CN111363880A - Production method of IF steel for automobile outer plate without inclusion defect - Google Patents
Production method of IF steel for automobile outer plate without inclusion defect Download PDFInfo
- Publication number
- CN111363880A CN111363880A CN202010095551.6A CN202010095551A CN111363880A CN 111363880 A CN111363880 A CN 111363880A CN 202010095551 A CN202010095551 A CN 202010095551A CN 111363880 A CN111363880 A CN 111363880A
- Authority
- CN
- China
- Prior art keywords
- steel
- converter
- equal
- slag
- producing
- 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.)
- Pending
Links
Classifications
-
- 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
- C21C5/30—Regulating or controlling the blowing
- C21C5/35—Blowing from above and through the bath
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
- B22D11/00—Continuous casting of metals, i.e. casting in indefinite lengths
- B22D11/16—Controlling or regulating processes or operations
- B22D11/18—Controlling or regulating processes or operations for pouring
- B22D11/181—Controlling or regulating processes or operations for pouring responsive to molten metal level or slag level
-
- 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
- C21C5/36—Processes yielding slags of special composition
-
- 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
- C21C7/10—Handling in a vacuum
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Manufacturing & Machinery (AREA)
- Mechanical Engineering (AREA)
- Treatment Of Steel In Its Molten State (AREA)
Abstract
The invention discloses a production method of IF steel for an automobile outer plate without inclusion defects, which greatly reduces inclusion defects of the plate by performing key index control on the smelting process of the automobile outer plate and implementing the key index control, and has the advantages of high yield and the like.
Description
Technical Field
The invention relates to the technical field of steel making, in particular to a production method of IF steel for an automobile outer plate without inclusion defects.
Background
The panel material for the automobile is mainly ultra-low carbon deep drawing steel represented by IF steel, and third generation batch drawing steel with excellent deep drawing performance after boiling steel and aluminum killed steel, and is particularly suitable for stamping parts with complex shapes and particularly strict surface quality requirements, namely the plate material is mainly required to have good formability, strength, extensibility, dent resistance, corrosion resistance and the like.
The most basic condition of cold-rolled automobile plates is that the steel quality is required to be pure, but because the automobile outer plates are long in production process and thin in specification, various surface defects such as roll marks, scratches, inclusions, iron scales and the like are easy to appear on the steel-carrying surfaces in the production process. In particular, the smelting and casting of steel grades inevitably entails inclusions, which are mainly present in the form of non-metallic compounds, which may polymerise into clusters or macroscopic inclusion defects, which cause surface inclusion defects that seriously affect the surface appearance and the lacquerability of the automotive sheet.
Therefore, how to develop a production method of IF steel for automobile outer plates to reduce the inclusion defect rate of the IF steel surface becomes a problem to be solved.
Disclosure of Invention
In view of the above, the invention provides a method for producing IF steel for an automobile outer panel without inclusion defects, so as to reduce the inclusion defect rate of the surface of the IF steel.
The invention provides a technical scheme, in particular to a production method of IF steel for an automobile outer plate without inclusion defects, which adopts a combined blown converter for production and specifically comprises the following steps: converter blowing, RH refining, pouring and continuous casting;
wherein, the oxygen content at the blowing end point of the converter is controlled to be 400-600 ppm;
f and O before RH refining are 250-600 ppm, and the oxygen supplement in RH refining process is less than or equal to 30m3The RH net circulation time is more than or equal to 7 min;
the tonnage of the pouring tundish is more than or equal to 30 tons, the argon flow of a water feeding port of the tundish is less than or equal to 5 liters/min in the pouring process, and the superheat degree of the steel ladle is more than or equal to 25 ℃;
the continuous casting drawing speed is a constant drawing speed of 1.1-1.2 m/min.
Preferably, the slag carrying amount of molten steel entering the converter in converter blowing is less than or equal to 20 mm.
More preferably, after the converter blows and taps, the top slag is modified by using the slag modifying material, and the oxidability of the slag is reduced to ∑ Fe which is less than or equal to 7 percent.
Further preferably, the slag discharging amount of the converter is controlled, and the slag thickness before RH refining is ensured to be less than or equal to 70 mm.
More preferably, the standing time is not less than 35min after RH refining and before casting.
Further preferably, the fluctuation range of the liquid level is + -3 mm during casting.
Further preferably, the difference between the final product components and the aluminum after RH refining is less than or equal to 0.009%.
More preferably, the poured tundish molten steel ∑ O is less than or equal to 0.0030 percent.
According to the production method of the IF steel for the automobile outer plate without the inclusion defects, the inclusion defects of the plate are greatly reduced by performing key index control on the smelting process of the automobile outer plate and implementing the key index control, and the method has the advantages of high yield and the like.
It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the disclosure.
Detailed Description
The invention is further explained below with reference to specific embodiments, but is not intended to limit the scope of the invention.
In order to reduce the inclusion defect rate of the surface of IF steel, the embodiment provides a production method of IF steel for an automobile outer plate without inclusion defects, the production method adopts a combined blown converter for production, and the production method specifically comprises the following steps: converter blowing, RH refining, pouring and continuous casting;
wherein, the oxygen content at the blowing end point of the converter is controlled to be 400-600 ppm;
f and O before RH refining are 250-600 ppm, and the oxygen supplement in RH refining process is less than or equal to 30m3The RH net circulation time is more than or equal to 7 min;
the tonnage of the pouring tundish is more than or equal to 30 tons, the argon flow of a water feeding port of the tundish is less than or equal to 5 liters/min in the pouring process, and the superheat degree of the steel ladle is more than or equal to 25 ℃;
the continuous casting drawing speed is a constant drawing speed of 1.1-1.2 m/min.
Wherein the oxygen content at the blowing end point of the converter is controlled to reduce the iron oxide content in the slag, reduce the usage amount of deoxidizing materials in subsequent processes, and reduce the absolute number of deoxidizing products, namely reduce the total content of inclusions.
By controlling the oxygen supplement amount in the RH refining process, the increase of oxides is avoided.
As a further improvement of the technical scheme, the slag carrying amount of molten steel fed into the converter in converter blowing is less than or equal to 20mm, so that smooth converter slagging is ensured, and the control of the end point (alkalinity and oxidizability) of slag is facilitated.
After blowing and tapping of the converter, modifying the top slag by using a slag modifying material, and reducing the oxidability of the slag to ∑ Fe which is less than or equal to 7%, wherein the slag modifying material consists of calcium oxide, aluminum and aluminum oxide.
As a further improvement of the technical scheme, the slag discharging amount of the converter is controlled, and the slag thickness before RH refining is ensured to be less than or equal to 70 mm.
As a further improvement of the technical scheme, the standing time is more than or equal to 35min after RH refining and before casting so as to ensure that impurities in the molten steel float sufficiently.
As a further improvement of the technical scheme, the fluctuation range of the liquid level is +/-3 mm during pouring, so that splashing is avoided.
As a further improvement of the technical scheme, the difference value between the components of the finished product and the aluminum refined by RH is controlled to be less than or equal to 0.009 percent so as to protect casting.
As a further improvement of the technical scheme, the poured tundish molten steel ∑ O is less than or equal to 0.0030 percent.
As an improvement of the optimization, the process control can also be performed from the following aspects to reduce the defect rate:
the steel ladle pouring is not allowed to discharge slag, and the residual steel after pouring is more than or equal to 2t.
And 4, subsequent casting blank cleaning requires four-side cleaning, and the cleaning depth is more than or equal to 3-5 mm.
In order to cooperate with the process parameter control, the management can be strengthened from the following aspects:
1) the complementary blowing and the point blowing of the converter are avoided, and the peroxidation of the molten steel is avoided.
2) Ensuring the self-casting of the ladle in the continuous casting process and preventing the secondary oxidation of molten steel.
3) The temperature rise in the refining process is avoided, and the pollution of the aluminum oxide temperature rise product to molten steel is reduced.
4) The molten steel of the first furnace and the tail blank of the tail furnace of the casting time in the continuous casting process can not be used as production raw materials of the automobile outer plate.
5) The liquid level in the continuous casting pouring process needs to be automatically controlled, and the influence of manual control on the fluctuation and the like of the liquid level of the crystallizer is avoided.
The present invention is further illustrated by the following specific examples, which are not intended to limit the scope of the invention.
Example 1
A production method of IF steel for an automobile outer panel without inclusion defects adopts a combined blown converter for production, and specifically comprises the following steps: converter blowing, RH refining, pouring and continuous casting;
the specific process parameters of each step are controlled as follows:
1) the slag carrying amount of the molten iron entering the converter is less than or equal to 20 mm. Ensuring the smooth operation of converter slagging and being beneficial to controlling the end point (alkalinity and oxidability) of the slag.
2) After converter tapping, the top slag is modified by using a slag modifying material (deoxidation), and the oxidability of the slag is reduced to ∑ Fe which is less than or equal to 7%.
3) The oxygen content at the blowing end point of the converter is controlled to be 400-600 ppm.
4) The slag discharging amount of the converter is controlled, and the slag before RH refining is not more than 70 mm.
5) F.O before refining RH, 250ppm to 600 ppm.
6) The oxygen supplement in the RH process is less than or equal to 30m3。
7) The RH net circulation time is more than or equal to 7 min.
8) The standing time from the refining of the molten steel to the casting (calming) is ensured to be more than or equal to 35 min.
9) The casting tonnage of the tundish is controlled, and the casting tonnage with low tonnage is not allowed to be more than or equal to 30 tons.
10) The steel ladle pouring is not allowed to discharge slag, and the residual steel after pouring is more than or equal to 2t.
11) The fluctuation range of the liquid level is +/-3 mm.
12) Controlling the constant drawing speed of the continuous casting at 1.1-1.2 m/min.
13) The amount of argon at the water feeding port of the tundish in the pouring process is less than or equal to 5 liters/min.
14) The difference between the components of the finished product and the refined aluminum (aluminum burning loss) is less than or equal to 0.009%.
15) The tundish molten steel ∑ O is less than or equal to 0.0030 percent.
16) The superheat degree of the molten steel in the casting process is more than or equal to 25 ℃.
17) And 4, subsequent casting blank cleaning requires four-side cleaning, and the cleaning depth is more than or equal to 3-5 mm.
After the process control in the embodiment 1 is carried out, the yield of the automobile sheet is greatly improved, the inclusion degradation rate of the cold-rolled automobile sheet is reduced from the previous 28.6 percent to no inclusion defect, and a great deal of economic benefit and social effect are created
Other embodiments of the invention will be apparent to those skilled in the art from consideration of the specification and practice of the invention disclosed herein. This application is intended to cover any variations, uses, or adaptations of the invention following, in general, the principles of the invention and including such departures from the present disclosure as come within known or customary practice within the art to which the invention pertains. It is intended that the specification and examples be considered as exemplary only, with a true scope and spirit of the invention being indicated by the following claims.
It is to be understood that the present invention is not limited to what has been described above, and that various modifications and changes may be made without departing from the scope thereof. The scope of the invention is limited only by the appended claims.
Claims (8)
1. A production method of IF steel for an automobile outer panel without inclusion defects is characterized by adopting a combined blown converter for production, and specifically comprises the following steps: converter blowing, RH refining, pouring and continuous casting;
wherein, the oxygen content at the blowing end point of the converter is controlled to be 400-600 ppm;
f and O before RH refining are 250-600 ppm, and the oxygen supplement in RH refining process is less than or equal to 30m3The RH net circulation time is more than or equal to 7 min;
the tonnage of the pouring tundish is more than or equal to 30 tons, the argon flow of a water feeding port of the tundish is less than or equal to 5 liters/min in the pouring process, and the superheat degree of the steel ladle is more than or equal to 25 ℃;
the continuous casting drawing speed is a constant drawing speed of 1.1-1.2 m/min.
2. The method for producing IF steel for an automobile outer panel without inclusion defects as claimed in claim 1, wherein the amount of slag carried in molten steel fed into a converter during converter blowing is 20mm or less.
3. The method for producing IF steel for exterior panels of automobiles, which has no inclusion defects, as claimed in claim 1, wherein after tapping from a converter, the top slag is upgraded with a slag-modifying material to reduce the oxidability of the slag to ∑ Fe.ltoreq.7%.
4. The method for producing IF steel for an automobile outer panel without inclusion defects as claimed in claim 1, wherein the amount of slag discharged from the converter is controlled to ensure that the slag thickness before RH refining is not more than 70 mm.
5. The method for producing IF steel for an automobile outer panel without inclusion defects as claimed in claim 1, wherein the standing time after RH refining until casting is not less than 35 min.
6. The method for producing IF steel for exterior panels of automobiles, which has no inclusion defects, as set forth in claim 1, wherein the fluctuation range of the liquid level at the time of casting is. + -.3 mm.
7. The method for producing IF steel for exterior panels of automobiles, according to claim 1, wherein the difference between the composition of the final product and the aluminum refined in RH is not more than 0.009%.
8. The method for producing IF steel for an automobile outer panel without inclusion defects as claimed in claim 1, wherein ∑ O of the poured tundish molten steel is not more than 0.0030%.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010095551.6A CN111363880A (en) | 2020-02-17 | 2020-02-17 | Production method of IF steel for automobile outer plate without inclusion defect |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010095551.6A CN111363880A (en) | 2020-02-17 | 2020-02-17 | Production method of IF steel for automobile outer plate without inclusion defect |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN111363880A true CN111363880A (en) | 2020-07-03 |
Family
ID=71206265
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202010095551.6A Pending CN111363880A (en) | 2020-02-17 | 2020-02-17 | Production method of IF steel for automobile outer plate without inclusion defect |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN111363880A (en) |
Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101096736A (en) * | 2006-06-27 | 2008-01-02 | 鞍钢股份有限公司 | Clean steel and manufacturing method |
| CN101760583A (en) * | 2009-12-22 | 2010-06-30 | 马鞍山钢铁股份有限公司 | Method for controlling impurity in ultra low carbon IF steel |
| CN102719593A (en) * | 2011-03-29 | 2012-10-10 | 鞍钢股份有限公司 | Method for smelting ultra-low carbon steel |
| CN103233162A (en) * | 2013-05-04 | 2013-08-07 | 河北钢铁股份有限公司唐山分公司 | Process for producing IF steel by using medium sheet billet in continuous casting manner |
| CN106148803A (en) * | 2016-08-30 | 2016-11-23 | 唐山钢铁集团有限责任公司 | A kind of production method of deep-draw battery case steel |
| US20180127845A1 (en) * | 2014-11-12 | 2018-05-10 | Companhia Siderúrgica Nacional | Product that is hot rolled into long steel and use thereof |
| CN109136444A (en) * | 2018-08-30 | 2019-01-04 | 唐山钢铁集团有限责任公司 | Quickly, the new energy car battery shell steel and production method of punch process is thinned |
-
2020
- 2020-02-17 CN CN202010095551.6A patent/CN111363880A/en active Pending
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101096736A (en) * | 2006-06-27 | 2008-01-02 | 鞍钢股份有限公司 | Clean steel and manufacturing method |
| CN101760583A (en) * | 2009-12-22 | 2010-06-30 | 马鞍山钢铁股份有限公司 | Method for controlling impurity in ultra low carbon IF steel |
| CN102719593A (en) * | 2011-03-29 | 2012-10-10 | 鞍钢股份有限公司 | Method for smelting ultra-low carbon steel |
| CN103233162A (en) * | 2013-05-04 | 2013-08-07 | 河北钢铁股份有限公司唐山分公司 | Process for producing IF steel by using medium sheet billet in continuous casting manner |
| US20180127845A1 (en) * | 2014-11-12 | 2018-05-10 | Companhia Siderúrgica Nacional | Product that is hot rolled into long steel and use thereof |
| CN106148803A (en) * | 2016-08-30 | 2016-11-23 | 唐山钢铁集团有限责任公司 | A kind of production method of deep-draw battery case steel |
| CN109136444A (en) * | 2018-08-30 | 2019-01-04 | 唐山钢铁集团有限责任公司 | Quickly, the new energy car battery shell steel and production method of punch process is thinned |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN105463150B (en) | A kind of automobile hub bearing steel smelting technique | |
| CN111057811B (en) | Smelting method of low-cost high-quality steel for hot stamping forming | |
| CN112430707B (en) | Method for improving castability of molten low-carbon aluminum killed steel | |
| CN104789859B (en) | Method for producing peritectic steel by using medium-thin slab continuous caster | |
| CN110527775B (en) | RH refining furnace chemical temperature rising method suitable for low-carbon aluminum killed steel | |
| CN112779458B (en) | Method for controlling inclusions in pipeline steel | |
| CN109402327B (en) | External refining production method of ultrapure high-carbon chromium bearing steel | |
| CN103173588A (en) | RH (relative humidity) treatment method for low silicon-aluminum killed steel | |
| CN104120352A (en) | 34CrMo4 gas cylinder steel and production method thereof | |
| CN110438389B (en) | Production method of high-purity rare earth steel | |
| CN113564308B (en) | Control method for liquid level fluctuation of low-aluminum non-oriented silicon steel crystallizer | |
| CN109877157B (en) | Method for improving flaw detection qualification rate of casting blank finished product 2.25Cr-1Mo steel plate | |
| CN111944940A (en) | Method for controlling inclusions in IF steel | |
| CN109022661B (en) | Method for reducing heavy rail steel rail damage rate | |
| CN112080690A (en) | DC06 automobile plate hot-rolled strip steel and control method for edge warping defect thereof | |
| CN111363880A (en) | Production method of IF steel for automobile outer plate without inclusion defect | |
| CN101476019A (en) | Micro-aluminium silicon-barium-calcium-magnesium composite alloy | |
| CN114535525B (en) | Ultralow-sulfur non-oriented electrical steel and production method thereof | |
| CN113005353B (en) | Method for improving flaw detection qualification rate of 14-30 mm Q345C steel plate | |
| CN104928575A (en) | 355MPa-stage automotive cold forming galvanized hot-rolled substrate and production method thereof | |
| CN115261564A (en) | Non-aluminum deoxidation raw material pure iron for amorphous soft magnetic thin strip and preparation method thereof | |
| CN110846591B (en) | Continuous casting method of rare earth heat-resistant stainless steel | |
| CN114427016A (en) | Production method of aluminum-free bearing steel | |
| CN113817968A (en) | Continuous casting production method for square billet of medium-carbon high-aluminum steel | |
| CN112981250A (en) | Control method for corner crack of low-carbon low-titanium niobium-containing steel sheet billet with low molten iron unit consumption |
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 | ||
| RJ01 | Rejection of invention patent application after publication | ||
| RJ01 | Rejection of invention patent application after publication |
Application publication date: 20200703 |