CN109022697B - A kind of Micro Alloying mould steel and preparation method thereof - Google Patents
A kind of Micro Alloying mould steel and preparation method thereof Download PDFInfo
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- CN109022697B CN109022697B CN201811105774.5A CN201811105774A CN109022697B CN 109022697 B CN109022697 B CN 109022697B CN 201811105774 A CN201811105774 A CN 201811105774A CN 109022697 B CN109022697 B CN 109022697B
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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
- 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
- C22C33/00—Making ferrous alloys
- C22C33/04—Making ferrous alloys by melting
- C22C33/06—Making ferrous alloys by melting using master 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
- C22C38/001—Ferrous alloys, e.g. steel alloys containing N
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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
- C22C38/002—Ferrous alloys, e.g. steel alloys containing In, Mg, or other elements not provided for in one single group C22C38/001 - C22C38/60
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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
- C22C38/005—Ferrous alloys, e.g. steel alloys containing rare earths, i.e. Sc, Y, Lanthanides
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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
- C22C38/22—Ferrous alloys, e.g. steel alloys containing chromium 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
- C22C38/24—Ferrous alloys, e.g. steel alloys containing chromium 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
- C22C38/26—Ferrous alloys, e.g. steel alloys containing chromium with niobium or tantalum
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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
- C22C38/34—Ferrous alloys, e.g. steel alloys containing chromium with more than 1.5% by weight of 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
- C22C38/18—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
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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
- C22C38/60—Ferrous alloys, e.g. steel alloys containing lead, selenium, tellurium, or antimony, or more than 0.04% by weight of sulfur
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- Heat Treatment Of Steel (AREA)
Abstract
A kind of non-tempering easy cutting die steel has following component: C:0.35-0.55% by percentage to the quality, Si:1.5-2.2%, Mn:1.8-2.4%, Cr:0.5-0.9%, S:0.05-0.15%, Mg:0.001-0.015%, Al:0.01-0.05%, Ca:0.0006-0.0012%, V:0.1-0.3%, Mo:0.1-0.6%, RE:0.05-0.1%；N:0.01-0.08%, Nb:0.1-0.25%, surplus are Fe and inevitable impurity element.
Description
Technical field
The present invention relates to the steel alloy smelting processes of steel industry, refer in particular to non-tempering easy cutting die steel production work
Skill.
Background technique
Automatic steel is that one or more of elements are added in steel, is formed using itself or other elements to machining
Advantageous field trash improves the machinabilities of steel.Automatic steel has preferable machinability and preferable any surface finish
Degree, can reduce the manufacturing cost of product.
Non-hardened and tempered steel is the engineering steel required without modifier treatment performance that can be achieved, using such steel making zero
Part can save Tempering and Quenching process and equipment, meanwhile, the generated waste product in heat treatment process is avoided, dirt is reduced
Dye, low energy consumption, this steel belong to energy-saving steel.
Mould steel is most important for modern industry, requires die steel material mainly to include mechanical property appropriate
Energy, good machinability, preferable polishing, decorative pattern etching, anti-corrosion and welding performance etc..Car industry and white goods system
The responsible consumer that industry is plastic mould consumption is made, in the production link of such mold, relative to die steel module production cost,
Expense needed for product machining is often higher, even up to entire die cost in the manufacture of certain specialities
80%, at the same time, the shortening of product life cycle and the quickening of update speed force the mold production time to compress, good
Good machinability has become an important indicator for determining die steel material quality.
Summary of the invention
The present invention provides a kind of Micro Alloying mould steel with good cutting, passes through answering for Mg, Ca, RE, Al etc.
Addition is closed, further reduced its processing cost and production cost on the basis of meeting original mould steel performance requirement, is reduced
The production energy consumptions of mold materials shortens life cycle of the product, is suitable for large range promotion use.
Specific technical solution is:
A kind of mould steel has following component by percentage to the quality:
C:0.35-0.55%, Si:1.5-2.2%, Mn:1.8-2.4%, Cr:0.5-0.9%, S:0.05-0.15%,
Mg:0.001-0.015%, Al:0.01-0.05%, Ca:0.0006-0.0012%, V:0.1-0.3%, Mo:0.1-0.6%,
RE:0.05-0.1%；N:0.01-0.08%, Nb:0.1-0.25%, surplus are Fe and inevitable impurity element.
Preferably, the alloy compositions meet following formula:
1.5≤(V%+Nb%+Cr%)/(formula of N%+C%)≤3 1
The formula of Al%/Mg%≤3 2
0.02≤(Ca%+Mg%)/S%≤0.15 formula 3
Easy-cutting untempered steel of the invention is manufactured by following processing step:
(1) smelting and alloying, electric furnace smelting, tapping, LF external refining, to guarantee Cutting free inclusion morphology in steel,
In external refining using first addition Ca-Si line is handled into steel, then Mg-Al-RE intermediate alloy is added into steel and carries out
Processing；
(2) it casts under protective atmosphere, obtains ingot casting；
(3) it is forged after 1050-1150 DEG C of Homogenization Treatments, it is air-cooled after forging；
(4) tempering is carried out.Preferably, double tempering is carried out, first time tempering temperature is 450~550 DEG C, the time
0.5-5h, second of tempering temperature are 180-220 DEG C, time 0.5-3h.
The tensile strength of easy-cutting untempered steel of the present invention up to 1200MPa or more, yield strength up to 800Mpa with
On, and Chong hits Ren≤48J/cm2, hardness is up to 45HRC or more, and compared with mould steel 40Cr commonly used in the art, cutting
Performance is obviously improved.
The effect of each element of the present invention:
C:0.35-0.55%
Main austenizer, main intensified element, as phosphorus content improves, the structural hardening effect of steel is further
Significantly, in order to guarantee the precipitations of enough carbide, the C content in the present invention should be not less than 0.35%.
Si:1.5-2.2%
Si can be used as deoxidant element, and carbide is not formed in steel, and can be solid-solution in ferrite influences the strength character of steel.
Steel can promote steel to generate post-curing effect, improve the elevated temperature strength of steel, and can effectively improve after 450~550 DEG C of tempering
The oxidation resistance of steel at high temperature improves the corrosion resistance among oxide isolation.In order to obtain above-mentioned performance, controlled in the present invention
Si content processed is 1.5-2.2%.
Mn:1.8-2.4%
Mn plays the role of solution strengthening in steel, while can increase the harden ability of steel.
S:0.05-0.15%
S element is added, makes to form MnS field trash in steel, is mingled with on-deformable oxide and cures
Object wraps up and can increase the machinability of steel.
Mg:0.001-0.03%
By the compound addition deoxidation of Mg-Al-RE, the content of oxygen in steel can be reduced to lower content, and in steel
In liquid process of setting, MgO-Al2O3Tiny magnesium aluminate spinel type impurity is formed, it, can be with as the forming core core of sulfide
Promote the precipitation of sulfide and be uniformly distributed, while change oxide morphology can be played, forming magnesia is that core manganese sulfide is
The spindle of coating is mingled with, to improve free-cutting machinability.Meanwhile Mg and Al, Si, Ca are formed together MgO-SiO2-CaO-
Al2O3Composite balls compound substantially improves the cutting ability of alloy.In addition, magnesium aluminate spinel type impurity is alternatively arranged as carbide
Core is precipitated, plays the role of refined carbides, thus the whole obdurability for improving steel.
Al:
It is added as deoxidant element, complex deoxidization can be played the role of together with Mg, be formed simultaneously the improvement of composite balls compound
Cutting ability.Al is easily formed tiny AlN particle obstruction austenite grain coarsening, but the addition of excess Al in steel simultaneously
The toughness for the steel that will affect.
The Mg that is preferably added in the present invention, Al content meet Al%/Mg%≤3, it is possible thereby to guarantee to close the toughness of alloy
It meets the requirements.
Ca:0.0006-0.0012%
During solidification of molten steel, the oxidation product of calcium can promote the precipitation of sulfide as sulfide forming core core
With being uniformly distributed for sulfide.MgO-SiO is formed together with Al, Si, Mg simultaneously2-CaO-Al2O3Composite balls compound, thus improves
Cutting ability.
The present inventor has surprisingly found that Mg, Ca, S content in control steel meet 0.02≤(Ca%+
When Mg%)/S%≤0.15, the cutting ability of steel improves significantly, this may be with the forming amounts of composite oxides to vulcanization
The control of object form is related.
Cr:0.5-0.9%, V:0.1-0.3%, Nb:0.1-0.25%
V, Cr, Nb are that strong carbide and nitride forming element have preferably each other when the addition of these three elements compoundings
When proportion, the structural hardening effect of steel can further improve.When meeting following relational expression,
1.5≤(V%+Nb%+Cr%)/()≤3 N%+C%
It can guarantee the precipitation of sufficient amount carbide in steel, to meet changing firmness requirements.
Mo:0.1-0.6%
Mo is important carbide former, especially hard in the steel that can greatly improve tempering by temper hardening
Degree improves steel wearability.
In manufacturing process of the invention, handled using Ca-Si line is first added into steel when external refining, then Xiang Gang
Middle addition Mg-Al-RE intermediate alloy is handled.By controlling the order of addition of trace alloying element, can obtain desired
Inclusion morphology, to reach thinning microstructure, and improve the effect of cutting ability.
In tempering process, passes through 450~550 DEG C of high tempering first, promote the precipitation of carbide, effectively improve steel
The hardness of material, then the stress of the lonneal reduction steel by 180-220 DEG C, improve toughness, to obtain obdurability satisfaction
It is required that mould steel.
Specific embodiment
Embodiment 1-6, comparative example 1-6 concrete component see the table below 1, and follow the steps below preparation:
Smelting and alloying, electric furnace smelting, tapping, LF external refining.To guarantee Cutting free inclusion morphology in steel, in furnace
Using first into steel, addition Ca-Si line is handled when outer refining, then it is added at Mg-Al-RE intermediate alloy into steel
Reason；
It casts under protective atmosphere, obtains ingot casting；
It is forged after 1050-1150 DEG C of Homogenization Treatments, it is air-cooled after forging；
Carry out tempering.Preferably, double tempering is carried out, first time tempering temperature is 450~550 DEG C, time 0.5-
5h, second of tempering temperature are 180-220 DEG C, time 0.5-3h.
To double tempering treated sample 1-6, B1-B8, mechanical property is carried out, and record continuous using same tool
Tool abrasion after cutting 30min, evaluates its cutting ability with this.Concrete outcome is referring to table 2.
As can be seen from Table 2, B1 causes hardness to be substantially reduced due to lacking elements Mo, and B2 is caused by lacking elements RE
Hardness and Cutting free all significantly reduce, and B3, B4 cause hardness to significantly reduce due to being unsatisfactory for the requirement of formula 1.B5 is unsatisfactory for
Formula 3 and cause cutting ability to significantly reduce.B6 is unsatisfactory for formula 2 and causes intensity insufficient.
40Cr mould steel commonly used in the art is tested under the same conditions, the tool abrasion of 30min is
0.44mm, it is seen that the cutting ability of mould steel of the invention is obviously improved.
In addition, when producing the steel of 6 component of sample, the addition sequence of Ca, Mg when changing external refining first add into steel
Enter Mg-Al-RE intermediate alloy, be eventually adding Ca-Si line, implements identical hot-working and heat treatment process later, thus to obtain
Comparative example B7.Cutting ability test is carried out to B7, it is found that the tool abrasion of its 30min up to 0.35mm, is much higher than sample 6.By
This is as it can be seen that Mg, Ca addition sequence in the application are also vital.
The present invention is exemplarily described above, it is clear that present invention specific implementation is not limited by aforesaid way, only
The various improvement that the inventive concept and technical scheme of the present invention carry out are used, or not improved directly apply to other occasions
, it is within the scope of the present invention.
Claims (3)
1. a kind of non-tempering easy cutting die steel has following component by percentage to the quality:
C:0.35-0.55%, Si:1.5-2.2%, Mn:2.1-2.4%, Cr:0.5-0.9%, S:0.05-0.15%, Mg:
0.001-0.015%, Al:0.01-0.05%, Ca:0.0006-0.0012%, V:0.1-0.3%, Mo:0.1-0.6%, RE:
0.05-0.1%；N:0.01-0.08%, Nb:0.1-0.25%, surplus are Fe and inevitable impurity element；
And it meets following formula
1.5≤(V%+Nb%+Cr%)/(N%+C%)≤3 formula 1
The formula of Al%/Mg% >=32
0.02≤(Ca%+Mg%)/S%≤0.15 formula 3
The steel follows the steps below preparation,
(1) smelting and alloying, electric furnace smelting, tapping, LF external refining, to guarantee Cutting free inclusion morphology in steel, in furnace
Using the first addition Ca-Si line into steel when outer refining, then Mg-Al-RE intermediate alloy is added into steel and is handled；
(2) it casts under protective atmosphere, obtains ingot casting；
(3) it is forged after 1050-1150 DEG C of Homogenization Treatments, it is air-cooled after forging；
(4) tempering is carried out.
2. non-tempering easy cutting die steel according to claim 1, it is characterised in that: the tensile strength of the steel reaches
1200MPa or more, yield strength reach 800MP a or more, and impact flexibility >=48J/cm2, hardness reach 45HRC or more.
3. non-tempering easy cutting die steel according to claim 1, it is characterised in that: the tempering step of step (4) is divided to two
Secondary progress, first time tempering temperature are that 450~550 DEG C, time 0.5-5h, second tempering temperatures are 180-220 DEG C, the time
0.5-3h。
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| CN201811105774.5A CN109022697B (en) | 2018-09-21 | 2018-09-21 | A kind of Micro Alloying mould steel and preparation method thereof |
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| CN110055450B (en) * | 2019-04-18 | 2021-04-20 | 石钢京诚装备技术有限公司 | Smelting method of non-quenched and tempered steel |
| CN114015937B (en) * | 2021-10-20 | 2023-01-31 | 石家庄钢铁有限责任公司 | Free-cutting non-quenched and tempered steel and production method thereof |
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| US6764645B2 (en) * | 2001-11-28 | 2004-07-20 | Diado Steel Co., Ltd. | Steel for machine structural use having good machinability and chip-breakability |
| CN100537817C (en) * | 2008-03-17 | 2009-09-09 | 莱芜钢铁股份有限公司 | Easy-cutting untempered steel and manufacture method thereof |
| CN101302601A (en) * | 2008-07-01 | 2008-11-12 | 上海大学 | High-strength tough large-cross section non-quenched and tempered steel rod and preparation thereof |
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Effective date of registration: 20190807 Address after: 331200 Dongcun Residential Committee, Daqiao Street Office, Zhangshu City, Yichun City, Jiangxi Province Patentee after: Zhangshu Xinglonggao New Materials Co., Ltd. Address before: 331200 Dongcun Community, Daqiao Township, Zhangshu City, Yichun City, Jiangxi Province Patentee before: Jiangxi Zhangshu Xinglong Special Steel Co., Ltd. |
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