CN101497972B - High strength low yield ratio welding structure steel and production method thereof - Google Patents
High strength low yield ratio welding structure steel and production method thereof Download PDFInfo
- Publication number
- CN101497972B CN101497972B CN2009100611061A CN200910061106A CN101497972B CN 101497972 B CN101497972 B CN 101497972B CN 2009100611061 A CN2009100611061 A CN 2009100611061A CN 200910061106 A CN200910061106 A CN 200910061106A CN 101497972 B CN101497972 B CN 101497972B
- Authority
- CN
- China
- Prior art keywords
- percent
- steel
- cooling
- controlled
- temperature
- 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.)
- Expired - Fee Related
Links
- 229910000831 Steel Inorganic materials 0.000 title claims abstract description 95
- 239000010959 steel Substances 0.000 title claims abstract description 95
- 238000003466 welding Methods 0.000 title claims abstract description 40
- 238000004519 manufacturing process Methods 0.000 title claims abstract description 23
- 238000001816 cooling Methods 0.000 claims abstract description 47
- 238000005096 rolling process Methods 0.000 claims abstract description 40
- 229910052748 manganese Inorganic materials 0.000 claims abstract description 21
- 229910052804 chromium Inorganic materials 0.000 claims abstract description 18
- 238000000034 method Methods 0.000 claims abstract description 17
- 238000010583 slow cooling Methods 0.000 claims abstract description 10
- 238000010438 heat treatment Methods 0.000 claims abstract description 9
- 230000035945 sensitivity Effects 0.000 claims abstract description 8
- 239000000126 substance Substances 0.000 claims abstract description 8
- 239000004615 ingredient Substances 0.000 claims description 7
- 238000005496 tempering Methods 0.000 claims description 5
- 229910052799 carbon Inorganic materials 0.000 abstract description 9
- 230000008569 process Effects 0.000 abstract description 5
- 229910000746 Structural steel Inorganic materials 0.000 abstract description 3
- 229910052759 nickel Inorganic materials 0.000 abstract description 2
- 229910052802 copper Inorganic materials 0.000 abstract 1
- 230000007547 defect Effects 0.000 abstract 1
- 239000012535 impurity Substances 0.000 abstract 1
- 229910052750 molybdenum Inorganic materials 0.000 abstract 1
- 229910052758 niobium Inorganic materials 0.000 abstract 1
- 230000002040 relaxant effect Effects 0.000 abstract 1
- 229910052720 vanadium Inorganic materials 0.000 abstract 1
- 229910052726 zirconium Inorganic materials 0.000 abstract 1
- 239000011572 manganese Substances 0.000 description 35
- 229910001566 austenite Inorganic materials 0.000 description 20
- 229910000859 α-Fe Inorganic materials 0.000 description 13
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 11
- 230000000694 effects Effects 0.000 description 10
- 229910000734 martensite Inorganic materials 0.000 description 9
- 230000009466 transformation Effects 0.000 description 7
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 6
- 229910001563 bainite Inorganic materials 0.000 description 5
- 238000005516 engineering process Methods 0.000 description 5
- 238000001556 precipitation Methods 0.000 description 4
- 229910000885 Dual-phase steel Inorganic materials 0.000 description 3
- 150000001875 compounds Chemical class 0.000 description 3
- 239000013078 crystal Substances 0.000 description 3
- 229910052742 iron Inorganic materials 0.000 description 3
- 239000006104 solid solution Substances 0.000 description 3
- 238000005275 alloying Methods 0.000 description 2
- 230000015572 biosynthetic process Effects 0.000 description 2
- 230000008859 change Effects 0.000 description 2
- 230000008878 coupling Effects 0.000 description 2
- 238000010168 coupling process Methods 0.000 description 2
- 238000005859 coupling reaction Methods 0.000 description 2
- 230000007812 deficiency Effects 0.000 description 2
- 230000005764 inhibitory process Effects 0.000 description 2
- 239000000203 mixture Substances 0.000 description 2
- 150000004767 nitrides Chemical class 0.000 description 2
- 230000006641 stabilisation Effects 0.000 description 2
- 238000011105 stabilization Methods 0.000 description 2
- 238000005728 strengthening Methods 0.000 description 2
- 230000007704 transition Effects 0.000 description 2
- 229910000851 Alloy steel Inorganic materials 0.000 description 1
- UCKMPCXJQFINFW-UHFFFAOYSA-N Sulphide Chemical compound [S-2] UCKMPCXJQFINFW-UHFFFAOYSA-N 0.000 description 1
- 230000001133 acceleration Effects 0.000 description 1
- 230000009471 action Effects 0.000 description 1
- 229910045601 alloy Inorganic materials 0.000 description 1
- 239000000956 alloy Substances 0.000 description 1
- 230000002929 anti-fatigue Effects 0.000 description 1
- 238000013459 approach Methods 0.000 description 1
- 238000004140 cleaning Methods 0.000 description 1
- 239000007771 core particle Substances 0.000 description 1
- 230000007797 corrosion Effects 0.000 description 1
- 238000005260 corrosion Methods 0.000 description 1
- 238000013461 design Methods 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 230000008030 elimination Effects 0.000 description 1
- 238000003379 elimination reaction Methods 0.000 description 1
- 230000005496 eutectics Effects 0.000 description 1
- 238000005098 hot rolling Methods 0.000 description 1
- 230000001939 inductive effect Effects 0.000 description 1
- 230000003993 interaction Effects 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 230000007246 mechanism Effects 0.000 description 1
- 238000002844 melting Methods 0.000 description 1
- 230000008018 melting Effects 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 238000003801 milling Methods 0.000 description 1
- 229910001568 polygonal ferrite Inorganic materials 0.000 description 1
- 238000012545 processing Methods 0.000 description 1
- 230000002035 prolonged effect Effects 0.000 description 1
- 238000001953 recrystallisation Methods 0.000 description 1
- 230000009467 reduction Effects 0.000 description 1
- 238000007670 refining Methods 0.000 description 1
- 230000000630 rising effect Effects 0.000 description 1
- 239000013535 sea water Substances 0.000 description 1
- 238000007493 shaping process Methods 0.000 description 1
- 239000000243 solution Substances 0.000 description 1
- 238000005482 strain hardening Methods 0.000 description 1
- 238000012360 testing method Methods 0.000 description 1
- 238000007669 thermal treatment Methods 0.000 description 1
- RMLPZKRPSQVRAB-UHFFFAOYSA-N tris(3-methylphenyl) phosphate Chemical compound CC1=CC=CC(OP(=O)(OC=2C=C(C)C=CC=2)OC=2C=C(C)C=CC=2)=C1 RMLPZKRPSQVRAB-UHFFFAOYSA-N 0.000 description 1
Landscapes
- Heat Treatment Of Steel (AREA)
Abstract
The invention belongs to welded structural steel with high strength and low yield ratio and a production method thereof, aiming at solving the defects that a steel plate or a steel coil with the specification smaller than 25mm can only be produced, the process is long, and the like. The invention adopts the measures that the welded structural steel contains chemical components by weight that: 0.04-0.10 percent of C, 0.60-2.00 percent of Si, 1.50-2.50 percent of Mn, less than or equal to 0.030 percent of P, less than or equal to 0.010 percent of S, 0.20-0.50 percent of Cu, 0.40-0.80 percent ofCr, 0.35-0.80 percent of Ni, 0.0008-0.0030 percent of B, and at least three of the following components: less than or equal to 0.60 percent of Mo, 0.015-0.060 percent of Nb, 0.030-0.120 percent of V,less than or equal to 0.030 percent of Ti, less than or equal to 0.040 percent of Als and less than or equal to 0.010 percent of Zr, and the rest is Fe and unavoidable impurities; and meanwhile, Mn and Cr also need to satisfy the condition that Mn and Cr are equal to 2.20-2.80 percent, and the welding cold crack sensitivity coefficient Pcm is equal to C plus Si/30 plus (Mn plus Cu plus Cr)/20 plus Mo/15 plus Ni/60 plus V/10 plus 5B and is less than or equal to 0.30 percent; the production method comprises the following steps of heating a steel billet, rough rolling, finishing rolling, relaxing and laminar cooling, and the laminar cooling comprises the following steps of slow cooling, quick cooling and natural cooling to room temperature.
Description
Technical field
The present invention relates to low alloy steel and production method thereof, specifically belong to a kind of high strength low yield ratio welding structure steel and production method thereof, it is the Welded Structural Steel and the production method thereof of the heterogeneous structure high strength low yield strength ratio of a kind of low-temperature flexibility and welding property excellence.
Background technology
Traditional welding structure iron yield tensile ratio when intensity improves is also improving constantly.Especially reach 780MPa when above when tensile strength, the yield tensile ratio of steel is generally more than 0.90.Based on security consideration, too high yield tensile ratio has limited the application of these class steel in the engineering structure field.That development in recent years is got up and at home and abroad the automotive industry dual phase steel that obtains comparatively widespread use have lower yield tensile ratio simultaneously high-intensity.Such steel grade is generally taked hot rolling method and heat treating process production.Traditional hot-rolled dual-phase steel is rolling at two-phase region owing to requiring, thereby the rolling pressure of milling train is had relatively high expectations, and only is fit to produce the thin specification steel plate (volume) below the 25mm.And the thermal treatment dual phase steel has prolonged Production Flow Chart owing to need advance the stove processing, has increased production cost.
2004, University of Science ﹠ Technology, Beijing applied for " high tensile strength high toughness low yield ratio bainite steel and production method thereof " patent of invention, and application number is 200410096795.7.This patent of invention adopts the TMCP+RPC+SQ method to produce, and can realize that tensile strength is that the yield tensile ratio of 800MPa grade steel plate reaches below 0.85.But this steel still need carry out intercritical hardening at two-phase region, and the production cycle is longer.
The patent of invention of the U.S. in 1998 " High strength line pipe steel having low yield ratio and excellent inlow temperature toughness ", the patent No. is 5755895, and this patent provides a kind of composition and production technique of superstrength low yield strength ratio pipe line steel.The tensile strength of this steel grade has excellent HAZ toughness and site welding more than 950MPa.This steel adopts low-carbon high-manganese Ni-Mo-Nb alloying and little Ti to handle in the composition design.Tissue is based on the hard soft two-phase structure of M/B and F, and wherein ferritic content is 20～90%.This steel obtains good comprehensive performances by cooling off in the rolling technology of austenite/ferrite two-phase region strictness and acceleration subsequently.It is low that but this steel grade required for finishing temperature, only 650～800 ℃, when finishing temperature during greater than 800 ℃, the grain refining of this steel is insufficient, and tissues needed changes not exclusively, because steel plate (volume) finishing temperature requires lowly,, thereby only be fit to rolling thickness again than the steel plate (volume) that approaches so need big rolling pressure.In embodiment, maximum ga(u)ge only is 25mm.
Summary of the invention
The objective of the invention is to overcome above-mentioned deficiency, provide a kind of not only intensity height, yield tensile ratio to be lower than 0.81, and do not need tempering, the simple a kind of high strength low yield ratio welding structure steel of technology and production method thereof.
Realize the technical measures of above-mentioned purpose:
A kind of high strength low yield ratio welding structure steel, its chemical ingredients and weight percent are: C:0.04～0.10, Si:0.90～2.00, Mn:1.50～2.50, P≤0.030, S≤0.010, Cu:0.20～0.50, Cr:0.40～0.80, Ni:0.35～0.80, B:0.0008～0.0030; And Mo :≤0.60, Nb:0.015～0.060, V:0.030～0.120, at least add three kinds in Ti≤0.030, Als≤0.040, Zr≤0.010, surplus is Fe and inevitably is mingled with, simultaneously, Mn and Cr also must satisfy [%Mn]+[%Cr]=2.20～2.80, welding cold crack sensitivity FACTOR P cm=C+Si/30+ (Mn+Cu+Cr)/20+Mo/15+Ni/60+V/10+5B≤0.30%.
It is: when not adding Mo in the steel, also must satisfy [%Mn]+[%Cr]=2.50～2.80.
The method of the described a kind of high strength low yield ratio welding structure steel of production claim 1, its step:
A) with billet heating temperature to 1150～1210 ℃;
B) carry out roughing, its start rolling temperature is 1120 ℃～1150 ℃, and total draft is 50～70%, and the roughing end temp is controlled at 1000 ℃～1030 ℃;
C) carry out finish rolling, its start rolling temperature is 930～950 ℃, and the finish rolling end temp is controlled at 860 ℃～880 ℃, and last three passages accumulative total draft is controlled at 25～45%;
D) relaxation finishes the back steel plate is carried out the laminar flow cooling: carry out slow cooling earlier, its rate of cooling is controlled to be 5～8 ℃/second, and cooling termination temperature is controlled to be 720 ℃～780 ℃; It is cold to carry out speed again, and rate of cooling is 15～20 ℃/second, and cooling termination temperature is controlled to be 350 ℃～600 ℃; In air, naturally cool to room temperature at last.
It is: the slow cooling temperature is controlled to be 740 ℃～760 ℃.
It is: the cold final temperature of speed is controlled to be 400 ℃～550 ℃.
It is: steel plate carries out stress relief tempering under 470～530 ℃ condition after naturally cooling to room temperature.
The mechanism of each element and effect among the present invention:
The following weight percentage that all refers to.
C content of the present invention is chosen in 0.04～0.10.C mainly is the intensity that forms the martensite of desired number and guarantee steel.When carbon content is lower than 0.04, can makes the armor plate strength deficiency, but can increase martensitic content in the steel, so its C content is defined as 0.04～0.10 when surpassing 0.10.
Si content of the present invention is 0.60～2.00.Si mainly improves the intensity of steel with the solution strengthening form, can enlarge (the two-phase region of α+γ) again, thereby greatly reduce the susceptibility of the performance of steel to temperature, austenitic stability when improving cooling, quicken separating out of polygonal ferrite, widen the temperature range of austenitizing, and solid solution carbon in the ferrite is had " elimination " and cleaning action, simultaneously, promote the increase of ferrite plasticity.The austenite form that forms when it can also change heating, thus after fast cold, obtain equally distributed martensitic stucture.Si can improve the hardening capacity of steel, helps obtaining tiny equally distributed martensite.The Si that is solidly soluted in the ferrite can influence interaction of dislocation, improves work hardening capacity, is increased in the uniform elongation under the given strength level.Simultaneously also be the deoxidant element in the steel, but content can not be higher than 2.00, in order to avoid reduce the toughness and the welding property of steel.
By the relation between alloying element and the performance as can be known, Mn is the stable and carbide forming element of austenite, and the carbon that an amount of Si can quicken in the ferrite spreads in the austenite that does not change as yet, therefore works as a certain amount of Mn and Si and can play the effect that improves stabilization of austenite, inhibition bainite transformation and reduce the bainite transformation temperature range
Mn content of the present invention is chosen in 1.50～2.50.Mn can enlarge the bifurcation district, reduces A
C1And A
C3Carbon content one regularly increases Mn austenite quantity is increased in steel, thereby generates the increase of martensite quantity.Mn slows down ferrite and pearlitic velocity of transformation, increases the Mn amount sometimes to suppress perlitic transformation.Mn can reduce the solid solution carbon in the ferrite, thereby improves the plasticity of steel.
Mn is the stable and carbide forming element of austenite, and the carbon that Si can quicken in the ferrite does not spread in the austenite that changes as yet, therefore can play the effect that improves stabilization of austenite, suppresses bainite transformation and reduction bainite transformation temperature range when a certain amount of Mn and Si are used
P content of the present invention is: P≤0.030, high P content can increase substantially the weathering resistance of steel, and can make the refinement of martensite island.But P can improve ductile-brittle transition temperature strongly, so need strict control.
S of the present invention≤0.010, high S content not only can make steel plate produce notable difference to performance in length and breadth, also reduce the low-temperature flexibility of steel and Z simultaneously to performance.Sulfide inclusion can make the weather resistance of steel also obviously reduce.
Cu can improve the hardening capacity of steel, mainly plays solid solution and precipitation strength effect in steel, also can improve the weather resistance of steel by the suitable proportion of Cu-Cr-Ni simultaneously, helps obtaining good low-temperature flexibility in addition, increases the antifatigue crack propagation ability of steel.Cu content is less than 0.20, and its precipitation strength effect is not obvious; Greater than 0.50, the steel plate welding heat influence area toughness can reduce as the add-on of Cu, and easily produces check crack in steel billet heat-processed.
Cr also is the effective element that improves hardening capacity, and a certain amount of Cr can make steel obtain good weather resistance.Under the situation of the compound interpolation of Cu-Cr-Ni, Cr helps to improve hardening capacity and weather resistance.
Ni can improve hardening capacity, has certain strengthening effect, can also improve the low-temperature flexibility of steel significantly.Base material and welded heat affecting zone low-temperature flexibility are increased substantially.Ni can also effectively stop the hot-short check crack that causes of Cu.Ni can significantly improve the weather resistance of steel, especially sea water corrosion resistant.Its add-on is less than 0.20, and then Ni does not have effect, but too high levels easily causes the steel plate iron scale to be difficult to come off and increases the cost of steel.
B mainly is the hardening capacity that improves steel in the present invention, postpones austenite to ferrite, pearlitic transformation, when B less than 0.0008 the time, will not have due effect, can cause the low-temperature impact work instability but surpass 0.0030, even cause hot-short.
Mo can make ferrite separate out from austenite and increase austenitic stability, pearlitic formation is had the intensive inhibition, but Mo belongs to noble element, and excessive Mo will improve the cost of steel.Too high Mo can make the low-temperature flexibility of steel significantly worsen simultaneously.When welding, form martensite, cause the brittle increase of welding joint.
Nb is strong carboritride forming element, can improve the austenite recrystallization temperature of steel.Austenite can be rolled under higher rolling temperature.The precipitation strength effect of Nb in the controlled rolling continuous cooling process in addition, the strain inducing of the carbonitride by Nb are separated out can the pinning austenite crystal, and refine austenite crystal grain also improves intensity and low-temperature flexibility.Nb sometimes separately or with the compound adding of Ti to improve the mechanical property of steel by precipitation strength.But too high Nb is also easy and elements such as Fe, C form the low melting point eutectic things, thereby increases the tendency that weld metal produces thermal crack.
V also is strong carboritride forming element, when V content is low, can not bring into play the effect of its controlled rolling, and the carbonitride that excessive V can cause rolling back V is obviously separated out, and improves the steel plate yield strength and causes the rising of yield tensile ratio.The present invention is 0.030～0.120.
Therefore Ti is strong nitride forming element, and the nitride of Ti is the pinning austenite grain boundary effectively, helps to control growing up of austenite crystal, the suitable content of Ti is controlled at≤and 0.030.
Steel Als content of the present invention is controlled at≤and 0.040%, Al is the main deoxidant element in the steel.Al content will cause the oxide inclusion of Al to increase greater than 0.035%, reduce the purity of steel, be unfavorable for the toughness and the weather resistance of steel.The fusing point of Al is higher, and aborning, Al can be used for stoping grain growth.
Zr among the present invention≤0.010%, the oxide compound that an amount of Zr forms in pyroprocess can be used as acicular structure forming core particle, forms a large amount of acicular structures at welded heat affecting zone, to improve steel plate Chinese People's Anti-Japanese Military and Political College heat input welding property.
In addition, Mn and Cr also must satisfy: [%Mn]+[%Cr]=2.20～2.80; When not adding Mo in the steel, must [%Mn]+[%Cr]=2.50～2.80.Mn and Cr all can improve the hardening capacity of steel.
The present invention compared with prior art, it is by component and content and technology controlling and process, the formation of its metallographic structure is based on ferrite, the distributing heterogeneous structure of martensite and residual austenite of ferrite intergranular.Wherein the volume fraction of ferrite intergranular martensite and residual austenite is 10～30%.Steel plate has good obdurability coupling, and steel plate has lower yield tensile ratio when having excellent welding property and low-temperature flexibility, and yield tensile ratio is generally 0.66～0.80; Steel plate need not to heat-treat, so the production cycle is shorter, and flow process is simple; By the interpolation of alloy content, improved the stability of supercooled austenite effectively, reduced the Ms point, so that carry out cooling control after rolling.
It is 16～50mm that the present invention can produce steel plate thickness, its tensile strength R
m780～930Mpa, yield tensile ratio R
EL/ R
m≤ 0.80, Cold Brittleness Transition Temperature has excellent welding property and cold machine-shaping below-40 ℃.Can be widely used in engineering structures such as bridge, building, traffic, ocean platform.
Embodiment
Embodiment 1:
A kind of high strength low yield ratio welding structure steel, its chemical ingredients and weight percent are: C:0.04, Si:2.00, Mn:1.80, P:0.030, S:0.010, Cu:0.30, Cr:0.40, Ni:0.45, B:0.0030; And Mo:0.60, Nb:0.015, V:0.030, surplus is Fe and inevitably is mingled with; [%Mn]+[%Cr]=2.20, welding cold crack sensitivity FACTOR P cm=C+Si/30+ (Mn+Cu+Cr)/20+Mo/15+Ni/60+V/10+5B=0.30.
Production method, its step:
1) with billet heating temperature to 1150 ℃;
2) carry out roughing, its start rolling temperature is 1120 ℃, and total draft is 50%, and the roughing end temp is controlled at 1000 ℃;
3) carry out finish rolling, its start rolling temperature is 930 ℃, and the finish rolling end temp is controlled at 860 ℃, and last three passages accumulative total draft is controlled at 25%;
4) relaxation finishes the back steel plate is carried out the laminar flow cooling: carry out slow cooling earlier, its rate of cooling is controlled to be 5 ℃/second, and cooling termination temperature is controlled to be 720 ℃ ℃; It is cold to carry out speed again, and rate of cooling is 15 ℃/second, and cooling termination temperature is controlled to be 350 ℃; In air, naturally cool to room temperature at last.
Embodiment 2:
A kind of high strength low yield ratio welding structure steel, its chemical ingredients and weight percent are: C:0.059, Si:0.90, Mn:2.30, P:0.020, S:0.009, Cu:0.20, Cr:0.50, Ni:0.50, B:0.0008; And Nb:0.045, Ti:0.030, Als:0.020, Zr:0.0080, surplus is Fe and inevitably is mingled with; [%Mn]+[%Cr]=2.80, welding cold crack sensitivity FACTOR P cm=C+Si/30+ (Mn+Cu+Cr)/20+Mo/15+Ni/60+V/10+5B=0.25%.
The method of the described a kind of high strength low yield ratio welding structure steel of production claim 1, its step:
1) with billet heating temperature to 1180 ℃;
2) carry out roughing, its start rolling temperature is 1130 ℃, and total draft is 58%, and the roughing end temp is controlled at 1010 ℃;
3) carry out finish rolling, its start rolling temperature is 945 ℃, and the finish rolling end temp is controlled at 868 ℃, and last three passages accumulative total draft is controlled at 30%;
4) relaxation finishes the back steel plate is carried out the laminar flow cooling: carry out slow cooling earlier, its rate of cooling is controlled to be 6.5 ℃/second, and cooling termination temperature is controlled to be 740 ℃; It is cold to carry out speed again, and rate of cooling is 16.5 ℃/second, and cooling termination temperature is controlled to be 400 ℃; In air, naturally cool to room temperature at last.
In order to eliminate stress, after naturally cooling to room temperature, steel plate under 470 ℃ of conditions, carries out tempering.
Embodiment 3:
A kind of high strength low yield ratio welding structure steel, its chemical ingredients and weight percent are: C:0.07, Si:1.20, Mn:2.00, P:0.010, S:0.006, Cu:0.36, Cr:0.50, Ni:0.35, B:0.001; And Mo:0.10, Nb:0.060, Ti:0.019, Als:0.009, Zr:0.01, surplus is Fe and inevitably is mingled with; [%Mn]+[%Cr]=2.50, welding cold crack sensitivity FACTOR P cm=C+Si/30+ (Mn+Cu+Cr)/20+Mo/15+Ni/60+V/10+5B=0.27%.
The method of the described a kind of high strength low yield ratio welding structure steel of production claim 1, its step:
1) with billet heating temperature to 1180 ℃;
2) carry out roughing, its start rolling temperature is 1130 ℃, and total draft is 58%, and the roughing end temp is controlled at 1010 ℃;
3) carry out finish rolling, its start rolling temperature is 945 ℃, and the finish rolling end temp is controlled at 868 ℃, and last three passages accumulative total draft is controlled at 30%;
4) relaxation finishes the back steel plate is carried out the laminar flow cooling: carry out slow cooling earlier, its rate of cooling is controlled to be 7 ℃/second, and cooling termination temperature is controlled to be 740 ℃; It is cold to carry out speed again, and rate of cooling is 16.5 ℃/second, and cooling termination temperature is controlled to be 400 ℃; In air, naturally cool to room temperature at last.
In order to eliminate stress, after naturally cooling to room temperature, steel plate under 530 ℃ of conditions, carries out tempering.
Embodiment 4:
A kind of high strength low yield ratio welding structure steel, its chemical ingredients and weight percent are: C:0.10, Si:0.60, Mn:1.50, P:0.015, S:0.006, Cu:0.45, Cr:0.80, Ni:0.70, B:0.0018; And Mo:0.12, V:0.12, Ti:0.009, Als:0.04, surplus is Fe and inevitably is mingled with; [%Mn]+[%Cr]=2.30, welding cold crack sensitivity FACTOR P cm=C+Si/30+ (Mn+Cu+Cr)/20+Mo/15+Ni/60+V/10+5B=0.30%.
Produce a kind of method of high strength low yield ratio welding structure steel, its step:
1) with billet heating temperature to 1200 ℃;
2) carry out roughing, its start rolling temperature is 1150 ℃, and total draft is 63%, and the roughing end temp is controlled at 1020 ℃;
3) carry out finish rolling, its start rolling temperature is 950 ℃, and the finish rolling end temp is controlled at 870 ℃, and last three passages accumulative total draft is controlled at 41%;
4) relaxation finishes the back steel plate is carried out the laminar flow cooling: carry out slow cooling earlier, its rate of cooling is controlled to be 8 ℃/second, and cooling termination temperature is controlled to be 760 ℃; It is cold to carry out speed again, and rate of cooling is 18 ℃/second, and cooling termination temperature is controlled to be 550 ℃; In air, naturally cool to room temperature at last.
Embodiment 5:
A kind of high strength low yield ratio welding structure steel, its chemical ingredients and weight percent are: C:0.083, Si:1.00, Mn:2.00, P:0.018, S:0.005, Cu:0.35, Cr:0.50, Ni:0.30, B:0.0012; And Nb:0.035, V:0.100, Ti:0.0085, Als:0.040, Zr:0.002, surplus is Fe and inevitably is mingled with; [%Mn]+[%Cr]=2.50, welding cold crack sensitivity FACTOR P cm=C+Si/30+ (Mn+Cu+Cr)/20+Mo/15+Ni/60+V/10+5B=0.28%.
Produce a kind of method of high strength low yield ratio welding structure steel, its step:
1) with billet heating temperature to 1210 ℃;
2) carry out roughing, its start rolling temperature is 1135 ℃, and total draft is 70%, and the roughing end temp is controlled at 1030 ℃;
3) carry out finish rolling, its start rolling temperature is 945 ℃, and the finish rolling end temp is controlled at 880 ℃, and last three passages accumulative total draft is controlled at 45%;
4) relaxation finishes the back steel plate is carried out the laminar flow cooling: carry out slow cooling earlier, its rate of cooling is controlled to be 6.5 ℃/second, and cooling termination temperature is controlled to be 780 ℃; It is cold to carry out speed again, and rate of cooling is 20 ℃/second, and cooling termination temperature is controlled to be 600 ℃; In air, naturally cool to room temperature at last.
Through test, its result, its yield strength is at 550～700MPa, tensile strength is at 750～900MPa, and yield tensile ratio is 0.66～0.80, and-40 ℃ of ballistic works are at 200～298J, steel plate has good obdurability coupling and excellent welding property and low-temperature flexibility, satisfies customer requirements.
Claims (6)
1. high strength low yield ratio welding structure steel, its chemical ingredients and weight percent are: C:0.04～0.10, Si:0.90～2.00, Mn:1.50～2.50, P≤0.030, S≤0.010, Cu:0.20～0.50, Cr:0.40～0.80, Ni:0.35～0.80, B:0.0008～0.0030; And Mo :≤0.60, Nb:0.015～0.060, V:0.030～0.120, at least add three kinds in Ti≤0.030, Als≤0.040, Zr≤0.010, surplus is Fe and inevitably is mingled with, simultaneously, Mn and Cr also must satisfy [%Mn]+[%Cr]=2.20～2.80, welding cold crack sensitivity FACTOR P cm=C+Si/30+ (Mn+Cu+Cr)/20+Mo/15+Ni/60+V/10+5B≤0.30%.
2. a kind of high strength low yield ratio welding structure steel as claimed in claim 1 is characterized in that: when not adding Mo in the steel, also must satisfy [%Mn]+[%Cr]=2.50～2.80.
3. the method for the described a kind of high strength low yield ratio welding structure steel of production claim 1, its step:
A) with billet heating temperature to 1150～1210 ℃;
B) carry out roughing, its start rolling temperature is 1120 ℃～1150 ℃, and total draft is 50～70%, and the roughing end temp is controlled at 1000 ℃～1030 ℃;
C) carry out finish rolling, its start rolling temperature is 930～950 ℃, and the finish rolling end temp is controlled at 860 ℃～880 ℃, and last three passages accumulative total draft is controlled at 25～45%;
D) relaxation finishes the back steel plate is carried out the laminar flow cooling: carry out slow cooling earlier, its rate of cooling is controlled to be 5～8 ℃/second, and cooling termination temperature is controlled to be 720 ℃～780 ℃; It is cold to carry out speed again, and rate of cooling is 15～20 ℃/second, and cooling termination temperature is controlled to be 350 ℃～600 ℃; In air, naturally cool to room temperature at last.
4. the method for a kind of high strength low yield ratio welding structure steel of production as claimed in claim 3 is characterized in that: the slow cooling temperature is controlled to be 740 ℃～760 ℃.
5. the method for a kind of high strength low yield ratio welding structure steel of production as claimed in claim 3 is characterized in that: the cold final temperature of speed is controlled to be 400 ℃～550 ℃.
6. the method for a kind of high strength low yield ratio welding structure steel of production as claimed in claim 3 is characterized in that: steel plate carries out stress relief tempering under 470～530 ℃ condition after naturally cooling to room temperature.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2009100611061A CN101497972B (en) | 2009-03-13 | 2009-03-13 | High strength low yield ratio welding structure steel and production method thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2009100611061A CN101497972B (en) | 2009-03-13 | 2009-03-13 | High strength low yield ratio welding structure steel and production method thereof |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN101497972A CN101497972A (en) | 2009-08-05 |
| CN101497972B true CN101497972B (en) | 2011-03-23 |
Family
ID=40945242
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN2009100611061A Expired - Fee Related CN101497972B (en) | 2009-03-13 | 2009-03-13 | High strength low yield ratio welding structure steel and production method thereof |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN101497972B (en) |
Families Citing this family (15)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101979166B (en) * | 2010-09-20 | 2012-10-10 | 首钢总公司 | Production method of low-yield-ratio micro-alloy pipeline steel hot-rolled coiled plate |
| CN102851589B (en) * | 2011-06-29 | 2014-06-04 | 宝山钢铁股份有限公司 | Steel for low temperature structure with low yield ratio and capable of performing ultrahigh heat input and manufacture method thereof |
| CN102605154A (en) * | 2012-03-28 | 2012-07-25 | 南京钢铁股份有限公司 | Production process for realizing relaxation or online quenching through even times of rolling on medium plate |
| CN102699029B (en) * | 2012-05-29 | 2014-08-27 | 武汉钢铁(集团)公司 | Manufacturing method for easily pickled steel with low yield ratio by thin slab casting and rolling |
| CN103305767B (en) * | 2013-05-15 | 2015-05-13 | 武汉钢铁(集团)公司 | Steel for engineering machinery with yield strength more than or equal to 750MPa and production method of steel for engineering machinery |
| CN103422025B (en) * | 2013-09-13 | 2015-10-14 | 武汉钢铁(集团)公司 | The low yield strength ratio structural steel of yield strength >=690MPa and production method thereof |
| CN104087839B (en) * | 2014-07-18 | 2016-05-25 | 武汉钢铁(集团)公司 | The ultra-thin laser weld steel for saw blade substrate of hot rolling and production method |
| CN104775078B (en) * | 2015-03-13 | 2017-07-07 | 武汉钢铁(集团)公司 | The low-yield-ratio fire resistant structural steel and production method of a kind of Rel ＞ 620MPa |
| WO2017011751A1 (en) | 2015-07-15 | 2017-01-19 | Ak Stell Properties, Inc. | High formability dual phase steel |
| CN105132805B (en) * | 2015-09-15 | 2017-03-15 | 攀钢集团攀枝花钢铁研究院有限公司 | A kind of steel for welded structures containing vanadium and preparation method thereof |
| CN105296856B (en) * | 2015-11-19 | 2017-06-16 | 国家电网公司 | Extra-high voltage Special electric tower high-strength steel |
| CN107841687B (en) * | 2017-11-15 | 2019-04-19 | 南阳汉冶特钢有限公司 | A kind of smelting process of ultralow boron steel |
| CN112575252A (en) * | 2020-11-19 | 2021-03-30 | 武汉钢铁有限公司 | Economical high-crack-sensitivity high-strength steel plate and preparation method thereof |
| CN113637919A (en) * | 2021-07-23 | 2021-11-12 | 南京钢铁股份有限公司 | High-efficiency low-cost 800 MPa-grade steel plate for hydropower and production method thereof |
| CN114645183B (en) * | 2022-03-26 | 2023-01-03 | 湖南华菱湘潭钢铁有限公司 | Production method of high-toughness low-yield-ratio low-alloy high-strength steel plate |
-
2009
- 2009-03-13 CN CN2009100611061A patent/CN101497972B/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| CN101497972A (en) | 2009-08-05 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN101497972B (en) | High strength low yield ratio welding structure steel and production method thereof | |
| JP5476763B2 (en) | High tensile steel plate with excellent ductility and method for producing the same | |
| CN103422025B (en) | The low yield strength ratio structural steel of yield strength >=690MPa and production method thereof | |
| CN103422021B (en) | Low-yield-ratio structural steel with yield ratio equal to or larger than 550MPa and manufacturing method thereof | |
| CN101407892B (en) | Ultra-low carbon hot rolling weathering steel with yield strength larger than 550MPa | |
| CN102605287B (en) | Steel for high-ductility anti-seismic structure with yield ratio smaller than or equal to 0.70 and production method of steel | |
| JP2016511326A (en) | High corrosion resistance high strength Al-containing weathering steel sheet and method for producing the same | |
| CN1970818A (en) | High-strength weathering steel and method of manufacturing same | |
| CN101497969A (en) | High-performance weather-resisting anti-seismic steel for building and production method thereof | |
| CN104532155B (en) | X90 level heterogeneous structure pipeline steel for longitudinal welded pipe | |
| CN101691643A (en) | Refractory anti-seismic construction steel for high-toughness welding structures, and production method thereof | |
| CN112575158B (en) | High-plasticity thick-specification pipeline steel plate and manufacturing method thereof | |
| CN114134408B (en) | 460 MPa-level bridge steel plate and manufacturing method thereof | |
| CN101775561A (en) | Thick plate with low yield ratio and high strength and its preparation process | |
| CN102699031B (en) | 900 MPa grade ultrahigh-toughness low alloy steel and manufacture method thereof | |
| CN103667909B (en) | A kind of mobile ocean Platform Steel of yield tensile ratio≤0.65 and production method | |
| KR20200066512A (en) | Ultra high strength steel material having excellent cold workability and sulfide stress cracking resistance and method of manufacturing the same | |
| US20060016526A1 (en) | High-strength steel for welded structures excellent in high temperature strength and method of production of the same | |
| JP4379085B2 (en) | Manufacturing method of high strength and high toughness thick steel plate | |
| JP2010229453A (en) | High strength thick steel plate having excellent toughness to one layer large heat input welding affected zone and method of manufacturing the same | |
| CN101235468A (en) | Atmospheric corrosion resisting steel with yield strength more than 400MPa | |
| CN114480949B (en) | 690 MPa-grade low-yield-ratio weather-resistant welding structural steel, steel plate and manufacturing method thereof | |
| CN110760765A (en) | 600 MPa-grade quenched and tempered steel plate with ultralow cost, high elongation and strain aging embrittlement resistance and manufacturing method thereof | |
| JP2004084068A (en) | Non-tempered low-yield-ratio high-tensile steel excellent in high-temperature strength and method for producing the same | |
| CN103667963A (en) | Low-carbon bainite construction steel with yield ratio of less than 0.8 and production method thereof |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | 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 | ||
| CF01 | Termination of patent right due to non-payment of annual fee | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20110323 Termination date: 20170313 |