CN106011361B - Improve the Mo-Nb-Ti-Mg steel smelting methods of welding performance - Google Patents

Improve the Mo-Nb-Ti-Mg steel smelting methods of welding performance Download PDF

Info

Publication number
CN106011361B
CN106011361B CN201610532216.1A CN201610532216A CN106011361B CN 106011361 B CN106011361 B CN 106011361B CN 201610532216 A CN201610532216 A CN 201610532216A CN 106011361 B CN106011361 B CN 106011361B
Authority
CN
China
Prior art keywords
steel
refining
welding performance
calcium treatment
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
Application number
CN201610532216.1A
Other languages
Chinese (zh)
Other versions
CN106011361A (en
Inventor
朱立光
刘增勋
李玉谦
王硕明
张彩军
孙立根
韩毅华
杜琦铭
成慧梅
许伟
贾改风
王雁
周景
周景一
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.)
North China University of Science and Technology
HBIS Co Ltd Handan Branch
Original Assignee
North China University of Science and Technology
HBIS Co Ltd Handan Branch
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 North China University of Science and Technology, HBIS Co Ltd Handan Branch filed Critical North China University of Science and Technology
Priority to CN201610532216.1A priority Critical patent/CN106011361B/en
Publication of CN106011361A publication Critical patent/CN106011361A/en
Application granted granted Critical
Publication of CN106011361B publication Critical patent/CN106011361B/en
Expired - Fee Related legal-status Critical Current
Anticipated expiration legal-status Critical

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
    • C22C38/04—Ferrous alloys, e.g. steel alloys containing manganese
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21C—PROCESSING OF PIG-IRON, e.g. REFINING, MANUFACTURE OF WROUGHT-IRON OR STEEL; TREATMENT IN MOLTEN STATE OF FERROUS ALLOYS
    • C21C5/00—Manufacture of carbon-steel, e.g. plain mild steel, medium carbon steel or cast steel or stainless steel
    • C21C5/28—Manufacture of steel in the converter
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21C—PROCESSING OF PIG-IRON, e.g. REFINING, MANUFACTURE OF WROUGHT-IRON OR STEEL; TREATMENT IN MOLTEN STATE OF FERROUS ALLOYS
    • C21C7/00—Treating molten ferrous alloys, e.g. steel, not covered by groups C21C1/00 - C21C5/00
    • C21C7/0006—Adding metallic additives
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21C—PROCESSING OF PIG-IRON, e.g. REFINING, MANUFACTURE OF WROUGHT-IRON OR STEEL; TREATMENT IN MOLTEN STATE OF FERROUS ALLOYS
    • C21C7/00—Treating molten ferrous alloys, e.g. steel, not covered by groups C21C1/00 - C21C5/00
    • C21C7/0056—Treating molten ferrous alloys, e.g. steel, not covered by groups C21C1/00 - C21C5/00 using cored wires
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21C—PROCESSING OF PIG-IRON, e.g. REFINING, MANUFACTURE OF WROUGHT-IRON OR STEEL; TREATMENT IN MOLTEN STATE OF FERROUS ALLOYS
    • C21C7/00—Treating molten ferrous alloys, e.g. steel, not covered by groups C21C1/00 - C21C5/00
    • C21C7/04—Removing impurities by adding a treating agent
    • C21C7/06—Deoxidising, e.g. killing
    • 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
    • C22C38/002—Ferrous alloys, e.g. steel alloys containing In, Mg, or other elements not provided for in one single group C22C38/001 - C22C38/60
    • 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
    • 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
    • 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
    • C22C38/12—Ferrous alloys, e.g. steel alloys containing tungsten, tantalum, molybdenum, vanadium, or niobium
    • 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
    • C22C38/14—Ferrous alloys, e.g. steel alloys containing titanium or zirconium

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Mechanical Engineering (AREA)
  • Manufacturing & Machinery (AREA)
  • Treatment Of Steel In Its Molten State (AREA)

Abstract

The invention discloses a kind of Mo Nb Ti Mg steel smelting methods improving welding performance, and the smelting process detailed process technique includes pneumatic steelmaking, LF refining and continuous casting working procedure；The chemical composition and mass percentage of the Mo Nb Ti Mg micro alloyed steels are as follows：C：0.06~0.08%, Mn：1.25~1.60%, S≤0.010%, P≤0.025%, Si：0.20~0.40%, Als：0.010~0.030%, Mo：0.060~0.080%, Ti：0.010~0.020%, Mg：0.002~0.005%, Nb：0.020~0.035%, surplus is Fe and other inevitable impurity.The present invention uses Al final deoxidizings, carries out Mo Nb Ti Mg microalloyings, hence it is evident that improves the obdurability of steel, the control of this forwarding method is simple, and production cost is low, can industrialized production high input energy welding steel.

Description

Improve the Mo-Nb-Ti-Mg steel smelting methods of welding performance
Technical field
The invention belongs to low-alloy steel manufacturing technology fields, and in particular to improve the Mo-Nb-Ti-Mg steel smeltings of welding performance Smelting method.
Background technology
Steel plate is widely used in the infrastructures such as building, bridge, pressure vessel, storage tank, pipeline and ship and large size In building.The enlargement of building element and high stratification development trend require the thickness of steel plate to increase, while having higher synthesis Performance, including higher mechanical property, efficient processing performance and excellent corrosion resistance and antifatigue destructive characteristics etc..
But as the raising of armor plate strength, impact toughness and welding performance are remarkably decreased, welding crack sensibility increases Add.The problem of in order to improve the welding efficiency of engineering structure, use Large Heat Input Welding technology in succession in industry, bring therewith, is just It is that the intensity, toughness of welding heat affected zone declines to a great extent with the raising of weld heat input.Welding heat affected zone（HAZ）Occur tight Grain coarsening, local softening and the embrittlement of weight, general performance are that the toughness of heat affected area is greatly lowered, and threaten engineering structure Safety in utilization.It is therefore prevented that the deterioration of welding process heat affected area performance is the key that exploitation high input energy welding steel.
Studies have shown that grain coarsening is the main reason for steel plate toughness is low when welding, the most effectual way of solution is refinement Austenite grain.Oxides Metallurgy Technology utilizes the fine oxide in steel, by promoting Intragranular Acicular Ferrite forming core to be obviously improved The tissue of welding heat affected zone becomes the most effective technological approaches for solving high input energy welding steel technical barrier, while steel Microalloy treatment generates tiny, disperse, refractory oxide and carbon, nitride particle, is precipitated in grain boundary precipitate, inhibits brilliant Grain length is big, can refine welding heat affected zone crystal grain, improves the strength and toughness of steel, to increase substantially Large Heat Input Welding Energy.
Japanese data and Chinese patent CN102191429A " a method of improving high heat input welding performance of thick steel plates ", Chinese patent CN102191356A " inclusion control method of Large Heat Input Welding steel plate ", Chinese patent CN102296147A " control method of nano-scaled precipitate in thick steel plate for high heat input welding " is mentioned to be carried out using MgO particles Pinning forms 1400 DEG C of high temperatures（Fusing point is high, is not dissolved, does not grow up）And tiny, Dispersed precipitate oxide containing Mg, sulphur Compound carrys out pinning austenite grain growing up at high temperature, while promoting the formation of austenite intragranular acicular ferrite, improves HAZ toughness.And Chinese patent carries out in 50Kg vaccum sensitive stoves, can not try out in industrialized production.
Particle as pinning must have two kinds of characteristics of stability under dispersibility and welding high temperature in steel.In State patent ZL 200710052135.2 " a kind of soldering steel plate in high intensity in use for ocean by large line energy and its manufacturing method " is used Ti2O3、A12O3Particle pinning austenite grain boundary, particle exists in Thermal Cycle area high temperatures, but these particle diameters It is larger, growing up for austenite grain cannot be inhibited well.
The studies above is in control inclusion particle pinning austenite grain boundary and intragranular acicular ferrite is promoted to be formed in effect It is all not enough, is not directed to certain inclusion particles when promoting Intragranular Acicular Ferrite formation, can also promote to a certain extent Into the formation of austenite grain boundary pro-eutectoid ferrite, austenite grain boundary pro-eutectoid ferrite equally makes the toughness of steel plate heat affected area It is greatly lowered.Accordingly, it is determined that microalloy element control inclusion particle pinning austenite grain boundary and the transgranular needle-shaped iron element of promotion The effect that body is formed inhibits the formation of austenite grain boundary pro-eutectoid ferrite, is the pass for improving high input energy welding steel performance Key.
Invention content
In order to solve the above technical problems, the object of the present invention is to provide a kind of raising Large Heat Input Welding performance Mo-Nb- The smelting process of Ti-Mg micro alloyed steels, this method form tiny, Dispersed precipitate refractory oxide in steel, promote transgranular Ferrite forming core, simultaneous oxidation object and carbon, nitride particle are precipitated in grain boundary precipitate, and inhibition crystal grain is grown up and austenite grain boundary Pro-eutectoid ferrite is formed, to reach the requirement of industrialized production high input energy welding steel plate.
The present invention is achieved through the following technical solutions：A kind of Mo-Nb-Ti- improving high input energy welding steel performance Mg microalloying production methods, the smelting process detailed process technique include pneumatic steelmaking, LF refining and continuous casting working procedure；It is described The chemical composition and mass percentage of Mo-Nb-Ti-Mg micro alloyed steels are as follows：C：0.06~0.08%, Mn：1.25~ 1.60%, S≤0.010%, P≤0.025%, Si：0.20~0.40%, Als：0.010~0.030%, Mo：0.060~0.080%, Ti：0.010~0.020%, Mg：0.002~0.005%, Nb：0.020~0.035%, surplus is Fe and other are inevitably miscellaneous Matter.
Pneumatic steelmaking process of the present invention, tapping process are added Mo, Mn, Si, Nb, Al final deoxidizings are used in combination.
LF refining process of the present invention adjusts Al to target content, and Ca processing, then progress Ti, Mg microalloying.
LF refining process of the present invention, refining time >=35min, net argon blowing time >=5min after Calcium treatment, when blowing only Avoid liquid steel level exposed.
LF refining process of the present invention, enter the station liquid steel temperature, the first 1580~1590 DEG C of stove, and stove 1575~1585 pours in company ℃；Aluminum steel feed quantity 1.5-2.5m/t steel after entering the station adds lime, fluorite, drops electrode slugging, aluminium powder is added to make white slag.
LF refining process of the present invention, molten steel before Calcium treatment：S≤0.010%, Als=250~350ppm, T=1580~ 1590℃；Calcium treatment uses Ca-Si lines, Ca-Si line feed quantity 1.5-2.5m/t steel；Molten steel Als=150 after Calcium treatment~ 300ppm, Ca=25~40ppm.When Als is low, Ca-Si line feed quantities remove the limit, and when the first stove of Als high or continuous casting, Ca-Si lines are fed Enter to measure the upper limit.
LF refining process of the present invention carries out Ti, Mg alloying after Calcium treatment, and it is outbound to blow 5min only, out-station temperature 1570~1580 DEG C, the first stove or subcontract in non-week out-station temperature than the upper limit improve 5~10 DEG C.
Pneumatic steelmaking process of the present invention makes steel molten iron [P]≤0.090% used, [S]≤0.045%.
Pneumatic steelmaking process of the present invention, terminal target [C]=0.04~0.06%, [P]≤0.015%, [S]≤ 0.030%, molybdenum-iron, ferromanganese, ferrosilicon, niobium is added in [O]=500~800ppm, 1660~1690 DEG C of tapping temperature in tapping process Iron, ferro-aluminum.
Continuous casting working procedure of the present invention, but, straightening temperature >=900 DEG C, tundish uses carbon-free covering to two cold use weak colds Agent, tundish is suitable for 15~35 DEG C of the degree of superheat；It opens after pouring normally, casting speed control is between 0.90~1.10m/min.
The present invention adjusts the inventive principle of each element composition：
C：It is the essential element for determining steel strength and welding heat affected zone tissue.When C is less than 0.06%, it is difficult to obtain Required intensity；Enter peritectoid when as C high, being not easy to form Intragranular Acicular Ferrite, and steel of the C higher than 0.08% should be avoided to solidify Area influences continuous casting billet quality, therefore designs C 0.06%~0.08%.
Si：It is added as deoxidant element, deoxidation effect is poor when Si is low, but as Si high, promotes microstructure coarsening, and weld It connects hot and cold crack sensitivity to increase, therefore designs Si 0.20%~0.40%.
Mn：It is to ensure the important element of armor plate strength, and increase the important element of carbon equivalent.When Mn is low, intensity drops It is low, and the illeffects enhancing of S compounds；Excessively high Mn makes heat affected area toughness degenerate, therefore design Mn 1.25%~ 1.60%。
P：Be impurity element, increase the cold brittleness of steel, but P is too low can increase smelting cost, thus design P≤ 0.025%。
S：It is the essential element for influencing steel toughness, good de- S not only facilitates the plasticity and toughness for improving steel plate, also helps In control TiN size to inhibit growing up for heat affected area crystal grain.Certain S contents are intentional to inducing intragranular acicular ferrite Justice, the excessively high effects that can influence Mg alloyings of S can also influence the effect of Ca processing, therefore design S≤0.010%.
Mo：Mo postpones pro-eutectoid ferrite transformation, promotes the formation of acicular ferrite and bainite, improves low-alloy steel weldering Stitch the obdurability of metal.Mo improves microalloy element（Nb、Ti）Solid solubility in austenite, delay microalloy carbonitride Precipitation is precipitated under more microalloy elements will be enable to retain to lower temperature from ferrite, so as to generate The precipitation enhancement of bigger.Mo can dissolve in the lattice for the microalloy carbonitride being precipitated in ferrite, be formed（M, Mo） （C, N）（M is microalloy element）, precipitate volume fraction is not only increased, and significantly refine microalloy precipitation size, from And enhance precipitation strength effect.The better heat stability of the carbonitride of microalloy containing Mo is not easy to be roughened under high temperature.Mo is to iron element Body has solution strengthening effect, so that the softening after working hardening and recovery temperature and recrystallization temperature is improved, and improve iron strongly The creep resistance of ferritic effectively inhibits aggregation of the cementite at 450 DEG C~600 DEG C to promote the precipitation of alloy carbide, thus As the most effective alloying element for the heat resistance for improving steel.Mo can improve the hardenability of steel, cold to welding to improve steel The sensibility of crackle, according to national standard, Mo should be controlled 0.08% hereinafter, therefore designing Mo 0.06%~0.08%.
Nb：In microalloy element, Nb is that crystal grain thinning is most effective, is mainly reflected in austenite crystal during reheating Growing up for grain is suppressed, and in the case where not losing toughness, intensity improves.After adding micro Nb, the crystal grain and group of hot rolled steel plate It knitting and is significantly refined, Nb can be effectively reduced the crystallite dimension after recrystallization, for the long large interface of crystal grain after recrystallization, For tiny NbC precipitated phases to it with certain pinning effect, effect of dragging is played in the migration for being dissolved Nb atom pair crystal boundaries.Containing Micro Nb elements are added in the steel for having TiN, the formation of grain boundary ferrite is suppressed, to reduce embrittlement region, sweating heat The toughness of the zone of influence is improved.Nb too high levels promote lath ferrite to be formed, unfavorable to toughness, therefore design Nb 0.020%~0.035%.
Al：Infrastructure elements of the Al as molten-steel deoxidation agent and crystal grain thinning can be formed largely after adding Al deoxidations in steel Al2O3Particle, can be used as steel solidification, phase transformation process Heterogeneous Nucleation core, also can be used as the element being subsequently added The support of oxide forming core.Al content is required in most standard, therefore designs Al 0.010%~0.035%.
Ti：Austenite recrystallization and effect and the Nb of precipitation strength are controlled in low-carbon structure as microalloy element（C、 N）Similar, at 1400 DEG C, the effect of fining austenite grains is most strong.Under conditions of Nb, Ti compound addition, TiN is utilized Heat affected area austenite grain is refined, ideal Ti/N is 2.73.The content for determining Ti, N with this condition, had both ensured TiN's Content is again precipitated its liquid in molten steel.The TiN particles that small and dispersed distribution is precipitated under high temperature effectively hinder austenite Crystal grain is grown up, and the Enhancing Nucleation Density of intragranular acicular ferrite is increased.On the other hand, contain Ti by core of refractory oxide2O3's In matrix phase around duplex impurity, the microcell of poor C, poor Mn are formed, improves ferritic phase temperature（Ac3）, increase ferrite Nuclear driving force（Ac3-Ar3）, promote ferrite crystal grain forming core, therefore design Ti 0.010%~0.020%.
Mg：Appropriate Mg is added, the microinclusions largely containing MgO cores are generated in steel matrix, MgO particles have 2800 DEG C of high-melting-point fully meets the field trash requirement for not dissolving and rising pinning effect at 1400 DEG C, effectively inhibits Austria The growth of family name's body crystal grain.The addition of Mg will disperse, improve the form of Ti oxides simultaneously, remarkably promote intragranular acicular ferrite It is formed, to achieve the purpose that improve heat affected area toughness, therefore designs Mg 0.002%~0.005%.
The advantageous effect generated using above-mentioned technical proposal is：The present invention uses Al final deoxidizings, carries out Mo-Nb-Ti-Mg Microalloying is to form disperse, abundant, tiny MgO, Al2O3、Ti2O3Refractory oxide is core, outer layer attachment Based on the complex inclusion of MnO, MnS, contain Ti2O3Duplex impurity around the poor area existing Mn promote in austenite crystal The formation of acicular ferrite.On the other hand, Mo, Nb of certain content inhibits while crystal grain thinning improves the obdurability of steel The formation of crystal boundary pro-eutectoid ferrite.The tiny inclusion particle of this outer portion and carbon, nitride pinning austenite grain boundary, several sides Face collective effect has fully refined heat affected area crystal grain, hence it is evident that improves the obdurability of steel.The control of this forwarding method is simple, is produced into This is low, can industrialized production high input energy welding steel.
Description of the drawings
Fig. 1 is 200 times of 1 high input energy welding steel heat affected area of embodiment tissue；
Fig. 2 is 200 times of 2 high input energy welding steel heat affected area of embodiment tissue；
Fig. 3 is 200 times of 3 high input energy welding steel heat affected area of embodiment tissue；
Fig. 4 is 1 high input energy welding steel as-cast structure duplex impurity shape appearance figure of embodiment；
Fig. 5 is 1 high input energy welding steel as-cast structure duplex impurity energy spectrum diagram of embodiment；
Fig. 6 is 2 high input energy welding steel as-cast structure duplex impurity shape appearance figure of embodiment；
Fig. 7 is 2 high input energy welding steel as-cast structure duplex impurity energy spectrum diagram of embodiment；
Fig. 8 is 3 high input energy welding steel as-cast structure duplex impurity shape appearance figure of embodiment.
Specific implementation mode
With reference to specific embodiment, the present invention is described in further detail.
Embodiment 1
A kind of Mo-Nb-Ti-Mg steel smelting methods improving welding performance, it is specific as follows：
Smelting high input energy welding steel process is 120t top and bottom combined blown converters -120tLF ladle furnace refinings-continuous casting.
Molten iron condition：Molten iron [P]≤0.090%, [S]≤0.045%.
Converter：Terminal target [C]=0.04~0.06%, [P]≤0.015%, [S]≤0.030%, [O]=500~800ppm, Molybdenum-iron, ferromanganese, ferrosilicon, ferro-niobium, ferro-aluminum is added in 1685 DEG C of tapping temperature in tapping process.
LF：Refining time 40min, net argon blowing time 8min, avoids liquid steel level exposed when blowing only after Calcium treatment.Enter the station steel 1580 DEG C of stove pours in coolant-temperature gage, the first 1585 DEG C of stove, company.Aluminum steel feed quantity 2.0m/t steel after entering the station adds lime, fluorite, drops electrode Slugging adds aluminium powder to make white slag according to slag condition.Molten steel before Calcium treatment：S≤0.010%, Als=280ppm, T=1585 DEG C.Calcium treatment is adopted With Ca-Si lines, Ca-Si line feed quantity 1.85m/t steel, molten steel Als=260ppm after Calcium treatment, Ca=32ppm are carried out after Calcium treatment Ti, Mg alloying, it is outbound to blow 5min only, 1575 DEG C of out-station temperature.
Continuous casting：But, 920 DEG C of straightening temperature, tundish uses carbon-free covering agent to two cold use weak colds, and tundish is suitable for overheat 20 DEG C of degree.It opens after pouring normally, casting speed control is in 1.0m/min.
The chemical composition of the big line energy welding steel of gained is shown in Table 1, and impact property is shown in Table 2.
Embodiment 2
A kind of Mo-Nb-Ti-Mg steel smelting methods improving welding performance, it is specific as follows：
Smelting high input energy welding steel process is 120t top and bottom combined blown converters -120tLF ladle furnace refinings-continuous casting.
Molten iron condition：Molten iron [P]≤0.090%, [S]≤0.045%.
Converter：Terminal target [C]=0.04~0.06%, [P]≤0.015%, [S]≤0.030%, [O]=500~800ppm, Molybdenum-iron, ferromanganese, ferrosilicon, ferro-niobium, ferro-aluminum is added in 1680 DEG C of tapping temperature in tapping process.
LF：Refining time 45min, net argon blowing time 10min, avoids liquid steel level exposed when blowing only after Calcium treatment.It enters the station 1575 DEG C of stove pours in liquid steel temperature, the first 1580 DEG C of stove, company.Aluminum steel feed quantity 1.5m/t steel after entering the station adds lime, fluorite, drop electricity Polarize slag, adds aluminium powder to make white slag according to slag condition.Molten steel before Calcium treatment：S≤0.010%, Als=300ppm, T=1580 DEG C.Calcium treatment Using Ca-Si lines, Ca-Si line feed quantity 1.9m/t steel, molten steel Als=280ppm, Ca=34ppm, Calcium treatment are laggard after Calcium treatment Row Ti, Mg alloying, it is outbound to blow 5min only, 1572 DEG C of out-station temperature.
Continuous casting：But, 905 DEG C of straightening temperature, tundish uses carbon-free covering agent to two cold use weak colds, and tundish is suitable for overheat 22 DEG C of degree.It opens after pouring normally, casting speed control is in 1.0m/min.
The chemical composition of the big line energy welding steel of gained is shown in Table 1, and impact property is shown in Table 2.
Embodiment 3
A kind of Mo-Nb-Ti-Mg steel smelting methods improving welding performance, it is specific as follows：
Smelting high input energy welding steel process is 120t top and bottom combined blown converters -120tLF ladle furnace refinings-continuous casting.
Molten iron condition：Molten iron [P]≤0.090%, [S]≤0.045%.
Converter：Terminal target [C]=0.04~0.06%, [P]≤0.015%, [S]≤0.030%, [O]=500~800ppm, Molybdenum-iron, ferromanganese, ferrosilicon, ferro-niobium, ferro-aluminum is added in 1670 DEG C of tapping temperature in tapping process.
LF：Refining time 42min, net argon blowing time 6min, avoids liquid steel level exposed when blowing only after Calcium treatment.Enter the station steel 1585 DEG C of stove pours in coolant-temperature gage, the first 1590 DEG C of stove, company.Aluminum steel feed quantity 1.9m/t steel after entering the station adds lime, fluorite, drops electrode Slugging adds aluminium powder to make white slag according to slag condition.Molten steel before Calcium treatment：S≤0.010%, Als=320ppm, T=1590 DEG C.Calcium treatment is adopted With Ca-Si lines, Ca-Si line feed quantity 1.75m/t steel, molten steel Als=300ppm after Calcium treatment, Ca=30ppm are carried out after Calcium treatment Ti, Mg alloying, it is outbound to blow 5min only, 1575 DEG C of out-station temperature.
Continuous casting：But, 910 DEG C of straightening temperature, tundish uses carbon-free covering agent to two cold use weak colds, and tundish is suitable for overheat 25 DEG C of degree.It opens after pouring normally, casting speed control is in 1.0m/min.
The chemical composition of the big line energy welding steel of gained is shown in Table 1, and impact property is shown in Table 2.
Embodiment 4
A kind of Mo-Nb-Ti-Mg steel smelting methods improving welding performance, it is specific as follows：
Smelting high input energy welding steel process is 80t top and bottom combined blown converters -80tLF ladle furnace refinings-continuous casting.
Molten iron condition：Molten iron [P]≤0.090%, [S]≤0.045%.
Converter：Terminal target [C]=0.04~0.06%, [P]≤0.015%, [S]≤0.030%, [O]=500~800ppm, Molybdenum-iron, ferromanganese, ferrosilicon, ferro-niobium, ferro-aluminum is added in 1660 DEG C of tapping temperature in tapping process.
LF：Refining time 38min, net argon blowing time 5min, avoids liquid steel level exposed when blowing only after Calcium treatment.Enter the station steel 1578 DEG C of stove pours in coolant-temperature gage, the first 1586 DEG C of stove, company.Aluminum steel feed quantity 2.0m/t steel after entering the station adds lime, fluorite, drops electrode Slugging adds aluminium powder to make white slag according to slag condition.Molten steel before Calcium treatment：S≤0.010%, Als=350ppm, T=1586 DEG C.Calcium treatment is adopted With Ca-Si lines, Ca-Si line feed quantity 2.5m/t steel, molten steel Als=300ppm after Calcium treatment, Ca=25ppm are carried out after Calcium treatment Ti, Mg alloying, it is outbound to blow 5min only, 1570 DEG C of out-station temperature.First stove or non-week subcontract 1585 DEG C of out-station temperature.
Continuous casting：But, 900 DEG C of straightening temperature, tundish uses carbon-free covering agent to two cold use weak colds, and tundish is suitable for overheat 15 DEG C of degree.It opens after pouring normally, casting speed control is in 0.90m/min.
The chemical composition of the big line energy welding steel of gained is shown in Table 1, and impact property is shown in Table 2.
Embodiment 5
A kind of Mo-Nb-Ti-Mg steel smelting methods improving welding performance, it is specific as follows：
Smelting high input energy welding steel process is 160t top and bottom combined blown converters -160tLF ladle furnace refinings-continuous casting.
Molten iron condition：Molten iron [P]≤0.090%, [S]≤0.045%.
Converter：Terminal target [C]=0.04~0.06%, [P]≤0.015%, [S]≤0.030%, [O]=500~800ppm, Molybdenum-iron, ferromanganese, ferrosilicon, ferro-niobium, ferro-aluminum is added in 1690 DEG C of tapping temperature in tapping process.
LF：Refining time 35min, net argon blowing time 7min, avoids liquid steel level exposed when blowing only after Calcium treatment.Enter the station steel 1580 DEG C of stove pours in coolant-temperature gage, the first 1590 DEG C of stove, company.Aluminum steel feed quantity 2.5m/t steel after entering the station adds lime, fluorite, drops electrode Slugging adds aluminium powder to make white slag according to slag condition.Molten steel before Calcium treatment：S≤0.010%, Als=250ppm, T=1590 DEG C.Calcium treatment is adopted With Ca-Si lines, Ca-Si line feed quantity 1.5m/t steel, molten steel Als=150ppm after Calcium treatment, Ca=40ppm are carried out after Calcium treatment Ti, Mg alloying, it is outbound to blow 5min only, 1580 DEG C of out-station temperature.First stove or non-week subcontract 1590 DEG C of out-station temperature.
Continuous casting：But, 910 DEG C of straightening temperature, tundish uses carbon-free covering agent to two cold use weak colds, and tundish is suitable for overheat 35 DEG C of degree.It opens after pouring normally, casting speed control is in 1.10m/min.
The chemical composition of the big line energy welding steel of gained is shown in Table 1, and impact property is shown in Table 2.
Chemical composition in 1 embodiment 1-5 of table（mass%）
C Mn S P Si Als Mo Ti Mg Nb
Embodiment 1 0.07 1.42 0.005 0.019 0.25 0.026 0.07 0.020 0.0025 0.035
Embodiment 2 0.06 1.51 0.005 0.022 0.21 0.028 0.07 0.017 0.0031 0.027
Embodiment 3 0.06 1.55 0.006 0.017 0.23 0.030 0.07 0.013 0.0022 0.029
Embodiment 4 0.07 1.25 0.006 0.023 0.40 0.030 0.06 0.020 0.0050 0.020
Embodiment 5 0.08 1.60 0.010 0.025 0.20 0.010 0.08 0.010 0.0020 0.035
Note：Surplus is iron and inevitable impurity
The impact property of 2 embodiment of table（Heat input 150KJ/cm）
Gap position Notch type Test temperature/DEG C Impact absorbing energy/J
Embodiment 1 Melt run+2mm VHT2 V-type -20 188.4
Embodiment 2 Melt run+2mm VHT2 V-type -20 197.1
Embodiment 3 Melt run+2mm VHT2 V-type -20 195.5
Embodiment 4 Melt run+2mm VHT2 V-type -20 192.6
Embodiment 5 Melt run+2mm VHT2 V-type -20 194.1
Table 2 list 40mm steel plate weld heat inputs be 150KJ/cm when, embodiment 1-5 welding heat affected low temp area punching Hit toughness value.Steel plate produced by the invention has rational heat affected zone organization structure, by formed it is abundant it is transgranular it is needle-shaped, Piece columnar ferrite and granular bainite, and effective inclusion particle have refined heat affecting significantly to the pinning of austenite grain boundary District's groups are knitted, and the obdurability of steel is made to significantly improve.
Attached drawing 1-3 can be seen that crystal grain is tiny in high input energy welding steel heat affected zone organization, and microscopic structure mainly has Ferrite and pearlite forms.Fig. 4 is typical acicular ferrite in 1 as-cast structure of embodiment, and size is about 3 μm, induces it The field trash of generation is mainly Mg, and the duplex impurity that the elements such as Al, Si are formed promotes the shape of austenite intragranular acicular ferrite At, keep the crystal grain of welding heat affected zone tiny, while crystal grain thinning improves the obdurability of steel, inhibition crystal boundary proeutectoid ferrite The formation of body, ballistic work absorption value increase several times.The field trash energy spectrum diagram and reality of the induction acicular ferrite of embodiment 3 in Fig. 8 It is similar to apply example 2, therefore omits.Embodiment 4 and 5 product figure of embodiment are similar to embodiment 1-3, therefore omit.
The above embodiments are only used to illustrate and not limit the technical solutions of the present invention, although with reference to above-described embodiment to this hair It is bright to be described in detail, it will be understood by those of ordinary skill in the art that：Still can the present invention be modified or be waited With replacing, without departing from the spirit or scope of the invention, or any substitutions, the power in the present invention should all be covered In sharp claimed range.

Claims (6)

1. a kind of Mo-Nb-Ti-Mg steel smelting methods improving welding performance, which is characterized in that the smelting process detailed process Technique includes pneumatic steelmaking, LF refining and continuous casting working procedure；The chemical composition and quality percentage of the Mo-Nb-Ti-Mg micro alloyed steels Content is as follows：C：0.06~0.08%, Mn：1.25~1.60%, S≤0.010%, P≤0.025%, Si：0.20~0.40%, Als：0.010~0.030%, Mo：0.060~0.080%, Ti：0.010~0.020%, Mg：0.002~0.005%, Nb：0.020 ~0.035%, surplus is Fe and other inevitable impurity, the pneumatic steelmaking process, tapping process be added Mo, Mn, Si, Nb, is used in combination Al final deoxidizings, the pneumatic steelmaking process, terminal target [C]=0.04~0.06%, [P]≤0.015%, [S]≤ 0.030%, molybdenum-iron, ferromanganese, ferrosilicon, niobium is added in [O]=500~800ppm, 1660~1690 DEG C of tapping temperature in tapping process Iron, ferro-aluminum, the LF refining process adjustment Al to target content, and Ca processing, then carry out Ti, Mg microalloying, the LF Refining procedure, molten steel before Calcium treatment：S≤0.010%, Als=250~350ppm, T=1580~1590 DEG C；Calcium treatment uses Ca- Si lines, Ca-Si line feed quantity 1.5-2.5m/t steel；Molten steel Als=150~300ppm after Calcium treatment, Ca=25~40ppm.
2. a kind of Mo-Nb-Ti-Mg steel smelting methods improving welding performance according to claim 1, which is characterized in that The LF refining process, refining time >=35min, net argon blowing time >=5min, avoids liquid steel level naked when blowing only after Calcium treatment Dew.
3. a kind of Mo-Nb-Ti-Mg steel smelting methods improving welding performance according to claim 2, which is characterized in that The LF refining process, enter the station liquid steel temperature, the first 1580~1590 DEG C of stove, and 1575~1585 DEG C of stove pours in company；Aluminum steel after entering the station Feed quantity 1.5-2.5m/t steel adds lime, fluorite, drops electrode slugging, aluminium powder is added to make white slag.
4. a kind of Mo-Nb-Ti-Mg steel smelting methods improving welding performance according to claim 3, which is characterized in that The LF refining process carries out Ti, Mg alloying after Calcium treatment, and it is outbound to blow 5min only, 1570~1580 DEG C of out-station temperature, and first It subcontracts out-station temperature in stove or non-week and improves 5~10 DEG C than the upper limit.
5. a kind of Mo-Nb-Ti-Mg steel smelting methods improving welding performance according to claim 1, which is characterized in that The pneumatic steelmaking process makes steel molten iron [P]≤0.090% used, [S]≤0.045%.
6. special according to a kind of Mo-Nb-Ti-Mg steel smelting methods improving welding performance of claim 1-5 any one of them Sign is that the continuous casting working procedure, but, straightening temperature >=900 DEG C, tundish uses carbon-free covering agent to two cold use weak colds, intermediate Packet is suitable for 15~35 DEG C of the degree of superheat；It opens after pouring normally, casting speed control is between 0.90~1.10m/min.
CN201610532216.1A 2016-07-08 2016-07-08 Improve the Mo-Nb-Ti-Mg steel smelting methods of welding performance Expired - Fee Related CN106011361B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201610532216.1A CN106011361B (en) 2016-07-08 2016-07-08 Improve the Mo-Nb-Ti-Mg steel smelting methods of welding performance

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201610532216.1A CN106011361B (en) 2016-07-08 2016-07-08 Improve the Mo-Nb-Ti-Mg steel smelting methods of welding performance

Publications (2)

Publication Number Publication Date
CN106011361A CN106011361A (en) 2016-10-12
CN106011361B true CN106011361B (en) 2018-07-31

Family

ID=57108288

Family Applications (1)

Application Number Title Priority Date Filing Date
CN201610532216.1A Expired - Fee Related CN106011361B (en) 2016-07-08 2016-07-08 Improve the Mo-Nb-Ti-Mg steel smelting methods of welding performance

Country Status (1)

Country Link
CN (1) CN106011361B (en)

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN113278877A (en) * 2021-02-01 2021-08-20 南京钢铁股份有限公司 High-cleanliness pipeline steel and smelting method thereof

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1189193A (en) * 1996-04-17 1998-07-29 新日本制铁株式会社 Steel having improved toughness in welding heat-affected zone
CN1380910A (en) * 2000-05-09 2002-11-20 新日本制铁株式会社 Thick steel plate being excellent in CTOD characteristic in welding heat affected zone and having yield strength of 460 MPa or more
CN1894434A (en) * 2003-12-19 2007-01-10 新日本制铁株式会社 Steel plates for ultra-high-strength linepipes and ultra-high-strength linepipes having excellent low-temperature toughness and manufacturing methods thereof
CN102080193A (en) * 2011-01-10 2011-06-01 东北大学 Structural steel for welding with ultra-great heat input and manufacturing method thereof
CN104651714A (en) * 2013-11-19 2015-05-27 新日铁住金株式会社 Steel sheet

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1189193A (en) * 1996-04-17 1998-07-29 新日本制铁株式会社 Steel having improved toughness in welding heat-affected zone
CN1380910A (en) * 2000-05-09 2002-11-20 新日本制铁株式会社 Thick steel plate being excellent in CTOD characteristic in welding heat affected zone and having yield strength of 460 MPa or more
CN1894434A (en) * 2003-12-19 2007-01-10 新日本制铁株式会社 Steel plates for ultra-high-strength linepipes and ultra-high-strength linepipes having excellent low-temperature toughness and manufacturing methods thereof
CN102080193A (en) * 2011-01-10 2011-06-01 东北大学 Structural steel for welding with ultra-great heat input and manufacturing method thereof
CN104651714A (en) * 2013-11-19 2015-05-27 新日铁住金株式会社 Steel sheet

Also Published As

Publication number Publication date
CN106011361A (en) 2016-10-12

Similar Documents

Publication Publication Date Title
CN103667953B (en) A kind of low environment crack sensitivity ultra-high strength and toughness marine mooring chain steel and manufacture method thereof
CN102080193B (en) Structural steel for welding with ultra-great heat input and manufacturing method thereof
CN102418036B (en) 15MnNiDR low alloy steel plate for low temperature pressure vessel and production method thereof
CN101684534B (en) Steel plate adapting to large-linear energy welding and manufacturing method thereof
CN102242309B (en) Production method of boron-containing petroleum storage tank steel plate for ultra-high heat input welding
CN102732789A (en) High-performance ocean platform steel and its production method
CN102345061B (en) Q690D quality structural medium steel plate and production method thereof
CN104087850B (en) A kind of anti-H2Anchor bar steel and the production method for mine of S corrosion
CN101787489A (en) Easy-welding low-carbon bainitic steel and manufacturing method thereof
CN109868414A (en) The excellent yield strength of cold temperature impact >=430MPa pressure vessel steel and production method
CN102653845A (en) Steel plate for LPG (Liquefied Petroleum Gas) ship storage tank and production method of steel plate
CN103320719A (en) Low-cost large-heat-input-weldable high-toughness steel plate and manufacturing method thereof
CN102732797B (en) 800MPa grade low welding crack sensitivity steel plate and its manufacturing method
CN105714193A (en) Oxide-enhanced high heat input welding steel plate
CN105177420A (en) S275NL high-tenacity and fine-grain structure steel plate and preparation method thereof
CN104364405A (en) Ultrahigh-tensile-strength steel plate for welding
CN107557662A (en) Quenching and tempering type 800MPa levels low-cost and easy-to welds steel plate and its production method
CN107287506A (en) A kind of 650MPa grades of medium temperature and medium pressure boiler plate and its production method
CN103469066A (en) Method for producing high-formability steel plate by using heavy and medium plate mill and steel plate manufactured by method
CN105296855A (en) Steel plate capable of performing high heat input welding for ocean platform and preparation method
CN107574372A (en) A kind of high tenacity high input energy welding steel and its production method
CN103667921A (en) Thick steel plate with high strength and toughness as well as uniform performance in thickness direction and production method of thick steel plate
CN105907920B (en) Improve the microalloying method of high input energy welding steel performance
CN106011361B (en) Improve the Mo-Nb-Ti-Mg steel smelting methods of welding performance
CN101967604B (en) Boron-nitrogen composite microalloyecd steel allowing for high heat input welding and manufacturing method

Legal Events

Date Code Title Description
C06 Publication
PB01 Publication
C10 Entry into substantive examination
SE01 Entry into force of request for substantive examination
TA01 Transfer of patent application right
TA01 Transfer of patent application right

Effective date of registration: 20180507

Address after: 063009 Xinhua Road 46, Lunan District, Tangshan City, Hebei

Applicant after: North China Polytechnics

Applicant after: River steel Limited by Share Ltd Handan branch

Address before: 063009 Xinhua Road 46, Lunan District, Tangshan City, Hebei

Applicant before: North China Polytechnics

GR01 Patent grant
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: 20180731

Termination date: 20200708