镁控股股份有限公司 | High-temperature liquid phase toughened magnesia carbon brick and preparation method thereof |
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