CN104313460A - 500MPa-grade cold rolling dual-phase steel and production method thereof - Google Patents
500MPa-grade cold rolling dual-phase steel and production method thereof Download PDFInfo
- Publication number
- CN104313460A CN104313460A CN201410536158.0A CN201410536158A CN104313460A CN 104313460 A CN104313460 A CN 104313460A CN 201410536158 A CN201410536158 A CN 201410536158A CN 104313460 A CN104313460 A CN 104313460A
- Authority
- CN
- China
- Prior art keywords
- steel
- cold
- temperature
- rolling
- dual
- 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
- 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
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D8/00—Modifying the physical properties by deformation combined with, or followed by, heat treatment
- C21D8/02—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips
- C21D8/0205—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips of ferrous alloys
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D8/00—Modifying the physical properties by deformation combined with, or followed by, heat treatment
- C21D8/02—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips
- C21D8/0221—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips characterised by the working steps
- C21D8/0226—Hot rolling
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D8/00—Modifying the physical properties by deformation combined with, or followed by, heat treatment
- C21D8/02—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips
- C21D8/0221—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips characterised by the working steps
- C21D8/0236—Cold rolling
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D8/00—Modifying the physical properties by deformation combined with, or followed by, heat treatment
- C21D8/02—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips
- C21D8/0247—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips characterised by the heat treatment
-
- 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
-
- 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
- C22C38/001—Ferrous alloys, e.g. steel alloys containing N
-
- 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
- C22C38/06—Ferrous alloys, e.g. steel alloys containing aluminium
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Mechanical Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Physics & Mathematics (AREA)
- Thermal Sciences (AREA)
- Crystallography & Structural Chemistry (AREA)
- Heat Treatment Of Sheet Steel (AREA)
Abstract
The invention discloses a 500MPa-grade cold rolling dual-phase steel and a production method thereof. The method comprises the working procedures of hot rolling and cold rolling continuous annealing; the dual-phase steel comprises the following chemical components by mass percent: 0.06-0.09% of C, 0.32-0.39% of Si, 1.40-1.49% of Mn, less than or equal to 0.015% of P, less than or equal to 0.01% of S, 0.020-0.050% of Als, less than or equal to 0.007% of N, 0.0005-0.0015% of B and the balance of Fe. According to the 500MPa-grade cold rolling dual-phase steel, on the basis of the components of C-Si-Mn dual-phase steel, the content of the Si is reduced, the content of Al is properly increased, and the stability of austenite is improved by the Si and the Al; furthermore, the B element is fed into the steel, and the content of the N is reasonably controlled, so that AlN particles are generated by part of acid-soluble aluminum (Als) in the steel, BN is produced by part of B in the steel, and elution is enhanced; and therefore, the production difficulty is reduced, the smelting castability is not influenced, the cost is low, the production continuity is better, and the product quality is stable. According to the method, the alloy element is not fed into the steel, so that the components of the C-Si-Mn serial dual-phase steel can be improved; the cold rolling dual-phase steel with low yield ratio and high elongation can be produced by steelmaking improvement, the hot rolling process and the cold rolling continuous annealing process.
Description
Technical field
The invention belongs to technical field of metallurgical sheet production, especially a kind of 500MPa level cold-rolled biphase steel and production method thereof.
Background technology
At present, the component system mainly C-Si-Mn series of 500MPa level cold-rolled biphase steel is produced, C-Si-Mn-Cr series, C-Si-Mn-Cr-Mo, C-Si-Mn-Nb and C-Al-Mn series etc.The difficult point of producing cold-rolled biphase steel needs to control higher cooling rate when being to anneal, and controls lower final cooling temperature, makes to there is ferrite, martensite two-phase in cold rolling finished product.The Martensite Volume Fraction then formed when cooling rate is comparatively slow or final cooling temperature is higher is not enough, even can not form martensite, cause finished product low cross-intensity, affect quality product.But high speed of cooling and low final cooling temperature higher to equipment requirements.For the C-Si-Mn of common constituent series dual phase steel, its martensitic transformation temperature is generally at about 250 DEG C, and higher to equipment requirements, industrialized mass production exists certain difficulty.
In order to reduce production difficulty, people add the alloying element strengthening stabilization of austenite in steel, as Cr, Mo etc., such as: the Chinese patent application of application number 201010128668.6 provides a kind of automobile cold-rolled dual-phase steel with tensile strength of 500 MPa, and this cold-rolled biphase steel with the addition of Cr.Be conducive to after adding the alloying elements such as r, Mo improving martensitic transformation temperature, improve final cooling temperature, reduce cooling rate, thus reduce the requirement to equipment; But the alloy prices such as Cr, Mo are higher, production cost is higher, causes finished product price higher, is unfavorable for that the marketization of dual phase steel is promoted.In prior art, in order in low cost and favourable production produce 500MPa level dual phase steel, C-Si-Mn component system adds Nb, or increases Al content, with Al for Si.Nb has certain stable effect strengthening stabilization of austenite and crystal grain thinning, but DeGrain.Al has remarkable effect to raising stabilization of austenite, but Al content higher (about 1.0%), thus cause smelting castability significantly to reduce, be unfavorable for continuous seepage; Reducing Al content will cause stabilization of austenite to decline, and increase production control difficulty.
Summary of the invention
The technical problem to be solved in the present invention is to provide a kind of easy production, 500MPa level cold-rolled biphase steel that castability is good; Present invention also offers a kind of production method of 500MPa level cold-rolled biphase steel.
For solving the problems of the technologies described above, the mass percent of chemical composition of the present invention is: C 0.06 ~ 0.09%, Si 0.32 ~ 0.39%, Mn 1.40 ~ 1.49%, P≤0.015%, S≤0.01%, Als 0.020 ~ 0.050%, N≤0.007%, B 0.0005 ~ 0.0015%, surplus is Fe.
The inventive method comprises hot rolling and cold-rolling continuous annealing operation, the mass percent of described dual phase steel chemical composition is: C 0.06 ~ 0.09%, Si 0.32 ~ 0.39%, Mn 1.40 ~ 1.49%, P≤0.015%, S≤0.01%, Als 0.020 ~ 0.050%, N≤0.007%, B 0.0005 ~ 0.0015%, surplus is Fe.
Hot-rolled process described in the inventive method: hot rolling Heating temperature is 1210 ~ 1250 DEG C; Finishing temperature is 830 ~ 870 DEG C; Coiling temperature is 620 ~ 680 DEG C.Described hot-rolled process: finish rolling start rolling temperature is 1020 ~ 1080 DEG C; In course of hot rolling, roughing stay-warm case normally drops into, needless to say warm after roughing terminates.
Cold-rolling continuous annealing operation described in the inventive method: even moving back soaking temperature is 800 ~ 830 DEG C; Rapid cooling end temp is 290 ~ 330 DEG C, and cooling rate is 25 ~ 40 DEG C/s.Described cold-rolling continuous annealing operation: slow cooling final cooling temperature is 650 ~ 700 DEG C; Completion of prescription temperature is 200 ~ 300 DEG C; Belt speed controls between 70 ~ 270m/min; Smooth elongation control is between 0.8 ~ 1.0%.
The beneficial effect adopting technique scheme to produce is: the present invention reduces Si content on the component base of C-Si-Mn dual phase steel, increase appropriate Al content, stabilization of austenite is improved by Si, Al, conservative control N content simultaneously, a part of B and N in steel is combined and forms BN, because BN formation temperature is higher, the BN particle of formation is thick, is reducing the intensity not affecting steel in steel while N content.Dissolved aluminum Als generates AlN particle under lower temperature conditions, forms precipitation strength, because N content is less, more than Als be solid-solubilized in steel to play and improve the effect of unit elongation.Present invention reduces production difficulty, do not affect smelting castability again, cost is low, and continuous production is better, constant product quality.
The inventive method does not add any alloying element, improving the composition of C-Si-Mn series dual phase steel, reduces Si and contain, add Al content, by improving steel-making, hot rolling technology, cold-rolling continuous annealing technique, producing the cold-rolled biphase steel that yield tensile ratio is low, unit elongation is high; Cost is low, and continuous production is better, constant product quality.The inventive method finished product mechanical performance index: yield strength is 320 ~ 350MPa about, and tensile strength is 530 ~ 550MPa about, unit elongation 26 ~ 28%.
Embodiment
Below in conjunction with specific embodiment, the present invention is further detailed explanation.
The final chemical composition of embodiment 1 ~ 10: this 500MPa level cold-rolled biphase steel and the processing condition of production method as described below.
(1) this cold-rolled biphase steel adopts converter smelting, LF refining, continuous casting, hot rolling and cold-rolling continuous annealing operation to be prepared from, and after continuous casting working procedure, the chemical composition of foundry goods is in table 1.
Table 1: foundry goods chemical composition (wt%)
(2) hot-rolled process:
Described hot-rolled process requires low-temperature heat, high-temperature final rolling, high temperature coiling, is conducive to preventing AlN particle back dissolving, obtains thick AlN particle, the precipitating reinforcing effect of REINFORCED Al N.In course of hot rolling, coiling temperature and trimmed size match; Roughing stay-warm case normally drops into; Do not carry out after roughing terminates treating temperature, directly carry out finish rolling; The concrete processing parameter of each embodiment hot-rolled process is in table 2.
Table 2: hot-rolled process parameter
The coiling temperature of present method hot rolling technology is higher, is conducive to reducing hot-rolled finished product intensity, reduces cold rolling mill load, is conducive to controlling cold rolled sheet shape, improves cold-rolled products quality.Be conducive to making AlN particle coarsening simultaneously.
(3) cold-rolling continuous annealing operation:
Described cold-rolling continuous annealing operation, controls soaking temperature, to produce the necessary two-phase structure of dual phase steel; Control rapid cooling cooling rate, the austenite phase transformation product formed when ensureing soaking is martensite; Control rapid cooling final cooling temperature, to ensure the condensate depression of martensitic transformation.
The cold rolling trimmed size of each embodiment is 1300 × 1.4mm, and it is 62.5% that cold rolling draft controls, and belt speed controls to match with product thickness, and smooth unit elongation and thickness match; Belt speed is mated with cooling rate, controls between 70 ~ 270m/min; Concrete annealing process is in table 3.
Table 3: cold-rolling continuous annealing processing parameter
In described cold-rolling continuous annealing operation, 800 ~ 830 DEG C of soaking are conducive to connecting the ferrite moving back in process austenite and the volume fraction about 75% obtaining volume fraction about 25%.Behind slow cooling section, have partial austenitic to change ferrite into, the austenite volume fraction about 5% of transformation, now the ratio of austenite and ferritic volume fraction is about 2:8.After rapid cooling, this remainder austenitic transformation is martensite, forms the necessary martensite of dual phase steel and adds ferrite two-phase structure, Martensite Volume Fraction about 20% in finished product.Si, Al alloy is added by compound, the martensite transformation temperature of the cold-reduced sheet of this patent composition used is 340 DEG C, improve about 90 DEG C than the martensite transformation temperature of the C-Si-Mn dual phase steel that conventional martensitic transition temperature is 250 DEG C, reach reduction production difficulty, ensure the object that continuous batch is produced.In actual production process, rapid cooling temperature is decided to be 300 DEG C, for martensitic transformation provides enough condensate depression, while guarantee martensitic transformation, reaches the object making martenaging martempering, namely ensure that the intensity of finished product, which in turn improve the toughness of steel.
(4) each embodiment products obtained therefrom mechanical property is in table 4.
Table 4: product mechanical property
As shown in Table 4, embodiment 1-10 products obtained therefrom can meet the performance requriements of 500MPa level cold-rolled biphase steel completely.
Claims (6)
1. a 500MPa level cold-rolled biphase steel, it is characterized in that, the mass percent of its chemical composition is: C 0.06 ~ 0.09%, Si 0.32 ~ 0.39%, Mn 1.40 ~ 1.49%, P≤0.015%, S≤0.01%, Als 0.020 ~ 0.050%, N≤0.007%, B 0.0005 ~ 0.0015%, surplus is Fe.
2. the production method of 500MPa level cold-rolled biphase steel according to claim 1, comprise hot rolling and cold-rolling continuous annealing operation, it is characterized in that, the mass percent of described dual phase steel chemical composition is: C 0.06 ~ 0.09%, Si 0.32 ~ 0.39%, Mn 1.40 ~ 1.49%, P≤0.015%, S≤0.01%, Als 0.020 ~ 0.050%, N≤0.007%, B 0.0005 ~ 0.0015%, surplus is Fe.
3. the production method of 500MPa level cold-rolled biphase steel according to claim 2, is characterized in that, described hot-rolled process: hot rolling Heating temperature is 1210 ~ 1250 DEG C; Finishing temperature is 830 ~ 870 DEG C; Coiling temperature is 620 ~ 680 DEG C.
4. the production method of 500MPa level cold-rolled biphase steel according to claim 3, is characterized in that, described hot-rolled process: finish rolling start rolling temperature is 1020 ~ 1080 DEG C; In course of hot rolling, roughing stay-warm case normally drops into, needless to say warm after roughing terminates.
5. the production method of the 500MPa level cold-rolled biphase steel according to claim 2,3 or 4, is characterized in that, described cold-rolling continuous annealing operation: even moving back soaking temperature is 800 ~ 830 DEG C; Rapid cooling end temp is 290 ~ 330 DEG C, and cooling rate is 25 ~ 40 DEG C/s.
6. the production method of 500MPa level cold-rolled biphase steel according to claim 5, is characterized in that, described cold-rolling continuous annealing operation: slow cooling final cooling temperature is 650 ~ 700 DEG C; Completion of prescription temperature is 200 ~ 300 DEG C; Smooth elongation control is between 0.8 ~ 1.0%.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201410536158.0A CN104313460A (en) | 2014-10-13 | 2014-10-13 | 500MPa-grade cold rolling dual-phase steel and production method thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201410536158.0A CN104313460A (en) | 2014-10-13 | 2014-10-13 | 500MPa-grade cold rolling dual-phase steel and production method thereof |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN104313460A true CN104313460A (en) | 2015-01-28 |
Family
ID=52368766
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201410536158.0A Pending CN104313460A (en) | 2014-10-13 | 2014-10-13 | 500MPa-grade cold rolling dual-phase steel and production method thereof |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN104313460A (en) |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105803321A (en) * | 2016-03-23 | 2016-07-27 | 攀钢集团攀枝花钢铁研究院有限公司 | 980 MPa-level vanadium-contained ultrafine grain cold rolled dual-phase steel and preparing method thereof |
| CN105925912A (en) * | 2016-07-11 | 2016-09-07 | 攀钢集团攀枝花钢铁研究院有限公司 | Tensile strength-780 MPa-stage vanadium-contained cold-rolled dual-phase steel and preparation method thereof |
| CN106011644A (en) * | 2016-07-11 | 2016-10-12 | 攀钢集团攀枝花钢铁研究院有限公司 | High-elongation and high-strength cold-rolled steel plate and preparation method thereof |
| CN107099736A (en) * | 2017-06-06 | 2017-08-29 | 武汉钢铁有限公司 | The production method of 500MPa grades of cold-rolled biphase steels |
| CN109136739A (en) * | 2018-06-29 | 2019-01-04 | 唐山钢铁集团有限责任公司 | The control method of dual phase steel cold rolling high strength car sheet paintable energy surface quality |
| CN111172466A (en) * | 2020-03-04 | 2020-05-19 | 马鞍山钢铁股份有限公司 | Plasticity-enhanced cold-rolled dual-phase steel with tensile strength of 590MPa and production method thereof |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101781739A (en) * | 2010-03-18 | 2010-07-21 | 武汉钢铁(集团)公司 | Automobile cold-rolled dual-phase steel with tensile strength of 500 MPa |
| CN102002639A (en) * | 2009-08-31 | 2011-04-06 | 现代Hysco株式会社 | Dual phase steel sheet and method of manufacturing the same |
| CN102758131A (en) * | 2012-06-18 | 2012-10-31 | 河北钢铁股份有限公司邯郸分公司 | Production method of 600MPa grade cold rolling dual-phase steel |
-
2014
- 2014-10-13 CN CN201410536158.0A patent/CN104313460A/en active Pending
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102002639A (en) * | 2009-08-31 | 2011-04-06 | 现代Hysco株式会社 | Dual phase steel sheet and method of manufacturing the same |
| CN101781739A (en) * | 2010-03-18 | 2010-07-21 | 武汉钢铁(集团)公司 | Automobile cold-rolled dual-phase steel with tensile strength of 500 MPa |
| CN102758131A (en) * | 2012-06-18 | 2012-10-31 | 河北钢铁股份有限公司邯郸分公司 | Production method of 600MPa grade cold rolling dual-phase steel |
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105803321A (en) * | 2016-03-23 | 2016-07-27 | 攀钢集团攀枝花钢铁研究院有限公司 | 980 MPa-level vanadium-contained ultrafine grain cold rolled dual-phase steel and preparing method thereof |
| CN105925912A (en) * | 2016-07-11 | 2016-09-07 | 攀钢集团攀枝花钢铁研究院有限公司 | Tensile strength-780 MPa-stage vanadium-contained cold-rolled dual-phase steel and preparation method thereof |
| CN106011644A (en) * | 2016-07-11 | 2016-10-12 | 攀钢集团攀枝花钢铁研究院有限公司 | High-elongation and high-strength cold-rolled steel plate and preparation method thereof |
| CN105925912B (en) * | 2016-07-11 | 2018-01-26 | 攀钢集团攀枝花钢铁研究院有限公司 | Tensile strength 780MPa levels cold-rolled biphase steel containing vanadium and preparation method thereof |
| CN107099736A (en) * | 2017-06-06 | 2017-08-29 | 武汉钢铁有限公司 | The production method of 500MPa grades of cold-rolled biphase steels |
| CN109136739A (en) * | 2018-06-29 | 2019-01-04 | 唐山钢铁集团有限责任公司 | The control method of dual phase steel cold rolling high strength car sheet paintable energy surface quality |
| CN111172466A (en) * | 2020-03-04 | 2020-05-19 | 马鞍山钢铁股份有限公司 | Plasticity-enhanced cold-rolled dual-phase steel with tensile strength of 590MPa and production method thereof |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN102758131B (en) | Production method of 600MPa grade cold rolling dual-phase steel | |
| CN109504900B (en) | Ultrahigh-strength cold-rolled phase-change induced plasticity steel and preparation method thereof | |
| CN104313460A (en) | 500MPa-grade cold rolling dual-phase steel and production method thereof | |
| CN104498821B (en) | Medium-manganese high-strength steel for automobiles and production method thereof | |
| CN106636911B (en) | With the 900MPa grade hot rolled steel sheets and its manufacturing method of sheet billet Direct Rolling | |
| CN105274432A (en) | 600 MPa-grade high-yield-ratio high-plasticity cold-rolled steel plate and manufacturing method thereof | |
| CN109295283A (en) | A kind of method that short annealing prepares 1000MPa grades of high ductile steels | |
| CN104928580A (en) | Low-Mn hot rolled steel and preparation method thereof | |
| CN108018493A (en) | A kind of 1180MPa grades of hot-rolled dual-phase steel and its manufacture method | |
| CN104513927A (en) | High-strength high-rigidity steel plate with tensile strength of 800 MPa and preparation method thereof | |
| CN102199732B (en) | Boron containing steel plate for heat treatment and manufacturing method thereof | |
| CN105925905B (en) | 780MPa grades of hot-rolled dual-phase steels of Nb-Ti systems and its production method | |
| CN112831731A (en) | Online quenching complex phase structure hot-rolled wear-resistant steel and preparation method thereof | |
| CN104561788B (en) | Phosphorus-containing high-strength interstitial-free steel and production method thereof | |
| CN103695771A (en) | 610MPa-tensile-strength hot-rolled high-strength steel sheet and production method thereof | |
| CN106011633A (en) | Hot-rolled steel belt used for Q235-level anti-seismic structure and preparation method of hot-rolled steel belt | |
| CN103667906A (en) | Hot-rolling high-strength steel sheet having tensile strength of 590 MPa grade and production method thereof | |
| CN103014487A (en) | Hot rolling steel plate for automobile girder, and production method thereof | |
| CN102517496A (en) | Hot rolled ferrite/martensite double phase steel and production method thereof | |
| CN103938070A (en) | Steel plate and preparation method thereof | |
| CN108018498A (en) | A kind of 1180MPa grades of hot-rolled ferrite-bainite dual-phase steel and its manufacture method | |
| CN111321342A (en) | One-steel multi-stage cold-rolled low-alloy high-strength steel and manufacturing method thereof | |
| CN102260824A (en) | Hot-rolled steel plate with yield strength of 550 MPa for hot forming and manufacturing method thereof | |
| CN103233169B (en) | The high strength thin specification steel plate that plate shape is excellent and production method thereof | |
| CN104593665A (en) | Method for manufacturing thick hot-rolled dual-phase steel based on CSP (Compact Strip Production) process |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| RJ01 | Rejection of invention patent application after publication |
Application publication date: 20150128 |
|
| RJ01 | Rejection of invention patent application after publication |