CN103627951B - High tenacity boracic carbon structural steels coiled sheet and production method thereof - Google Patents

High tenacity boracic carbon structural steels coiled sheet and production method thereof Download PDF

Info

Publication number
CN103627951B
CN103627951B CN201310655113.0A CN201310655113A CN103627951B CN 103627951 B CN103627951 B CN 103627951B CN 201310655113 A CN201310655113 A CN 201310655113A CN 103627951 B CN103627951 B CN 103627951B
Authority
CN
China
Prior art keywords
structural steels
carbon structural
coiled sheet
rolling
high tenacity
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
Application number
CN201310655113.0A
Other languages
Chinese (zh)
Other versions
CN103627951A (en
Inventor
李忠义
朱涛
赵勇
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Magang Group Holding Co Ltd
Maanshan Iron and Steel Co Ltd
Original Assignee
Magang Group Holding Co Ltd
Maanshan Iron and Steel Co Ltd
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Magang Group Holding Co Ltd, Maanshan Iron and Steel Co Ltd filed Critical Magang Group Holding Co Ltd
Priority to CN201310655113.0A priority Critical patent/CN103627951B/en
Publication of CN103627951A publication Critical patent/CN103627951A/en
Application granted granted Critical
Publication of CN103627951B publication Critical patent/CN103627951B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Landscapes

  • Heat Treatment Of Sheet Steel (AREA)
  • Heat Treatment Of Steel (AREA)

Abstract

The present invention relates to a kind of high tenacity boracic carbon structural steels coiled sheet and production method thereof, carbon≤0.30% is contained according to weight, silicon :≤0.50%, manganese :≤1.70%, phosphorus :≤0.035%, sulfur :≤0.035%, aluminum: 0.015~0.050%, and the boron of 8~50ppm, surplus is ferrum and trace impurity.Existing the yield strength 215~345MPa rank carbon structural steels with Q235, SS400 as representative and the extension property of low-alloy steel, room temperature and low-temperature impact toughness is improved by boron micro-alloyed, microstructure homogenization.

Description

High tenacity boracic carbon structural steels coiled sheet and production method thereof
Technical field
The present invention relates to carbon structural steels and low-alloy steel, be specifically related to a kind of high tenacity boracic carbon structural steels coiled sheet and production thereof Method.
Background technology
It is to use general carbon manganese composition design that current each steel mill produces Q235 carbon structural steels coiled sheet.Common problem be 20~25.4mm thickness ranges are easily generated and extend and the problem of strength character deficiency, it is impossible to fully meet the requirement of GB/T700;Right It is that sheet material microscopic structure ' ferrite+a small amount of pearlite ' taeniae telarum occurs in other finger gauge panels or the simultaneous problem of coiled sheet Shape is distributed, and is easily generated stretching fracture layering and impact fracture is layered, and the anisotropy of material property.
Summary of the invention
It is an object of the invention to provide a kind of high tenacity boracic carbon structural steels coiled sheet and production method thereof, pass through boron microalloy Change, microstructure homogenization improves existing the yield strength 215~345MPa rank carbon structural steels with Q235, SS400 as representative Extension property, room temperature and low-temperature impact toughness with low-alloy steel.
Concrete technical scheme is as follows:
High tenacity boracic carbon structural steels coiled sheet, contains carbon≤0.30% according to weight, silicon :≤0.50%, manganese :≤1.70%, Phosphorus :≤0.035%, sulfur :≤0.035%, aluminum: 0.015~0.050%, and the boron of 8~50ppm, surplus is ferrum and trace Impurity.
Further, also include niobium :≤0.050%, and/or, vanadium :≤0.050%, and/or, titanium :≤0.020%, and / or, nickel :≤0.40%, and/or, chromium≤0.50%, and/or, copper :≤0.40%.
The production method of above-mentioned high tenacity boracic carbon structural steels coiled sheet, comprises the steps:
(1) two frame reversable mill roughing are used;
(2) 7 frame hot continuous rollings are carried out;
(3) section cooling after rolling;
(4) batch.
Further, in austenite recrystallization district and Unhydrated cement multi-pass controlled rolling, including:
1180~1220 DEG C of heating;
Breaking down open rolling at 1150~1180 DEG C;
Finish rolling open rolling at 1000 DEG C~950 DEG C;
Finish rolling finish to gauge at 900 DEG C~800 DEG C;
Roll rear section cooling or ultra-rapid cooling;
650 DEG C~500 DEG C terminate cooling and batch.
Further, described cooling uses water curtain section cooling.
Further, water-cooled speed 10 DEG C~50 DEG C/S.
Compared with currently available technology, after the mode of the present invention is improved, add 8~50ppm boron elements, and adjust hot rolling After cooling technological parameter, the mechanical property of more than 20mm think gauge carbon structural steels and low-alloy steel is made to meet GB/T700 Requirement, it is to avoid the generation of drawbacks described above.Simultaneously, it is ensured that coiled sheet is opened after putting down, the parallel and vertical direction along rolling direction The service check result of tensile sample do not decline.Boron element has been widely used for high-strength steel sheet and mild steel strip product In, carbon aluminium-killed steel strip as cold rolling in continuous annealing, very thin hot rolling drawing steel plate, high tensile pipeline steel and non-orientation silicon steel etc.; But the application in carbon structural steels and low-alloy steel is the most rare.Trace B is applied to carbon structural steels and low conjunction by Ma Gang Jin Gangzhong, achieves preferable effect.Make the mechanical property of carbon structural steels including 20.0~25.4mm thickness specifications Not only conform with the requirement of GB/T700, it is to avoid extension property is not enough, strength character is not enough, banded structure and stretching or punching Strike off the generation of the drawbacks described above such as mouth layering, moreover, it is also possible to obtain tough considerably beyond average room temperature and low-temperature impact Property, excellent isotropic performance.
1) process according to the measure of the present invention, make carbon structural steels coiled sheet have good low-temperature impact toughness.
2) processing according to the measure of the present invention, the tissue making carbon structural steels and low-alloy steel coiled sheet is highly uniform, without preferentially taking To, it is layered without fracture.
3), after coiled sheet is opened and put down, vertical mixing coefficient does not declines.
Accompanying drawing explanation
The metallographic structure (with rolling direction vertical direction) of Fig. 1 industrial boracic carbon structural steels
The metallographic structure (along rolling direction parallel direction) of Fig. 2 industrial boracic carbon structural steels
Detailed description of the invention
Describing the present invention below according to accompanying drawing, it is a kind of preferred embodiment in numerous embodiments of the present invention.
Design of Chemical Composition that the present embodiment is used and rolling mill practice, cooling technique be applied to current GB700, JIS G3101, The carbon structural steels of yield strength 200-420MPa of the standard criterions such as JIS G3109 and low-alloy steel, can significantly improve tissue With the uniformity of performance, improve toughness and levels of ductility.
To this end, scheme is characterized by: first, carbon content is less than 0.30%, and the Ultra-low carbon less than 0.06% can be used to design, also Ultra-low carbon design can not be used to use higher than 0.06%, until the carbon content design of the highest 0.30%, still can obtain uniformly Microscopic structure, to avoid banded structure and stretching fracture, the layering of impact fracture;Second, can use interpolation Nb, V, The elements such as Ti carry out microalloying design, it is also possible to do not use the elements such as Nb, V, Ti to carry out microalloying and design to improve surrender Intensity 200-420MPa rank carbon structural steels and the room temperature of low-alloy steel and low-temperature impact toughness;3rd, design rolling, cooling Technique, the method such as comprehensive microalloying, solution strengthening and build up, it is thus achieved that the heterogeneous structure based on acicular ferrite, or Person obtains ' polygonal ferrite+quasi-polygonal ferrite+a small amount of pearlite ' and, to improve intensity, plasticity and extension property, adapts to Need from the diversified performance of 200MPa to 420MPa difference yield strength grade, 25.4mm and following different-thickness hot-rolled sheet coil Ask.
High tenacity boracic carbon structural steels and low-alloy steel coiled sheet Design of Chemical Composition be:
Carbon≤0.30%;Silicon :≤0.50%;Manganese :≤1.70%;Phosphorus :≤0.035%;Sulfur :≤0.035%;Aluminum: 0.015~0.050%;Boron: 8~50ppm.
Require can select to add or can select to be added without following elements according to different properties: niobium :≤0.050%;Vanadium: ≤ 0.050%;Titanium :≤0.020%;Nickel :≤0.40%;Chromium≤0.50%;Copper :≤0.40%.
Ferrum and trace impurity: surplus.
The cooling controlling and rolling controlling process system of high tenacity boracic carbon structural steels and low-alloy steel coiled sheet is:
1. rolling pass distribution: use two frame reversable mill roughing, carry out 7 frame hot continuous rollings, layer after finally rolling again Stream cools down, batches.In austenite recrystallization district and Unhydrated cement multi-pass controlled rolling, (1180~1220 DEG C) heating- (1150~1180) DEG C breaking down open rolling-(1000 DEG C~950 DEG C) finish rolling open rolling-(900 DEG C~800 DEG C) finish rolling finish to gauge-roll Rear section cooling or ultra-rapid cooling-(650 DEG C~500 DEG C) terminate cooling and batch.
2. the type of cooling: water curtain section cooling, water-cooled 10 DEG C~50 DEG C/S.
The foundation of the TMCP process system of high tenacity boracic carbon structural steels and low-alloy steel coiled sheet is:
Thermo-mechanical rolling (TMCP) is based on the metallurgical technology such as recrystallization, phase transformation, makes as-rolled condition plate property reach Goodization.For economizing on resources, reduce the addition of alloying element, optimize carbon structural steels and low-alloy steel coiled sheet microscopic structure, keep away Exempt from banded structure, fracture lamination defect, it is thus achieved that high-caliber toughness, and intensity and the Proper Match of toughness, the present invention is abundant Play rolling power and the roller repairing ability of seven frame hot tandem, and combine with boron micro-alloyed design, pass through high temperature Austenitic area Deformation recrystallization, the deformation of low temperature austenite Unhydrated cement and the cooling of the acceleration after rolling obtain expection and optimize aobvious Micro-assembly robot and the target of mechanical property.
Trace B has segregation effect on austenite grain boundary, can suppress ferritic forming core, make C curve move to right, suppression pearlite Change.Its mechanism of action is: (1) boron segregation, at austenite grain boundary, reduces crystal boundary energy and decreases the position of the preferential forming core of ferrite Put.(2) boron reduces ferrum self-propagating coefficient on crystal boundary, reduces ferritic core forming speed.(3) boron segregation is after crystal boundary, Occupy the position of preferential forming core.(4) form tiny boride and, adhesion coherent with matrix along crystal boundary, make ferrite be difficult to Forming core on interface between boride and matrix.
Boron element has been widely used in high-strength steel sheet and mild steel strip product, and carbon aluminium-killed steel as cold rolling in continuous annealing is thin Band, very thin hot rolling drawing steel plate, high tensile pipeline steel and non-orientation silicon steel etc.;But answering in carbon structural steels and low-alloy steel With the most rare.Trace B is applied in carbon structural steels and low-alloy steel by patent of the present invention, when using acicular ferrite structure Or ' polygonal ferrite+quasi-polygonal ferrite+a small amount of pearlite ', and it is common to make crystal grain refinement can compare with structural homogenity The high tenacity boracic carbon structural steels being not added with boron element and low-alloy steel coiled sheet or opening plate performance more excellent, the extensibility of material Energy, room temperature and low-temperature impact toughness, microscopic structure banding degree all achieve comprehensively improvement.
In preferred embodiment, chemical composition is as shown in table 1.Compare with common SS400, add the boron element of 15~25ppm.
The chemical composition (smelting component) of table 1 SS400 requires (%)
The major parameter of hot rolling technology is as shown in table 2.
Temperature parameter scheme manufactured experimently by table 2
Trial-production temperature parameter Trial-production design
Tapping temperature 1200℃
Finish rolling F1 entrance target temperature FET≤1050℃
Intermediate blank target thickness 60mm
Finishing temperature 880±15℃
Coiling temperature 620±15℃
After production testing, the mechanical property of coiled sheet is as shown in table 3.Corresponding to coiled sheet opening plate mechanical property as shown in table 4, Impact property is as shown in table 5.
The vertical mixing coefficient of table 3 SS400 hot rolled coil
The vertical mixing coefficient of table 4 SS400 opening plate
The impact property of table 5 SS400 opening plate
Above in conjunction with accompanying drawing, the present invention is exemplarily described, it is clear that the present invention implements and is not subject to the restrictions described above, As long as have employed method design and the various improvement that carry out of technical scheme of the present invention, or the most improved directly apply to other occasion , all within protection scope of the present invention.

Claims (1)

1. the production method of a high tenacity boracic carbon structural steels coiled sheet, it is characterised in that comprise the steps:
(1) two frame reversable mill roughing are used;
(2) 7 frame hot continuous rollings are carried out, in austenite recrystallization district and Unhydrated cement multi-pass controlled rolling, including:
Tapping temperature 1200 DEG C;Finish rolling F1 entrance target temperature FET≤1050 DEG C;Intermediate blank target thickness 60mm;Finishing temperature 880 ± 15 DEG C;
(3) water curtain section cooling after rolling, water-cooled speed 10 DEG C~50 DEG C/S;
(4) 620 ± 15 DEG C terminate cooling and also batch, and gained high tenacity boracic carbon structural steels coiled sheet is according to weight carbon containing: 0.12 ~ 0.2%, silicon: 0.2 ~ 0.5%, manganese: 0.4 ~ 0.8%, phosphorus :≤0.030%, sulfur :≤0.030%, aluminum: 0.015~ 0.045%, the boron of nitrogen :≤80ppm and 12~25ppm, surplus is ferrum and trace impurity.
CN201310655113.0A 2013-12-06 2013-12-06 High tenacity boracic carbon structural steels coiled sheet and production method thereof Active CN103627951B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201310655113.0A CN103627951B (en) 2013-12-06 2013-12-06 High tenacity boracic carbon structural steels coiled sheet and production method thereof

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201310655113.0A CN103627951B (en) 2013-12-06 2013-12-06 High tenacity boracic carbon structural steels coiled sheet and production method thereof

Publications (2)

Publication Number Publication Date
CN103627951A CN103627951A (en) 2014-03-12
CN103627951B true CN103627951B (en) 2016-12-07

Family

ID=50209395

Family Applications (1)

Application Number Title Priority Date Filing Date
CN201310655113.0A Active CN103627951B (en) 2013-12-06 2013-12-06 High tenacity boracic carbon structural steels coiled sheet and production method thereof

Country Status (1)

Country Link
CN (1) CN103627951B (en)

Families Citing this family (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103966502B (en) * 2014-05-15 2016-04-13 河北钢铁股份有限公司唐山分公司 Low cost yield strength 400MPa level steel band and production method thereof
CN105779888B (en) * 2016-03-14 2017-09-29 攀钢集团攀枝花钢铁研究院有限公司 A kind of hot rolling production method of carbon structural steels
CN105543708A (en) * 2016-03-14 2016-05-04 攀钢集团攀枝花钢铁研究院有限公司 Carbon structural steel and smelting method thereof
CN105734422B (en) * 2016-03-24 2018-06-05 攀钢集团攀枝花钢铁研究院有限公司 The production method of the effective hot rolled strip of cold rolling thin-walled
CN105803310B (en) * 2016-03-24 2017-10-24 攀钢集团攀枝花钢铁研究院有限公司 A kind of cold rolling light-wall pipe hot rolled strip and its smelting process
CN106011633B (en) * 2016-07-21 2018-01-26 攀钢集团攀枝花钢铁研究院有限公司 A kind of Q235 levels anti-seismic structure hot rolled strip and preparation method thereof
CN109706404B (en) * 2019-02-27 2020-06-23 山东钢铁股份有限公司 Titanium-containing carbon steel and production method thereof
CN111270140A (en) * 2020-03-12 2020-06-12 本钢板材股份有限公司 Production method for improving transverse crease defect of Q235B hot-rolled steel coil
CN116334486A (en) * 2023-03-22 2023-06-27 包头钢铁(集团)有限责任公司 High-strength hot-rolled steel strip with excellent low-temperature impact toughness for automobile and manufacturing method thereof

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102021495A (en) * 2010-12-16 2011-04-20 马鞍山钢铁股份有限公司 420 MPa weatherproof bridge steel with high ductility and method for manufacturing hot rolled coil of 420 MPa weatherproof bridge steel with high ductility
CN102041443A (en) * 2010-12-21 2011-05-04 南阳汉冶特钢有限公司 Low-alloy Q345D-Z25 medium plate and production process thereof
CN102899553A (en) * 2012-09-12 2013-01-30 首钢总公司 Novel boron-containing hot rolled coil and production method thereof

Also Published As

Publication number Publication date
CN103627951A (en) 2014-03-12

Similar Documents

Publication Publication Date Title
CN103627951B (en) High tenacity boracic carbon structural steels coiled sheet and production method thereof
CN100516269C (en) Manufacturing process of fine crystal strengthened carbon constructional steel hot-rolling thin slab
CN104532126B (en) A kind of super high strength hot rolled Q&P steel of low yield strength ratio and its manufacture method
CN102822371B (en) Steel sheet with high tensile strength and superior ductility and method for producing same
CN103080357B (en) High-strength cold-rolled steel sheet having excellent stretch flange properties, and process for production thereof
US20160017449A1 (en) 700MPA-Level High-Strength Hot Rolling Q&P Steel And Method Of Manufacturing The Same
CN108950406B (en) 1000 MPa-grade low-manganese double-partition cold-rolled steel sheet and preparation method thereof
CN106256918B (en) A kind of the Automobile flywheel cold-strip steel and its manufacturing method of precision stamping processing
CN101717886A (en) Hot-rolled dual-phase steel plate with 650 MPa-level tensile strength and manufacturing method thereof
CN103038381A (en) Steel sheet, and process for production thereof
CN102581008A (en) Processing method for producing low-cost high-formability IF (interstitial-free) steel
CN107419078A (en) Yield strength 345MPa level low cost hot rolled steel plates and its manufacture method
CN106435406B (en) A kind of Millettia pachycarpa weather-resistant steel plate and its manufacturing method
CN105177422B (en) Ultra-long thin EH36 steel and production method of ultra-long thin EH36 steel on steckle mill
CN104928580A (en) Low-Mn hot rolled steel and preparation method thereof
CN107012398B (en) A kind of Nb-microalloying TRIP steel and preparation method thereof
CN106191682B (en) A kind of easy-open end draw ring cold rolling hot-dip galvanized steel sheet and its production method
CN107916363A (en) A kind of yield strength 550MPa grades of cold-rolled steel sheets and its manufacture method
CN104419877A (en) Cold-rolled martensitic steel with weather resistance and manufacturing method thereof
CN105695870A (en) thick hot rolled sheet steel with 450MPa grade yield strength and manufacturing method thereof
CN101906519A (en) Method for manufacturing low yield ratio surface layer ultra-fine grain low carbon steel thick plate
CN106498296A (en) Manufacturing method of high-strength steel with yield strength of 1100MPa
CN104451379A (en) High-strength low-alloy niobium-vanadium structural steel and preparation method thereof
CN104018063B (en) The production method of low-alloy high-strength Q420C medium plates
CN102191430A (en) Easy welding steel plate with yield strength of 550MPa and high toughness and manufacturing method thereof

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
C10 Entry into substantive examination
SE01 Entry into force of request for substantive examination
C14 Grant of patent or utility model
GR01 Patent grant