CN108754336A - A kind of special thick 1.2311 slab of mould steel and its production method - Google Patents

A kind of special thick 1.2311 slab of mould steel and its production method Download PDF

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Publication number
CN108754336A
CN108754336A CN201810969366.8A CN201810969366A CN108754336A CN 108754336 A CN108754336 A CN 108754336A CN 201810969366 A CN201810969366 A CN 201810969366A CN 108754336 A CN108754336 A CN 108754336A
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steel
temperature
argon
slag
slab
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CN108754336B (en
Inventor
许少普
符可义
朱书成
李忠波
刘庆波
杨阳
康文举
唐郑磊
张占杰
张涛
庞百鸣
于飒
董真真
袁少威
袁继恒
袁永旗
朱先兴
王英杰
薛艳生
石教兴
蒋鹏
杨东
李亮
赵湖
袁高俭
徐双献
郑海明
陈熙
陈良
韩学文
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Nanyang Hanye Special Steel Co Ltd
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Nanyang Hanye Special Steel Co Ltd
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    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/02—Ferrous alloys, e.g. steel alloys containing silicon
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • 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
    • 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
    • C21C7/10—Handling in a vacuum
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D1/00—General methods or devices for heat treatment, e.g. annealing, hardening, quenching or tempering
    • C21D1/26—Methods of annealing
    • C21D1/28—Normalising
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D3/00—Diffusion processes for extraction of non-metals; Furnaces therefor
    • C21D3/02—Extraction of non-metals
    • C21D3/06—Extraction of hydrogen
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D8/00—Modifying the physical properties by deformation combined with, or followed by, heat treatment
    • C21D8/02—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips
    • C21D8/0221—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips characterised by the working steps
    • C21D8/0226—Hot rolling
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D8/00—Modifying the physical properties by deformation combined with, or followed by, heat treatment
    • C21D8/02—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips
    • C21D8/0247—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips characterised by the heat treatment
    • C21D8/0257—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips characterised by the heat treatment with diffusion of elements, e.g. decarburising, nitriding
    • 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
    • C22C38/04—Ferrous alloys, e.g. steel alloys containing manganese
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
    • C22C38/22—Ferrous alloys, e.g. steel alloys containing chromium with molybdenum or tungsten
    • 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
    • C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
    • C22C38/24—Ferrous alloys, e.g. steel alloys containing chromium with vanadium
    • 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
    • C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
    • C22C38/38—Ferrous alloys, e.g. steel alloys containing chromium with more than 1.5% by weight of manganese
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
    • Y02P10/00—Technologies related to metal processing
    • Y02P10/20—Recycling

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  • Crystallography & Structural Chemistry (AREA)
  • Treatment Of Steel In Its Molten State (AREA)
  • Heat Treatment Of Steel (AREA)

Abstract

The invention discloses a kind of special thick 1.2311 slab of mould steel and its production methods, belong to special thick technical field of mold steel, include the chemical composition of following mass percent：C：0.4%~0.44%, Si：0.3~0.5%, Mn：1.45~1.55%, P≤0.015%, S≤0.005%, Cr：1.5%~1.7%, Mo：3.5%~4.5%, V：0.025%-0.035%, other is Fe and relict element；Technological process is：Molten iron（KR desulfurization）→ converter（Argon station）→ LF refining → VD vacuum processings → molding cast → steel ingot cleaning（It is cleaned out in the 8h of water cooled mo(u)ld ingot casting after demoulding）→ steel ingot sent in the 5h after cleaning out roll shove charge → rolling → heap it is cold → heat treatment → finishing → outer inspection → storage.The defects of thick 1.2311 slab of mould steel of spy prepared by the invention is provided with high polishing performance, good processability, excellent obdurability, and hardness meets the technology requirement of 310-340HB, and dense structure, appearance is good, and ultrasonic inspection is pin-free, core.

Description

A kind of special thick 1.2311 slab of mould steel and its production method
Technical field
The present invention relates to special thick technical field of mold steel, and in particular to a kind of special thick 1.2311 slab of mould steel and its production Method.
Background technology
1.2311 be that widely applied plastic die steel, the addition element Cr, Mo, Ni etc. are carried significantly in the world High rustless property and polishing performance, the indexs such as polishing performance, intensity, through hardening performance are above P20.The steel is big suitable for manufacture Type, super-huge plastic mould, since the steel is mainly used for making high-accuracy plastic mould, therefore it is required that steel is pure, tissue causes It is close, steel plate hardness requirement narrow range, and uniformity requirements are high, it is desirable that there is good machinability and wearability, therefore such It is special that steel grade production difficulty is big, technological equipment requires, and production cost is high.Domestic steel mill is produced using quenched, complex procedures, It is easy during quenched and fire is cut and causes to crack in the process, it is more demanding to equipment and process equipment, therefore to ensure spy Thick mechanical performance reaches Customer Standard requirement and ensures its service life, and it is urgent to develop a kind of 1.2311 grinding tool steel of 400mm or more thickness In the eyebrows and eyelashes.
Notification number is that the patent document of CN105925889A discloses a kind of special 1.2311 mold steel plate of think gauge, steel plate with Fe is basic element and includes following component：C0.35 ~ 0.45% by mass percentage, Si0.20 ~ 0.40%, Mn1.30 ~ 1.60%, P≤0.020%, S≤0.010%, Cr1.80 ~ 2.00%, Mo0.15 ~ 0.25%, Al0.01 ~ 0.05%, Ni≤0.30%, Cu ≤ 0.25%, B0.001 ~ 0.002% and inevitable impurity element；Carbon equivalent 0.98 ~ 1.1.The manufacturing process of the steel plate includes The processes such as blank smelting, continuous cast round billets, heating, high-pressure water descaling, rolling, aligning, slow cooling, flaw detection, tempering, invention manufacture 1.2311 mold steel plate thickness are only 160-250mm, and average surface 30 ~ 36HRC of hardness of steel plate, core hardness is >=28HRC, And there is no techniques such as Argon, vacuum processing, normalizing rapid cooling in the preparation process of the invention, the slab internal flaw ratio produced More serious, product qualification rate is relatively low.
Notification number is that the patent document of CN105803299A discloses a kind of life of special thick high cleanliness plastic steel plate for die Production method, including smelting, continuous casting, electroslag remelting, heating, rolling, annealing and heat treatment procedure；The weight of the steel plate chemical composition Measuring degree is：C：0.35%~0.40%,Si：0.20%~0.45%,Mn：1.10%~1.50%,P≤0.020%,S≤ 0.010%,Ni：0.05~1.25%,Cr：1.8%~2.00%,Mo：0.20% ~ 0.50%, TAl0.020% ~ 0.050%, surplus be Fe and Inevitable impurity.The invention is handled using electroslag remelting, and the steel plate thickness produced is limited, is 420mm, the invention is in life The processing steps such as molten iron pretreatment, Argon processing, VD refinings, bad mechanical property are not carried out during production.
Invention content
In view of the above-mentioned problems, the present inventor gropes by repetition test, a kind of special thick 1.2311 mould steel of production are obtained Production method, so as to complete the present invention.
Therefore, the purpose of the present invention is to provide a kind of techniques that reduction production cost produces 1.2311 slabs.
Another object of the present invention is to provide a kind of inexpensive 1.2311 slabs.
In order to solve the above technical problems, the technical solution adopted by the present invention is：
A kind of 1.2311 slab of special thick mould steel, includes the chemical composition of following mass percent：C：0.4%~0.44%, Si： 0.3~0.5%, Mn：1.45~1.55%, P≤0.015%, S≤0.005%, Cr：1.5%~1.7%, Mo：3.5%~4.5%, V： 0.025%-0.035%, other is Fe and relict element.
Further, the thickness of the slab is 400-1000mm.
Further, a kind of production method of spy's 1.2311 slab of thick mould steel, technological process be：Molten iron （KR desulfurization）→ converter（Argon station）→ LF refining → VD vacuum processings → molding cast → steel ingot cleaning（Water cooled mo(u)ld ingot casting is demoulding It is cleaned out in 8h afterwards）→ steel ingot sent in the 5h after cleaning out roll shove charge → rolling → heap it is cold → heat treatment → finishing → Outer inspection → storage；
KR hot metal pretreatment technologies：The molten iron that arrives at a station must take off preceding slag and take off rear slag, ensure liquid level thickness of slag layer≤22mm, molten iron warp Ensure molten iron S≤0.005% after KR stirring desulphurizations, ensures desulfurization period≤20min, desulfurization temperature drop≤20 DEG C；
Converter smelting process：Enter stove molten iron S≤0.005%, P≤0.015%, molten iron temperature >=1270 DEG C, steel scrap strictly uses excellent Matter leftover pieces, slag making basicity R are controlled by 2.5-4.0, tapping target P≤0.01%, C >=0.4%, S≤0.005%, and tapping temperature is big In or be equal to 1660 DEG C, in tapping process into ladle Si-Al-Ba-Ca, manganeisen, Antaciron and lime, fluorite；
Argon blowing process：Argon station is added at one time aluminum steel, and strong Argon 3min, flow 250-500NL/min, steel are required in argon station Liquid level bore hole diameter control is greater than or equal to 1560 DEG C in 400~500mm, from argon station temperature；
LF refining technique：Whole Argon in refining process, Argon intensity are adjusted according to different links needs, and refining slag is added Material, basicity are controlled by 4.0-6.0, and refinement and deoxidation agent is based on calcium carbide, aluminum shot, ferrosilicon powder, and addition is according to steel oxygen content in water And make white slag situation and be added in right amount, heating process selects appropriate electric current to be heated according to rhythm is more than needed with temperature conditions, heats Time presses two secondary controls, a heating 8-11min, two heating 7-11min；
VD refinery practices：VD vacuum degrees must reach 70Pa hereinafter, the dwell time it is necessary >=22min, soft blow 2- after vacuum breaker 5min is not blown, and molten steel must not be exposed during soft blow, normal to wrap the minute vacuumized online and be：（Molten steel temperature before vacuumizing Degree-target temperature leaving from station）/1.7；
Die casting process：Conventional mould pouring temperature is controlled according to 1550-1555 DEG C, and molten steel has to carry out soft blow argon work after arriving at a station Skill, argon blowing time control are opened after requirement calmness 5min after 5-10min, Argon and are poured, and cap mouth is must assure that after cast Heat insulation effect；
Heating process:In heating process, heating speed and heating temperature are controlled, 3-4 hours double steels, are turned over before heat preservation terminates After steel, it is warming up to holding temperature, after remaining soaking time heat preservation, in tapping process, increases gas flow, continues Heating, after tapping, pincers, which are hung, should rest on right over steel rider road；
Rolling mill practice：Based on roughing, supplemented by finish rolling；Roughing is using percentage pass reduction gradually incremental measure, maximum rolling road Secondary reduction ratio is more than 15%；Rough rolling step：Percentage pass reduction gradually rises, the finish rolling stage：Percentage pass reduction continuously decreases；
The cold technique of heap:Tempering being carried out into burial pit after steel plate rolling and expanding hydrogen technique, car type furnace is then taken to be heated to 500 DEG C And it comes out of the stove after keeping the temperature 96h；
Heat treatment process：It is 830 DEG C, soaking time 13h, red temperature 640-660 first to use normalizing rapid cooling, normalizing temperature ℃；Then it is tempered, temperature is 600 DEG C, soaking time 26h.
Further, in the converter smelting process, gear is used before terminating before tapping with slag tapping before floating plug gear, tapping Slag bores pushing off the slag, ensures thickness of slag layer≤30mm, whole Argon is required in converter tapping process.
Further, it requires, according to slag making situation, to add deoxidation in the LF refining technique, in two heating process Agent is added silicon-calcium wire before leaving from station, must shut off argon gas, 1600 ± 15 DEG C of upper steel temperature before adding silicon-calcium wire.
Further, in the VD refinery practices, ensure that coverture is paved with molten steel face, must shut off argon before adding coverture Gas, upper 1550-1570 DEG C of steel temperature.
Further, in the heating process, heating temperature is 700-850 DEG C, is heated up 60-100 DEG C per hour, heat preservation temperature Degree is 1300-1320 DEG C.
The beneficial effects of the invention are as follows：Ensure its service life to ensure that special thick mechanical performance reaches Customer Standard requirement, Our company carries out crucial performance by means such as theory analysis, processing simulation, experimental study, actual production product testings Key technology research successfully develops 1.2311 grinding tool steel of 400mm or more thickness, and agreement is fully met through carrying out performance detection It can require, chemical composition requires and mechanical property requirements see the table below.
The present invention uses molten iron（KR desulfurization）→ converter（Argon station）→ LF refining → VD vacuum processings → molding cast → steel Ingot is cleared up（It is cleaned out in the 8h of water cooled mo(u)ld ingot casting after demoulding）→ steel ingot is sent in the 5h after cleaning out rolls shove charge → rolls System → heap is cold → heat treatment → finishing → outer inspection → storage.
Production process is vacuum-treated by KR desulfurizing irons, converter, LF refining, VD, molding is poured into a mould, and kiln process converter is useless Steel takes leftover pieces, molten iron charge weight error to be controlled by ± 1t, and the control of tapping carbon is >=0.05%, and tap P≤0.012%, and S≤ 0.015%, tapping temperature >=1660 DEG C avoid tapping slag.
Gon technics reduce gaseous impurity in air and are mixed into, ensure the purity of material, greatly reduce inside slab and table The defect in face.
LF refining uses big quantity of slag slagging process, it is desirable that one heating end clinker of refining must bleach or yellowish-white, white slag guarantor >=35min is held the time, alloy is added in refining two heating processes.It is required that the finishing slag that refining terminates is good fluidity, viscosity Suitable foam white slag, refining total time require control in 60min or more.
VD vacuum refinings：The VD dwell times are according to >=22min execution, preferably under the vacuum degree of 67Pa, pressure maintaining period steel Water, which seethes, to work well.
Heating process:In heating process, the steel grade alloy content is higher, and poor thermal conductivity need to especially control heating speed And heating temperature, prevent steel ingot from bursting and decarburization phenomenon, the 3-4 hours double steels before heat preservation terminates after double steel, are warming up to guarantor Temperature in tapping process, increases gas flow, continues to heat up, to make up because going out after remaining soaking time heat preservation Thermal loss caused by steel process, in-furnace temperature reaches holding temperature requirement after ensureing fire door closing.After tapping, pincers hang and should stop It stays in right over steel rider road, to its double steel or can be melted down in time after steel is stuck up in steel ingot rolling with guarantee, reduce temperature loss, Heating ensures that the big soft reduction process of high temperature low speed is taken in abundant solid solution of the micro alloying element in austenitic area, cogging stage, fully Dendrite in broken steel ingot, deformation extent is bigger, and forming core area density and driving force are bigger, and crystal grain is thinner after recrystallizing repeatedly It is small.
Rolling mill practice：Based on roughing, supplemented by finish rolling.Roughing is rolled using percentage pass reduction gradually incremental measure, maximum Percentage pass reduction processed is more than 15%, is conducive to the pressing of special heavy plate heart defect in this way.Rough rolling step：Percentage pass reduction gradually rises Height advantageously ensures that heart defect is pressed under the conditions of smaller overall reduction.The finish rolling stage：Percentage pass reduction is gradual It reduces, this is conducive to the plate form control of special heavy plate, mitigates the pressure of straightener.
The cold technique of heap:Tempering being carried out into burial pit after steel plate rolling and expanding hydrogen technique, main purpose is with steel plate thickness The increase of degree, row's hydrogen effect worse and worse, easily causes inside steel plate and white-spot defects occurs and influence matter inside steel plate in process air cooler Amount, after take car type furnace to be heated to 500 DEG C and come out of the stove after keeping the temperature 96h, hydrogen content reduce internal soundness it is excellent, dense structure.
The present invention is appropriate to adjust the conjunctions such as C, Mn, V, Mo, Cr in steel on the component base of original 1.2311 die steel The content and ratio of gold element, and the harmful element content of the influence such as P, S steel plate plasticity and toughness in steel is strictly controlled, while stringent control The heating cycle of steel rolling processed, the operation of rolling uses based on roughing, supplemented by finish rolling.Roughing is gradually incremental using percentage pass reduction Measure, maximum rolling pass reduction rate are more than 15%, are conducive to the pressing of special heavy plate heart defect in this way.Rough rolling step：Passage pressure Lower rate gradually rises, and advantageously ensures that heart defect is pressed under the conditions of smaller overall reduction.The finish rolling stage：Passage Reduction ratio continuously decreases, and to ensure template, heat treatment is using hardening and tempering process to ensure that 1.2311 steel grade super-thick steel plates Performance indicator reaches requirement.Spy's 1.2311 slab of thick mould steel generated using the present invention, product qualification rate reach 97% or more, Has a high polishing performance, good processability, excellent obdurability, hardness meets the technology requirement of 310-340HB, tissue The defects of densification, appearance is good, and ultrasonic inspection is pin-free, core, satisfactory mechanical property, excellent combination property.
Specific implementation mode
In order to make the object, technical scheme and advantages of the embodiment of the invention clearer, below to the skill of the embodiment of the present invention Art scheme is clearly and completely described.Obviously, described embodiment is a part of the embodiment of the present invention, rather than complete The embodiment in portion.Based on described the embodiment of the present invention, every other implementation that those of ordinary skill in the art are obtained Example, shall fall within the protection scope of the present invention.
The technological process that the present invention uses for：Molten iron（KR desulfurization）→ converter（Argon station）→ LF refining → VD vacuum processings → Mold cast → steel ingot cleaning（It is cleaned out in the 8h of water cooled mo(u)ld ingot casting after demoulding）→ steel ingot is in the 5h after cleaning out Send roll shove charge → rolling → heap it is cold → heat treatment → finishing → outer inspection → storage.
Embodiment is as follows：
A kind of 1.2311 slab of special thick mould steel, guarantee thickness are 400mm-1000mm, include the chemistry of following mass percent Ingredient：C：0.4%~0.44%, Si：0.3~0.5%, Mn：1.45~1.55%, P≤0.015%, S≤0.005%, Cr：1.5%~ 1.7%,Mo：3.5%~4.5%, V：0.025%-0.035%, other is Fe and relict element.
KR hot metal pretreatment technologies：The molten iron that arrives at a station must take off preceding slag and take off rear slag, ensure liquid level thickness of slag layer≤22mm, iron Water ensures molten iron S≤0.005% after KR stirring desulphurizations, ensures desulfurization period≤20min, desulfurization temperature drop≤20 DEG C；
Converter smelting process：Enter stove molten iron S≤0.005%, P≤0.015%, molten iron temperature >=1270 DEG C, steel scrap strictly uses excellent Matter leftover pieces, slag making basicity R are controlled by 2.5-4.0, tapping target P≤0.01%, C >=0.4%, S≤0.005%, and tapping temperature is big In or be equal to 1660 DEG C, in tapping process into ladle Si-Al-Ba-Ca, manganeisen, Antaciron and lime, fluorite, before tapping Slag tapping before being kept off with floating plug, tapping use slag retaining cone pushing off the slag before terminating, ensure thickness of slag layer≤30mm, in converter tapping process It is required that whole Argon；
Argon blowing process：Argon station is added at one time aluminum steel, and strong Argon 3min, flow 250-500NL/min, steel are required in argon station Liquid level bore hole diameter control is greater than or equal to 1560 DEG C in 400~500mm, from argon station temperature；
LF refining technique：Whole Argon in refining process, Argon intensity are adjusted according to different links needs, and refining slag is added Material, basicity are controlled by 4.0-6.0, and refinement and deoxidation agent is based on calcium carbide, aluminum shot, ferrosilicon powder, and addition is according to steel oxygen content in water And make white slag situation and be added in right amount, heating process selects appropriate electric current to be heated according to rhythm is more than needed with temperature conditions, heats Time presses two secondary controls, a heating 8-11min, two heating 7-11min；LF refining uses big quantity of slag slagging process, it is desirable that refining One heating end clinker must bleach or yellowish-white, the white slag retention time >=35min, is required according to slag making feelings in two heating processes Condition adds deoxidier, silicon-calcium wire is added before leaving from station, must shut off argon gas, 1600 ± 15 DEG C of upper steel temperature before adding silicon-calcium wire.It is required that The finishing slag that refining terminates is good fluidity, the suitable foam white slag of viscosity, refining total time requires control in 60min or more.
VD refinery practices：VD vacuum degrees must reach 70Pa hereinafter, preferably 67Pa, and the dwell time is necessary >=22min, breaks It soft blow 2-5min or is not blown after vacuum, molten steel must not be exposed during soft blow, normal to wrap the minute vacuumized online and be：（It takes out true Unprecedented liquid steel temperature-target temperature leaving from station）/ 1.7, ensure that coverture is paved with molten steel face, must shut off argon gas before adding coverture, Upper 1550-1570 DEG C of steel temperature.
Die casting process：Conventional mould pouring temperature is controlled according to 1550-1555 DEG C, and molten steel has to carry out soft blow after arriving at a station Argon technique, argon blowing time control are opened after requirement calmness 5min after 5-10min, Argon and are poured, must assure that after cast Cap mouth heat insulation effect；
Heating process:In heating process, heating speed and heating temperature are controlled, 3-4 hours double steels, are turned over before heat preservation terminates After steel, it is warming up to holding temperature, after remaining soaking time heat preservation, in tapping process, increases gas flow, continues Heating, after tapping, pincers, which are hung, should rest on right over steel rider road, and heating temperature is 700-850 DEG C, and heat up 60-100 per hour DEG C, holding temperature is 1300-1320 DEG C.
Rolling mill practice：Based on roughing, supplemented by finish rolling；Roughing is rolled using percentage pass reduction gradually incremental measure, maximum Percentage pass reduction processed is more than 15%；Rough rolling step：Percentage pass reduction gradually rises, the finish rolling stage：Percentage pass reduction continuously decreases；
The cold technique of heap:Tempering being carried out into burial pit after steel plate rolling and expanding hydrogen technique, car type furnace is then taken to be heated to 500 DEG C And it comes out of the stove after keeping the temperature 96h；
Heat treatment process：It is 830 DEG C, soaking time 13h, red temperature 640-660 first to use normalizing rapid cooling, normalizing temperature ℃；Then it is tempered, temperature is 600 DEG C, soaking time 26h.
Comparative example：
1,1.2311 slabs of 450mm thickness are prepared using above-mentioned processing step, comparative example 1,2 respectively prepares 50 pieces with embodiment, right In the heat treatment process unlike embodiment of ratio 1 and 2, red temperature is different, normalizing rapid cooling technological parameter and hardness test Average value refers to table 1.
1 normalizing rapid cooling technological parameter of table and hardness
Interpretation of result：As it can be seen from table 1 rapid cooling after 450mm 1.2311 normalizings of thickness, the hardness that different cooling velocities obtains is not Together, after embodiment normalizing rapid cooling rear surface hardness and core hardness in target zone, 1 normalizing rapid cooling rear surface of comparative example, Core hardness is higher, and 2 normalizing rapid cooling rear surface of comparative example and core hardness are relatively low.
2,30 blocks of slabs qualified in above-described embodiment are taken to carry out temper, wherein comparative example 3 and 4 and embodiment are not Same is temperature difference, tempering process parameters and hardness test average value, refers to table 2.
2 tempering process parameters of table and hardness
Interpretation of result：By to using different temperature tempering, embodiment after embodiment, comparative example 3,4 steel plate rapid cooling of comparative example Tempering rear surface and core hardness meet technical protocol requirement；Comparative example 3 is tempered rear surface and core hardness is higher；Comparative example 4 It is tempered rear surface and core hardness is relatively low, comparative example 3 and 4 does not meet protocol requirement.The 1.2311 of thickness 450mm use 830 DEG C, 13h is kept the temperature, red 640-660 degrees Celsius and 600 DEG C tempering is returned, keeps the temperature 26h, obtained Brinell hardness is in protocol requirement model In enclosing, hardness result is ideal, achieves the desired results.
To our company by 1.2311 thick present invention production 400mm-1000mm special thick mould steel, extracts each batch and examined It surveys, is provided with high polishing performance, good processability, excellent obdurability, the technology that hardness meets 310-340HB wants It asks, dense structure, flat appearance, flawless, the defects of ultrasonic inspection is pin-free, core, impact resistance, excellent combination property.
Finally illustrate, the above examples are only used to illustrate the technical scheme of the present invention and are not limiting, this field is common Other modifications or equivalent replacement that technical staff makes technical scheme of the present invention, without departing from technical solution of the present invention Spirit and scope, be intended to be within the scope of the claims of the invention.

Claims (7)

1. a kind of 1.2311 slab of special thick mould steel, it is characterised in that：Include the chemical composition of following mass percent：C：0.4% ~0.44%, Si：0.3~0.5%, Mn：1.45~1.55%, P≤0.015%, S≤0.005%, Cr：1.5%~1.7%, Mo：3.5% ~4.5%, V：0.025%-0.035%, other is Fe and relict element.
2. a kind of 1.2311 slab of special thick mould steel as described in claim 1, it is characterised in that：The thickness of the slab is 400-1000mm。
3. a kind of production method of 1.2311 slab of special thick mould steel as claimed in claim 2, technological process are：Molten iron → Converter → LF refining → VD vacuum processings → molding cast → steel ingot cleaning → steel ingot send in the 5h after cleaning out and rolls shove charge → rolling → heap is cold → heat treatment → finishing → outer inspection → storage；It is characterized in that：
KR hot metal pretreatment technologies：The molten iron that arrives at a station must take off preceding slag and take off rear slag, ensure liquid level thickness of slag layer≤22mm, molten iron warp Ensure molten iron S≤0.005% after KR stirring desulphurizations, ensures desulfurization period≤20min, desulfurization temperature drop≤20 DEG C；
Converter smelting process：Enter stove molten iron S≤0.005%, P≤0.015%, molten iron temperature >=1270 DEG C, steel scrap strictly uses excellent Matter leftover pieces, slag making basicity R are controlled by 2.5-4.0, tapping target P≤0.01%, C >=0.4%, S≤0.005%, and tapping temperature is big In or be equal to 1660 DEG C, in tapping process into ladle Si-Al-Ba-Ca, manganeisen, Antaciron and lime, fluorite；
Argon blowing process：Argon station is added at one time aluminum steel, and strong Argon 3min, flow 250-500NL/min, steel are required in argon station Liquid level bore hole diameter control is greater than or equal to 1560 DEG C in 400~500mm, from argon station temperature；
LF refining technique：Whole Argon in refining process, Argon intensity are adjusted according to different links needs, and refining slag is added Material, basicity are controlled by 4.0-6.0, and refinement and deoxidation agent is based on calcium carbide, aluminum shot, ferrosilicon powder, and addition is according to steel oxygen content in water And make white slag situation and be added in right amount, heating process selects appropriate electric current to be heated according to rhythm is more than needed with temperature conditions, heats Time presses two secondary controls, a heating 8-11min, two heating 7-11min；
VD refinery practices：VD vacuum degrees must reach 70Pa hereinafter, the dwell time it is necessary >=22min, soft blow 2- after vacuum breaker 5min is not blown, and molten steel must not be exposed during soft blow, normal to wrap the minute vacuumized online and be：（Molten steel temperature before vacuumizing Degree-target temperature leaving from station）/1.7；
Die casting process：Conventional mould pouring temperature is controlled according to 1550-1555 DEG C, and molten steel has to carry out soft blow argon work after arriving at a station Skill, argon blowing time control are opened after requirement calmness 5min after 5-10min, Argon and are poured, and cap mouth is must assure that after cast Heat insulation effect；
Heating process:In heating process, heating speed and heating temperature are controlled, 3-4 hours double steels, are turned over before heat preservation terminates After steel, it is warming up to holding temperature, after remaining soaking time heat preservation, in tapping process, increases gas flow, continues Heating, after tapping, pincers, which are hung, should rest on right over steel rider road；
Rolling mill practice：Based on roughing, supplemented by finish rolling；Roughing is using percentage pass reduction gradually incremental measure, maximum rolling road Secondary reduction ratio is more than 15%；Rough rolling step：Percentage pass reduction gradually rises, the finish rolling stage：Percentage pass reduction continuously decreases；
The cold technique of heap:Tempering being carried out into burial pit after steel plate rolling and expanding hydrogen technique, car type furnace is then taken to be heated to 500 DEG C And it comes out of the stove after keeping the temperature 96h；
Heat treatment process：It is 830 DEG C, soaking time 13h, red temperature 640-660 first to use normalizing rapid cooling, normalizing temperature ℃；Then it is tempered, temperature is 600 DEG C, soaking time 26h.
4. a kind of production method of 1.2311 slab of special thick mould steel as claimed in claim 3, it is characterised in that：The converter In smelting process, preceding slag tapping is kept off with floating plug before tapping, taps and uses slag retaining cone pushing off the slag before terminating, guarantee thickness of slag layer≤ 30mm requires whole Argon in converter tapping process.
5. a kind of production method of 1.2311 slab of special thick mould steel as claimed in claim 3, it is characterised in that：The LF essences It requires, according to slag making situation, to add deoxidier, silicon-calcium wire is added before leaving from station, adds silico-calcium in sweetening process, in two heating process It must shut off argon gas, 1600 ± 15 DEG C of upper steel temperature before line.
6. a kind of production method of 1.2311 slab of special thick mould steel as claimed in claim 3, it is characterised in that：The VD essences In sweetening process, ensure that coverture is paved with molten steel face, must shut off argon gas, upper 1550-1570 DEG C of steel temperature before adding coverture.
7. a kind of production method of 1.2311 slab of special thick mould steel as claimed in claim 3, it is characterised in that：The heating In technique, heating temperature is 700-850 DEG C, is heated up 60-100 DEG C per hour, and holding temperature is 1300-1320 DEG C.
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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN114427065A (en) * 2021-12-28 2022-05-03 南阳汉冶特钢有限公司 Production method of 250-400mm thick high-quality low-cost plastic mold steel 1.2738
CN114645573A (en) * 2022-03-23 2022-06-21 福建众合开发建筑设计院有限公司 Fireproof and sound-proof steel structure building material and preparation method thereof

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1422972A (en) * 2002-12-18 2003-06-11 江汉石油钻头股份有限公司 High-strength alloy tool steel
CN103160740A (en) * 2013-03-16 2013-06-19 南阳汉冶特钢有限公司 Steel 18MnMoNbR for pressure vessel and process for producing 18MnMoNbR steel plate with thickness of 100mm

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1422972A (en) * 2002-12-18 2003-06-11 江汉石油钻头股份有限公司 High-strength alloy tool steel
CN103160740A (en) * 2013-03-16 2013-06-19 南阳汉冶特钢有限公司 Steel 18MnMoNbR for pressure vessel and process for producing 18MnMoNbR steel plate with thickness of 100mm

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN114427065A (en) * 2021-12-28 2022-05-03 南阳汉冶特钢有限公司 Production method of 250-400mm thick high-quality low-cost plastic mold steel 1.2738
CN114645573A (en) * 2022-03-23 2022-06-21 福建众合开发建筑设计院有限公司 Fireproof and sound-proof steel structure building material and preparation method thereof

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