CN107435124A - High tungsten ledeburite pinion steel of hard high-wearing feature and preparation method thereof - Google Patents
High tungsten ledeburite pinion steel of hard high-wearing feature and preparation method thereof Download PDFInfo
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- CN107435124A CN107435124A CN201610359954.0A CN201610359954A CN107435124A CN 107435124 A CN107435124 A CN 107435124A CN 201610359954 A CN201610359954 A CN 201610359954A CN 107435124 A CN107435124 A CN 107435124A
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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
-
- 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
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D1/00—General methods or devices for heat treatment, e.g. annealing, hardening, quenching or tempering
- C21D1/26—Methods of annealing
- C21D1/28—Normalising
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D9/00—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor
- C21D9/32—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor for gear wheels, worm wheels, or the like
-
- 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
- C22C38/02—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
- C22C38/08—Ferrous alloys, e.g. steel alloys containing nickel
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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
- C22C38/12—Ferrous alloys, e.g. steel alloys containing tungsten, tantalum, molybdenum, vanadium, or niobium
-
- 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
- C21D2211/007—Ledeburite
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P10/00—Technologies related to metal processing
- Y02P10/20—Recycling
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Abstract
A kind of high tungsten ledeburite pinion steel of hard high-wearing feature and preparation method thereof, belongs to powder metallurgical technology, is made up of the raw material of following mass percent, C 1.8%;Si 0.5%;Mn 0.25%;S 0.015%;P 0.025%;Cr 2.5%;Mo 1.25%;V 0.8%;Nb 0.16%;RE 0.05%;Ni 0.12%;W 0.30%;Remaining is Fe and impurity.The cold work die steels such as alternative Cr12MoV, D2 steel class of the present invention, improve mould toughness and wearability, service life greatly improves, so as to reduce use cost, expand use range, can effectively solve under the Special use environment such as heavy shock loads, operating rate height, high precision and long service life the problems such as poor toughness tipping or fracture, not wear-resisting.Meet a variety of high-mechanics, the use demand of high rotating speed occasion.
Description
Technical field
The invention belongs to powder metallurgical technology, is related to a kind of pinion steel and preparation method thereof, more particularly to one kind
High tungsten ledeburite pinion steel of hard high-wearing feature and preparation method thereof.
Background technology
China Gear industry is developed rapidly in Tenth Five-Year Plan Period:The annual value of production of gear industry in 2005 was by 2000
24,000,000,000 yuan increase to 68,300,000,000 yuan, annual compound growth rate 23.27%, it has also become largest row in Chinese mechanical basic part
Industry.For the market demand and production scale, China Gear industry exceedes Italy in global ranking, occupies the 4th, the world.
Gear and its gear product are the important foundation parts of mechanized equipment, the primary drive of most complete set of machines
Part is all gear drive.With the high speed development of national economy, the whole industry year gross sales amount broken through hundred billion yuan, form enterprise
Industry is polynary and deposits, the industry structures of joint development.Wherein, leading enterprise, leading enterprise have turned into promotes trade management level, production
The horizontal important force with Innovation Ability of product technical quality, it is that China is turned into gear from gear manufacture big country
Manufacturing power is made that outstanding contributions.
According to (China Gear industry production and marketing requirement forecasting and transition and upgrade analysis report) display China Gear transmission industry
It is developed rapidly the Eleventh Five-Year Plan period, the total industrial output value of 2005-2010 China Gear industries increases year by year, and together
Than amplification more than 20%.Whole gear industry in 2010 realizes 946.35 hundred million yuan of total industrial output value, and gear whole industry market needs
Ask more than 140,000,000,000 yuan, world rankings second.From the point of view of each side factor such as scale and sales volume, during gear industry already turns into
" leading " the level industry in state's machinery spare part in common use basic part field.It is big that China has become qualified world's gear manufacture
State.
D2 steel is a kind of high carbon and chromium ledeburite type cold work die steel, and air cooling can harden.It is U.S. ASTMA681-
94《Alloy tool steel technical conditions》In a grade of steel, included within 1985 China standard GB 1299-85《Alloy tool steel
Technical conditions》, but Mo in D2 steel and V content double the above than Crl2MoV steel.Therefore, introduced in GB1299-85
During D2 steel, it is set to Cr12Mo1V1 by China's grade of steel representation.D2 steel is a kind of cold work die steel of international type, almost
All advanced industrial countries all incorporate it the national standard of oneself, such as:BD2 steel in Britain BS4659;Japan
SKD11 steel in JIS4404;X155CrVMo12l steel in German DIN17350;In French A35-580
Z160CDV12 steel.It is characterized in:Phosphorus content is high, and alloying element is more, substantial amounts of carbide in steel be present, and fragility is big, and deformation is anti-
Power is big, forging and temperature range is narrower during hot rolling, thermomechanical processing poor performance and decarburization tends to big.But manufactured after becoming a useful person with it
Mould has high rigidity, medium toughness and excellent anti-deformation, therefore service life is grown, and since the advent of the world is deep by foreign countries always
Each cold-working mould producer is favored.It is serious that carbide segregation easily occurs in D2 steel, causes directionality deformation and toughness relatively low, Gao Ying
Easily occur microscopic nicks at power, situation about being easily broken after heat treatment.
The content of the invention
For the present invention carbide segregation, which easily occurs, in order to solve existing D2 cold work die steels for the present invention seriously causes toughness
Relatively low the problem of microscopic nicks occur and being broken, there is provided a kind of high tungsten ledeburite pinion steel of hard high-wearing feature and its system
Preparation Method.
The technical scheme is that:A kind of high tungsten ledeburite pinion steel of hard high-wearing feature and preparation method thereof, its
It is characterised by:It is made up of the raw material of following mass percent, C 1.8%;Si 0.5% ;Mn 0.25% ;S 0.015% ;P
0.025% ;Cr 2.5% ;Mo 1.25% ;V 0.8% ;Nb 0.16% ;RE 0.05% ;Ni 0.12% ;W 0.30% ;Its
Remaining is Fe and impurity.
A kind of high tungsten ledeburite pinion steel of hard high-wearing feature and preparation method thereof, it is characterised in that:Including following step
Suddenly:
(1) raw scrap material is added into melting in electric arc furnaces, smelting temperature is 1300 DEG C, and raw material and deoxidation are added in fusion process
Agent, double refining is then carried out by ladle refining furnace and vacuum degassing furnace;
(2) ingot mould is preheating to 320 DEG C, cast temperature is 1400 DEG C, is come out of the stove after insulation after demoulding insulation slow cooling;
(3) steel ingot is put into electroslag remelting device as consutrode and carries out double refining, reduce gas and inclusion content,
Obtain composition uniformly, the high ingot casting of dense structure, quality;
(4) 720 DEG C of ingot casting preheating temperature, heating-up temperature are 1000 DEG C, and initial forging temperature is 1020 DEG C, and final forging temperature is 800 DEG C,
Forging ratio is 5, obtains forged steel pieces;
(5) forged steel pieces are incubated 2 h at 800 DEG C, after being then furnace-cooled to 700 DEG C of isothermal 4h, are furnace-cooled to less than 500 DEG C skies of coming out of the stove
It is cold;
(6) 700 DEG C are then slowly warming up to, first time preheating is carried out after being incubated 45min, rises to 900 DEG C after samming, then be incubated
20min carries out second and preheated, and is finally warming up to 1000 DEG C, is incubated 30min, air cooling of coming out of the stove;Finally 2h is incubated at 200 DEG C to enter
Row tempering.
Modulus m=5, tooth number Z=36 of the gear.
The weak carburizing atmosphere Carburization Treatment in surface is first done after the gear forming, then does surface hardening processing.
The gear needs to use normalizing after the completion of Quenching Treatment, and carries out high tempering processing with 720 DEG C.
The gear needs to use milled processed after completing to be heat-treated.
Beneficial effects of the present invention are:A kind of high tungsten ledeburite pinion steel of hard high-wearing feature proposed by the present invention and its
Preparation method, component is novel, and manufacturing process is rationally clear, high comprehensive performance of the present invention, alternative Cr12MoV, D2 steel class etc.
Cold work die steel, improves mould toughness and wearability, service life greatly improve, and so as to reduce use cost, expansion uses model
Enclose, can effectively solve poor toughness tipping or disconnected under the Special use environment such as heavy shock loads, operating rate height, high precision and long service life
The problems such as splitting, be not wear-resisting.In order to improve the case hardness of gear, case-carbonizing processing is carried out after gear forming, after the completion of carburizing
Carry out surface hardening processing, improve the hardness of the gear teeth and the surface strength of the gear teeth, reduce the abrasion of the flank of tooth, by normalizing and
Temper, the interior mechanics performance of gear is improved, its toughness and fatigue strength are greatly improved, at whole heat
After the completion of reason, milled processed is additionally used, the mechanical property on surface is improved, has especially been passivated the stress on surface, gear
Service life is greatly improved, and meets a variety of high-mechanics, the use demand of high rotating speed occasion.
Embodiment
The invention will be further described below:
A kind of high tungsten ledeburite pinion steel of hard high-wearing feature and preparation method thereof, by the raw material group of following mass percent
Into C 1.8%;Si 0.5% ;Mn 0.25% ;S 0.015% ;P 0.025% ;Cr 2.5% ;Mo 1.25% ;V 0.8% ;
Nb 0.16% ;RE 0.05% ;Ni 0.12% ;W 0.30% ;Remaining is Fe and impurity.
A kind of high tungsten ledeburite pinion steel of hard high-wearing feature and preparation method thereof, comprises the following steps:
(1) raw scrap material is added into melting in electric arc furnaces, smelting temperature is 1300 DEG C, and raw material and deoxidation are added in fusion process
Agent, double refining is then carried out by ladle refining furnace and vacuum degassing furnace;
(2) ingot mould is preheating to 320 DEG C, cast temperature is 1400 DEG C, is come out of the stove after insulation after demoulding insulation slow cooling;
(3) steel ingot is put into electroslag remelting device as consutrode and carries out double refining, reduce gas and inclusion content,
Obtain composition uniformly, the high ingot casting of dense structure, quality;
(4) 720 DEG C of ingot casting preheating temperature, heating-up temperature are 1000 DEG C, and initial forging temperature is 1020 DEG C, and final forging temperature is 800 DEG C,
Forging ratio is 5, obtains forged steel pieces;
(5) forged steel pieces are incubated 2 h at 800 DEG C, after being then furnace-cooled to 700 DEG C of isothermal 4h, are furnace-cooled to less than 500 DEG C skies of coming out of the stove
It is cold;
(6) 700 DEG C are then slowly warming up to, first time preheating is carried out after being incubated 45min, rises to 900 DEG C after samming, then be incubated
20min carries out second and preheated, and is finally warming up to 1000 DEG C, is incubated 30min, air cooling of coming out of the stove;Finally 2h is incubated at 200 DEG C to enter
Row tempering.
Gear made from a kind of high tungsten ledeburite pinion steel preparation method of hard high-wearing feature, modulus m=5 of gear, tooth
Number Z=36;The weak carburizing atmosphere Carburization Treatment in surface is first done after gear forming, then does surface hardening processing;Gear is in Quenching Treatment
After the completion of need to use normalizing, and carry out high tempering processing with 720 DEG C;Gear is needed after completing to be heat-treated using at grinding
Reason.
Instant component is novel, and manufacturing process is rationally clear, high comprehensive performance of the present invention, alternative Cr12MoV, D2
The cold work die steels such as steel class, improve mould toughness and wearability, service life greatly improve, and so as to reduce use cost, expand
Use range, can effectively solve poor toughness under the Special use environment such as heavy shock loads, operating rate height, high precision and long service life and collapse
Sword or fracture, it is not wear-resisting the problems such as.In order to improve the case hardness of gear, case-carbonizing processing, carburizing are carried out after gear forming
After the completion of carry out surface hardening processing, improve the hardness of the gear teeth and the surface strength of the gear teeth, reduce the abrasion of the flank of tooth, pass through
Normalizing and temper, the interior mechanics performance of gear is improved, its toughness and fatigue strength are greatly improved, whole
After the completion of individual heat treatment, milled processed is additionally used, the mechanical property on surface is improved, has especially been passivated the stress on surface,
The service life of gear is greatly improved, and meets a variety of high-mechanics, the use demand of high rotating speed occasion.
Claims (6)
- A kind of 1. high tungsten ledeburite pinion steel of hard high-wearing feature and preparation method thereof, it is characterised in that:By following quality hundred Divide the raw material composition of ratio, C 1.8%;Si 0.5% ;Mn 0.25% ;S 0.015% ;P 0.025% ;Cr 2.5% ;Mo 1.25% ;V 0.8% ;Nb 0.16% ;RE 0.05% ;Ni 0.12% ;W 0.30% ;Remaining is Fe and impurity.
- A kind of 2. high tungsten ledeburite pinion steel of hard high-wearing feature and preparation method thereof, it is characterised in that:Comprise the following steps:(1) raw scrap material is added into melting in electric arc furnaces, smelting temperature is 1300 DEG C, and raw material and deoxidation are added in fusion process Agent, double refining is then carried out by ladle refining furnace and vacuum degassing furnace;(2) ingot mould is preheating to 320 DEG C, cast temperature is 1400 DEG C, is come out of the stove after insulation after demoulding insulation slow cooling;(3) steel ingot is put into electroslag remelting device as consutrode and carries out double refining, reduce gas and inclusion content, Obtain composition uniformly, the high ingot casting of dense structure, quality;(4) 720 DEG C of ingot casting preheating temperature, heating-up temperature are 1000 DEG C, and initial forging temperature is 1020 DEG C, and final forging temperature is 800 DEG C, Forging ratio is 5, obtains forged steel pieces;(5) forged steel pieces are incubated 2 h at 800 DEG C, after being then furnace-cooled to 700 DEG C of isothermal 4h, are furnace-cooled to less than 500 DEG C skies of coming out of the stove It is cold;(6) 700 DEG C are then slowly warming up to, first time preheating is carried out after being incubated 45min, rises to 900 DEG C after samming, then be incubated 20min carries out second and preheated, and is finally warming up to 1000 DEG C, is incubated 30min, air cooling of coming out of the stove;Finally 2h is incubated at 200 DEG C to enter Row tempering.
- 3. gear made from the high tungsten ledeburite pinion steel preparation method of a kind of hard high-wearing feature described in claim 2, its It is characterised by:Modulus m=5, tooth number Z=36 of the gear.
- 4. gear made from the high tungsten ledeburite pinion steel preparation method of a kind of hard high-wearing feature described in claim 2, its It is characterised by:The weak carburizing atmosphere Carburization Treatment in surface is first done after the gear forming, then does surface hardening processing.
- 5. gear made from the high tungsten ledeburite pinion steel preparation method of a kind of hard high-wearing feature described in claim 2, its It is characterised by:The gear needs to use normalizing after the completion of Quenching Treatment, and carries out high tempering processing with 720 DEG C.
- 6. gear made from the high tungsten ledeburite pinion steel preparation method of a kind of hard high-wearing feature described in claim 2, its It is characterised by:The gear needs to use milled processed after completing to be heat-treated.
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Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN112382354A (en) * | 2020-11-27 | 2021-02-19 | 北京京航计算通讯研究所 | Cr12MoV material hardness prediction method and device |
CN114939664A (en) * | 2022-05-26 | 2022-08-26 | 南通新思迪机电有限公司 | High-strength wear-resistant gear machining process |
-
2016
- 2016-05-27 CN CN201610359954.0A patent/CN107435124A/en active Pending
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN112382354A (en) * | 2020-11-27 | 2021-02-19 | 北京京航计算通讯研究所 | Cr12MoV material hardness prediction method and device |
CN114939664A (en) * | 2022-05-26 | 2022-08-26 | 南通新思迪机电有限公司 | High-strength wear-resistant gear machining process |
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