CN116041079A - Tundish covering agent for improving heat preservation performance and preparation method thereof - Google Patents

Tundish covering agent for improving heat preservation performance and preparation method thereof Download PDF

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Publication number
CN116041079A
CN116041079A CN202310090315.9A CN202310090315A CN116041079A CN 116041079 A CN116041079 A CN 116041079A CN 202310090315 A CN202310090315 A CN 202310090315A CN 116041079 A CN116041079 A CN 116041079A
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parts
covering agent
heat preservation
agent
preservation performance
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周文鑫
付凤超
刘习盛
张东风
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Anshan He Feng Refractory Material Co ltd
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Anshan He Feng Refractory Material Co ltd
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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
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    • C04B2235/02—Composition of constituents of the starting material or of secondary phases of the final product
    • C04B2235/30—Constituents and secondary phases not being of a fibrous nature
    • C04B2235/32—Metal oxides, mixed metal oxides, or oxide-forming salts thereof, e.g. carbonates, nitrates, (oxy)hydroxides, chlorides
    • C04B2235/3205—Alkaline earth oxides or oxide forming salts thereof, e.g. beryllium oxide
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    • C04B2235/44—Metal salt constituents or additives chosen for the nature of the anions, e.g. hydrides or acetylacetonate
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Abstract

A tundish covering agent for improving heat preservation performance and a preparation method thereof are prepared from the following raw materials in parts by weight: 10-35 parts of mullite, 40-60 parts of calcareous material, 10-30 parts of premelted material, 3-5 parts of binding agent, 5-10 parts of light burned magnesia, 10-30 parts of dolomite and 1-10 parts of carbonate. The coating agent has the characteristics of high alkalinity, strong capability of removing impurities, no hardening and no erosion of the coating after long-time use, and better heat preservation than a carbon-free calcium-aluminum-magnesium hollow particle coating agent, and can be widely used for the production of various high-added-value steels.

Description

Tundish covering agent for improving heat preservation performance and preparation method thereof
Technical Field
The invention relates to the technical field of metallurgical auxiliary materials, in particular to a tundish covering agent for improving heat preservation performance and a preparation method thereof.
Background
The tundish covering agent is developed from the initial stage of the 60 th century of the 20 th year to the present, and is subjected to an initial acidic covering agent (mainly carbonized rice hulls) with heat insulation performance but unstable heat insulation effect, the performance index is lower, and the tundish covering agent is suitable for common steel grades with low molten steel quality requirements; along with the rapid development of continuous casting, the metallurgical effect of the covering agent is required to be limited to heat preservation, and the covering agent also has the function of removing molten steel inclusions, so that the covering agent is developed into a neutral covering agent (mainly utilizing the defects of boiler slag, fly ash, recycled glass, floating beads, quicklime, perlite, fluorite and the like, but having difficult control of components, weak gettering capability and the like) and an alkaline covering agent which meets the requirements of high-quality steel types at present, wherein the alkaline covering agent has good capability of purifying molten steel, but has poor heat preservation performance, has a heat conductivity coefficient which is 2 times that of an acidic covering agent, and has high melting point and easy crusting. At present, the heat preservation and melting point reduction of the alkaline covering agent are main research subjects. To increase the heat retention, the covering agent undergoes a change in shape from powder, solid particles to hollow particles.
Among the tundish covering agents adopted in various steel mills at present, the covering agents with better performance comprise a carbon-magnesium hollow particle covering agent, a high-alkalinity carbon-free aluminum-calcium hollow particle covering agent and a high-alkalinity carbon-free calcium-aluminum-magnesium hollow particle covering agent:
the carbon-free magnesium hollow particle covering agent has the advantages that the silicon dioxide content is low, the total carbon content is also low, and the erosion to the tundish lining and the stopper rod is light; the defects are high melting point, easy crust formation in use, possibility of influencing control and temperature measurement sampling of the stopper rod in severe cases, limited capability of absorbing inclusions and inapplicability to long-time casting.
The high alkalinity carbon-free aluminum-calcium hollow particle covering agent has the advantages that calcium aluminate is adopted as a base material, the melting point is low, the covering agent is not easy to crust in use, and the calcium-silicon ratio, namely the alkalinity is high, the inclusion absorbing capacity is stronger than that of the calcium-silicon ratio, and the covering agent has a certain desulfurization effect; the low-melting-point calcium aluminate has strong etching effect on the aluminum carbonaceous stopper rod and the magnesium tundish and can cause serious etching on the aluminum carbonaceous stopper rod and the magnesium tundish and is unfavorable for safe production after long-term use, so that the low-melting-point calcium aluminate is not suitable for long-time pouring.
The advantages of the high alkalinity carbon-free calcium aluminum magnesium hollow particle covering agent are basically accumulated, the covering agent has the advantages of high alkalinity, strong capability of removing impurities, no hardening and no erosion of the packing after long-term use, but the heat preservation performance is not ideal, especially the differences of a melting layer, a transition layer and a heat preservation layer which the covering agent should have are basically avoided in the later period of long casting, occasionally, a small amount of covering agent with low melting point is required to be added around a water gap to relieve the covering, so that the stopper rod is ensured not to hang slag.
At present, in order to solve the heat preservation property of the high-alkalinity covering agent, a method for adopting a composite covering agent is adopted, namely, the lower layer is the high-alkalinity covering agent, the upper layer is the acid covering agent with better heat preservation property, but 2 covering agents react after long casting, the quality of molten steel is influenced, and the control is difficult during use.
Hollow particle covering agent with high calcium content is easy to hydrate and generate heat to cause slurry coagulation during production, which prevents smooth production, so that the water quantity is increased at present, but the hollow particles of the sprayed product are obviously reduced, the powder quantity is increased, namely the proportion of the particles is reduced, and the heat preservation effect of the covering agent is seriously affected.
Disclosure of Invention
The invention provides a tundish covering agent for improving heat preservation performance and a preparation method thereof, and the tundish covering agent has the characteristics of high alkalinity, strong capability of removing impurities, no hardening and no erosion of a packing after long-time use, and better heat preservation performance than a carbon-free calcium-aluminum-magnesium hollow particle covering agent, and can be widely applied to the production of various high-added-value steels.
In order to achieve the above purpose, the invention is realized by adopting the following technical scheme:
the tundish covering agent for improving the heat preservation performance is prepared from the following raw materials in parts by weight: 10-35 parts of mullite, 40-60 parts of calcareous material, 10-30 parts of premelted material, 3-5 parts of binding agent, 5-10 parts of light burned magnesia, 10-30 parts of dolomite and 1-10 parts of carbonate.
Preferably, the tundish covering agent for improving the heat preservation performance is prepared from the following raw materials in parts by weight: 15-30 parts of mullite, 40-50 parts of calcareous material, 15-30 parts of premelted material, 3-5 parts of binding agent, 5-10 parts of light burned magnesia, 10-15 parts of dolomite and 4-8 parts of carbonate.
The granularity of the mullite is 180-325 meshes; al in weight percent 2 O 3 The content is 60% -76%; siO (SiO) 2 The content is 20-30%; fe (Fe) 2 O 3 ≤0.5％；P≤0.05％；S≤0.05％。
The volume density of the mullite is 2.8-2.65g/cm 3 The thermal conductivity is 0.25W/m.K at 400 ℃.
The granularity of the calcareous material is 180-400 meshes; 3.5 to 10 percent of the mixture is burned down according to the weight percentage; al (Al) 2 O 3 0.5 to 2 percent; caO is 55% -90%; mgO is 0.5% -1.5%; siO (SiO) 2 1.0 to 5.0 percent; fe (Fe) 2 O 3 ≤0.8％；P≤0.05％；S≤0.05％。
The preparation method of the premelting material comprises the following steps: according to the weight proportion, the calcite is 50-70 parts, the high alumina material (preferably 85 alumina) is 20-30 parts, the active magnesium oxide powder is 3-8 parts, the high alumina cement is 0-5 parts, and the water is 3-5 parts; mixing the above materials, pressing, drying, melting (high temperature melting 1800 deg.C, heating for 8 hr), cooling, and pulverizing into 180-325 mesh fine powder.
The granularity of the calcite is 50-200 meshes; the ignition loss is 38 to 43.5 percent according to the weight percentage; al (Al) 2 O 3 0.5% -1.5%; caO is 48.5% -55%; mgO is 0.5% -1.5%; siO (SiO) 2 0.5% -2.5%; fe (Fe) 2 O 3 0.5% -1.5%. The granularity of the high aluminum material is 50-200 meshes; al in weight percent 2 O 3 80% -85%; siO (SiO) 2 1.0% -7.0%; p is less than or equal to 0.05%; s is less than or equal to 0.05 percent.
The granularity of the active magnesium oxide powder is 180-325 meshes; mgO is 90-95% by weight percent; siO (SiO) 2 1.0% -2.0%; p is less than or equal to 0.05%; s is less than or equal to 0.05 percent.
The granularity of the high alumina cement is 200-400 meshes, and the high alumina cement comprises Al in percentage by weight 2 O 3 45% -50%; caO is 35% -40%; siO (SiO) 2 5.0% -10.0%; p is less than or equal to 0.05%; s is less than or equal to 0.05 percent.
The indexes of the premelted material are as follows: al in weight percent 2 O 3 The content is 15% -30%; siO (SiO) 2 The content is 3% -5%; the CaO content is 50% -65%; mgO content is 3% -7%; p is less than or equal to 0.05%; s is less than or equal to 0.05 percent.
The bonding agent is formed by combining an inorganic bonding agent and an organic bonding agent, and the weight ratio of the inorganic bonding agent to the organic bonding agent is 1:1.5; the inorganic binder is selected from: the organic binding agent is selected from one or more of carboxymethyl cellulose (CMC), dextrin (APA) and hydroxypropyl methylcellulose.
The granularity of the light burned magnesite is 180-325 meshes, and the light burned magnesite is burned down to 1.5-4.5% by weight percent; al (Al) 2 O 3 0.5% -1.5%; caO is 0.5% -3.5%; mgO is 86% -95%; siO (SiO) 2 1.0% -3.5%. The granularity of the dolomite is 180-325 meshes, and the dolomite is burnt down to 43-46% according to the weight percentage; al (Al) 2 O 3 0.5% -1.5%; caO is 29.5% -33%; mgO is 20% -23%; siO (SiO) 2 0.1% -0.5%; fe (Fe) 2 O 3 0.5% -1.5%. The granularity of the carbonate is 50-150 meshes, na 2 CO 3 The content is more than or equal to 98 percent by weight percent.
In order to further improve the heat preservation effect, the invention adds a screening process on the basis of the conventional preparation method of the spray granulation covering agent produced by mullite, and the specific preparation method is as follows:
the binder and the carbonate are firstly dry-mixed for 10 minutes, then the evenly-mixed binder and carbonate are put into a slurry stirring tank for even stirring, (the slurry stirring tank is added with water in advance, the water amount accounts for 55-65% of the total material weight), the rest materials are added successively after even stirring, the net stirring time is required to be more than or equal to 10 minutes, the even stirring of all materials is ensured, and then the materials are put into a slurry storage tank.
Pressurizing the slurry in the slurry storage tank by a plunger pump, and then, feeding the slurry into a spray cyclone drying tower for spray granulation;
granulating, sieving to obtain hollow granule tundish covering agent with granularity of 0.18-2 mmThe bulk specific gravity is significantly reduced to 0.59-0.6g/cm 3 The bulk specific gravity of the screened hollow particle covering agent is smaller than that of the covering agent without screening, and the principle that the smaller the bulk specific gravity of the same substance is, the better the heat preservation effect is utilized, and finally the moisture-proof packaging is carried out.
Physicochemical indexes (weight percent) of the prepared calcium aluminum magnesium carbon-free tundish covering agent are as follows: 15% -25% of burning loss, 20% -45% of CaO and Al 2 O 3 15％-25％、SiO 2 3％-9％、MgO 7％-12％、Fe 2 O 3 0.5 to 0.9 percent, less than or equal to 0.05 percent of P, less than or equal to 0.09 percent of S and less than or equal to 6 percent of TC. The bulk specific gravity of the covering agent is 0.59-0.6g/cm 3 。
The alkalinity of the invention is high: the alkalinity is 5-6.6; the capability of removing impurities is strong: al in molten steel 2 O 3 The inclusion and the calcium oxide in the covering agent can generate low-melting-point compound to be absorbed into the molten covering agent, thereby playing the role of purifying molten steel, and CaO+Al 2 O 3 +high temperature=ca (AlO) 2 ) 2 . The high alkalinity covering agent of the present invention can reduce T [ O ] in steel]Can inhibit molten steel from returning to S and reduce secondary oxidation of molten steel. The low-melting point covering agent has the characteristics of no hardening and no erosion of the packing after long-time use, and has better heat preservation than the carbon-free calcium aluminum magnesium hollow particle covering agent, and can be widely used for the production of various high-added-value steels.
Compared with the prior art, the invention has the beneficial effects that:
1) The invention not only has the advantage of strong gettering capability of the high-alkalinity carbonless calcium aluminum magnesium hollow particle covering agent, but also has the heat preservation performance superior to that of the high-alkalinity carbonless calcium aluminum magnesium hollow particle covering agent, and a small amount of other covering agents with low melting point are not needed to be added around a water gap to relieve crusting so as to ensure that a stopper rod does not hang slag;
2) The invention can be used for long time without crust formation, and can be continuously used for 25 hours at maximum without crust formation.
3) The invention solves the problem that the quality of molten steel is affected when the composite covering agent, namely the acidic covering agent with better heat preservation property is used for a long time, is used for the upper layer.
4) The invention changes the production process, screens the products of the blowing granulation, removes powder, improves the proportion of hollow particles of the products, and contributes to heat preservation.
5) According to the invention, mullite is used as a raw material for producing the covering agent to replace the raw material of high-aluminum bauxite by utilizing the characteristics of small volume density and low heat conductivity coefficient of mullite. The carbon-free calcium aluminum magnesium hollow particle covering agent which meets the metallurgical process requirements of full protection casting of various high-performance steels and has good heat preservation performance is produced.
Detailed Description
The following is a further description of embodiments of the invention, with reference to the examples:
example 1:
the high-alkalinity carbon-free calcium aluminum magnesium hollow particle covering agent is prepared from the following raw materials in parts by weight: 20 parts of mullite, 50 parts of calcareous material, 12 parts of premelted material, 4 parts of bonding agent, 8 parts of light burned magnesia, 20 parts of dolomite and 5 parts of carbonate.
The preparation method comprises the following steps: mixing the bonding agent and the carbonate in advance for 10 minutes, adding the uniformly mixed bonding agent and carbonate into a slurry stirring tank for uniform stirring, (the slurry stirring tank is added with water in advance, the water amount accounts for 55-65% of the total weight of the materials, the specific water amount can be correspondingly adjusted according to specific conditions), the bonding agent and the carbonate are added with the rest materials while stirring after uniform stirring, the net stirring time is more than or equal to 10 minutes, the uniform stirring of all the materials is ensured, and then the materials are placed in a slurry storage tank; pressurizing the slurry in the slurry storage tank by a plunger pump, and then, feeding the slurry into a spray cyclone drying tower for spray granulation; sieving after granulation to obtain spray granulation particles with the granularity of 0.18-2 mm, namely the calcium aluminum magnesium tundish covering agent, which ensures that the finished product is hollow particles and the bulk specific gravity of the product is 0.59-0.6g/cm 3 And finally, carrying out dampproof packaging.
Physicochemical indexes (weight percent) of the prepared calcium aluminum magnesium carbon-free tundish covering agent are as follows: 15% -25% of burning loss, 20% -45% of CaO and Al 2 O 3 15％-25％、SiO 2 3％-9％、MgO 7％-12％、Fe 2 O 3 0.5％-0.9％、PLess than or equal to 0.05 percent, less than or equal to 0.09 percent of S and less than or equal to 6 percent of TC. The bulk specific gravity of the product is 0.59-0.6g/cm 3 。
Example 2:
the high-alkalinity carbon-free calcium aluminum magnesium hollow particle covering agent is prepared from the following raw materials in parts by weight: 22 parts of mullite, 45 parts of calcareous material, 18 parts of premelted material, 3.5 parts of bonding agent, 7 parts of light burned magnesia, 13 parts of dolomite and 6 parts of carbonate.
The preparation method comprises the following steps: mixing the bonding agent and the carbonate in advance for 10 minutes, adding the uniformly mixed bonding agent and carbonate into a slurry stirring tank for uniform stirring, (the slurry stirring tank is added with water in advance, the water amount accounts for 55-65% of the total weight of the materials, the specific water amount can be correspondingly adjusted according to specific conditions), the bonding agent and the carbonate are added with the rest materials while stirring after uniform stirring, the net stirring time is more than or equal to 10 minutes, the uniform stirring of all the materials is ensured, and then the materials are placed in a slurry storage tank; pressurizing the slurry in the slurry storage tank by a plunger pump, and then, feeding the slurry into a spray cyclone drying tower for spray granulation; at this time, the bulk specific gravity of the sampled product is 0.68-0.65g/cm 3 ；
Sieving after granulating to obtain spray granulated particles with the granularity of 0.18-2 mm, namely the high-alkalinity carbon-free calcium aluminum magnesium hollow particle covering agent, ensuring that the finished product is hollow particles, wherein the bulk specific gravity of the product is 0.59-0.6g/cm 3 And (5) cube, and finally, carrying out moistureproof packaging.
The prepared calcium aluminum magnesium carbon-free tundish covering agent comprises the following chemical components in percentage by weight: 15-25% of burning loss, 20-45% of CaO and Al 2 O 3 15-25％、SiO 2 3-9％、MgO7-12％、Fe 2 O 3 0.5-0.9％、P≤0.05％、S≤0.09％、TC≤6％。
Comparative example 1:
the raw material formulation of the high alkalinity non-carbon calcium aluminum magnesium hollow particle covering agent prepared in the comparative example is the same as that of example 2, and the preparation method is not screened and uses bulk specific gravity of 0.68-0.65g/cm 3 Is a product of (a).
Comparative example 2:
high alkalinity carbon-free calcium aluminum magnesium hollow particle coatingThe cover agent uses alumina to replace mullite as raw material, other raw materials and proportions are the same as those of the embodiment 2, sieving is not carried out after granulation in the preparation method, and the bulk specific gravity of the product is as follows: 0.76.+ -. 0.02g/cm 3 。
Example 2 and comparative example 1, comparative example 2 are shown in table 1;
table 1:
Figure BDA0004070081660000061
the average temperature of molten steel was 1540 ℃ in the tundish casting of comparative example 2; the average temperature of molten steel for tundish casting in comparative example 1 was 1547 ℃; the tundish used in the invention of example 2 was used to cast molten steel at an average temperature of 1550 ℃; therefore, the heat preservation effect of the covering agent added with mullite is better than that of the covering agent added with alumina when the covering agent added with mullite is used, and the heat preservation effect of the covering agent added with mullite after sieving is better than that of the covering agent added with mullite without sieving. The high-alkalinity carbon-free calcium aluminum magnesium hollow particle covering agent has good heat preservation effect.
The ladle inversion comparison after use of example 2, comparative example 1 and comparative example 2, found that the slag layer change further demonstrates the superior performance of a tundish covering agent of the present invention for improving the heat retention performance: the covering agent slag layer of comparative example 2 is basically integrated without hierarchy; the slag layer of comparative example 1 has obvious level change, and the level of change indicates that the covering agent is divided into three layers in the use process: the melting layer, the transition layer and the heat preservation layer play a role in heat preservation; the slag layer change of the embodiment 2 of the invention is more obvious: a melting layer, a transition layer and a heat preservation layer; the melting layer is completely melted, the molten steel is adsorbed and purified, the transition layer consists of a melted covering agent and an unmelted covering agent, and the heat preservation layer is completely unmelted, so that a good heat preservation effect is achieved.
The high alkalinity carbon-free calcium aluminum magnesium hollow particle covering agent of the invention can absorb inclusions in molten steel to the maximum extent, especially for aluminum deoxidized killed steel, al in molten steel 2 O 3 Covering agent in which inclusions are absorbed into molten state with calcium oxide in the covering agent to form a low-melting compoundThe device has the function of purifying molten steel. CaO+Al 2 O 3 +high temperature=ca (AlO) 2 ) 2 。
The high alkalinity covering agent of the present invention can reduce T [ O ] in steel, inhibit molten steel from returning S and reduce secondary oxidation of molten steel.
The above examples 1 and 2 were verified in Liaoning steel works and Sichuan steel works, respectively, and the use effect was good, and it was possible to meet the requirement of continuous casting of 25 cans of molten steel at most, to average 260 tons of molten steel in a single can, and to average the casting of a single can for 1 hour. The steel mill continuous casting process has the advantages that the steel mill continuous casting process is free from crusting (namely, a small amount of other covering agents with low melting points are not needed to be added around the water gap to relieve crusting) and free from smoking, and the continuous casting process completely meets the continuous casting production requirements of the steel mill.

Claims (10)

1. The tundish covering agent for improving the heat preservation performance is characterized by being prepared from the following raw materials in parts by weight: 10-35 parts of mullite, 40-60 parts of calcareous material, 10-30 parts of premelted material, 3-5 parts of binding agent, 5-10 parts of light burned magnesia, 10-30 parts of dolomite and 1-10 parts of carbonate.
2. The tundish covering agent for improving heat preservation performance according to claim 1 is characterized by being prepared from the following raw materials in parts by weight: 15-30 parts of mullite, 40-50 parts of calcareous material, 15-30 parts of premelted material, 3-5 parts of binding agent, 5-10 parts of light burned magnesia, 10-15 parts of dolomite and 4-8 parts of carbonate.
3. The tundish covering agent for improving heat preservation performance according to claim 1 or 2, wherein the mullite grain size is 180-325 meshes; al in weight percent 2 O 3 The content is 60% -76%; siO (SiO) 2 The content is 20-30%; fe (Fe) 2 O 3 ≤0.5％；P≤0.05％；S≤0.05％。
4. The tundish covering agent for improving heat preservation performance according to claim 1 or 2, wherein the mullite volume density is 2.8-2.65g/cm 3 The thermal conductivity is 0.25W/m.K at 400 ℃.
5. The tundish covering agent for improving heat preservation performance according to claim 1 or 2, wherein the granularity of the calcareous material is 180-400 meshes; 3.5 to 10 percent of the mixture is burned down according to the weight percentage; al (Al) 2 O 3 0.5 to 2 percent; caO is 55% -90%; mgO is 0.5% -1.5%; siO (SiO) 2 1.0 to 5.0 percent; fe (Fe) 2 O 3 ≤0.8％；P≤0.05％；S≤0.05％。
6. The tundish covering agent for improving heat preservation performance according to claim 1 or 2, wherein the preparation method of the premelt material is as follows: the weight proportion of the cement is 50 to 70 parts of calcite, 20 to 30 parts of high aluminum material, 3 to 8 parts of active magnesia powder, 0 to 5 parts of high aluminum cement and 3 to 5 parts of water; mixing the above materials, pressing, drying, melting, cooling, and pulverizing into 180-325 mesh fine powder.
7. The tundish covering agent for improving heat preservation performance according to claim 6, wherein the granularity of calcite is 50-200 meshes; the granularity of the high aluminum material is 50-200 meshes; the granularity of the active magnesium oxide powder is 180-325 meshes; the granularity of the high alumina cement is 200-400 meshes.
8. The tundish covering agent for improving heat preservation performance according to claim 1 or 2, wherein the bonding agent is formed by combining an inorganic bonding agent and an organic bonding agent, and the weight ratio of the inorganic bonding agent to the organic bonding agent is 1:1.5; the inorganic binder is selected from: the organic binding agent is selected from one or more of carboxymethyl cellulose, dextrin and hydroxypropyl methylcellulose.
9. The tundish covering agent for improving heat preservation performance according to claim 1 or 2, wherein the light burned magnesia has a granularity of 180-325 meshes, the dolomite has a granularity of 180-325 meshes, and the carbonate has a granularity of 50-150 meshes.
10. A method for preparing a tundish covering agent for improving heat preservation performance as claimed in any one of claims 1 to 9, comprising: the preparation method comprises the steps of firstly dry-mixing a bonding agent and carbonate, adding water into the uniformly mixed bonding agent and carbonate, stirring uniformly, adding the rest materials, stirring uniformly, and preparing the hollow granular covering agent through a spray drying tower; and (3) sieving after granulating to obtain the hollow particle tundish covering agent with the granularity of 0.18-2 mm.
CN202310090315.9A 2023-02-09 2023-02-09 Tundish covering agent for improving heat preservation performance and preparation method thereof Pending CN116041079A (en)

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Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH02211953A (en) * 1989-02-13 1990-08-23 Nippon Steel Corp Inclusion refining agent for continuous casting tundish having heat holding property
CN102259175A (en) * 2011-07-16 2011-11-30 鞍山市和丰耐火材料有限公司 Production method for Ca-Al-Mg carbon-free tundish covering flux
CN103586426A (en) * 2013-10-30 2014-02-19 吴江市液铸液压件铸造有限公司 Thermal-insulation cover agent and preparation method thereof
CN106984716A (en) * 2017-06-10 2017-07-28 黄国新 A kind of diel drift
CN109369160A (en) * 2018-12-04 2019-02-22 钢城集团凉山瑞海实业有限公司 Tundish cover castable
CN111995410A (en) * 2020-08-24 2020-11-27 武汉钢铁集团耐火材料有限责任公司 Lightweight moisturizing and heat-insulating pouring material for tundish cover and preparation method thereof
CN114045407A (en) * 2021-11-02 2022-02-15 山东博源精密机械有限公司 Preparation method of microalloy aluminum for low-segregation-degree motor rotor of new energy automobile and microalloy aluminum prepared by preparation method

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH02211953A (en) * 1989-02-13 1990-08-23 Nippon Steel Corp Inclusion refining agent for continuous casting tundish having heat holding property
CN102259175A (en) * 2011-07-16 2011-11-30 鞍山市和丰耐火材料有限公司 Production method for Ca-Al-Mg carbon-free tundish covering flux
CN103586426A (en) * 2013-10-30 2014-02-19 吴江市液铸液压件铸造有限公司 Thermal-insulation cover agent and preparation method thereof
CN106984716A (en) * 2017-06-10 2017-07-28 黄国新 A kind of diel drift
CN109369160A (en) * 2018-12-04 2019-02-22 钢城集团凉山瑞海实业有限公司 Tundish cover castable
CN111995410A (en) * 2020-08-24 2020-11-27 武汉钢铁集团耐火材料有限责任公司 Lightweight moisturizing and heat-insulating pouring material for tundish cover and preparation method thereof
CN114045407A (en) * 2021-11-02 2022-02-15 山东博源精密机械有限公司 Preparation method of microalloy aluminum for low-segregation-degree motor rotor of new energy automobile and microalloy aluminum prepared by preparation method

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