CN108504935A - Containing V, N Micro Alloying pre-hardened plastic mold steel and preparation method thereof - Google Patents

Containing V, N Micro Alloying pre-hardened plastic mold steel and preparation method thereof Download PDF

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CN108504935A
CN108504935A CN201810447871.6A CN201810447871A CN108504935A CN 108504935 A CN108504935 A CN 108504935A CN 201810447871 A CN201810447871 A CN 201810447871A CN 108504935 A CN108504935 A CN 108504935A
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steel
alloys
temperature
preparation
converter
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柯晓涛
邓通武
冉准
胡峰荣
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Pangang Group Panzhihua Iron and Steel Research Institute Co Ltd
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Pangang Group Panzhihua Iron and Steel Research Institute Co Ltd
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    • CCHEMISTRY; METALLURGY
    • C22METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22CALLOYS
    • C22C38/00Ferrous alloys, e.g. steel alloys
    • C22C38/02Ferrous alloys, e.g. steel alloys containing silicon
    • CCHEMISTRY; METALLURGY
    • C21METALLURGY OF IRON
    • C21DMODIFYING 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
    • C21D8/00Modifying the physical properties by deformation combined with, or followed by, heat treatment
    • C21D8/005Modifying the physical properties by deformation combined with, or followed by, heat treatment of ferrous alloys
    • CCHEMISTRY; METALLURGY
    • C22METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22CALLOYS
    • C22C33/00Making ferrous alloys
    • C22C33/04Making ferrous alloys by melting
    • C22C33/06Making ferrous alloys by melting using master alloys
    • CCHEMISTRY; METALLURGY
    • C22METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22CALLOYS
    • C22C38/00Ferrous alloys, e.g. steel alloys
    • C22C38/001Ferrous alloys, e.g. steel alloys containing N
    • CCHEMISTRY; METALLURGY
    • C22METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22CALLOYS
    • C22C38/00Ferrous alloys, e.g. steel alloys
    • C22C38/04Ferrous alloys, e.g. steel alloys containing manganese
    • CCHEMISTRY; METALLURGY
    • C22METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22CALLOYS
    • C22C38/00Ferrous alloys, e.g. steel alloys
    • C22C38/06Ferrous alloys, e.g. steel alloys containing aluminium
    • CCHEMISTRY; METALLURGY
    • C22METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22CALLOYS
    • C22C38/00Ferrous alloys, e.g. steel alloys
    • C22C38/18Ferrous alloys, e.g. steel alloys containing chromium
    • C22C38/40Ferrous alloys, e.g. steel alloys containing chromium with nickel
    • C22C38/42Ferrous alloys, e.g. steel alloys containing chromium with nickel with copper
    • CCHEMISTRY; METALLURGY
    • C22METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22CALLOYS
    • C22C38/00Ferrous alloys, e.g. steel alloys
    • C22C38/18Ferrous alloys, e.g. steel alloys containing chromium
    • C22C38/40Ferrous alloys, e.g. steel alloys containing chromium with nickel
    • C22C38/44Ferrous alloys, e.g. steel alloys containing chromium with nickel with molybdenum or tungsten
    • CCHEMISTRY; METALLURGY
    • C22METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22CALLOYS
    • C22C38/00Ferrous alloys, e.g. steel alloys
    • C22C38/18Ferrous alloys, e.g. steel alloys containing chromium
    • C22C38/40Ferrous alloys, e.g. steel alloys containing chromium with nickel
    • C22C38/46Ferrous alloys, e.g. steel alloys containing chromium with nickel with vanadium
    • YGENERAL 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
    • Y02TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02PCLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
    • Y02P10/00Technologies related to metal processing
    • Y02P10/20Recycling

Abstract

The present invention relates to containing V, N Micro Alloying pre-hardened plastic mold steel and preparation method thereof, belong to field of steel metallurgy.The technical problem to be solved is that existing pre-hardened plastic mold steel production cost is high and the quenching and tempering type plastic die steel production cycle is long, there is provided containing V, N Micro Alloying pre-hardened plastic mold steel, chemical composition is technical solution:By weight percentage, C 0.45~0.52%, Si 0.30~0.60%, Mn 1.20~1.50%, P≤0.030%, S≤0.030%, Cr 0.20~0.40%, V 0.12~0.18%, N 0.0080~0.0120%, Als 0.015~0.050%, Mo≤0.03%, Ni≤0.30%, Cu≤0.25%, surplus Fe.

Description

Containing V, N Micro Alloying pre-hardened plastic mold steel and preparation method thereof
Technical field
The present invention relates to containing V, N Micro Alloying pre-hardened plastic mold steel and preparation method thereof, belong to field of steel metallurgy.
Background technology
Plastic die steel be on active service when due to bear larger pressure, bending force, impact force and frictional force etc., To the more demanding of its comprehensive mechanical property, there are higher hardness, intensity and wearability and enough toughness.
Quenching and tempering type plastic die steel by quenching, reheating process, can make mould steel have hardness uniformly, processability Can and the advantages that mechanical property is good, die deformation is small, however, it may appear that the defects of being heat-treated the deformation brought, cracking, decarburization, But also it can extend manufacture cycle.In contrast, Micro Alloying pre-hardened plastic mold steel be not required to be quenched, temper, warp It is air-cooled after forging or rolling to directly reach required quenching and tempering hardness, it not only avoids various caused by being heat-treated again after processing Defect, improves the making precision of mold, while can also shorten fabrication cycle.
Current most popular pre-hardened plastic mold steel is mainly P20 (national standard trade mark 3Cr2Mo) and 718 (state's labels Number 3Cr2NiMo) steel.P20 is the CrMo steel containing (1.40%~2.00%) Cr, (0.30%~0.52%) Mo, and 718 be in P20 On the basis of add (0.80%~1.20%) Ni high performance plastics mould steel.However, the above steel grade be both needed to addition content it is higher The expensive alloying elements such as Mo, Cr just can guarantee that the mechanical property of mould steel, production cost are higher.
Invention content
The purpose of the present invention is to provide containing V, N Micro Alloying pre-hardened plastic mold steel and preparation method thereof, showed with solution The problem of some pre-hardened plastic mold steel production cost height and quenching and tempering type plastic die steel production cycle length.
The present invention provides containing V, N Micro Alloying pre-hardened plastic mold steel, chemical composition is:By weight percentage, C:0.45%~0.52%, Si:0.30%~0.60%, Mn:1.20%~1.50%, P≤0.030%, S≤0.030%, Cr:0.20%~0.40%, V:0.12%~0.18%, N:0.0080%~0.0120%, Als:0.015%~0.050%, Mo≤0.03%, Ni≤0.30%, Cu≤0.25%, surplus Fe.
Further, the Micro Alloying pre-hardened plastic mold steel, chemical composition comprises the following components in percentage by weight, meet with It is at least one of lower:P content is 0.015%~0.016%;S contents are 0.010%~0.013%;Als contents be 0.026%~ 0.034%;Mo contents are 0.001%;Ni contents are 0.01%;Cu contents are 0.03%.
The present invention provides the preparation methods of the Micro Alloying pre-hardened plastic mold steel, include the following steps:Converter smelting It refines, inert gas is blown into after Converter, LF stoves refine, RH application of vacuum, and steel billet is made in continuous casting, and heating steel billet, rolling are become a useful person, cold But to get.
Further, the heating steel billet, rolling become a useful person step meet it is at least one of following:
Billet heating temperature is 950~1250 DEG C;
Preferably, billet heating temperature is 1200~1247 DEG C;
Soaking temperature is 1150~1200 DEG C;
Heating and soaking total time are 120~210min.
Wherein, soaking temperature need to be controlled at 1150 DEG C or more, just be can ensure that and rolled in austenite one phase area;In addition, casting In base heating process, temperature is higher, then autstenitic grain size is about coarse, unfavorable to the structure property of finished product, and the present invention limits equal The upper limit of hot temperature just can guarantee the structure property of finished product no more than 1200 DEG C.
Wherein, heating needed just to can ensure that strand center portion is consistent with surface temperature in 120~210min with soaking total time, Otherwise temperature gradient is excessive, then is unfavorable for the structure property control of finished product.
Further, band steel is rolled into using band steel rolling line.
Further, the cooling step meets at least one of following:
The cold middle one or more of modes of natural air cooling, air-cooled, water cooling, mist are taken to be cooled down;
Cooling velocity is controlled in 1.00~1.50 DEG C/s;
It is collected when being cooled to 650 DEG C or less, later natural air cooling;
Preferably, it is collected when being cooled to 508~642 DEG C.
Further, the type of cooling is chosen according to the thickness of band steel.
Wherein, the tissue and property of plastic die steel needs could be obtained in 1.00~1.50 DEG C/s by cooling velocity being controlled Can, otherwise tissue abnormalities and performance can be caused not to conform to.
Wherein, if be collected when temperature is higher than 650 DEG C, the cooling velocity of steel can be caused slack-off, to influence steel Tissue and performance, cause mechanical property not conform to;Less than the temperature collection, then there is no problem, and cooling procedure hereafter does not influence steel Tissue and performance.
Further, the converter smelting step meets at least one of following:
Molten iron and steel scrap are added in converter, enters stove S content≤0.060%;
After converter is added in molten iron and steel scrap, C is taken off by Converter Oxigen Blowing, molten iron and steel scrap are just smelt molten steel, when molten steel at C is arrived in refining at the beginning of point:0.05%~0.20%, P≤0.025%, S≤0.025%, and tapping temperature be not less than 1650 DEG C when tapping arrive In ladle;
Preferably, tapping temperature is 1650~1690 DEG C;
FeSi alloys, FeMn alloys, FeCr alloys, carburant and FeV alloys or VN alloys, control are added in tapping process C processed in 0.40%~0.45% range, Si in 0.35%~0.52% range, Mn in 1.25%~1.45% range, Cr is in 0.25%~0.35% range, and V is in 0.12%~0.18% range;Alternatively, replacing FeSi using FeSiMn alloys Alloy and FeMn alloys;
Preferably, the carburant is C powder or anthracite;
It is initially added into FeSi alloys, FeMn alloys, FeCr alloys and FeV alloys or VN alloys in tapping 1/3, is tapped It is added before to 2/3.
Wherein, it controls into stove sulfur content≤0.060%, just can guarantee the requirement that finished product sulfur content reaches≤0.030%, it is no It then needs to carry out desulfurization by LF stoves, not only increases cost, but also extend refining time, cannot ensure to smelt and continuous casting rhythm Matching.
Wherein, the just control of steel-making water constituent:C:If oxygen activity of the control in < 0.05% in steel is higher, and fluctuates Larger, about in 50~1200ppm, follow-up refining is difficult to control, and deoxidation cost is higher;If C content > 0.20%, due to Liquid steel temperature in converter is so that strong heating element C, Si in molten steel etc. is generated heat by oxidation, to improve steel by oxygen blast Coolant-temperature gage, if terminal C content is too high, the temperature of molten steel cannot meet tapping and require;P:It is oxidizing atmosphere, P in converter Occur oxidation reaction with the oxygen that is blown into, oxidation product adsorbs to achieve the purpose that de- P by slag charge, and in follow-up LF refining and It is reducing atmosphere during RH application of vacuum, in ladle, the P in vessel slag of the part containing high P that when tapping brings into is reduced And be again introduced into steel, to cause finished product P to runaway (P≤0.030%), therefore, it is necessary to control the P of just steel-making water Content is not more than 0.025%;S:If just S contents are more than 0.025% in steel-making water, finished product S contents are be easy to cause beyond control Range (S≤0.030%), and S is easy to form sulphide inculsion in steel, it is totally unfavorable to the service life of mold.
Wherein, tapping temperature control is >=1650 DEG C, just can ensure that molten steel will not solidify before reaching LF stoves.If warm Degree controls excessively high, then needs converter depth oxygen blast, is unfavorable for the control of cost and aim carbon, therefore preferably tapping temperature is 1650 ~1690 DEG C.
Wherein, alloy is added in tapping process, the content range of each ingredient of control is committed step:It is sent out in production practices Existing, if the upper limit value beyond above-mentioned restriction, finished product ingredient is easy to exceed the upper limit;If alloy is added very little when converter tapping, Cause each component content to be less than the lower limiting value of above-mentioned restriction, whens RH stove trimmings, will need to be added a large amount of alloys, ingredient it is equal It even property and pours steel temperature (the big molten steel temperature drop of alloy amount is also big) and is difficult to ensure, and usually all contain more impurity member in alloy A large amount of alloys are added in element at this time, and subsequently without refining measure, the impurity element in alloy is difficult to remove, and is unfavorable for degree of purity Control.
Wherein, it is initially added into FeSi alloys, FeMn alloys, FeCr alloys and FeV alloys in tapping 1/3 or VN is closed Gold adds before tapping to 2/3, is conducive to the abundant fusing of alloy and is evenly distributed in molten steel.If it is too early that alloy is added, It is difficult to ensure alloy rapid melting;It is added too late, alloy rests on molten steel surface, is unfavorable for the fusing of alloy and is uniformly distributed.
Further, at least one of inert gas step satisfaction or less is blown into after the Converter:
The inert gas is argon gas or nitrogen;
It is blown into time >=2min of inert gas;
Preferably, it is blown into time >=4min of inert gas;
Aluminum steel is fed when being blown into inert gas, pre-deoxidation is carried out to molten steel;
Preferably, aluminum steel is fed according to molten steel oxygen activity, molten steel oxygen activity is reduced by the pure Al of ton steel feeding 0.0015kg 1ppm is controlled, by the control of molten steel oxygen activity within 30ppm.
Wherein, the blowing time of inert gas is not less than 2min, can ensure that molten steel has enough circulation time, can be with Make all kinds of alloys of addition fully melt and uniformly.
Further, the LF stoves refinement step meets at least one of following:
The refining of LF stoves uses electrical heating;
Liquid steel temperature is 1556~1596 DEG C.
Wherein, control liquid steel temperature be 1556~1596 DEG C, it can be ensured that when pouring steel molten steel overheat 20~50 DEG C it Between, being smoothed out for steel is poured in guarantee.
Further, the RH application of vacuum step meets at least one of following:
Vacuum processing time >=12min;
Preferably, vacuum processing time is 13~19min;
The processing time of vacuum degree≤3mbar >=10min;
Preferably, the processing time of vacuum degree≤3mbar is 10~14min;
After vacuum degree≤3mbar processing, nitrogenous core-spun yarn is fed in ladle, it is 0.0080% to control N content in molten steel ~0.0120%.
Wherein, when vacuum degree reaches 3mbar or less, could effectively deviate from molten steel [H];Ensure vacuum degree≤3mbar's Processing time >=10min could control [H] in molten steel within 2.0ppm.
Further, the continuous casting step meets at least one of following:
Tundish temperature is 1496~1536 DEG C;
Preferably, tundish temperature is 1508~1515 DEG C;
Slab cooling is to room temperature.
The liquidus temperature of steel grade of the present invention is about 1476~1486 DEG C, and control tundish temperature is higher than the liquidus temperature of steel 20 DEG C or more, it can be ensured that molten steel will not solidify in ladle, it is ensured that pour steel and be smoothed out;When the degree of superheat is more than 50 DEG C, casting Base center porosity and centre burst are more serious, and center porosity possibly even reaches 3.0 grades or more, and generate a large amount of middle heart shake The defects of line and shrinkage cavity, therefore, the upper limit for controlling the degree of superheat is 50 DEG C, can ensure slab quality.
The present invention provides containing V, N Micro Alloying pre-hardened plastic mold steel, mainly has the following advantages:
1, pre- compared to existing under the premise of ensureing mechanical property needed for mould steel using V, N microalloying mode The usage amount of precious metal element Mo, Cr can be greatly decreased in gravity die plastic die steel, significantly reduce production cost.
2, it is not necessarily to modifier treatment, it is main to optimize soaking temperature, total heating time and cooling velocity after rolling etc. in the operation of rolling Parameter can reach pre-hardening effect by online controlled rolling and controlled cooling, and operating method is simple, with short production cycle, and avoids The problems such as being processed into the heat-treatment distortion after mold.
3, the plastic die steel hardness that the present invention is prepared can control into 28~36HRC, disclosure satisfy that market Requirement to pre-hardened plastic mold steel is suitble to promote and apply in the industrial production.
Specific implementation mode
The raw material that is used in the specific embodiment of the invention, equipment are known product, pass through and buy commercial product and obtain.
The present invention provides containing V, N Micro Alloying pre-hardened plastic mold steel, chemical composition is:By weight percentage, C:0.45%~0.52%, Si:0.30%~0.60%, Mn:1.20%~1.50%, P≤0.030%, S≤0.030%, Cr:0.20%~0.40%, V:0.12%~0.18%, N:0.0080%~0.0120%, Als:0.015%~0.050%, Mo≤0.03%, Ni≤0.30%, Cu≤0.25%, surplus Fe.
Plastic die steel of the present invention is by adding alloying component V:0.10%~0.15%, N:0.0080%~ 0.0120%, the usage amount of precious metal element Mo, Cr is greatly reduced, and it is 28~36HRC's that hardness, which can be prepared, Plastic die steel.
Wherein, 0.10%~0.15% V is added, primarily to giving full play to its precipitation strength and crystal grain thinning work With steel being made to keep fine grain structure, to ensure that steel has the matching of good obdurability and high hardness, to improve mold Service life.
0.0080%~0.0120% N is added, can by and V combination, in steel from austenite to ferrite, pearly-lustre In body transition processes, more tiny, disperse VN particles are precipitated, further strengthen the effect of the precipitation strength and crystal grain thinning of V, Steel is set to obtain better intensity and toughness plasticity.
In addition, the chemical composition of plastic die steel of the present invention also contains Cr:0.20%~0.40%, Cr are to effectively improve steel Quenching degree, tensile strength and hardness one of element, therefore, be added 0.20%~0.40% Cr primarily to improve steel In the comprehensive performance after line Pre-hardening treatment.
Further, the present invention optimizes the parameters such as soaking temperature, total heating time and cooling velocity after rolling in the operation of rolling, Pre-hardening effect is can reach by online controlled rolling and controlled cooling, without carrying out modifier treatment.
The preparation of 1 Micro Alloying pre-hardened plastic mold steel of the present invention of embodiment
The technology of the present invention is used on 120 tons of (practical tap is within the scope of 120~140 tons) bof processes of nominal capacity The Micro Alloying pre-hardened plastic mold steel containing V, N is produced, production technology is smart to be blown into inert gas → LF stoves after converter smelting → stove The machine 4 of refining → RH application of vacuum → 4 flows billet caster and is cast into 360mm × 450mm steel billets → heating steel billet → band steel rolling life Producing line is rolled into 10~100mm (thickness) × 400~500mm (width) → and rolls rear online Pre-hardening treatment.
125 tons of molten iron and 20 tons of steel scraps are added first in converter, it is 0.047% to enter stove S contents, and molten iron and steel scrap are added After converter, the function of C is taken off using Converter Oxigen Blowing, molten iron and steel scrap are just smelt molten steel, when molten steel composition is just refined to 0.08% C, 0.014% P, 0.009% S, tapping is in ladle when temperature is 1677 DEG C, and practical tap is 134 tons of (converters at this time About 5% raw material is burnt in smelting process).Tap 1/3 when start that FeSi alloys, FeMn alloys, FeCr are added into molten steel Alloy, FeV alloys and anthracite carry out Si, Mn, Cr, V and C element alloying, are added before tapping 2/3, wherein the FeSi being added Si contents are that Mn contents are that Cr contents are that V contains in 54%, FeV alloys in 82%, FeCr alloys in 74%, FeMn alloys in alloy Amount is 78%, and it is 92% that C is fixed in anthracite, and C content is 0.42% in control molten steel, Si contents are that 0.43%, Mn contents are 1.28%, Cr content is 0.27%, V content 0.13%.
After molten steel arrival stove after chain-wales, steel ladle immediately accesses pipeline, and the molten steel into ladle is blown into argon gas, is blown into argon 200m aluminum steels are fed using the method for line feeding after gas 4min, by the control of molten steel oxygen activity within 30ppm.
After molten steel reaches LF stoves, connects argon gas pipeline and be blown into argon gas, and be electrically heated, liquid steel temperature reaches 1576 DEG C When, molten steel is sent to RH processes and is vacuum-treated.
After molten steel reaches RH processes, it is vacuum-treated, vacuum processing time 19min, wherein vacuum degree≤3mbar's When processing time is 14min, trimming is carried out, and feed core-spun yarn containing N, the N content in steel is controlled 0.0080%~ 0.0120%, then molten steel is sent to conticaster and is cast.
It being cast into 360mm × 450mm strands on 4 machines 4 stream billet caster, tundish temperature is 1515 DEG C when continuous casting, The liquidus temperature of steel is 1482 DEG C, packet sampling analysis molten steel chemical constituent is 0.45% in conticaster C, 0.32% Si, 1.21% Mn, 0.016% P, 0.011% S, 0.20% Cr, 0.13% V%, 0.0085% N, 0.026% Als, 0.001% Mo, 0.01% Ni, 0.03% Cu, surplus are Fe and inevitable impurity.Strand Stacking cooled to room temperature.
It is sent after slab cooling to band steel rolling line and is heated, rolled, rolling specs are 10mm (thickness) × 410mm The band steel of (width).Billet heating temperature control is 1247 DEG C, and soaking temperature control is 1193 DEG C, heating and soaking total time 204min;Rear natural air cooling is rolled, cooling velocity is 1.0 DEG C/s, is collected when being cooled to 642 DEG C, later stacking natural air cooling.
The Hardness Surveillance result of steel is 35HRC;Mechanical properties test result:Rel is 624.3Mpa, Rm 889.7Mpa, A For 43.4%, Aku (room temperature) 34.4J;The tissue of steel is ferrite+pearlite;The decarburized layer deepness measurement result of steel is 0.44mm;The non-metallic inclusion rating result of steel be A classes be carefully 1.0 grades, A classes are slightly 0.5 grade, B classes are carefully 0.5 grade, B classes are thick It it is 0 grade, C classes are carefully 0 grade, C classes are slightly 0 grade, D classes are carefully 0 grade, D classes are slightly 0 grade, Ds classes are 0 grade.
The preparation of 2 Micro Alloying pre-hardened plastic mold steel of the present invention of embodiment
The technology of the present invention is used on 120 tons of (practical tap is within the scope of 120~140 tons) bof processes of nominal capacity The Micro Alloying pre-hardened plastic mold steel containing V, N is produced, production technology is smart to be blown into inert gas → LF stoves after converter smelting → stove The machine 4 of refining → RH application of vacuum → 4 flows billet caster and is cast into 360mm × 450mm steel billets → heating steel billet → band steel rolling life Producing line is rolled into 10~100mm (thickness) × 400~500mm (width) → and rolls rear online Pre-hardening treatment.
122 tons of molten iron and 20 tons of steel scraps are added first in converter, it is 0.050% to enter stove S contents, and molten iron and steel scrap are added After converter, the function of C is taken off using Converter Oxigen Blowing, molten iron and steel scrap are just smelt molten steel, when molten steel composition is just refined to 0.13% C, 0.015% P, 0.011% S, tapping is in ladle when temperature is 1682 DEG C, and practical tap is 131 tons of (converters at this time About 5% raw material is burnt in smelting process).Tap 1/3 when start that FeSi alloys, FeMn alloys, FeCr are added into molten steel Alloy, FeV alloys and anthracite carry out Si, Mn, Cr, V and C element alloying, are added before tapping 2/3, wherein the FeSi being added Si contents are that Mn contents are that Cr contents are that V contains in 54%, FeV alloys in 82%, FeCr alloys in 74%, FeMn alloys in alloy Amount is 78%, and it is 92% that C is fixed in anthracite, and C content is 0.45% in control molten steel, Si contents are that 0.42%, Mn contents are 1.36%, Cr content is 0.27%, V content 0.18%.
After molten steel arrival stove after chain-wales, steel ladle immediately accesses pipeline, and the molten steel into ladle is blown into argon gas, is blown into argon 200m aluminum steels are fed using the method for line feeding after gas 4min, by the control of molten steel oxygen activity within 30ppm.
After molten steel reaches LF stoves, connects argon gas pipeline and be blown into argon gas, and be electrically heated, liquid steel temperature reaches 1574 DEG C When, molten steel is sent to RH processes and is vacuum-treated.
After molten steel reaches RH processes, it is vacuum-treated, vacuum processing time 13min, wherein vacuum degree≤3mbar's When processing time is 10min, carry out trimming, and feed core-spun yarn containing N, control the N content in steel for 0.0080%~ 0.0120%, then molten steel is sent to conticaster and is cast.
It being cast into 360mm × 450mm strands on 4 machines 4 stream billet caster, tundish temperature is 1511 DEG C when continuous casting, The liquidus temperature of steel is 1482 DEG C, packet sampling analysis molten steel chemical constituent is 0.51% in conticaster C, 0.59% Si, 1.48% Mn, 0.015% P, 0.010% S, 0.37% Cr, 0.18% V%, 0.0118% N, 0.034% Als, 0.001% Mo, 0.01% Ni, 0.03% Cu, surplus are Fe and inevitable impurity.Strand Stacking cooled to room temperature.
It is sent after slab cooling to band steel rolling line and is heated, rolled, rolling specs are 100mm (thickness) × 500mm The band steel of (width).Billet heating temperature control is 1200 DEG C, and soaking temperature control is 1158 DEG C, heating and soaking total time 121min;Online Pre-hardening treatment is carried out by wearing water+misting cooling mode after rolling, the surface cooling velocity of steel is 1.4 DEG C/s, It is collected when being cooled to 508 DEG C, later stacking natural air cooling.
The Hardness Surveillance result of steel is 29HRC;Mechanical properties test result:Rel is 695.6Mpa, Rm 987.1Mpa, A For 37.0%, Aku (room temperature) 23.8J;The tissue of steel is ferrite+pearlite;The decarburized layer deepness measurement result of steel is 0.37mm;The non-metallic inclusion rating result of steel be A classes be carefully 1.0 grades, A classes are slightly 0 grade, B classes are carefully 0.5 grade, B classes are slightly 0.5 grade, C classes be carefully 0 grade, C classes are slightly 0 grade, D classes are carefully 0 grade, D classes are slightly 0 grade, Ds classes are 0 grade.
The preparation of 3 Micro Alloying pre-hardened plastic mold steel of the present invention of embodiment
The technology of the present invention is used on 120 tons of (practical tap is within the scope of 120~140 tons) bof processes of nominal capacity The Micro Alloying pre-hardened plastic mold steel containing V, N is produced, production technology is smart to be blown into inert gas → LF stoves after converter smelting → stove The machine 4 of refining → RH application of vacuum → 4 flows billet caster and is cast into 360mm × 450mm steel billets → heating steel billet → band steel rolling life Producing line is rolled into 10~100mm (thickness) × 400~500mm (width) → and rolls rear online Pre-hardening treatment.
128 tons of molten iron and 20 tons of steel scraps are added first in converter, it is 0.041% to enter stove S contents, and molten iron and steel scrap are added After converter, the function of C is taken off using Converter Oxigen Blowing, molten iron and steel scrap are just smelt molten steel, when molten steel composition is just refined to 0.17% C, 0.018% P, 0.011% S, tapping is in ladle when temperature is 1681 DEG C, and practical tap is 136 tons of (converters at this time About 5% raw material is burnt in smelting process).Tap 1/3 when start that FeSi alloys, FeMn alloys, FeCr are added into molten steel Alloy, FeV alloys and anthracite carry out Si, Mn, Cr, V and C element alloying, are added before tapping 2/3, wherein the FeSi being added Si contents are that Mn contents are that Cr contents are that V contains in 54%, FeV alloys in 82%, FeCr alloys in 74%, FeMn alloys in alloy Amount is 78%, and it is 92% that C is fixed in anthracite, and C content is 0.42% in control molten steel, Si contents are that 0.46%, Mn contents are 1.37%, Cr content is 0.29%, V content 0.16%.
After molten steel arrival stove after chain-wales, steel ladle immediately accesses pipeline, and the molten steel into ladle is blown into argon gas, is blown into argon 200m aluminum steels are fed using the method for line feeding after gas 4min, by the control of molten steel oxygen activity within 30ppm.
After molten steel reaches LF stoves, connects argon gas pipeline and be blown into argon gas, and be electrically heated, liquid steel temperature reaches 1577 DEG C When, molten steel is sent to RH processes and is vacuum-treated.
After molten steel reaches RH processes, it is vacuum-treated, vacuum processing time 14min, wherein vacuum degree≤3mbar's When processing time is 11min, carry out trimming, and feed core-spun yarn containing N, control the N content in steel for 0.0080%~ 0.0120%, then molten steel is sent to conticaster and is cast.
It being cast into 360mm × 450mm strands on 4 machines 4 stream billet caster, tundish temperature is 1508 DEG C when continuous casting, The liquidus temperature of steel is 1482 DEG C, packet sampling analysis molten steel chemical constituent is 0.47% in conticaster C, 0.47% Si, 1.35% Mn, 0.016% P, 0.013% S, 0.28% Cr, 0.16% V%, 0.0102% N, 0.034% Als, 0.001% Mo, 0.01% Ni, 0.03% Cu, surplus are Fe and inevitable impurity.Strand Stacking cooled to room temperature.
It is sent after slab cooling to band steel rolling line and is heated, rolled, rolling specs are 60mm (thickness) × 455mm The band steel of (width).Billet heating temperature control is 1219 DEG C, and soaking temperature control is 1198 DEG C, heating and soaking total time 169min;Online Pre-hardening treatment is carried out by spraying+air cooling way after rolling, the surface cooling velocity of steel is 1.2 DEG C/s, is cooled to It is collected at 603 DEG C, later stacking natural air cooling.
The Hardness Surveillance result of steel is 32HRC;Mechanical properties test result:Rel is 659.8Mpa, Rm 947.7Mpa, A For 39.4%, Aku (room temperature) 29.1J;The tissue of steel is ferrite+pearlite;The decarburized layer deepness measurement result of steel is 0.44mm;The non-metallic inclusion rating result of steel be A classes be carefully 0.5 grade, A classes are slightly 0.5 grade, B classes are carefully 0.5 grade, B classes are thick It it is 0 grade, C classes are carefully 0 grade, C classes are slightly 0 grade, D classes are carefully 0 grade, D classes are slightly 0 grade, Ds classes are 0 grade.

Claims (10)

1. the Micro Alloying pre-hardened plastic mold steel containing V, N, it is characterized in that:Its chemical composition is:By weight percentage, C: 0.45%~0.52%, Si:0.30%~0.60%, Mn:1.20%~1.50%, P≤0.030%, S≤0.030%, Cr: 0.20%~0.40%, V:0.12%~0.18%, N:0.0080%~0.0120%, Als:0.015%~0.050%, Mo ≤ 0.03%, Ni≤0.30%, Cu≤0.25%, surplus Fe.
2. Micro Alloying pre-hardened plastic mold steel as described in claim 1, it is characterized in that:Its chemical composition is by weight percentage Meter meets at least one of following:P content is 0.015%~0.016%;S contents are 0.010%~0.013%;Als contents are 0.026%~0.034%;Mo contents are 0.001%;Ni contents are 0.01%;Cu contents are 0.03%.
3. the preparation method of Micro Alloying pre-hardened plastic mold steel described in claims 1 or 2, it is characterized in that:Include the following steps: Converter smelting, inert gas, the refining of LF stoves are blown into after Converter, and steel billet, heating steel billet, rolling is made in RH application of vacuum, continuous casting Become a useful person, it is cooling to get.
4. preparation method as claimed in claim 3, it is characterized in that:The heating steel billet, rolling become a useful person step meet with down toward One item missing:
Billet heating temperature is 950~1250 DEG C;
Preferably, billet heating temperature is 1200~1247 DEG C;
Soaking temperature is 1150~1200 DEG C;
Heating and soaking total time are 120~210min.
5. preparation method as claimed in claim 3, it is characterized in that:The cooling step meets at least one of following:
The cold middle one or more of modes of natural air cooling, air-cooled, water cooling, mist are taken to be cooled down;
Cooling velocity is controlled in 1.00~1.50 DEG C/s;
It is collected when being cooled to 650 DEG C or less, later natural air cooling;
Preferably, it is collected when being cooled to 508~642 DEG C.
6. preparation method as claimed in claim 3, it is characterized in that:The converter smelting step meets at least one of following:
Molten iron and steel scrap are added in converter, enters stove S content≤0.060%;
After converter is added in molten iron and steel scrap, C is taken off by Converter Oxigen Blowing, molten iron and steel scrap are just smelt molten steel, at the beginning of molten steel composition Refine C:0.05%~0.20%, P≤0.025%, S≤0.025%, and when tapping temperature is not less than 1650 DEG C tapping to ladle In;
Preferably, tapping temperature is 1650~1690 DEG C;
FeSi alloys, FeMn alloys, FeCr alloys, carburant and FeV alloys or VN alloys are added in tapping process, controls C In 0.40%~0.45% range, Si is in 0.35%~0.52% range, and in 1.25%~1.45% range, Cr's Mn exists In 0.25%~0.35% range, V is in 0.12%~0.18% range;Alternatively, replacing FeSi alloys using FeSiMn alloys With FeMn alloys;
Preferably, the carburant is C powder or anthracite;
FeSi alloys, FeMn alloys, FeCr alloys and FeV alloys or VN alloys, tapping to 2/ are initially added into tapping 1/3 It is added before 3.
7. preparation method as claimed in claim 3, it is characterized in that:It is following that inert gas step satisfaction is blown into after the Converter At least one of:
The inert gas is argon gas or nitrogen;
It is blown into time >=2min of inert gas;
Preferably, it is blown into time >=4min of inert gas;
Aluminum steel is fed when being blown into inert gas, pre-deoxidation is carried out to molten steel;
Preferably, aluminum steel is fed according to molten steel oxygen activity, by ton steel feeding 0.0015kg pure Al reduction molten steel oxygen activity 1ppm into Row control, by the control of molten steel oxygen activity within 30ppm.
8. preparation method as claimed in claim 3, it is characterized in that:The LF stoves refinement step meets at least one of following:
The refining of LF stoves uses electrical heating;
Liquid steel temperature is 1556~1596 DEG C.
9. preparation method as claimed in claim 3, it is characterized in that:The RH application of vacuum step meets at least one of following:
Vacuum processing time >=12min;
Preferably, vacuum processing time is 13~19min;
The processing time of vacuum degree≤3mbar >=10min;
Preferably, the processing time of vacuum degree≤3mbar is 10~14min;
After the processing of vacuum degree≤3mbar, nitrogenous core-spun yarn is fed in ladle, control N content in molten steel be 0.0080%~ 0.0120%.
10. preparation method as claimed in claim 3, it is characterized in that:The continuous casting step meets at least one of following:
Tundish temperature is 1496~1536 DEG C;
Preferably, tundish temperature is 1508~1515 DEG C;
Slab cooling is to room temperature.
CN201810447871.6A 2018-05-11 2018-05-11 Containing V, N Micro Alloying pre-hardened plastic mold steel and preparation method thereof Pending CN108504935A (en)

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Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN109266966A (en) * 2018-11-02 2019-01-25 江苏永钢集团有限公司 One kind is directly cut with Micro Alloying round steel and its production method
CN109852873A (en) * 2019-04-09 2019-06-07 攀钢集团攀枝花钢铁研究院有限公司 The composite brake beam steel of railway freight-car containing V and its manufacturing method with corrosion resisting property
CN109913760A (en) * 2019-04-09 2019-06-21 攀钢集团攀枝花钢铁研究院有限公司 Railway freight-car composite brake beam steel and its manufacturing method containing V
CN109913761A (en) * 2019-04-09 2019-06-21 攀钢集团攀枝花钢铁研究院有限公司 Railway freight-car composite brake beam steel and its manufacturing method containing V, Ni

Citations (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2006002237A (en) * 2004-06-21 2006-01-05 Kobe Steel Ltd Steel for plastic mold excellent in texturability and machinability
CN101476086A (en) * 2008-01-02 2009-07-08 宝山钢铁股份有限公司 Economic steel for plastic cavity die and manufacturing method thereof
CN101542007A (en) * 2006-09-01 2009-09-23 格奥尔格斯玛林许特有限公司 Steel, and processing method for the production of higher-strength fracture-splittable machine components
CN101760701A (en) * 2009-12-25 2010-06-30 舞阳钢铁有限责任公司 Alloy-plastic steel plate for die and production method thereof
JP2010174319A (en) * 2009-01-29 2010-08-12 Daido Steel Co Ltd Steel for plastic molding mold, and plastic molding mold
CN102286698A (en) * 2010-06-17 2011-12-21 宝山钢铁股份有限公司 Plastic mold steel and manufacture method thereof
CN102605261A (en) * 2012-03-23 2012-07-25 宝山钢铁股份有限公司 Hot stamping mould steel and method for manufacturing same
CN102899571A (en) * 2011-07-25 2013-01-30 宝山钢铁股份有限公司 Pre-hardening type plastic mold steel and manufacturing method thereof
CN103757544A (en) * 2013-12-05 2014-04-30 南京钢铁股份有限公司 Economical non-quenched and non-tempered micro-alloyed plastic die steel plate and making method thereof
CN105063512A (en) * 2015-08-26 2015-11-18 山西太钢不锈钢股份有限公司 Plastic die steel and manufacturing method thereof
CN105112794A (en) * 2015-08-25 2015-12-02 石家庄钢铁有限责任公司 Low-cost plastic mold steel and production method thereof
CN106521336A (en) * 2016-11-09 2017-03-22 江苏沙钢集团淮钢特钢股份有限公司 Steering knuckle non-quenched and tempered steel substituting 40Cr quenched and tempered steel and production method thereof
CN107287504A (en) * 2017-06-16 2017-10-24 上海大学 The middle carbon easy-cutting non-hardened and tempered steel and its manufacturing technique method of sulfur-bearing, tellurium
CN107587073A (en) * 2017-09-19 2018-01-16 北京科技大学 A kind of titaniferous, the automobile engine crankshaft non-hardened and tempered steel of nitrogen and preparation method
CN107619995A (en) * 2017-08-11 2018-01-23 江阴兴澄特种钢铁有限公司 A kind of major diameter engineering mechanical hydraulic oil cylinder piston rod round steel and its manufacture method

Patent Citations (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2006002237A (en) * 2004-06-21 2006-01-05 Kobe Steel Ltd Steel for plastic mold excellent in texturability and machinability
CN101542007A (en) * 2006-09-01 2009-09-23 格奥尔格斯玛林许特有限公司 Steel, and processing method for the production of higher-strength fracture-splittable machine components
CN101476086A (en) * 2008-01-02 2009-07-08 宝山钢铁股份有限公司 Economic steel for plastic cavity die and manufacturing method thereof
JP2010174319A (en) * 2009-01-29 2010-08-12 Daido Steel Co Ltd Steel for plastic molding mold, and plastic molding mold
CN101760701A (en) * 2009-12-25 2010-06-30 舞阳钢铁有限责任公司 Alloy-plastic steel plate for die and production method thereof
CN102286698A (en) * 2010-06-17 2011-12-21 宝山钢铁股份有限公司 Plastic mold steel and manufacture method thereof
CN102899571A (en) * 2011-07-25 2013-01-30 宝山钢铁股份有限公司 Pre-hardening type plastic mold steel and manufacturing method thereof
CN102605261A (en) * 2012-03-23 2012-07-25 宝山钢铁股份有限公司 Hot stamping mould steel and method for manufacturing same
CN103757544A (en) * 2013-12-05 2014-04-30 南京钢铁股份有限公司 Economical non-quenched and non-tempered micro-alloyed plastic die steel plate and making method thereof
CN105112794A (en) * 2015-08-25 2015-12-02 石家庄钢铁有限责任公司 Low-cost plastic mold steel and production method thereof
CN105063512A (en) * 2015-08-26 2015-11-18 山西太钢不锈钢股份有限公司 Plastic die steel and manufacturing method thereof
CN106521336A (en) * 2016-11-09 2017-03-22 江苏沙钢集团淮钢特钢股份有限公司 Steering knuckle non-quenched and tempered steel substituting 40Cr quenched and tempered steel and production method thereof
CN107287504A (en) * 2017-06-16 2017-10-24 上海大学 The middle carbon easy-cutting non-hardened and tempered steel and its manufacturing technique method of sulfur-bearing, tellurium
CN107619995A (en) * 2017-08-11 2018-01-23 江阴兴澄特种钢铁有限公司 A kind of major diameter engineering mechanical hydraulic oil cylinder piston rod round steel and its manufacture method
CN107587073A (en) * 2017-09-19 2018-01-16 北京科技大学 A kind of titaniferous, the automobile engine crankshaft non-hardened and tempered steel of nitrogen and preparation method

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN109266966A (en) * 2018-11-02 2019-01-25 江苏永钢集团有限公司 One kind is directly cut with Micro Alloying round steel and its production method
CN109266966B (en) * 2018-11-02 2020-09-25 江苏永钢集团有限公司 Non-quenched and tempered round steel for direct cutting and production method thereof
CN109852873A (en) * 2019-04-09 2019-06-07 攀钢集团攀枝花钢铁研究院有限公司 The composite brake beam steel of railway freight-car containing V and its manufacturing method with corrosion resisting property
CN109913760A (en) * 2019-04-09 2019-06-21 攀钢集团攀枝花钢铁研究院有限公司 Railway freight-car composite brake beam steel and its manufacturing method containing V
CN109913761A (en) * 2019-04-09 2019-06-21 攀钢集团攀枝花钢铁研究院有限公司 Railway freight-car composite brake beam steel and its manufacturing method containing V, Ni
CN109913760B (en) * 2019-04-09 2020-10-16 攀钢集团攀枝花钢铁研究院有限公司 V-containing steel for railway wagon combined brake beam and manufacturing method thereof

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Application publication date: 20180907