CN114875301B - Chromium stainless steel and preparation method thereof - Google Patents
Chromium stainless steel and preparation method thereof Download PDFInfo
- Publication number
- CN114875301B CN114875301B CN202210493593.4A CN202210493593A CN114875301B CN 114875301 B CN114875301 B CN 114875301B CN 202210493593 A CN202210493593 A CN 202210493593A CN 114875301 B CN114875301 B CN 114875301B
- Authority
- CN
- China
- Prior art keywords
- steel
- chromium
- aod
- stainless steel
- oxygen
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Classifications
-
- 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
-
- 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
- C21C5/005—Manufacture of stainless steel
-
- 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
- C21C7/064—Dephosphorising; Desulfurising
-
- 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
- C21C7/0685—Decarburising of stainless steel
-
- 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
- C21C7/072—Treatment with gases
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/02—Ferrous alloys, e.g. steel alloys containing silicon
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/04—Ferrous alloys, e.g. steel alloys containing manganese
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P10/00—Technologies related to metal processing
- Y02P10/20—Recycling
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Mechanical Engineering (AREA)
- Manufacturing & Machinery (AREA)
- Treatment Of Steel In Its Molten State (AREA)
- Carbon Steel Or Casting Steel Manufacturing (AREA)
Abstract
The invention belongs to the technical field of stainless steel smelting, and relates to chromium stainless steel and a preparation method thereof. The preparation method of the chromium stainless steel comprises the following steps: melting high-carbon ferrochrome and carbon scrap steel by adopting an intermediate frequency furnace to obtain high-silicon chromium-containing molten iron premelt; adding the high-silicon chromium-containing molten iron premelting solution into an AOD, and sequentially carrying out an AOD desilication procedure, a deslagging procedure, an AOD decarburization procedure and a deslagging procedure to obtain first molten steel; transferring the first molten steel into an LF furnace for refining to obtain second molten steel; and continuously casting the second molten steel to obtain a chromium stainless steel slab. According to the preparation method of the chromium stainless steel, desilication, decarbonization and reduction smelting of the chromium stainless steel are carried out in the same AOD, and as the converter desilication process is not adopted, the steel tapping temperature drop in the process is reduced, and meanwhile, the silicon oxidation heat is fully utilized to melt the scrap steel, so that the addition amount of cold materials in the AOD is increased, and the effective utilization of heat is realized.
Description
Technical Field
The invention belongs to the technical field of stainless steel smelting, relates to chromium stainless steel and a preparation method thereof, and particularly relates to a chromium-containing molten iron desilication process and a method for producing the chromium stainless steel by adopting the same.
Background
The chromium-series stainless steel is also called 400-series stainless steel, is a ferrochrome alloy containing more than 10% of chromium, and the varieties comprise 430, 410, 420, 409L and the like, and in oxidizing media such as atmosphere, fresh water and nitric acid, the corrosion resistance is basically the same as that of 300-series stainless steel, and the deep drawability, weldability, corrosion resistance and high-temperature strength of the stainless steel can be improved by adding trace elements such as niobium, titanium, copper, aluminum and the like, and the stainless steel can partially replace 300-series stainless steel, so that the 400-series stainless steel can be widely applied to the industrial fields of automobile exhaust pipes, elevators, washing machine inner cylinders, kitchenware, household electrical appliances, house top plates, curtain walls, power plant equipment and the like. The nickel-free alloy is low in price and is popular with people because the nickel-free alloy does not contain noble element nickel.
The conventional 400 series stainless steel smelting method at present adopts blast furnace molten iron to carry out desilication and dephosphorization in a pretreatment process, then adds the blast furnace molten iron into an AOD/KOBM/GOR furnace, and then adds high-carbon ferrochrome to carry out blowing, and has the defects that the high-Si ferrochrome is not suitable for the AOD process or the front process, and a large amount of low-cost chromium waste cannot be used, otherwise, the problems of high silicon content, difficult decarburization, large slag quantity, low temperature, high reduction silicon consumption and the like in steel are caused. In order to solve the problems, two methods exist in China, namely, after dephosphorized molten iron is added into an AOD furnace for pretreatment, an intermediate frequency furnace or an electric furnace is adopted to melt high-carbon ferrochrome (or waste chromium) and then added into the AOD, and the heat is not enough. Another is a method for smelting ferrite stainless steel by using furnace charge ferrochrome disclosed in the invention patent application with publication number of CN 107829016A, which adopts an electric furnace/intermediate frequency furnace to melt raw materials such as furnace charge ferrochrome and waste chromium and the like to prepare chromium-containing molten iron, and adds the chromium-containing molten iron into a converter to carry out desilication operation, and then adds the desilicated molten iron into an AOD for smelting.
Disclosure of Invention
The invention aims at overcoming the defects of the prior art and provides chromium stainless steel and a preparation method thereof.
Specifically, the preparation method of the chromium stainless steel comprises the following steps:
s1, melting high-carbon ferrochrome and carbon scrap steel by adopting an intermediate frequency furnace to obtain high-silicon ferrochrome-containing molten iron premelt;
s2, adding the high-silicon chromium-containing molten iron premelting solution into an AOD, and sequentially carrying out an AOD desilication procedure, a deslagging procedure, an AOD decarburization procedure and a deslagging procedure to obtain first molten steel;
s3, transferring the first molten steel into an LF furnace for refining to obtain second molten steel;
and S4, continuously casting the second molten steel to obtain a chromium stainless steel slab.
The above-mentioned chromium stainless steel preparation method, the said AOD desilication process includes:
s11, adding the high-silicon chromium-containing molten iron premelt into an AOD furnace, adding carbon scrap steel and lime, then top-blowing oxygen, side-blowing oxygen and nitrogen, and converting for 5-8min;
s12, adding carbon scrap steel or chromium scrap steel in a second tank, adding lime, converting for 10-12min, stopping top-blowing oxygen, gradually reducing the proportion of side-blowing oxygen, and controlling the slag alkalinity to be 1.2-1.4 in the smelting process;
s13, adding dolomite when the temperature of the molten steel is 1400 ℃ and the Si content is 0.15-0.4wt%, stirring for 2-3min by side blowing nitrogen, and beginning deslagging.
The above-mentioned chromium stainless steel preparation method, the said AOD decarbonization process includes:
s21, after deslagging is finished, oxygen is blown on the top, oxygen and nitrogen are blown on the side, chromium scrap steel is added, and blowing decarburization is continued;
s22, when the molten steel components meet the steel grade requirements, ferrosilicon, lime and fluorite are added for reduction desulfurization;
s23, tapping after the temperature and the composition of the molten steel meet the requirements.
In the preparation method of the chromium stainless steel, in the step S11, the addition amount of the carbon waste steel is 80-160kg/t, and the addition amount of the lime is 15-30kg/t.
In the above-mentioned method for producing chromium-based stainless steel, in step S11, the strength of the top-blown oxygen gas is 1.0 to 1.2Nm 3 /min.t; the supply amount of the side-blown oxygen and nitrogen is 0.5-0.6Nm 3 /min·t，O：N＝3:1。
In the preparation method of the chromium stainless steel, in the step S12, the adding amount of the carbon steel scrap or the chromium steel scrap of the second tank is 140-200kg/t, and the adding amount of the lime is 15-30kg/t; after stopping top-blowing oxygen, the air supply amount of side blowing is 0.6-0.8Nm 3 /min·t。
In the above-mentioned preparation method of chromium stainless steel, in the step S13, the adding amount of dolomite is 2-4kg/t, and the amount of side-blown nitrogen is 0.65-0.8Nm 3 /min·t。
In the above-mentioned method for producing chromium-based stainless steel, in step S21, the strength of the top-blown oxygen gas is 1.0 to 1.3Nm 3 The supply amount of the side blown oxygen and nitrogen gas is 0.6 Nm.t 3 And (2) per min.t, wherein the adding amount of the chromium scrap steel is 200-280kg/t.
In the preparation method of the chromium stainless steel, in the step S22, the adding amount of the ferrosilicon is 18-25kg/t, the adding amount of the lime is 28-36kg/t, and the adding amount of the fluorite is 6.5-9kg/t.
On the other hand, the chromium stainless steel provided by the invention is prepared by adopting the preparation method of the chromium stainless steel.
The technical scheme of the invention has the following beneficial effects:
(1) According to the preparation method of the chromium stainless steel, desilication, decarbonization and reduction smelting are carried out in the same AOD, and as the converter desilication process is not adopted, the steel tapping temperature drop in the process is reduced, and meanwhile, silicon oxidation heat is fully utilized to melt the scrap steel, so that the addition amount of cold materials in the AOD is increased, and the effective utilization of heat is realized;
(2) The preparation method of the chromium stainless steel can cancel the blast furnace molten iron, reduce dephosphorization procedures and step cost of the blast furnace molten iron, improve the chromium yield, improve the yield from 93.0 percent to more than 95.5 percent by the conventional process, and reduce the smelting cost by 260-300 yuan/t;
(3) The invention provides a method for producing chromium stainless steel by adopting scrap steel and high-carbon ferrochrome to replace molten iron, reduces the process cost and carbon emission of carbon molten iron production of a blast furnace, is a production process route of low-carbon chromium stainless steel, and provides a new method for the development of a low-carbon route of stainless steel.
Detailed Description
The present invention will be described in detail with reference to the following embodiments for a full understanding of the objects, features, and effects of the present invention. The process of the present invention is carried out by methods or apparatus conventional in the art, except as described below. The following terms have the meanings commonly understood by those skilled in the art unless otherwise indicated.
The terms "first," "second," and the like, as used herein do not denote any order or importance, but rather are used to distinguish one element from another, and the terms "the," "a," "an," and "an" do not denote a limitation of quantity, but rather denote the presence of at least one of the referenced item. The terms "preferred," "more preferred," and the like refer to embodiments of the invention that may provide certain benefits in certain circumstances. However, other embodiments may be preferred under the same or other circumstances. Furthermore, the recitation of one or more embodiments does not imply that other embodiments are not useful, nor is it intended to exclude other embodiments from the scope of the invention.
When a range of values is disclosed herein, the range is considered to be continuous and includes both the minimum and maximum values for the range, as well as each value between such minimum and maximum values. Further, when a range refers to an integer, each integer between the minimum and maximum values of the range is included. Further, when multiple range description features or characteristics are provided, the ranges may be combined. In other words, unless otherwise indicated, all ranges disclosed herein are to be understood to include any and all subranges subsumed therein.
Specifically, in order to solve the problems of high silicon content, long desilication time, multiple procedures, low chromium yield and the like of an AOD furnace-entering raw material, the invention provides a preparation method of chromium stainless steel, which comprises the following steps:
s1, melting high-carbon ferrochrome and carbon scrap steel by adopting an intermediate frequency furnace to obtain high-silicon ferrochrome-containing molten iron premelt;
s2, adding the high-silicon chromium-containing molten iron premelting solution into an AOD, and sequentially carrying out an AOD desilication procedure, a deslagging procedure, an AOD decarburization procedure and a deslagging procedure to obtain first molten steel;
s3, transferring the first molten steel into an LF furnace for refining to obtain second molten steel;
and S4, continuously casting the second molten steel to obtain a chromium stainless steel slab.
According to the preparation method of the chromium stainless steel, the desilication and deslagging of the AOD furnace are directly carried out, so that the desilication process of the converter is reduced, the whole smelting process is completed in one container, the thermal efficiency is improved, the process flow is simplified, and the process cost is reduced.
In some preferred embodiments, the high carbon ferrochrome has a Cr content of 48-52wt%, a Si content of 4.5-6.5wt%, and a C content of 6-8wt%; in the high-silicon chromium-containing molten iron premelt, the content of Cr is 20-26wt%, the content of Si is 2.0-3.5wt% and the content of C is 3-5wt%.
The invention uses low-cost high-carbon ferrochrome with high silicon content in the intermediate frequency furnace, so that the silicon content of AOD charging into the furnace is 2.0-3.5%, and the carbon content is 3.0-5.0%, and the step cost is reduced by fully utilizing C, si element oxidation heat release to melt the scrap steel, thereby realizing low-cost smelting of chromium stainless steel.
Preferably, the weight of the high-silicon chromium-containing molten iron premelt is 50-70% of the final tapping amount.
In some preferred embodiments, the AOD desilication process comprises:
s11, adding the high-silicon chromium-containing molten iron premelt into an AOD furnace, adding carbon steel scraps and lime, then top-blowing oxygen, side-blowing oxygen and nitrogen, and converting for 5-8min.
Preferably, 10kg/t lime is added to the bottom of the AOD before adding the high silicon chromium-containing molten iron premelt in the AOD furnace, thereby reducing impact erosion to the bottom of the furnace during molten iron adding and promoting early slag formation.
Preferably, the addition amount of the carbon steel scraps is 80-160kg/t, and the addition amount of the lime is 15-30kg/t.
Preferably, the strength of the top-blown oxygen is 1.0-1.2Nm 3 /min.t; the supply amount of the side-blown oxygen and nitrogen is 0.5-0.6Nm 3 And (2) in the process of (1), the total flow of the top gun and the ratio of the flow of the side gun to oxygen and nitrogen are reasonably controlled, so that efficient desilication is promoted, and the desilication time is shortened.
S12, adding carbon steel scraps or chromium steel scraps in a second tank, adding lime, converting for 10-12min, stopping top blowing oxygen, gradually reducing the proportion of side blowing oxygen, and controlling the slag alkalinity to be 1.2-1.4 in the smelting process.
In the AOD desilication process, the temperature of the desilication process is controlled in a low temperature area (1350-1450 ℃) by adding scrap steel and lime for multiple times, so that chromium oxidation is avoided; by controlling the alkalinity of the slag to be between 1.2 and 1.4, the fluidity of the slag is improved, and the desilication and deslagging time is shortened.
Wherein the addition amount of the AOD cold scrap steel is 30-50% of the tapping amount.
The adding types and the adding amounts of the carbon scrap steel and the chromium scrap steel of the second tank are selected according to the temperature and the component control of molten steel so as to produce different chromium stainless steels. Preferably, the addition amount of the carbon scrap or the chromium scrap of the second tank is 140-200kg/t.
Preferably, the lime is added in an amount of 15-30kg/t.
Preferably, after stopping the top-blowing of oxygen, the side-blowing gas supply amount is 0.6-0.8Nm 3 And (2) gradually adjusting the side-blowing air supply ratio to be O: n=2: 1,O: n=1: 1,O: n=0: 3. by reasonably controlling the top gun flow and the ratio of the side gun flow to oxygen and nitrogen, the high-efficiency desilication is promoted, and the desilication time is shortened.
S13, adding dolomite when the temperature of the molten steel is 1400 ℃ and the Si content is 0.15-0.4wt%, stirring for 2-3min by side blowing nitrogen, and beginning deslagging.
Preferably, the dolomite is added in an amount of 2-4kg/t and the nitrogen side-blown in an amount of 0.65-0.8Nm 3 /min·t。
Preferably, the deslagging speed is fast and then slow, 70-80% of slag is poured out, the furnace is shaken up, and the AOD decarburization operation is continued.
According to the AOD desilication process, zero-carbon scrap steel is adopted, and blast furnace molten iron with high carbon emission is not used, so that carbon emission in the stainless steel production process is reduced.
In some preferred embodiments, the AOD decarbonization process comprises:
and S21, after deslagging, top blowing oxygen, side blowing oxygen and nitrogen, adding chromium scrap steel, and continuing converting and decarburizing.
Preferably, the strength of the top-blown oxygen is 1.0-1.3Nm 3 The supply amount of the side blown oxygen and nitrogen gas is 0.6 Nm.t 3 /min·t。
Preferably, the adding amount of the chromium scrap steel is 200-280kg/t.
S22, when the molten steel components meet the steel grade requirements, ferrosilicon, lime and fluorite are added for reduction desulfurization.
Preferably, the addition amount of the ferrosilicon is 18-25kg/t, the addition amount of the lime is 28-36kg/t, and the addition amount of the fluorite is 6.5-9kg/t.
S23, tapping after the temperature and the composition of the molten steel meet the requirements.
Wherein the temperature and composition of the molten steel are different according to the variety of the chromium-based stainless steel to be smelted, and the invention is not described in detail herein.
Alternatively, the technical parameters of LF refining, continuous casting process, etc. involved in the preparation process of the chromium stainless steel of the present invention may be performed conventionally, which is not particularly limited in the present invention.
On the other hand, the invention also provides chromium stainless steel, which is prepared by adopting the preparation method of the chromium stainless steel.
Wherein the chromium-based stainless steel includes, but is not limited to 430, 410, 420, 409L.
Examples
The invention is further illustrated by means of the following examples, which are not intended to limit the scope of the invention. The experimental methods without specific conditions noted in the following examples follow conventional methods and conditions.
Example 1 180 ton AOD 430 stainless steel production using chromium containing molten iron desilication process
In the embodiment, 180 tons of AOD furnace are adopted to smelt 430 stainless steel (the main components of 430 stainless steel are that C is less than or equal to 0.07wt%, si is less than or equal to 0.75wt%, mn is less than or equal to 1.0wt%, P is less than or equal to 0.040wt%, S is less than or equal to 0.005wt%, and Cr is 16.0-18.0 wt%).
The process route is as follows: the intermediate frequency furnace melts the high-carbon ferrochrome premelt and the intermediate frequency furnace melts the carbon scrap steel, the intermediate frequency furnace premelt is added into the AOD furnace, the AOD desilication is carried out, the AOD inverted desilication slag is carried out, the AOD decarburization smelting, the reduction is carried out, and the LF refining and the continuous casting are carried out.
(1) One medium frequency furnace melts 55 tons of cheap high-carbon ferrochrome (48-52 wt% of Cr, 4.5-6.5wt% of Si and 6-8wt% of C), the other medium frequency furnace melts 55 tons of carbon scrap steel (less than or equal to 0.5wt% of C, less than or equal to 0.5wt% of Si, less than or equal to 2.0wt% of Mn, less than or equal to 0.035wt% of P and the balance iron and impurities), the two medium frequency furnace melts the premelts into the AOD furnace, 2 tons of lime are added in advance into the furnace, the premelt components (Cr: 25wt% of Si:3.0wt% of C:3.5 wt%) and the premelts weight of 110 tons are heated to over 1350 ℃.
(2) Adding high silicon chromium-containing premelt into AOD to perform desilication operation, adding 26 tons of carbon scrap steel, adding 4 tons of lime, and adopting a top lance to supply oxygen with an oxygen supply strength of 260Nm 3 Side-blown oxygen and nitrogen were supplied at 130Nm per minute 3 After converting for 6min, adding 35 tons of chromium scrap steel (C is less than or equal to 0.2wt percent, cr is less than or equal to 13wt percent, P is less than or equal to 0.025wt percent, and the balance is iron), adding 5 tons of lime, converting for 12min, stopping top lance oxygen supply, and side blowing air supply of 150Nm 3 And (3) per min, gradually adjusting the side-blowing gas supply ratio, wherein O is N=2:1, O is N=1:1, O is N=0:3, and controlling the slag alkalinity to be 1.2-1.4 in the smelting process. When the temperature of molten steel is 1400 ℃, si is 0.25-0.4wt%, stopping oxygen supply, adding 600kg of dolomite, stirring by side blowing nitrogen, and the nitrogen amount is 180Nm 3 Stirring for 2-3min, pouring slag at a speed of fast and slow, pouring 80% slag, and shaking up the furnace.
(3) The AOD continues to perform oxygen blowing decarburization, the top lance is adopted to supply oxygen, and the flow rate of the top lance in the decarburization 2 stage is 240Nm 3 Per min, decarburization 3 stage top lance flow 180m 3 Side-blown oxygen and nitrogen were supplied at 130Nm per minute 3 57 tons of chromium scrap steel (C is less than or equal to 0.2wt%, cr is less than or equal to 13wt%, P is less than or equal to 0.025wt%, and the balance is iron) is added for continuous blowing decarburization, when the components reach the steel grade requirement, ferrosilicon, lime and fluorite are added for reduction desulfurization, the addition amount of ferrosilicon is 18-25kg/t, the components are less than or equal to 0.03wt%, si is less than or equal to 0.5wt%, mn is less than or equal to 0.5wt%, P is less than or equal to 0.030wt%, S is less than or equal to 0.005wt%, and Cr is 16.3wt%, and tapping is carried out at proper temperature.
(4) Molten steel enters an LF furnace for refining, and then is hung to a continuous casting process for casting into a plate blank.
The stainless steel 430 produced by the process has the chromium yield of 95.5 percent and the cost is reduced by 300 yuan/t.
EXAMPLE 2 45 ton AOD production of 0Cr13 stainless Steel Using chromium-containing molten iron desilication Process
In the embodiment, a 45 ton AOD furnace is adopted to smelt 0Cr13 stainless steel (the main components of the 0Cr13 stainless steel are that C is less than or equal to 0.06wt%, si is less than or equal to 0.75wt%, mn is less than or equal to 1.0wt%, P is less than or equal to 0.040wt%, S is less than or equal to 0.005wt%, and Cr is 11.5-13.5 wt%).
The process route is as follows: melting high-carbon ferrochrome pre-molten steel and carbon scrap in a 30 ton intermediate frequency furnace, adding the high-carbon ferrochrome pre-molten steel into an AOD furnace, carrying out AOD desilication, carrying out AOD inverted desilication slag, carrying out AOD decarburization smelting, reducing, carrying out LF refining and carrying out continuous casting.
(1) 13 tons of cheap high-carbon ferrochrome (48-52 wt% of Cr, 4.5-6.5wt% of Si and 6-8wt% of C) and 17 tons of carbon scrap steel are melted in an intermediate frequency furnace, and the premelt solution contains 21wt% of Cr, 2.0wt% of Si and 3.0wt% of C, and the premelt solution has a weight of 30 tons and a temperature of over 1350 ℃.
(2) Adding high silicon chromium-containing premelt into AOD to carry out desilication operation, adding 4 tons of carbon scrap steel, adding 1 ton of lime, and controlling the oxygen supply strength to 55Nm 3 Side-blown oxygen and nitrogen were supplied at a supply rate of 28Nm per minute 3 And (3) per minute, wherein O is N=3:1, 6 tons of carbon steel scraps are added after blowing for 5-8 minutes, 1 ton of lime is added, and the slag alkalinity is controlled to be 1.2-1.4 in the smelting process. Molten steel temperature is 1400 ℃, si is 0.15-0.4wt%, 200kg of dolomite is added, nitrogen is blown sideways and stirred, and the nitrogen amount is 38Nm 3 Stirring for 2-3min, pouring slag at a speed of fast and slow, pouring 80% slag, and shaking up the furnace.
(3) The AOD continues to perform oxygen blowing decarburization, the top lance is adopted to supply oxygen, and the flow rate of the top lance in the decarburization 2 stage is 50Nm 3 Per min, decarburization 3 stage top lance flow 38m 3 Side-blown oxygen and nitrogen were supplied at a supply rate of 26Nm per minute 3 And (3) adding 7 tons of carbon scrap steel for continuous blowing decarburization, adding ferrosilicon, lime and fluorite when the components meet the steel grade requirements, carrying out reduction desulfurization, wherein the addition amount of the ferrosilicon is 20-25kg/t, and tapping after the components are at proper temperature. The steel tapping component range is less than or equal to 0.03wt percent, si is less than or equal to 0.5wt percent, mn is less than or equal to 0.5wt percent, P is less than or equal to 0.030wt percent, S is less than or equal to 0.005wt percent, and Cr is 12.8wt percent.
(4) Molten steel enters an LF furnace for refining, and then is hung to a continuous casting process for casting into a plate blank.
The process is adopted to produce 0Cr13 stainless steel, the chromium yield is 95.3%, and the cost is reduced by 260 yuan/t.
The present invention has been disclosed above in terms of preferred embodiments, but it will be understood by those skilled in the art that these embodiments are merely illustrative of the present invention and should not be construed as limiting the scope of the present invention. It should be noted that all changes and substitutions equivalent to those of the embodiments are considered to be covered by the scope of the claims of the present invention. The scope of the invention should, therefore, be determined with reference to the appended claims.
Claims (5)
1. The preparation method of the chromium stainless steel is characterized by comprising the following steps:
s1, melting high-carbon ferrochrome and carbon scrap steel by adopting an intermediate frequency furnace to obtain high-silicon ferrochrome-containing molten iron premelt;
s2, adding the high-silicon chromium-containing molten iron premelting solution into an AOD, and sequentially carrying out an AOD desilication procedure, a deslagging procedure, an AOD decarburization procedure and a deslagging procedure to obtain first molten steel;
s3, transferring the first molten steel into an LF furnace for refining to obtain second molten steel;
s4, continuously casting the second molten steel to obtain a chromium stainless steel slab;
wherein, the AOD desilication procedure includes:
s11, adding the high-silicon chromium-containing molten iron premelt into an AOD furnace, adding 80-160kg/t carbon scrap steel and 15-30kg/t lime according to the proportion of 1.0-1.2Nm 3 Oxygen is blown at the intensity of/min.t according to the ratio of 0.5-0.6Nm 3 Side blowing oxygen and nitrogen in the ratio of/min.t and O: N=3:1, and converting for 5-8min;
s12, adding 140-200kg/t of second tank carbon steel scraps or chromium steel scraps, adding 15-30kg/t of lime, converting for 10-12min, stopping top-blowing oxygen, gradually reducing the proportion of side-blowing oxygen, and controlling the slag alkalinity to be 1.2-1.4 in the smelting process; wherein the air supply amount of the side blowing is 0.6-0.8Nm 3 And (2) per min.t, wherein the proportion of the side-blown oxygen is gradually reduced as follows: n=2: 1,O: n=1: 1,O: n=0: 3, a step of;
s13 when the temperature of the molten steel is 1400 ℃, the Si content is 0.15At-0.4-wt%, adding 2-4kg/t dolomite according to 0.65-0.8Nm 3 Stirring for 2-3min by side blowing nitrogen at the intensity of/min.t, and beginning deslagging.
2. The method for producing a chromium-based stainless steel according to claim 1, wherein said AOD decarburization step comprises:
s21, after deslagging is finished, oxygen is blown on the top, oxygen and nitrogen are blown on the side, chromium scrap steel is added, and blowing decarburization is continued;
s22, when the molten steel components meet the steel grade requirements, ferrosilicon, lime and fluorite are added for reduction desulfurization;
s23, tapping after the temperature and the composition of the molten steel meet the requirements.
3. The method according to claim 2, wherein in step S21, the strength of the top-blown oxygen gas is 1.0 to 1.3. 1.3Nm 3 Per min.t, the supply amount of the side blown oxygen and nitrogen is 0.6. 0.6Nm 3 And/min.t, wherein the adding amount of the chromium scrap steel is 200-280kg/t.
4. The method according to claim 2, wherein in step S22, the amount of the ferrosilicon added is 18-25kg/t, the amount of the lime added is 28-36kg/t, and the amount of the fluorite added is 6.5-9kg/t.
5. A chromium-based stainless steel prepared by the method of any one of claims 1 to 4.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210493593.4A CN114875301B (en) | 2022-05-07 | 2022-05-07 | Chromium stainless steel and preparation method thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210493593.4A CN114875301B (en) | 2022-05-07 | 2022-05-07 | Chromium stainless steel and preparation method thereof |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN114875301A CN114875301A (en) | 2022-08-09 |
| CN114875301B true CN114875301B (en) | 2023-08-11 |
Family
ID=82674046
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202210493593.4A Active CN114875301B (en) | 2022-05-07 | 2022-05-07 | Chromium stainless steel and preparation method thereof |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN114875301B (en) |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102728801A (en) * | 2012-07-12 | 2012-10-17 | 屈志 | Production technology of base stock for stainless steel precision casting |
| CN204265815U (en) * | 2014-11-17 | 2015-04-15 | 中冶南方工程技术有限公司 | Mineral hot furnace and AOD furnace duplex practice stainless steel production system |
| CN108048614A (en) * | 2017-12-08 | 2018-05-18 | 邢台钢铁有限责任公司 | A kind of desiliconization of hot metal, dephosphorization, desulfurization, the method for demanganize pretreatment |
| CN111663071A (en) * | 2020-06-17 | 2020-09-15 | 中冶东方工程技术有限公司 | Economical chromium-manganese stainless steel smelting production method and system thereof |
| CN113737082A (en) * | 2021-08-27 | 2021-12-03 | 中冶赛迪工程技术股份有限公司 | Method for smelting nickel-chromium stainless steel by using high-nickel molten iron for AOD furnace |
-
2022
- 2022-05-07 CN CN202210493593.4A patent/CN114875301B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102728801A (en) * | 2012-07-12 | 2012-10-17 | 屈志 | Production technology of base stock for stainless steel precision casting |
| CN204265815U (en) * | 2014-11-17 | 2015-04-15 | 中冶南方工程技术有限公司 | Mineral hot furnace and AOD furnace duplex practice stainless steel production system |
| CN108048614A (en) * | 2017-12-08 | 2018-05-18 | 邢台钢铁有限责任公司 | A kind of desiliconization of hot metal, dephosphorization, desulfurization, the method for demanganize pretreatment |
| CN111663071A (en) * | 2020-06-17 | 2020-09-15 | 中冶东方工程技术有限公司 | Economical chromium-manganese stainless steel smelting production method and system thereof |
| CN113737082A (en) * | 2021-08-27 | 2021-12-03 | 中冶赛迪工程技术股份有限公司 | Method for smelting nickel-chromium stainless steel by using high-nickel molten iron for AOD furnace |
Also Published As
| Publication number | Publication date |
|---|---|
| CN114875301A (en) | 2022-08-09 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN101993980B (en) | Method for smelting ultralow-phosphorous steel | |
| CN110093479B (en) | Bottom blowing CO2Method for smelting stainless steel | |
| CN113322364B (en) | Low-cost smelting method of ultra-high phosphorus molten iron of steel for polar region | |
| CN112899437A (en) | Oxygen content control method of aluminum-free low-alloy non-oriented silicon steel | |
| CN101381787B (en) | Smelting method of high-alloy steel | |
| CN113737082B (en) | Method for smelting nickel-chromium stainless steel by using high-nickel molten iron for AOD furnace | |
| CN103642966B (en) | Method for improving high-carbon high-manganese steel converter smelting endpoint carbon content and steelmaking method | |
| CN103290299B (en) | Vanadium-titanium nodular cast iron smelting method | |
| CN114875301B (en) | Chromium stainless steel and preparation method thereof | |
| CN114875211B (en) | Method for smelting stainless steel and efficiently desilicating | |
| CN103966387B (en) | Adopt the method for semi-steel making | |
| CN115074606B (en) | Efficient production method of martensitic stainless steel | |
| CN109554515B (en) | Method for smelting stainless steel by top-blown converter | |
| CN113337669B (en) | Method for strengthening electric furnace smelting by bottom blowing hydrogen | |
| CN114657311A (en) | Operation method for directly smelting variety steel by duplex semisteel | |
| JP3460595B2 (en) | Melting method for extremely low sulfur steel | |
| CN111206181B (en) | Smelting method of alloy steel containing phosphorus and copper | |
| CN115369308B (en) | Method for producing high-strength IF steel | |
| CN115652184B (en) | Method for smelting ultra-pure ferrite stainless steel by using slag melting agent in AOD converter | |
| CN115558839B (en) | Production method of P91 steel ingot | |
| CN115354209B (en) | Method for smelting high-manganese high-nitrogen steel 18Cr18Mn12Ni2N by adopting argon-oxygen furnace | |
| CN115595493B (en) | Method for smelting low-phosphorus high-manganese steel based on ferromanganese reduction dephosphorization | |
| CN114790503B (en) | Smelting method with addition of iron ore | |
| CN101070559A (en) | Top-bottom reblowing-converter smelting method for austenite stainless steel | |
| CN113073169A (en) | Method for making steel by using dephosphorized steel slag |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |