CN112301180A - Method for alloying manganese in ultrahigh manganese steel in non-electric furnace aluminum heating mode - Google Patents
Method for alloying manganese in ultrahigh manganese steel in non-electric furnace aluminum heating mode Download PDFInfo
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- CN112301180A CN112301180A CN202011046510.4A CN202011046510A CN112301180A CN 112301180 A CN112301180 A CN 112301180A CN 202011046510 A CN202011046510 A CN 202011046510A CN 112301180 A CN112301180 A CN 112301180A
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- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21C—PROCESSING OF PIG-IRON, e.g. REFINING, MANUFACTURE OF WROUGHT-IRON OR STEEL; TREATMENT IN MOLTEN STATE OF FERROUS ALLOYS
- C21C1/00—Refining of pig-iron; Cast iron
- C21C1/02—Dephosphorising or desulfurising
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- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21C—PROCESSING OF PIG-IRON, e.g. REFINING, MANUFACTURE OF WROUGHT-IRON OR STEEL; TREATMENT IN MOLTEN STATE OF FERROUS ALLOYS
- C21C5/00—Manufacture of carbon-steel, e.g. plain mild steel, medium carbon steel or cast steel or stainless steel
- C21C5/28—Manufacture of steel in the converter
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- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21C—PROCESSING OF PIG-IRON, e.g. REFINING, MANUFACTURE OF WROUGHT-IRON OR STEEL; TREATMENT IN MOLTEN STATE OF FERROUS ALLOYS
- C21C7/00—Treating molten ferrous alloys, e.g. steel, not covered by groups C21C1/00 - C21C5/00
- C21C7/0006—Adding metallic additives
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- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21C—PROCESSING OF PIG-IRON, e.g. REFINING, MANUFACTURE OF WROUGHT-IRON OR STEEL; TREATMENT IN MOLTEN STATE OF FERROUS ALLOYS
- C21C7/00—Treating molten ferrous alloys, e.g. steel, not covered by groups C21C1/00 - C21C5/00
- C21C7/005—Treating molten ferrous alloys, e.g. steel, not covered by groups C21C1/00 - C21C5/00 using exothermic reaction compositions
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- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21C—PROCESSING OF PIG-IRON, e.g. REFINING, MANUFACTURE OF WROUGHT-IRON OR STEEL; TREATMENT IN MOLTEN STATE OF FERROUS ALLOYS
- C21C7/00—Treating molten ferrous alloys, e.g. steel, not covered by groups C21C1/00 - C21C5/00
- C21C7/04—Removing impurities by adding a treating agent
- C21C7/06—Deoxidising, e.g. killing
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- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21C—PROCESSING OF PIG-IRON, e.g. REFINING, MANUFACTURE OF WROUGHT-IRON OR STEEL; TREATMENT IN MOLTEN STATE OF FERROUS ALLOYS
- C21C7/00—Treating molten ferrous alloys, e.g. steel, not covered by groups C21C1/00 - C21C5/00
- C21C7/04—Removing impurities by adding a treating agent
- C21C7/068—Decarburising
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- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C33/00—Making ferrous alloys
- C22C33/04—Making ferrous alloys by melting
- C22C33/06—Making ferrous alloys by melting using master alloys
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- Materials Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
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- Manufacturing & Machinery (AREA)
- Carbon Steel Or Casting Steel Manufacturing (AREA)
- Treatment Of Steel In Its Molten State (AREA)
Abstract
The invention belongs to the technical field of metallurgy, and particularly relates to a method for alloying manganese in an ultra-high manganese steel non-electric furnace aluminum heating mode. The invention provides a method for ultrahigh manganese steel non-electric furnace aluminum heating mode manganese alloying, which utilizes the excellent dynamic condition of a converter for quick decarburization and the chemical heat generated by oxidation exothermic reaction of oxygen and a large amount of alloy elements such as ferrosilicon, aluminum particles and the like in the oxygen blowing process in the converter process to replace electric furnace electric energy heat for melting manganese alloy.
Description
Technical Field
The invention belongs to the technical field of metallurgy, and particularly relates to a method for alloying manganese in an ultra-high manganese steel non-electric furnace aluminum heating mode.
Background
The high manganese steel has the characteristics of excellent welding performance and high strength of carbon steel, high extensibility, non-magnetism, deformation induction and the like of stainless steel, the high manganese steel for sound insulation of buildings, the high manganese non-magnetic steel for transformers and the high manganese steel for ultralow temperature pressure vessels are taken as representatives of the high manganese steel and become hot spots of global research, the manganese content in the high manganese steel is 20-25%, the chromium and nickel content is replaced by the manganese content, and the high manganese steel is the stainless steel in the carbon steel.
The most difficult problem in the smelting production of high manganese steel is manganese alloying, the traditional process adopts an electric furnace or an intermediate frequency furnace to complete manganese alloying, 30-40 tons of electrolytic manganese needs to be added into 100 tons of electric furnace to ensure that the manganese content of molten steel reaches 20-25 percent, the manganese alloying period is long, the manganese yield is poor, the cost is high, and in addition, the dynamic condition of the electric furnace or the intermediate frequency furnace is poor, so that the flowability and the component uniformity of the molten steel are poor. In order to solve the above problems, it is necessary to find a manganese alloying technique which is shorter and more economical than the conventional technique.
Disclosure of Invention
The invention aims to provide a method for alloying manganese in an aluminum heating mode of an ultra-high manganese steel non-electric furnace aiming at the current situation of the prior art so as to solve the problems in the prior art.
In order to achieve the purpose, the invention specifically adopts the following technical scheme:
a method for alloying manganese in an ultra-high manganese steel non-electric furnace aluminum heating mode comprises the following steps:
s1, pretreating molten iron, wherein the initial carbon content of the dephosphorized molten iron is generally 2.8-3.5%, the initial temperature is generally 1350-1400 ℃, carrying out dephosphorization treatment on the molten iron in a blast furnace, creating conditions for subsequent smelting, and removing phosphorus to be below 0.0015%, and simultaneously, ensuring that the temperature of the molten iron reaches above the carbon-manganese conversion temperature when a high-carbon ferromanganese alloy is added so as to maximally realize the aims of decarbonization and manganese preservation.
S2, main decarburization heating: adding molten iron with four fifths of total tapping amount for removing P, starting blowing, adding coke in the process, increasing the temperature in the furnace, and side-blowing O2And Ar, the end point carbon content reaching a target value.
S3, primary manganese alloying: the MnO is increased to thin the slag in the oxidation stage, the CO is influenced to escape, the decarburization is difficult, and the alloying of the manganese is carried out in two stages.
S4, decarburization and deoxidation: adjusting O2: and (3) carrying out dynamic decarburization on the proportion of Ar, blowing to the end point, adding Al particles, deoxidizing the molten steel, adding electrolytic manganese into the furnace in batches, adding a small amount of Al particles when adding each batch of electrolytic manganese, and heating and adjusting the components of the molten steel.
S5, secondary manganese alloying: the method comprises the steps of adding electrolytic manganese with higher purity in 3-4 batches, adding 4-5 tons of electrolytic manganese in each batch, adding 3kg/t of aluminum particles for oxidation and heating, sampling and measuring components, fine-adjusting according to a detection result, feeding SiCaBa wire for performing modification treatment on aluminum oxide, discharging after weak blowing homogenization treatment, reducing and slagging off after discharging to obtain qualified manganese alloying molten steel, and continuously casting the molten steel in an LF furnace.
Further, in the step S1, the content of manganese in the ultrahigh manganese steel is 25-32% by weight.
Further, theSide blowing lance O in step S22The Ar proportion is controlled according to 1: 1-2 and 1: 1-3 respectively, the end point carbon content reaches a target value of 0.30-0.38%, and the end point carbon content is actually adjusted according to different high manganese steel carbon contents.
Further, the two stages of the manganese alloying in step S3 are: in the primary manganese alloying, 2-4 tons of high-carbon ferromanganese with better economy is firstly added, top lance oxygen supply is cancelled, oxygen and argon mixed gas is laterally blown, then 1-3 tons of electrolytic manganese with higher purity are added, and the end point carbon content is controlled to be 0.30-0.38%.
Further, in the step S4, O is adjusted2: and (3) carrying out dynamic decarburization according to the proportion of Ar, blowing till the end point carbon is 0.15-0.19%, adding Al particles, deoxidizing the molten steel, adding electrolytic manganese into the furnace in batches, adding a small amount of Al particles when 4-5 tons of electrolytic manganese are added in each batch, and heating and adjusting the components of the molten steel. Adjusting O in the process2: ratio of Ar 3: 1-5: 1, reducing oxygen, increasing argon, increasing stirring power, and blowing a flow field of the molten steel by using gas to rapidly melt the manganese alloy into the molten steel.
Compared with the prior art, the invention has the beneficial effects that:
1) the molten iron S, P after the de-P treatment is low, the load of a subsequent converter is reduced, the production efficiency of the converter is improved, and the smelting period is shortened.
2) The converter side-blown oxygen-argon mixed gas with different proportions is utilized to reduce the partial pressure of CO, so that the high-efficiency decarburization is realized, and meanwhile, the high manganese metal yield can be obtained by utilizing the good side-blown dynamic conditions of the converter.
3) Heating elements of coke and aluminum particles are added, the heat in the converter is sufficient, the dynamic condition is good, the rapid alloying is realized, and the smelting period is short;
4) when manganese is alloyed twice in the converter, part of high-carbon manganese alloy is added firstly, alloying is realized, part of carbon elements can be provided to achieve the effect of temperature rise, the alloy cost can be saved, and the manganese content in steel is ensured by electrolytic manganese added later.
5) The method solves the problems of low decarburization efficiency, long smelting period and low metal yield of the original process in the manganese alloying process of the high manganese steel, provides reasonable process matching time for the subsequent continuous casting process, shortens the production process flow, effectively reduces the production cost, greatly releases the smelting capacity, obtains remarkable economic benefit and has important popularization value.
Detailed Description
The technical solutions in the embodiments of the present invention are clearly and completely described below, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all embodiments.
In order to achieve the purpose, the invention specifically adopts the following technical scheme.
A method for alloying manganese in an ultra-high manganese steel non-electric furnace aluminum heating mode comprises the following steps:
the process flow comprises the following steps: molten iron pretreatment → main decarburization heating → primary manganese alloying → deoxidation → secondary manganese alloying → reduction → slag skimming → qualified manganese alloyed molten steel → LF → continuous casting.
The initial carbon content of the dephosphorized molten iron in the molten iron pretreatment is generally 2.8-3.5%, the initial temperature is generally 1350-1400 ℃, the dephosphorization treatment of the molten iron in the blast furnace creates conditions for subsequent smelting, the phosphorus content is reduced to be below 0.0015%, and simultaneously, the temperature of the molten iron reaches above the carbon-manganese conversion temperature when the high-carbon ferromanganese alloy is added, so that the aims of decarbonization and manganese preservation are fulfilled to the maximum extent.
And adding the dephosphorized molten iron with the total steel tapping amount of 4/5 in the main decarburization temperature rising process, starting blowing, adding coke in the process, and increasing the temperature in the furnace. This stage O2: high proportion of Ar, large total gas amount, side-blown air gun O2The Ar proportion is controlled according to 1: 1-2 and 1: 1-3 respectively, the end point carbon content reaches a target value of 0.30-0.38%, and the end point carbon content is actually adjusted according to different high manganese steel carbon contents.
In the primary manganese alloying process, the MnO content is continuously increased, so that slag is thinned in an oxidation stage, CO escaping is influenced, and decarburization is difficult. Alloying of manganese is carried out in two stages, 2-4 tons of high-carbon ferromanganese with better economy is added in one-time manganese alloying, top gun oxygen supply is cancelled, oxygen and argon mixed gas is blown laterally, then 1-3 tons of electrolytic manganese with higher purity are added, and the end point carbon content is controlled to be 0.30-0.38%.
Adjusting O in the decarburization deoxidation2: and (3) carrying out dynamic decarburization on the proportion of Ar, blowing to 0.15-0.19% of the end point, adding Al particles, deoxidizing the molten steel, adding electrolytic manganese into the furnace in batches, adding a small amount of Al particles when 4-5 tons of electrolytic manganese are added in each batch, and heating and adjusting the components of the molten steel. Adjusting O in the process2: ratio of Ar 3: 1-5: 1, reducing oxygen, increasing argon, increasing stirring power, and blowing a flow field of the molten steel by using gas to rapidly melt the manganese alloy into the molten steel.
Electrolytic manganese with higher purity is used in the secondary manganese alloying, the electrolytic manganese is added in 3-4 batches, 4-5 tons of electrolytic manganese are added in each batch, 3kg/t of aluminum particles are added for oxidation and temperature rise, sampling is carried out, components are measured, fine adjustment is carried out according to a detection result, SiCaBa wires are fed for carrying out denaturation treatment on aluminum oxide, the aluminum oxide is discharged after weak blowing homogenization treatment, qualified manganese alloying molten steel is obtained after reduction and slag removal after the aluminum oxide is discharged, and the molten steel is continuously cast by an LF furnace.
The chemical compositions, manganese yields and smelting time of the steel grades with six different manganese contents in the examples are listed in table 1, and the specific changes are shown in the following table:
as can be seen from the table 1, the steel grade of the example passes 6 tests, the manganese content is 25-32%, the manganese yield is increased from 75.3% to 92-98%, and the smelting time is gradually reduced from 378 minutes to about 80 minutes, so that the steel grade is in a stable state.
The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents and improvements made within the spirit and principle of the present invention are intended to be included within the scope of the present invention.
Claims (5)
1. A method for alloying manganese in an ultra-high manganese steel non-electric furnace aluminum heating mode comprises the following steps:
s1, pretreating molten iron, wherein the initial carbon content of the dephosphorized molten iron is generally 2.8-3.5%, the initial temperature is generally 1350-1400 ℃, carrying out dephosphorization treatment on the molten iron in a blast furnace, creating conditions for subsequent smelting, and removing phosphorus to be below 0.0015%, and simultaneously, ensuring that the temperature of the molten iron reaches above the carbon-manganese conversion temperature when a high-carbon ferromanganese alloy is added so as to maximally realize the aims of decarbonization and manganese preservation.
S2, main decarburization heating: adding molten iron with four fifths of total tapping amount for removing P, starting blowing, adding coke in the process, increasing the temperature in the furnace, and side-blowing O2And Ar, the end point carbon content reaching a target value.
S3, primary manganese alloying: the MnO is increased to thin the slag in the oxidation stage, the CO is influenced to escape, the decarburization is difficult, and the alloying of the manganese is carried out in two stages.
S4, decarburization and deoxidation: adjusting O2: and (3) carrying out dynamic decarburization on the proportion of Ar, blowing to the end point, adding Al particles, deoxidizing the molten steel, adding electrolytic manganese into the furnace in batches, adding a small amount of Al particles when adding each batch of electrolytic manganese, and heating and adjusting the components of the molten steel.
S5, secondary manganese alloying: the method comprises the steps of adding electrolytic manganese with higher purity in 3-4 batches, adding 4-5 tons of electrolytic manganese in each batch, adding 3kg/t of aluminum particles for oxidation and heating, sampling and measuring components, fine-adjusting according to a detection result, feeding SiCaBa wire for performing modification treatment on aluminum oxide, discharging after weak blowing homogenization treatment, reducing and slagging off after discharging to obtain qualified manganese alloying molten steel, and continuously casting the molten steel in an LF furnace.
2. The method for alloying manganese in the ultra-high manganese steel non-electric furnace aluminum heating mode according to claim 1, characterized in that: in the step S1, the manganese content of the ultrahigh manganese steel is 25-32% by weight.
3. The method for alloying manganese in the ultra-high manganese steel non-electric furnace aluminum heating mode according to claim 1, characterized in that: the side blowing lance O in the step S22The Ar proportion is controlled according to 1: 1-2 and 1: 1-3 respectively, the end point carbon content reaches a target value of 0.30-0.38%, and the end point carbon content is actually adjusted according to different high manganese steel carbon contents.
4. The method for alloying manganese in the ultra-high manganese steel non-electric furnace aluminum heating mode according to claim 1, characterized in that: the two stages of the manganese alloying in step S3 are: in the primary manganese alloying, 2-4 tons of high-carbon ferromanganese with better economy is firstly added, top lance oxygen supply is cancelled, oxygen and argon mixed gas is laterally blown, then 1-3 tons of electrolytic manganese with higher purity are added, and the end point carbon content is controlled to be 0.30-0.38%.
5. The method for alloying manganese in the ultra-high manganese steel non-electric furnace aluminum heating mode according to claim 1, characterized in that: adjusting O in said step S42: dynamically decarbonizing the Ar according to the proportion, blowing till the end point carbon is 0.15-0.19%, adding Al particles, deoxidizing the molten steel, adding electrolytic manganese into the furnace in batches, adding a small amount of Al particles when 4-5 tons of electrolytic manganese are added in each batch, heating the molten steel, adjusting the components, and adjusting O in the process2: ratio of Ar 3: 1-5: 1, reducing oxygen, increasing argon, increasing stirring power, and blowing a flow field of the molten steel by using gas to rapidly melt the manganese alloy into the molten steel.
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| CN202011046510.4A CN112301180A (en) | 2020-09-29 | 2020-09-29 | Method for alloying manganese in ultrahigh manganese steel in non-electric furnace aluminum heating mode |
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Citations (6)
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| JP2005015890A (en) * | 2003-06-27 | 2005-01-20 | Jfe Steel Kk | Method for producing low-carbon high-manganese steel |
| JP2005060782A (en) * | 2003-08-15 | 2005-03-10 | Jfe Steel Kk | Method for smelting low-carbon high-manganese steel |
| CN101057001A (en) * | 2005-12-02 | 2007-10-17 | 西马克·德马格公司 | Method for producing steel with high manganese and low carbon content and smelter |
| JP2011153328A (en) * | 2010-01-26 | 2011-08-11 | Jfe Steel Corp | Method for smelting low-carbon high-manganese steel |
| CN103468874A (en) * | 2013-08-20 | 2013-12-25 | 北京科技大学 | Method for manufacturing low-carbon TWIP steel through AOD (argon oxygen decarburization) furnace |
| CN105039648A (en) * | 2015-08-04 | 2015-11-11 | 上海应用技术学院 | Method for smelting low-carbon and high-manganese-content molten steel through argon oxygen decarburizing furnace |
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2020
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Patent Citations (6)
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| JP2005015890A (en) * | 2003-06-27 | 2005-01-20 | Jfe Steel Kk | Method for producing low-carbon high-manganese steel |
| JP2005060782A (en) * | 2003-08-15 | 2005-03-10 | Jfe Steel Kk | Method for smelting low-carbon high-manganese steel |
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| JP2011153328A (en) * | 2010-01-26 | 2011-08-11 | Jfe Steel Corp | Method for smelting low-carbon high-manganese steel |
| CN103468874A (en) * | 2013-08-20 | 2013-12-25 | 北京科技大学 | Method for manufacturing low-carbon TWIP steel through AOD (argon oxygen decarburization) furnace |
| CN105039648A (en) * | 2015-08-04 | 2015-11-11 | 上海应用技术学院 | Method for smelting low-carbon and high-manganese-content molten steel through argon oxygen decarburizing furnace |
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