CN107988565A - A kind of high toughness high hardenability high speed axle steel and its heat treatment method - Google Patents
A kind of high toughness high hardenability high speed axle steel and its heat treatment method Download PDFInfo
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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
- C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
- C22C38/40—Ferrous alloys, e.g. steel alloys containing chromium with nickel
- C22C38/54—Ferrous alloys, e.g. steel alloys containing chromium with nickel with boron
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- 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
- C21D1/18—Hardening; Quenching with or without subsequent tempering
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- 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
- C21D8/005—Modifying the physical properties by deformation combined with, or followed by, heat treatment of ferrous alloys
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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
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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
- C22C38/04—Ferrous alloys, e.g. steel alloys containing manganese
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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
- C22C38/06—Ferrous alloys, e.g. steel alloys containing aluminium
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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
- C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
- C22C38/40—Ferrous alloys, e.g. steel alloys containing chromium with nickel
- C22C38/44—Ferrous alloys, e.g. steel alloys containing chromium with nickel with molybdenum or tungsten
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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
- C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
- C22C38/40—Ferrous alloys, e.g. steel alloys containing chromium with nickel
- C22C38/46—Ferrous alloys, e.g. steel alloys containing chromium with nickel with vanadium
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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
- C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
- C22C38/40—Ferrous alloys, e.g. steel alloys containing chromium with nickel
- C22C38/48—Ferrous alloys, e.g. steel alloys containing chromium with nickel with niobium or tantalum
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- 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
- C21D2211/00—Microstructure comprising significant phases
- C21D2211/001—Austenite
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- 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
- C21D2211/00—Microstructure comprising significant phases
- C21D2211/008—Martensite
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Abstract
A kind of high toughness high hardenability high speed axle steel, the yield strength R of the axle steelp0.2>=630MPa, tensile strength Rm >=800MPa, the impact of collision of elongation percentage A >=20%, 5mm notch room temperature absorb work(KU2>=80J, ductile-brittle transition temperature are less than 40 DEG C；The chemical composition of the steel includes B, and the B is 0.0008~0.0025% by weight percentage.The present invention also provides the preparation method of the steel at the same time.The present invention gives full play to effect of each element in axle steel, obtains that crystal grain is tiny and microscopic structure based on martensite.The martensitic structure of uniform fine grain austenite grain and Nb microalloys nano-second-phase enhancing can be obtained using the heat treatment of quenching+high tempering twice, realize the excellent matching of high intensity, high tenacity and high-hardenability, finally make high speed axle that there is the military service performance such as good shock resistance, antifatigue, the matching of excellent obdurability and good quenching degree.
Description
Technical field
The present invention relates to railcar axle-steel technical field, more particularly to a kind of fine grain, high-strength tenacity and high-hardenability
High speed axle steel and its heat treatment method.
Background technology
Axle is one of most harsh component of rail transit train service condition, bears the dead weight of train almost all and bears
Lotus.With putting into operation for China express railway, train speed further improves so that axle dynamic loading is continuously increased, to car
The safety and reliability of axis brings very big challenge, and the requirement of higher is proposed to the performance of axle material.Due to various countries
National conditions are different with technical thought, and the axle material of each railway developed country high-speed railway in the world is broadly divided into two major classes：In high-quality
Carbon steel and high strength alloy steel.As modern architecture in Japan high-speed railway axle generally uses carbon steel (S38C), using
Surface mid frequency induction hardening heat treatment process, complex process are high to the technology controlling and process level requirement of equipment and personnel；European high-speed railway
Axle material then uses low-alloy structural steel (such as EA4T) mostly, 0.90-1.20wt.% containing Cr, Mo 0.15-0.30wt.%,
Respective organization and performance can be obtained by traditional Tempering and Quenching mode, but since this steel alloy content is relatively low, it is big to cut
Face axle there are quenching degree it is insufficient the problem of, axle section structure and performance are uneven, influence its overall performance；European high ferro car
Shaft material small part selects 30NiCrMoV12 medium alloy constructional steels, in steel containing 0.60~1.00wt.% of Cr, Ni 2.70~
0.40~0.60wt.% of 3.30wt.%, Mo, V0.08~0.13wt.%, such steel grade quenching degree is good, can oil quenching, hardness it is high,
Corrosion resistance and good, but cost is higher.Horizontal and axle manufacturing enterprise actual heat treatment is smelted according to the current steel billet in China
Technological equipment situation, the preferential technology road for having selected alloying Tempering and Quenching of development of production domesticization high-speed EMU axle
Line.Chinese patent 201410532111.7 provides a kind of axle steel, on the basis of EA4T steel chemical compositions, by adding Nb
0.015~0.060wt.%, B0.0008~0.0050wt.%, to improve the quenching degree of steel, but due to not adopting an effective measure
To fix the N in steel, part B can be combined generation BN with N more than needed so that and it improves the effect of quenching degree and falls flat,
Meanwhile to separate out size larger by BN, also easily leads to that the crystallite dimension of steel is uneven, reduces the performance of axle.
The content of the invention
In view of analyze above, the present invention is intended to provide the boron containing niobium of a kind of fine grain, high tenacity and high-hardenability arranges at a high speed
Car axles steel.In chemical composition, low C, the Alloying Design based on Cr, Ni in using, are cooperateed with using high Nb, micro- V, Mo
Multi-element composite micro-alloying thinking, it is preferred that emphasis is the Proper Match of C, Nb, V, Mo, Cr element, gives full play to it in axle steel
In effect, obtain that crystal grain is tiny and microscopic structure based on martensite, ensure the through hardening of axle steel furthermore with the B of solid solution
Property not because crystal grain refinement and NbC are separated out and are reduced, make axle steel that there is high intensity, high tenacity, high-hardenability etc. to integrate mechanical property
Can, so as to possess good shock resistance and the military service performance such as antifatigue.
The purpose of the present invention is mainly achieved through the following technical solutions：
A kind of high toughness high hardenability high speed axle steel, the yield strength R of the axle steelp0.2>=630MPa, tension
Intensity Rm >=800MPa, the impact of collision of elongation percentage A >=20%, 5mm notch room temperature absorb work(KU2>=80J, ductile-brittle transition temperature are low
In -40 DEG C；The chemical composition of the steel includes B, and B is 0.0008~0.0025% by weight percentage.
Further, the chemical composition of the steel is C by weight percentage：0.24~0.32%, Si：0.20~
0.40%, Cr：0.90~1.20%, Mn：0.60~0.90%, V：0.00~0.06%, Nb：0.08~0.12%, Ni：
0.50~1.50%, Mo：0.20~0.30%, Alt：0.020~0.040%, P：<0.010%, S：<0.010%, O：<
0.0015%, N：<0.008%, remaining is Fe and inevitable impurity.
Further, the average grain size of austenite grain is less than 12 μm in the tissue of the axle steel.
The present invention also provides a kind of preparation method of the high toughness high hardenability high speed axle steel, using converter, electricity
Stove or vacuum induction furnace smelting, continuous casting or molding after external refining, strand is air-cooled after forging rolling through the laggard driving axis forging rolling of cogging,
It is heat-treated, obtains high toughness high hardenability high speed axle steel.
Further, the heating-up temperature of forging rolling is 1150~1250 DEG C, and finish-forging and finishing temperature are not less than 850 DEG C
Austenite decomposes phase transformation, finish-forging and finishing temperature not less than 850 DEG C during to avoid forging rolling, air-cooled after forging rolling,
Tiny austenite grain and the matching of excellent obdurability can be obtained using the heat treatment of quenching+high tempering twice.
Further, after the heat treatment is specifically, the steel after forging rolling carries out quenching heat treatment twice in hardening media,
Temper is carried out again, obtains the axle steel.
Further, the temperature for carrying out first time quenching heat treatment is 900~950 DEG C, the heating and thermal insulation time for 10~
60min。
Further, the temperature for carrying out second of quenching heat treatment is 850~900 DEG C, the heating and thermal insulation time for 30~
120min。
900~950 DEG C of progress austenitizings of first time hardening heat selection higher temperature, it is therefore an objective to eliminate forging or rolling
Heterogeneous structure, while make the part back dissolving such as V, Nb and homogenization, the insulation of 10~60min of short period is to suppress difficult to understand
Family name's body crystal grain and MX particles (M is separated out：V, Nb, X：C, N) particle roughening, quick cooling is martensite/bayesian in order to obtain
Body tissue, while suppress MX and separated out in cooling high temperature section.
In first time, quenching is obtained on more uniform tiny martensite organization foundation, and second of hardening heat selection is compared with low temperature
850-900 DEG C of degree carries out secondary austenitizing, mainly obtains more nanometer MX particles, and reduce AUSTENITE GRAIN COARSENING and incline
To thus soaking time can also extend to 120min, final to obtain uniformly tiny austenite grain and its phase-change organization.
Further, the temperature of temper is 620~680 DEG C, air-cooled after tempering to arrive room when soaking time 3~8 is small
Temperature.
Further, it is characterised in that the hardening media is water, water mist or oil.
The effect of each element of the present invention and proportioning are according to as follows：
Carbon：One of most important intensified element and element of raising quenching degree, to ensure enough intensity and quenching degree, C
Content must be in more than 0.24wt.%；But when C content is higher than 0.32wt.%, the plasticity and toughness of steel can be significantly reduced, therefore
It is 0.24~0.32wt.% that the present invention, which controls C content,.
Silicon：Solution strengthening effect is notable but damages toughness also significant alloying element, while is also deoxidation main in steel
Element.Therefore, the present invention mainly utilizes its deoxidation, and it is reduced levels to control Si contents, is 0.20~0.40wt.%.
Manganese：The effective element of deoxidization desulfuration, while be also the element for ensureing quenching degree.But similar with Si, Mn contents exceed
The toughness of steel can be significantly reduced during 0.90wt.%, Mn contents are too low then effectively deoxidization desulfuration and cannot to ensure the quenching degree of steel.Cause
This, it is 0.60~0.90% that the present invention, which controls Mn contents,.
Chromium：Moderate Cr is added in steel of the present invention can not only significantly improve the quenching degree of steel, moreover it is possible to improve material structure
Uniformity.(Fe, Cr) is formed when Cr is dissolved in cementite3During C alloy cementite, the work of crystal grain thinning and cementite can be played
With so as to obtain uniformly tiny quenching crystal grain and tempered structure, being improved the obdurability of material.But excessive Cr and C
Easily form Cr7C3Deng carbide, toughness, the plasticity of steel are damaged.Therefore, the present invention control Cr contents be 0.90~
1.20wt.%.
Nickel：Improve the most effective alloying element of steel toughness, cda alloy cost and its with other alloying elements tough
Property, the collaboration in terms of quenching degree, the content of Ni is controlled in 0.50~1.50wt.% in steel of the present invention.
Molybdenum：The present invention obtains tiny austenite grain, significant nano-second-phase by Mo, Nb, V combined microalloying
Precipitation strengthening effect and high resistance to tempering, it is hereby achieved that fine grain, high tenacity high tempering tissue.In addition, Mo with
The rational proportion of the alloying elements such as Cr, Ni and C, V, can obtain good quenching degree under fine austenite crystalline form.Mo
Content be less than 0.20, above-mentioned effect is limited, too high levels, then above-mentioned effect saturation even result in improve resistance to tempering make it is used
It is surplus, the alloy and tempering heat treatment process cost of steel will be improved.Therefore, 0.20~0.30wt.% of present invention control Mo contents.
Niobium：Steel of the present invention is middle low-carbon alloy steel, the higher Nb microalloyings of use, first in solidification can fully with
N, which is combined, separates out carbonitride, reduces B and N and combines to form BN, to ensure the effect of the raising quenching degree of B；Secondly, before forging rolling
When soaking and heat treatment, Nb (C, N) fining austenite grains are separated out；Again, heat treatment reheats considerable part in austenite and consolidates
Molten Nb-B easily in crystal boundary segregation, postpones austenite phase transformation, improves the quenching degree of steel.Too low more than Nb comprehensive functions are unknown
It is aobvious.Therefore, steel Nb contents control of the present invention is in 0.08~0.12wt.%.
Add and the strong nitride forming element such as Al, Ti or Nb is additionally added in B steel alloys to fix N, avoid the precipitation of BN, but
When Al content is excessive, Al is combined to form with O2O3Field trash, its size is generally large and is difficult control, easily as fatigue crack
Source, significantly reduces the fatigue behaviour of axle；TiN is higher due to Precipitation Temperature, it is easy to grow up to bigger size (micron order),
And there are sharp corners in form, the toughness and fatigue behaviour to steel are very unfavorable；Nb is usually separated out thin in crystal boundary in steel alloy
Small carbonitride, with pinning crystal boundary, fining austenite grains size, can improve the intensity and toughness of steel.Therefore, height is passed through
The combined microalloying of Nb, B collaboration, can be effectively improved its quenching degree while axle steel obdurability is ensured.
Boron：Segregation improves grain-boundary strength to crystal boundary, improves quenching degree.Acted on not more than when B content is less than 0.0008wt.%
Effect increase unobvious when substantially, higher than 0.0025wt.%.B content control in steel of the present invention 0.0008~
0.0025wt.%.
Vanadium：Steel of the present invention is middle low-carbon alloy steel, using micro V microalloyings, separated out in forging rolling (V, Mo) (C,
N), precipitation enhancement is produced, while the V being partly dissolved in austenite can improve quenching degree.Steel V content control of the present invention exists
0.00~0.06wt.%, excessive V content can cause that VC Precipitation Temperatures are excessive, amount of precipitation is excessive, particle size is easily thick,
It is unfavorable for fining austenite grains, intensity, toughness to axle steel etc. are unfavorable.
Aluminium：Al is strong deoxidant element, can also combine to form AlN with N, can play Grain refinement, content is less than
0.020wt.%, above effect unobvious.Al content in steel of the present invention is controlled in 0.020~0.040wt.%.
Nitrogen：In the presence of having Nb, V, Al etc. in steel, N can form carbonitride with them, can effectively suppress austenite
Crystal grain is grown up.Steel of the present invention Nb, V, Al equal size design allow N content control range be<0.005wt.%.
Oxygen：O easily forms oxide and is mingled with, and is the impurity element of high speed axle steel, unfavorable to toughness, plasticity, serious to reduce
Fatigue behaviour.Steel control O content of the present invention is less than 0.0015%.
Phosphorus：Steel of the present invention is controlled P as impurity element, content<0.010wt.%.
Sulphur：Steel of the present invention is controlled S as impurity element, content<0.010wt.%.
The present invention has the beneficial effect that：
The present invention provides a kind of the present application a kind of new Cr-Ni-Mo-Nb-B-V high speed axles steels, uses
Low C, high Nb, B, Mo, micro- V combined microalloyings, the design of higher Cr, Ni alloy in new, it is preferred that emphasis is C, Nb, V, Mo, Cr member
The Proper Match of element：The content of V is controlled to produce precipitation enhancement, while improves quenching degree；The Nb of high level can in steel
So that almost all of N is shared by Nb (C, N), ensure that B still in solid solution state, significantly postpones austenite phase transformation, so that bright
The aobvious quenching degree for improving steel；Moderate Cr, crystal grain thinning and cementite are added, significantly improves the quenching degree of steel, improves material group
The uniformity knitted, is improved the obdurability of material；Ensure the quenching degree of axle steel not because crystal grain is thin furthermore with the B of solid solution
Change and NbC is separated out and reduced；Using higher Nb microalloyings, improve the effect of quenching degree, fining austenite grains and improve
The quenching degree of steel；Cda alloy cost and its synergistic effect selection with other alloying elements in terms of obdurability, quenching degree are closed
Suitable Ni contents；The present invention gives full play to its effect in axle steel, and it is tiny and micro- based on martensite to obtain crystal grain
Tissue.
The present invention can obtain the micro- conjunction of uniform fine grain austenite grain and Nb using the heat treatment of quenching+high tempering twice
The martensitic structure of the second phase of gold nano enhancing, realizes the excellent matching of high intensity, high tenacity and high-hardenability, finally makes at a high speed
Axle has the military service performance such as good shock resistance, antifatigue, the matching of excellent obdurability and good quenching degree.
The average grain size of austenite grain is less than 12 μm in the tissue of axle steel of the present invention, yield strength Rp0.2
>=630MPa, tensile strength Rm >=800MPa, the impact of collision of elongation percentage A >=20%, 5mm notch room temperature absorb work(KU2>=80J,
Ductile-brittle transition temperature is less than -40 DEG C.
Other features and advantages of the present invention will illustrate in the following description, also, part can become from specification
Obtain it is clear that or being understood by implementing the present invention.The purpose of the present invention and other advantages can be by the explanations write
Specifically noted method is realized and obtained in book, claims and embodiment.
Embodiment
With reference to embodiment, the invention will be further described, and the embodiment of the present invention can be used for the original of the explaination present invention
Reason.
The present invention relates to a kind of high toughness high hardenability high speed axle steel, the chemical composition of the steel include C, Si, Cr,
Mn, V, Nb, B, Ni, Mo, Alt, P, S, O and N, and Fe and inevitable impurity.
Preferably, C content is 0.24~0.32wt.%, and carbon is most important intensified element and the element for improving quenching degree
One of, to ensure enough intensity and quenching degree, C content must be in more than 0.24wt.%；But C content is higher than 0.32wt.%
When, the plasticity and toughness of steel can be significantly reduced.
Preferably, it is reduced levels to control Si contents, is 0.20~0.40wt.%, silicon be solution strengthening effect significantly but
Toughness also significant alloying element is damaged, while is also deoxidant element main in steel.The present invention mainly utilizes its deoxidation.
Preferably, Mn contents are 0.60~0.90%, and manganese is the effective element of deoxidization desulfuration, while are also to ensure quenching degree
Element.But it is similar with Si, the toughness of steel can be significantly reduced when Mn contents are more than 0.90wt.%, Mn contents are too low, cannot have
Imitate deoxidization desulfuration and ensure the quenching degree of steel.
Preferably, Cr contents are 0.90~1.20wt.%, and adding moderate Cr in steel of the present invention can not only significantly improve
The quenching degree of steel, moreover it is possible to improve the uniformity of material structure.(Fe, Cr) is formed when Cr is dissolved in cementite3During C alloy cementite,
It can play the role of crystal grain thinning and cementite, so as to obtain uniformly tiny quenching crystal grain and tempered structure, make the strong of material
Toughness is improved.But excessive Cr and C easily forms Cr7C3Deng carbide, toughness, the plasticity of steel are damaged.
Preferably, the content control of Ni is in 0.50~1.50wt.%, its purpose is to improve steel toughness, and meanwhile it is comprehensive
Close cost of alloy and its cooperateing with terms of obdurability, quenching degree with other alloying elements.
Preferably, present invention control Mo 0.20~0.30wt.% of content, the present invention pass through Mo, Nb, V combined microalloying
Tiny austenite grain, significant nano-second-phase precipitation strengthening effect and high resistance to tempering are obtained, it is hereby achieved that
Fine grain, high tenacity high tempering tissue.In addition, the rational proportion of the alloying element such as Mo and Cr, Ni and C, V, in tiny Austria
Good quenching degree can be obtained under family name's body crystalline form.Mo contents be less than 0.20, above-mentioned effect is limited, too high levels, then on
State effect saturation and even result in the effect surplus for improving resistance to tempering, the alloy and tempering heat treatment process cost of steel will be improved.
Preferably, the control of Nb contents is middle low-carbon alloy steel in 0.08~0.12wt.%, steel of the present invention, and use is higher
Nb microalloyings, can fully be combined with N in solidification separate out carbonitride first, reduced B and N and combine to form BN, to ensure B
Raising quenching degree effect；Secondly, Nb (C, N) fining austenite grains are separated out when soaking and heat treatment before forging rolling；Again
Secondary, heat treatment reheats the Nb-B of considerable part solid solution in austenite easily in crystal boundary segregation, postpones austenite phase transformation, improves steel
Quenching degree, too low more than Nb comprehensive function unobvious.The combined microalloying that the present invention is cooperateed with by high Nb, B, can protect
Its quenching degree is effectively improved while demonstrate,proving axle steel obdurability.
Preferably, the B content control in steel of the present invention improves crystal boundary in 0.0008~0.0025wt.%, segregation to crystal boundary
Intensity, improves quenching degree.Acted on when acting on unobvious more than when B content is less than 0.0008wt.%, and being higher than 0.0025wt.%
Increase unobvious.
Preferably, in 0.00~0.06wt.%, steel of the present invention is middle low-carbon alloy steel, is used for steel V content control of the present invention
Micro V microalloyings, (V, Mo) (C, N) is separated out in forging rolling, produces precipitation enhancement, while be partly dissolved in austenite
V can improve quenching degree.Excessive V content can cause that VC Precipitation Temperatures are excessive, amount of precipitation is excessive, particle size is easily thick
Greatly, it is unfavorable for fining austenite grains, intensity, toughness to axle steel etc. are unfavorable.
Preferably, the Al content in steel of the present invention is controlled in 0.020~0.040wt.%, and Al is strong deoxidant element, may be used also
AlN is combined to form with N, Grain refinement can be played, content is less than 0.020wt.%, above effect unobvious.
Preferably, in the presence of having Nb, V, Al etc. in steel, N can form carbonitride with them, can effectively suppress difficult to understand
Family name's body crystal grain is grown up.Steel of the present invention Nb, V, Al equal size design allow N content control range be<0.005wt.%.
Preferably, impurity content is P in the present invention：<0.010%, S：<0.010%, O：<0.0015%.
High tenacity high speed axles steel according to the present invention uses converter, electric furnace or vacuum induction furnace smelting, the outer essence of stove
Continuous casting or molding after refining, for strand through the laggard driving axis forging rolling of cogging, heating-up temperature is 1150~1250 DEG C, difficult to understand during to avoid forging rolling
Family name's body decomposes phase transformation, finish-forging and finishing temperature not less than 850 DEG C, air-cooled after forging rolling, using the heat of quenching+high tempering twice
Processing can obtain tiny austenite grain and the matching of excellent obdurability.Steel of the present invention by vacuum induction furnace smelting, its
Middle 1#~5# is embodiment steel, and compared steel is the experiment steel designed according to EA4T standards.
Five specific embodiments are given below, wherein 1#~5# is embodiment steel, and compared steel is to be designed according to EA4T standards
Experiment steel, chemical composition is as shown in table 1.Steel of the present invention by vacuum induction furnace smelting, embodiment steel with compared steel through smelting,
Casting, after forging rolling, be processed into normal room temperature tensile sample (L0=5d0, d0=5mm), Charpy notch impact specimen (10mm ×
10mm × 55mm), metallographic specimen (10mm × 10mm × 20mm), steel end-quenched (Φ 25mm × 110mm).Tensile sample, impact
Sample and metallographic specimen are heated to 920 DEG C in a vacuum furnace, keep the temperature 1h, then air-cooled, are then heated to 880 in a vacuum furnace again
DEG C, keep the temperature 1h, oil quenching.Temperature during temper is 675 DEG C, and soaking time 4h, room temperature is air-cooled to after tempering.Stretching examination
Sample and impact specimen are processed into final size, and are accordingly tested according to national standard, its mechanical performance index is listed in table 2,
Metallographic specimen is ground again, polishing, and after saturation picric acid aqueous corrosion, original austenite grain is measured using division lines method
Degree, the results are shown in Table 2.Steel end-quenched, into standard specimen, end quenching examination is carried out by national standard through 920 DEG C of insulation air-cooled post-processings of 0.5h
Test and measure ending quenching hardness, the hardness number away from quenched end different distance is shown in Table 3.Tempered martensite is obtained after heat treatment, it is real
Apply 1#~5# steel obtain more than tensile strength 800MPa, the favorable comprehensive mechanical property of more than room temperature impact work(80J, and
To uniformly tiny austenite grain, average-size is 9-12 μm, and quenching degree is significantly improved, and is had compared with compared steel more excellent
Obdurability matches.The chemical composition of embodiment 1-5 is as shown in table 1, its mechanical performance index is listed in table 2, and metallographic specimen is again
Ground, polishing, and after saturation picric acid aqueous corrosion, original austenite grain degree is measured using division lines method, as a result such as table 2
It is shown.Steel end-quenched, into standard specimen, carries out end quenching test by national standard and measures end quenching through 920 DEG C of insulation air-cooled post-processings of 0.5h
Hardness, the hardness number away from quenched end different distance are shown in Table 3.In table 1-3, Rp0.2For yield strength, Rm is tensile strength, and A is to prolong
Stretch rate, KU2Work(is absorbed for the impact of collision of room temperature 5mm notches.
1 chemical composition of table (wt.%)
Mechanical property when table 2 is tempered
3 quenching degree of table
Tempered martensite is obtained after heat treatment, embodiment 1#~5# steel obtains more than tensile strength 800MPa, room
The favorable comprehensive mechanical property of warm more than ballistic work 80J, and uniformly tiny austenite grain is obtained, average-size is 9-12 μ
M, quenching degree are significantly improved, and are matched compared with compared steel with more excellent obdurability.
It is an object of the invention to provide the bullet train of boron containing the niobium axle use of a kind of fine grain, high tenacity and high-hardenability
Steel.In chemical composition, low C, the Alloying Design based on Cr, Ni in using, are cooperateed with polynary multiple using high Nb, micro- V, Mo
Closing microalloying thinking, it is preferred that emphasis is the Proper Match of C, Nb, V, Mo, Cr element, gives full play to its effect in axle steel,
Obtain that crystal grain is tiny and microscopic structure based on martensite, ensure the quenching degree of axle steel not because of crystalline substance furthermore with the B of solid solution
Grain refinement and NbC are separated out and reduced, and axle steel is had the comprehensive mechanical properties such as high intensity, high tenacity, high-hardenability, so as to have
Standby good shock resistance and the military service performance such as antifatigue.
The foregoing is only a preferred embodiment of the present invention, but protection scope of the present invention be not limited thereto,
Any one skilled in the art the invention discloses technical scope in, the change or replacement that can readily occur in,
It should be covered by the protection scope of the present invention.
Claims (10)
- A kind of 1. high toughness high hardenability high speed axle steel, it is characterised in that the yield strength R of the axle steelp0.2≥ 630MPa, tensile strength Rm >=800MPa, the impact of collision of elongation percentage A >=20%, 5mm notch room temperature absorb work(KU2>=80J, it is tough Crisp transition temperature is less than -40 DEG C；The chemical composition of the steel includes B, wherein B by weight percentage for 0.0008~ 0.0025%.
- 2. high toughness high hardenability high speed axle steel according to claim 1, it is characterised in that the chemical composition of the steel It is C by weight percentage：0.24~0.32%, Si：0.20~0.40%, Cr：0.90~1.20%, Mn：0.60~ 0.90%, V：0.00~0.06%, Nb：0.08~0.12%, Ni：0.50~1.50%, Mo：0.20~0.30%, Alt： 0.020~0.040%, P：<0.010%, S：<0.010%, O：<0.0015%, N：<0.008%, remaining is Fe and can not keep away The impurity exempted from.
- 3. high toughness high hardenability high speed axle steel according to claim 1, it is characterised in that the tissue of the axle steel The average grain size of middle austenite grain is less than 12 μm.
- 4. a kind of preparation method using high toughness high hardenability high speed axle steel any one of claim 1-3, its It is characterized in that, using converter, electric furnace or vacuum induction furnace smelting, continuous casting or molding after external refining, strand carries out after cogging Axle forging rolling, it is air-cooled after forging rolling, it is heat-treated, obtains high toughness high hardenability high speed axle steel.
- 5. the preparation method of high toughness high hardenability high speed axle steel according to claim 4, it is characterised in that forging rolling Heating-up temperature is 1150~1250 DEG C, and finish-forging and finishing temperature are not less than 850 DEG C.
- 6. the preparation method of high toughness high hardenability high speed axle steel according to claim 4, it is characterised in that the heat After processing is specifically, the steel after forging rolling carries out quenching heat treatment twice in hardening media, then temper is carried out, described in acquisition Axle steel.
- 7. the preparation method of high toughness high hardenability high speed axle steel according to claim 4, it is characterised in that carry out the The temperature of primary quenching heat treatment is 900~950 DEG C, and the heating and thermal insulation time is 10~60min.
- 8. the preparation method of high toughness high hardenability high speed axle steel according to claim 4, it is characterised in that carry out the The temperature of secondary quenching heat treatment is 850~900 DEG C, and the heating and thermal insulation time is 30~120min.
- 9. the preparation method of high toughness high hardenability high speed axle steel according to claim 4, it is characterised in that at tempering The temperature of reason is 620~680 DEG C, air-cooled after tempering to arrive room temperature when soaking time 3~8 is small.
- 10. according to the preparation method of high toughness high hardenability high speed axle steel any one of claim 6-9, its feature It is, the hardening media is water, water mist or oil.
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Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109023107A (en) * | 2018-09-21 | 2018-12-18 | 首钢集团有限公司 | A kind of super harden ability axle steel |
| CN109023102A (en) * | 2018-09-21 | 2018-12-18 | 首钢集团有限公司 | A kind of super harden ability axle steel of microalloying |
| CN110079732A (en) * | 2019-05-15 | 2019-08-02 | 燕山大学 | Super harden ability steel and preparation method thereof |
| CN110592312A (en) * | 2019-10-23 | 2019-12-20 | 山西太钢不锈钢股份有限公司 | Preparation method of steel for high-speed axle |
| CN111705195A (en) * | 2020-06-08 | 2020-09-25 | 东莞材料基因高等理工研究院 | Precipitation strengthening heat treatment process for Nb-containing austenitic heat-resistant steel |
| CN113088825A (en) * | 2021-04-14 | 2021-07-09 | 江苏永钢集团有限公司 | Medium carbon microalloyed steel and method for eliminating mixed crystal structure thereof |
| CN114058964A (en) * | 2021-11-30 | 2022-02-18 | 宝武集团马钢轨交材料科技有限公司 | Steel for high-speed axle and heat treatment method and production method thereof |
| CN115558870A (en) * | 2022-11-04 | 2023-01-03 | 马鞍山钢铁股份有限公司 | Economical long-life steel for high-power wind power yaw bearing ring, bearing ring and production process |
| CN116024498A (en) * | 2022-12-26 | 2023-04-28 | 河南中原特钢装备制造有限公司 | Fine-grain high-strength-toughness mirror plastic die steel and heat treatment method thereof |
Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103060715A (en) * | 2013-01-22 | 2013-04-24 | 宝山钢铁股份有限公司 | Ultrahigh tough steel plate with low yield ratio and preparation method thereof |
| CN103898420A (en) * | 2012-12-25 | 2014-07-02 | 隆英(金坛)特钢科技有限公司 | Wear-resisting steel plate and manufacturing method thereof |
| CN104532149A (en) * | 2014-12-22 | 2015-04-22 | 江阴兴澄特种钢铁有限公司 | Round steel with high strength and toughness and hydrogen sulfide stress corrosion resistance for drilling tool and manufacturing method of round steel |
| CN105256242A (en) * | 2015-10-21 | 2016-01-20 | 苏州雷格姆海洋石油设备科技有限公司 | Manufacturing method for forge piece blanks for marine oil exploitation equipment |
| CN105821307A (en) * | 2016-06-07 | 2016-08-03 | 马鞍山钢铁股份有限公司 | Niobium-containing steel for motor train unit axle and production method and heat processing technology thereof |
| CN106498277A (en) * | 2016-09-20 | 2017-03-15 | 舞阳钢铁有限责任公司 | A kind of special thickness high-strength and high-ductility engineering machinery modulation steel plate and production method |
| CN106521356A (en) * | 2016-11-10 | 2017-03-22 | 钢铁研究总院 | High-strength high-toughness corrosion-resistant chain steel and heat treatment method thereof |
-
2017
- 2017-11-28 CN CN201711213726.3A patent/CN107988565B/en active Active
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103898420A (en) * | 2012-12-25 | 2014-07-02 | 隆英(金坛)特钢科技有限公司 | Wear-resisting steel plate and manufacturing method thereof |
| CN103060715A (en) * | 2013-01-22 | 2013-04-24 | 宝山钢铁股份有限公司 | Ultrahigh tough steel plate with low yield ratio and preparation method thereof |
| CN104532149A (en) * | 2014-12-22 | 2015-04-22 | 江阴兴澄特种钢铁有限公司 | Round steel with high strength and toughness and hydrogen sulfide stress corrosion resistance for drilling tool and manufacturing method of round steel |
| CN105256242A (en) * | 2015-10-21 | 2016-01-20 | 苏州雷格姆海洋石油设备科技有限公司 | Manufacturing method for forge piece blanks for marine oil exploitation equipment |
| CN105821307A (en) * | 2016-06-07 | 2016-08-03 | 马鞍山钢铁股份有限公司 | Niobium-containing steel for motor train unit axle and production method and heat processing technology thereof |
| CN106498277A (en) * | 2016-09-20 | 2017-03-15 | 舞阳钢铁有限责任公司 | A kind of special thickness high-strength and high-ductility engineering machinery modulation steel plate and production method |
| CN106521356A (en) * | 2016-11-10 | 2017-03-22 | 钢铁研究总院 | High-strength high-toughness corrosion-resistant chain steel and heat treatment method thereof |
Non-Patent Citations (1)
| Title |
|---|
| 刘吉远、陈雷: "《铁路货车轮轴技术概论》", 31 October 2009, 中国铁道出版社 * |
Cited By (13)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109023102A (en) * | 2018-09-21 | 2018-12-18 | 首钢集团有限公司 | A kind of super harden ability axle steel of microalloying |
| CN109023107A (en) * | 2018-09-21 | 2018-12-18 | 首钢集团有限公司 | A kind of super harden ability axle steel |
| CN110079732A (en) * | 2019-05-15 | 2019-08-02 | 燕山大学 | Super harden ability steel and preparation method thereof |
| CN110079732B (en) * | 2019-05-15 | 2020-08-21 | 燕山大学 | Preparation method of super-hardenability steel |
| CN110592312A (en) * | 2019-10-23 | 2019-12-20 | 山西太钢不锈钢股份有限公司 | Preparation method of steel for high-speed axle |
| CN111705195B (en) * | 2020-06-08 | 2022-09-06 | 东莞材料基因高等理工研究院 | Precipitation strengthening heat treatment process for Nb-containing austenitic heat-resistant steel |
| CN111705195A (en) * | 2020-06-08 | 2020-09-25 | 东莞材料基因高等理工研究院 | Precipitation strengthening heat treatment process for Nb-containing austenitic heat-resistant steel |
| CN113088825A (en) * | 2021-04-14 | 2021-07-09 | 江苏永钢集团有限公司 | Medium carbon microalloyed steel and method for eliminating mixed crystal structure thereof |
| CN113088825B (en) * | 2021-04-14 | 2023-02-28 | 江苏永钢集团有限公司 | Medium carbon microalloyed steel and method for eliminating mixed crystal structure thereof |
| CN114058964A (en) * | 2021-11-30 | 2022-02-18 | 宝武集团马钢轨交材料科技有限公司 | Steel for high-speed axle and heat treatment method and production method thereof |
| CN115558870A (en) * | 2022-11-04 | 2023-01-03 | 马鞍山钢铁股份有限公司 | Economical long-life steel for high-power wind power yaw bearing ring, bearing ring and production process |
| WO2024093461A1 (en) * | 2022-11-04 | 2024-05-10 | 马鞍山钢铁股份有限公司 | Steel for economical, long-service-life and high-power wind power yaw bearing ring, bearing ring and production process therefor |
| CN116024498A (en) * | 2022-12-26 | 2023-04-28 | 河南中原特钢装备制造有限公司 | Fine-grain high-strength-toughness mirror plastic die steel and heat treatment method thereof |
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