CN102296230A - Hot rolled steel for vehicle wheel steel ring, and production process thereof - Google Patents
Hot rolled steel for vehicle wheel steel ring, and production process thereof Download PDFInfo
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- CN102296230A CN102296230A CN 201110263972 CN201110263972A CN102296230A CN 102296230 A CN102296230 A CN 102296230A CN 201110263972 CN201110263972 CN 201110263972 CN 201110263972 A CN201110263972 A CN 201110263972A CN 102296230 A CN102296230 A CN 102296230A
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Abstract
The invention provides hot rolled steel for a vehicle wheel steel ring, which comprises the following chemical components in percent by weight: 0.06-0.12 percent of C, not more than 0.10 percent of Si, 0.30-0.70 percent of Mn, not more than 0.030 percent of P, not more than 0.020 percent of S and 0.010-0.060 percent of Al. A production process of the hot rolled steel comprises the steps of: LF (Low Frequency) external refining on molten steel meeting the requirement of the chemical components and being obtained through smelting, slab continuous casting, heating of a step type heating furnace, continuous casting of a 2032mm hot continuous casting unit, laminar flow cooling, coiling, checking, storing and delivering. The hot rolled steel for the vehicle wheel steel ring is suitable for cold machining forming, and meets the demands on the cold machining forming.
Description
Technical field
The present invention relates to be used for the production technique of automotive wheel steel ring with hot-rolled steel and this hot-rolled steel.
Background technology
Along with the fast development of Chinese national economy, the demand of automobile constantly increases, and according to the data introduction, the throughput of China's automobile in 2010 reaches 1,800 ten thousand, and meanwhile, automotive industry is also increasing to the demand of vehicle structure steel.The past automaker is when making the automotive wheel steel ring, the structure iron of selecting for use mostly is Q195, Q235, SS400 steel etc. greatly, because serious cracking phenomena often appears in this class steel in the cold deformation process of complexity, cause material use efficiency not high, have a strong impact on the quality and the good looking appearance of car body, so manufacturers is not adopted the hot stamping distortion,, but also bring the increase of processing apparatus (process furnace) and the increase of energy consumption simultaneously with raising material use efficiency and quality product.Therefore be badly in need of a kind of alternate novel material, solved the mass defect that above-mentioned steel grade exists, satisfy the requirements at the higher level that the automobile making material is proposed.
Summary of the invention
At the correlation technique problem of prior art, the object of the present invention is to provide a kind of automotive wheel steel ring that is applicable to cold machine-shaping with hot-rolled steel and production technique thereof, to satisfy the automotive wheel steel ring with the needs of hot-rolled steel sheet to cold machine-shaping.
For achieving the above object, the invention provides a kind of automotive wheel steel ring hot-rolled steel, the chemical ingredients of hot-rolled steel comprises by weight percentage: C:0.06～0.12%, Si :≤0.10%, Mn:0.30～0.70%, P: S≤0.030%: Al:0.010～0.060%≤0.020%.
On the other hand, the present invention also provides a kind of hot-rolled steel production technique, comprise: to satisfying of smelt the obtaining molten steel that the above-mentioned chemical ingredients of the present invention requires carry out LF external refining → sheet billet continuous casting → walking beam furnace heating → 2032mm hot continuous rolling unit rolling → laminar flow cools off → batches → check → put in storage, wherein, the molten steel that satisfies above-mentioned chemical ingredients requirement is to carry out converter smelting to obtain in 150 tons of oxygen top and bottom combined blown converters, in converter steelmaking process: the molten iron that pack into (1) is 132～140 tons, the steel scrap of packing into is 20 tons, desulfurizing iron is handled fed to boiler, goes into stove molten iron S weight percent content≤0.005%; (2) when slag making: basicity R:3.0～3.5 of control slag, and by weight percentage the time, adopt the double slag process slag making in the molten iron under the situation of Si 〉=1.0%, otherwise adopt the single slag process slag making; (3) when carrying out terminal point when control: when satisfying following condition, reach the tapping requirement, C in the molten steel≤0.06%, P≤0.020% by weight percentage, wherein, tapping temperature is controlled at 1675～1685 ℃; (4) when tap, during the operation of deoxidation and alloying: adopt two pushing off the slag during tapping, tapping time 〉=200s; In tapping process, add the reductor that comprises ferro-aluminum; When adding reductor, add required alloy when carrying out described alloying control, C:0.07%～0.09%, Si in the molten steel when making by weight percentage :≤0.05%, Mn:0.30%～0.45%, Als: 〉=0.015%, in LF external refining process: (1) carries out slag control: TFe＜1.0%, CaO:43%～48%, MgO:6%～8%, SiO in the slag when making by weight percentage
2: Al 9%～13%,
2O
3: 20%～24%, and basicity R:3.0～4.5 of control slag; (2) after slag making, carry out the molten steel composition fine setting; (3) carrying out calcium behind the fine setting molten steel composition handles: every stove is fed 400～600m calcium iron wire, and the feeding rate-controlling is at 3.5～4.0m/s; (4) after calcium is handled, guarantee molten steel soft blow argon time＞8min, add ladle covering agent before the molten steel departures, with the protection molten steel, and in carrying out described sheet billet continuous casting process: use cracking resistance card base covering slag; Continuous casting secondary cooling system adopts weak cold mode to crack when preventing the slab cast; Middle bag temperature is controlled at 1545 ± 30 ℃, and pulling rate is controlled at 1.15 ± 0.3m/min.
Preferably, sheet billet continuous casting adopts the whole process protection casting process.
Preferably, when rolling, roughing extreme trace time temperature is controlled at 1080 ± 30 ℃, finish rolling temperature out and is controlled at 880 ± 25 ℃; When laminar flow cooled off, laminar flow refrigerative mode was that leading portion is cold soon, when thickness of strips is 7.0～11.0mm, the laminar flow temperature out was controlled at 610 ± 20 ℃～630 ± 20 ℃; The steel band that batches the back acquisition has uniform ferrite crystal grain, and the grain fineness number of described ferrite crystal grain is 9～10 grades.
Preferably, hot-rolled steel is applicable to cold machine-shaping.
Than prior art, beneficial effect of the present invention is:
(1) by LF refining and calcium treatment process, reduces inclusion content of steel significantly;
(2) sheet billet continuous casting adopts cracking resistance line covering slag and two suitable cold water distribution technologies, has reduced the generation of crackle of steel billet effectively;
(3) by appropriate Composition Control and suitable rolling technology, improve steel plate toughness and plasticity index greatly;
(4) user uses hot-rolled steel sheet of the present invention and steel band to replace former conventional steel plates (Q235 etc.), can save furnace apparatus, is directly used in cold stamping and is shaped; And the user can save the input of process furnace, reduces energy total flow significantly.
(5) user uses hot-rolled steel sheet of the present invention and steel band, and the cracking rate of the cold shaping course of processing satisfies its service requirements less than 0.4%.
Embodiment
Table 1 has been listed hot-rolled steel sheet of the present invention and the included chemical ingredients by weight percentage of steel band; Table 2 has been listed the mechanical property that hot-rolled steel sheet and steel band of the present invention reached.
As table 1 illustrate, the invention provides a kind of automotive wheel steel ring hot-rolled steel sheet and steel band, its chemical ingredients comprises by weight percentage: C:0.06～0.12%, Si :≤0.10%, Mn:0.30～0.70%, P: S≤0.030%: Al:0.010～0.060%≤0.020%.
Table 1
As table 2 illustrate, the full following condition of the mechanical property of hot-rolled steel sheet of the present invention and steel band design, that is, and yield strength: 〉=215MPa; Tensile strength: 370～500MPa elongation: 〉=31%; 1800 clod washes, b=25mm:d=1.5a.
Table 2
On the other hand, the present invention also provides a kind of automotive wheel steel ring production technique with hot-rolled steel sheet and steel band, and its operational path is: to smelt satisfying of the obtaining molten steel that above-mentioned chemical ingredients requires carry out LF external refining → sheet billet continuous casting → walking beam furnace heating → 2032mm hot continuous rolling unit rolling → laminar flow cools off → batches → check → put in storage → deliver.
The molten steel that satisfies above-mentioned chemical ingredients requirement carries out converter smelting and obtains in 150 tons of oxygen top and bottom combined blown converters, in converter steelmaking process: pack molten iron and steel scrap in the converter (1), wherein, the molten iron of packing into is 132～140 tons, the steel scrap of packing into is 20 tons, desulfurizing iron is handled fed to boiler, goes into stove molten iron S weight percent content≤0.005%; (2) during slag making, basicity R:3.0～3.5 of control slag, and by weight percentage the time, adopt the double slag process slag making in the molten iron under the situation of Si 〉=1.0%, otherwise adopt the single slag process slag making; (3) when carrying out terminal point when control: when satisfying following condition, reach the tapping requirement, C in the molten steel≤0.06%, P≤0.020% by weight percentage, wherein, tapping temperature is controlled at 1675～1685 ℃; (4) when tap, during the operation of deoxidation and alloying: adopt two pushing off the slag during tapping, tapping time 〉=200s; In tapping process, add the reductor that comprises ferro-aluminum; When adding reductor, add required alloy when carrying out described alloying control, C:0.07%～0.09%, Si in the molten steel when making by weight percentage :≤0.05%, Mn:0.30%～0.45%, sour molten aluminium (Als): 〉=0.015%.Converter smelting also relates to Argon system behind the stove, strict control argon blowing time and argon flow amount.
The present invention adopts the smelting technology of low silicon (Si) when smelting.In converter steelmaking process, for obtaining ladle top slag effect preferably, the measure of taking has: tapping goes to ladle to add a certain amount of (1200～1500kg) pre-molten slag; Tapping process adds a certain amount of (800～1200kg) lime; Add the 150kg refining slag behind the stove again.
In LF external refining process: (1) carries out slag control: TFe＜1.0%, CaO:43%～48%, MgO:6%～8%, SiO in the slag when making by weight percentage
2: Al 9%～13%,
2O
3: 20%～24%, and basicity R:3.0～4.5 of control slag; (2) after slag making, carry out the molten steel composition fine setting; (3) carrying out calcium behind the fine setting molten steel composition handles: every stove is fed 400～600m calcium iron wire, and the feeding rate-controlling is at 3.5～4.0m/s; (4) after calcium is handled, guarantee molten steel soft blow argon time＞8min, add ladle covering agent before the molten steel departures, with the protection molten steel.
In carrying out described sheet billet continuous casting process: use cracking resistance card base covering slag; Continuous casting secondary cooling system adopts weak cold mode to crack when preventing the slab cast; Middle bag temperature is controlled at 1545 ± 30 ℃, and pulling rate is controlled at 1.15 ± 0.3m/min, and wherein sheet billet continuous casting adopts the whole process protection casting process.
When rolling, roughing extreme trace time temperature is controlled at 1080 ± 30 ℃, finish rolling temperature out and is controlled at 880 ± 25 ℃.
When laminar flow cooled off, laminar flow refrigerative mode was that leading portion is cold soon, when thickness of strips is 7.0～11.0mm, the laminar flow temperature out was controlled at 610 ± 20 ℃～630 ± 20 ℃.
The steel band that batches the back acquisition has uniform ferrite crystal grain, and the grain fineness number of described ferrite crystal grain is 9～10 grades.Hot-rolled steel sheet of the present invention and steel band are applicable to cold machine-shaping.
The used equipment of production technique of the present invention comprises: 150 tons of oxygen top and bottom combined blown converters; The LF refining furnace; The RH vacuum refining furnace; The straight arc billet continuous casting machine of R9m; Walking beam furnace; 2032mm hot continuous rolling unit.
To sum up, by LF refining and calcium treatment process, reduce inclusion content of steel significantly; Sheet billet continuous casting adopts cracking resistance line covering slag and two suitable cold water distribution technologies, has reduced the generation of crackle of steel billet effectively; By appropriate Composition Control and suitable rolling technology, improve steel plate toughness and plasticity index greatly; The user uses hot-rolled steel sheet of the present invention and steel band to replace for example conventional steel plates of Q235, can save furnace apparatus, is directly used in cold stamping and is shaped; And the user can save the input of process furnace, reduces energy total flow significantly; The user uses hot-rolled steel sheet of the present invention and steel band, and the cracking rate of the cold shaping course of processing satisfies its service requirements less than 0.4%.
The above is the preferred embodiments of the present invention only, is not limited to the present invention, and for a person skilled in the art, the present invention can have various changes and variation.Within the spirit and principles in the present invention all, any modification of being done, be equal to replacement, improvement etc., all should be included within protection scope of the present invention.
Claims (5)
1. automotive wheel steel ring hot-rolled steel, it is characterized in that the chemical ingredients of described hot-rolled steel comprises by weight percentage: C:0.06～0.12%, Si :≤0.10%, Mn:0.30～0.70%, P: S≤0.030%: Al:0.010～0.060%≤0.020%.
2. the described hot-rolled steel production technique of claim 1 is characterized in that,
Described production technique comprises: to satisfying of smelt the obtaining molten steel that claim 1 chemical ingredients requires carry out LF external refining → sheet billet continuous casting → walking beam furnace heating → 2032mm hot continuous rolling unit rolling → laminar flow cools off → batches → check → put in storage,
Wherein, the molten steel that satisfies the requirement of claim 1 chemical ingredients is to carry out converter smelting to obtain in 150 tons of oxygen top and bottom combined blown converters, in converter steelmaking process:
(1) work as when filling with substance: the molten iron of packing into is 132～140 tons, and the steel scrap of packing into is 20 tons, and desulfurizing iron is handled fed to boiler, goes into stove molten iron S weight percent content≤0.005%;
(2) when slag making: basicity R:3.0～3.5 of control slag, and by weight percentage the time, adopt the double slag process slag making in the molten iron under the situation of Si 〉=1.0%, otherwise adopt the single slag process slag making;
(3) when carrying out terminal point when control: when satisfying following condition, reach the tapping requirement, C in the molten steel≤0.06%, P≤0.020% by weight percentage, wherein, tapping temperature is controlled at 1675～1685 ℃;
(4) when tap, during the operation of deoxidation and alloying: adopt two pushing off the slag during tapping, tapping time 〉=200s; In tapping process, add the reductor that comprises ferro-aluminum; When adding reductor, add required alloy when carrying out described alloying control, C:0.07%～0.09%, Si in the molten steel when making by weight percentage :≤0.05%, Mn:0.30%～0.45%, Als: 〉=0.015%,
In LF external refining process:
(1) carries out slag control: TFe＜1.0%, CaO:43%～48%, MgO:6%～8%, SiO in the slag when making by weight percentage
2: Al 9%～13%,
2O
3: 20%～24%, and basicity R:3.0～4.5 of control slag;
(2) after slag making, carry out the molten steel composition fine setting;
(3) carrying out calcium behind the fine setting molten steel composition handles: every stove is fed 400～600m calcium iron wire, and the feeding rate-controlling is at 3.5～4.0m/s;
(4) after calcium is handled, guarantee molten steel soft blow argon time＞8min, add ladle covering agent before the molten steel departures, with the protection molten steel,
In carrying out described sheet billet continuous casting process:
Use cracking resistance card base covering slag; Continuous casting secondary cooling system adopts weak cold mode to crack when preventing the slab cast; Middle bag temperature is controlled at 1545 ± 30 ℃, and pulling rate is controlled at 1.15 ± 0.3m/min.
3. production technique according to claim 2 is characterized in that, described sheet billet continuous casting adopts the whole process protection casting process.
4. production technique according to claim 3 is characterized in that,
When rolling, roughing extreme trace time temperature is controlled at 1080 ± 30 ℃, finish rolling temperature out and is controlled at 880 ± 25 ℃;
When laminar flow cooled off, laminar flow refrigerative mode was that leading portion is cold soon, when thickness of strips is 7.0～11.0mm, the laminar flow temperature out was controlled at 610 ± 20 ℃～630 ± 20 ℃;
The steel band that batches the back acquisition has uniform ferrite crystal grain, and the grain fineness number of described ferrite crystal grain is 9～10 grades.
5. according to each described production technique among the claim 2-4, it is characterized in that described hot-rolled steel is applicable to cold machine-shaping.
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Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN102747269A (en) * | 2012-05-22 | 2012-10-24 | 内蒙古包钢钢联股份有限公司 | Low-silicon aluminum-containing steel and production method thereof |
| CN104294144A (en) * | 2014-10-10 | 2015-01-21 | 武汉钢铁(集团)公司 | Steel for automobile rim having tensile strength equal to or greater than 380MPa and production method of steel |
| CN108070749A (en) * | 2017-11-15 | 2018-05-25 | 重庆嘉萌鸿业科技有限公司 | A kind of preparation process of high-intensity steel ring |
| CN108118256A (en) * | 2017-12-29 | 2018-06-05 | 吉林建龙钢铁有限责任公司 | A kind of wheel coils of hot-rolled steel and preparation method thereof |
| CN109797336A (en) * | 2019-01-17 | 2019-05-24 | 武汉钢铁有限公司 | The tubeless rim steel and production method of a kind of thickness in 9 ~ 11mm |
| CN109797351A (en) * | 2019-01-17 | 2019-05-24 | 武汉钢铁有限公司 | A kind of cold forming 16mm thickness tubeless rim steel and production method |
| CN114182156A (en) * | 2020-09-14 | 2022-03-15 | 上海梅山钢铁股份有限公司 | Production method of low-aluminum carbon structural molten steel |
| CN114737123A (en) * | 2022-04-19 | 2022-07-12 | 德龙钢铁有限公司 | Method for preventing Q235B casting blank longitudinal section stress crack from generating |
| CN115233083A (en) * | 2022-08-09 | 2022-10-25 | 重庆钢铁股份有限公司 | Production process of hot-rolled thin steel plate SS400 |
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| CN101603146A (en) * | 2009-07-20 | 2009-12-16 | 重庆钢铁(集团)有限责任公司 | Automobile spoke steel and smelting technology |
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Cited By (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102747269A (en) * | 2012-05-22 | 2012-10-24 | 内蒙古包钢钢联股份有限公司 | Low-silicon aluminum-containing steel and production method thereof |
| CN104294144A (en) * | 2014-10-10 | 2015-01-21 | 武汉钢铁(集团)公司 | Steel for automobile rim having tensile strength equal to or greater than 380MPa and production method of steel |
| CN104294144B (en) * | 2014-10-10 | 2017-01-18 | 武汉钢铁(集团)公司 | Steel for automobile rim having tensile strength equal to or greater than 380MPa and production method of steel |
| CN108070749A (en) * | 2017-11-15 | 2018-05-25 | 重庆嘉萌鸿业科技有限公司 | A kind of preparation process of high-intensity steel ring |
| CN108118256A (en) * | 2017-12-29 | 2018-06-05 | 吉林建龙钢铁有限责任公司 | A kind of wheel coils of hot-rolled steel and preparation method thereof |
| CN108118256B (en) * | 2017-12-29 | 2020-02-21 | 吉林建龙钢铁有限责任公司 | Preparation method of hot-rolled steel coil for wheel without LF external refining |
| CN109797336A (en) * | 2019-01-17 | 2019-05-24 | 武汉钢铁有限公司 | The tubeless rim steel and production method of a kind of thickness in 9 ~ 11mm |
| CN109797351A (en) * | 2019-01-17 | 2019-05-24 | 武汉钢铁有限公司 | A kind of cold forming 16mm thickness tubeless rim steel and production method |
| CN114182156A (en) * | 2020-09-14 | 2022-03-15 | 上海梅山钢铁股份有限公司 | Production method of low-aluminum carbon structural molten steel |
| CN114737123A (en) * | 2022-04-19 | 2022-07-12 | 德龙钢铁有限公司 | Method for preventing Q235B casting blank longitudinal section stress crack from generating |
| CN114737123B (en) * | 2022-04-19 | 2023-12-08 | 德龙钢铁有限公司 | Method for preventing Q235B casting blank longitudinal section stress crack |
| CN115233083A (en) * | 2022-08-09 | 2022-10-25 | 重庆钢铁股份有限公司 | Production process of hot-rolled thin steel plate SS400 |
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