CN106636567A - Method for improving through hardening property of G20CrNiMoA - Google Patents
Method for improving through hardening property of G20CrNiMoA Download PDFInfo
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- CN106636567A CN106636567A CN201610910476.8A CN201610910476A CN106636567A CN 106636567 A CN106636567 A CN 106636567A CN 201610910476 A CN201610910476 A CN 201610910476A CN 106636567 A CN106636567 A CN 106636567A
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- g20crnimoa
- raising
- hardening
- steel billet
- quenching treatment
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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
-
- 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
- C21D6/00—Heat treatment of ferrous alloys
- C21D6/004—Heat treatment of ferrous alloys containing Cr and Ni
-
- 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
- C21D6/00—Heat treatment of ferrous alloys
- C21D6/005—Heat treatment of ferrous alloys containing Mn
-
- 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
- C21D6/00—Heat treatment of ferrous alloys
- C21D6/008—Heat treatment of ferrous alloys containing Si
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/02—Ferrous alloys, e.g. steel alloys containing silicon
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/04—Ferrous alloys, e.g. steel alloys containing manganese
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
- C22C38/40—Ferrous alloys, e.g. steel alloys containing chromium with nickel
- C22C38/42—Ferrous alloys, e.g. steel alloys containing chromium with nickel with copper
-
- 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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- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Mechanical Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Physics & Mathematics (AREA)
- Thermal Sciences (AREA)
- Crystallography & Structural Chemistry (AREA)
- Heat Treatment Of Steel (AREA)
- Heat Treatment Of Articles (AREA)
Abstract
The invention discloses a method for improving the through hardening property of G20CrNiMoA. The G20CrNiMoA comprises the following elements in percentages by weight: 0.17-0.23% of C, 0.60-0.90% of Mn, 0.15-0.40% of Si, less than or equal to 0.020% of S, less than or equal to 0.020% of P, 0.35-0.65% of Cr, 0.4-0.7% of Ni, 0.15-0.3% of Mo, less than or equal to 0.25% of Cu and the balance of Fe. In a smelting process, 25-45ppm of an element B is added, so that the through hardening property of carburizing bearing steel is remarkably improved, the performance requirement on working conditions is met, and the method has good economical and social benefits, is suitable for being popularized and used, and can meet the using requirements on the working environments thereof.
Description
Technical field
The present invention relates to a kind of method for improving through hardening performance, specially a kind of side of raising G20CrNiMoA through hardening performances
Method, belongs to materials application technical field.
Background technology
The design feature of carburizing bearing steel and condition of work require that bearing parts must possess high hardness, wearability, connect
Tactile fatigue strength, good toughness, dimensional stability, anti-corrosion and cold and hot working performance, bearing steel operationally subjects greatly
Pressure and frictional force, it requires that bearing steel has a height and uniform hardness and wearability, and high elastic limit, to bearing
The requirement such as the uniformity of the chemical composition of steel, the content of non-metallic inclusion and distribution, the distribution of carbide is all very strict, is
One of most stringent of steel grade is required in the production of all iron and steel, with the development of China's mechanization, to the demand of bearing steel also therewith
Increase.
And bearing steel hardenability that existing China is produced is relatively low, in quenching cooling procedure, the cooling of surface and center portion
Speed has larger difference, causes to be partially converted to martensite more than critical cooling rate, and is less than the heart of critical cooling rate
Portion can not be transformed into martensite, it is internal due to expand with heat and contract with cold it is uneven cause internal stress, deformation of products or cracking are made, while entering
During row temper, a temper is only carried out, a part can only be eliminated because rapidly cooling down caused residual stress, because
The toughness of this material cannot be improved with flexibility, be can not meet and obtain required by condition of work performance.
The content of the invention
The purpose of the present invention is that and a kind of raising G20CrNiMoA through hardening performances is provided to solve the above problems
Method, meets the use requirement under complex work environment.
The present invention is achieved through the following technical solutions above-mentioned purpose, a kind of side of raising G20CrNiMoA through hardening performances
Method, in terms of G20CrNiMoA percentage by weights, including C：0.17～0.23%, Mn：0.60～0.90%, Si：0.15～
0.40%th, S：≤ 0.020%, P：≤ 0.020%, Cr：0.35～0.65%, Ni：0.4～0.7%, Mo：0.15～0.3%,
Cu：≤ 0.25% and surplus Fe；
Its method and step is as follows：
Step A, the melting in antivacuum electric furnace of required element is taken, 1580～1640 DEG C of smelting temperature, in fusion process
Adjust the content of each element so as to which weight ratio meets design requirement, is smelted into solution；
Step B, by the melting solution in step A in condensation, allocate the element B of 25～45ppm into, form steel billet；
Step C, the firm base formed in step B is carried out into first time Quenching Treatment, and processes 30min under hardening heat,
Then it is cooled to room temperature in air；
Step D, the steel billet cooled down in step C is carried out into second Quenching Treatment, and processes 20min under hardening heat,
Then it is cooled to room temperature in air；
Step E, will be tempered through the steel billet of Quenching Treatment twice in step C, 150～200 DEG C of temperature, processed
1h is subsequently cooled to room temperature, that is, complete the raising to G20CrNiMoA through hardening performances.
Preferably, in step B, element B be smelted into the melting solution after solution at the uniform velocity implantation step A carry out it is cold
It is solidifying.
Preferably, in step C, the temperature control of first time Quenching Treatment is at 860～900 DEG C.
Preferably, in step D, the temperature control of second Quenching Treatment is at 780～810 DEG C.
Preferably, in step C and step D, critical cooling rate of speed when being cooled down more than steel billet.
Preferably, in step E, 2-3 tempering is carried out to steel billet, the temperature of tempering keeps certain.
The invention has the beneficial effects as follows：The method that this kind improves G20CrNiMoA through hardening performances, adds in smelting process
The B element of 25～45ppm, carries out the speed quenched when cooling down more than critical cooling rate, while carrying out multiple temper, shows
The quenching degree for improving carburizing bearing steel is write, its condition of work is met and is required performance, there is good economic benefit and social benefit, fitted
Conjunction is promoted the use of.
Specific embodiment
Below in conjunction with embodiments of the invention, the technical scheme in the embodiment of the present invention is clearly and completely retouched
State, it is clear that described embodiment is only a part of embodiment of the invention, rather than the embodiment of whole.Based on the present invention
In embodiment, the every other enforcement that those of ordinary skill in the art are obtained under the premise of creative work is not made
Example, belongs to the scope of protection of the invention.
Embodiment one：
A kind of method of raising G20CrNiMoA through hardening performances, its method and step is as follows：
Step A, take in terms of G20CrNiMoA percentage by weights, including C：0.17%th, Mn：0.60%th, Si：0.15%th, S：
0.020%th, P：0.020%th, Cr：0.35%th, Ni：0.4%th, Mo：0.15%th, Cu：0.25% and surplus Fe in antivacuum electricity
Melting in stove, 1580～1640 DEG C of smelting temperature adjusts the content of each element so as to which weight ratio meets design in fusion process
Require, be smelted into solution；
Step B, by the melting solution in step A in condensation, allocate the element B of 25ppm into, form steel billet；
Step C, the firm base formed in step B is carried out into first time Quenching Treatment, and processes 30min under hardening heat,
Then it is cooled to room temperature in air；
Step D, the steel billet cooled down in step C is carried out into second Quenching Treatment, and processes 20min under hardening heat,
Then it is cooled to room temperature in air；
Step E, will be tempered through the steel billet of Quenching Treatment twice in step C, 150～200 DEG C of temperature, processed
1h is subsequently cooled to room temperature, that is, complete the raising to G20CrNiMoA through hardening performances.
In step B, element B is smelted into the melting solution after solution at the uniform velocity implantation step A and is condensed, described
In step C, the temperature control of first time Quenching Treatment at 860～900 DEG C, in step D, the temperature of second Quenching Treatment
At 780～810 DEG C, in step C and step D, speed when being cooled down is more than the critical cooling rate of steel billet, institute for control
In stating step E, 2-3 tempering is carried out to steel billet, the temperature of tempering keeps certain；
Embodiment two：
A kind of method of raising G20CrNiMoA through hardening performances, its method and step is as follows：
Step A, take in terms of G20CrNiMoA percentage by weights, including C：0.20%th, Mn：0.75%th, Si：0.25%th, S：
0.015%th, P：0.015%th, Cr：0.50%th, Ni：0.5%th, Mo：0.20%th, Cu：0.20% and surplus Fe in antivacuum electricity
Melting in stove, 1580～1640 DEG C of smelting temperature adjusts the content of each element so as to which weight ratio meets design in fusion process
Require, be smelted into solution；
Step B, by the melting solution in step A in condensation, allocate the element B of 35ppm into, form steel billet；
Step C, the firm base formed in step B is carried out into first time Quenching Treatment, and processes 30min under hardening heat,
Then it is cooled to room temperature in air；
Step D, the steel billet cooled down in step C is carried out into second Quenching Treatment, and processes 20min under hardening heat,
Then it is cooled to room temperature in air；
Step E, will be tempered through the steel billet of Quenching Treatment twice in step C, 150～200 DEG C of temperature, processed
1h is subsequently cooled to room temperature, that is, complete the raising to G20CrNiMoA through hardening performances.
In step B, element B is smelted into the melting solution after solution at the uniform velocity implantation step A and is condensed, described
In step C, the temperature control of first time Quenching Treatment at 860～900 DEG C, in step D, the temperature of second Quenching Treatment
At 780～810 DEG C, in step C and step D, speed when being cooled down is more than the critical cooling rate of steel billet, institute for control
In stating step E, 2-3 tempering is carried out to steel billet, the temperature of tempering keeps certain；
Embodiment three：
A kind of method of raising G20CrNiMoA through hardening performances, its method and step is as follows：
Step A, take in terms of G20CrNiMoA percentage by weights, including C：0.23%th, Mn：0.90%th, Si：0.40%th, S：
0.010%th, P：0.010%th, Cr：0.65%th, Ni：0.7%th, Mo：0.3%th, Cu：0.15% and surplus Fe in antivacuum electric furnace
Middle melting, 1580～1640 DEG C of smelting temperature adjusts the content of each element in fusion process so as to which weight ratio meets design will
Ask, be smelted into solution；
Step B, by the melting solution in step A in condensation, allocate the element B of 45ppm into, form steel billet；
Step C, the firm base formed in step B is carried out into first time Quenching Treatment, and processes 30min under hardening heat,
Then it is cooled to room temperature in air；
Step D, the steel billet cooled down in step C is carried out into second Quenching Treatment, and processes 30min under hardening heat,
Then it is cooled to room temperature in air；
Step E, will be tempered through the steel billet of Quenching Treatment twice in step C, 150～200 DEG C of temperature, processed
1h is subsequently cooled to room temperature, that is, complete the raising to G20CrNiMoA through hardening performances.
In step B, element B is smelted into the melting solution after solution at the uniform velocity implantation step A and is condensed, described
In step C, the temperature control of first time Quenching Treatment at 860～900 DEG C, in step D, the temperature of second Quenching Treatment
At 780～810 DEG C, in step C and step D, speed when being cooled down is more than the critical cooling rate of steel billet, institute for control
In stating step E, 2-3 tempering is carried out to steel billet, the temperature of tempering keeps certain；
According to the method that embodiment one, embodiment two and embodiment three improve G20CrNiMoA through hardening performances, result of the test
As shown in Table 1,
Add the B element of 25～45ppm in smelting process, significantly improve the quenching degree of carburizing bearing steel, meet its work
Make condition and require performance, there is good economic benefit and social benefit, be adapted to promote the use of and disclosure satisfy that making for its working environment
With requiring.
It is obvious to a person skilled in the art that the invention is not restricted to the details of above-mentioned one exemplary embodiment, Er Qie
In the case of spirit or essential attributes without departing substantially from the present invention, the present invention can be in other specific forms realized.Therefore, no matter
From the point of view of which point, embodiment all should be regarded as exemplary, and be nonrestrictive, the scope of the present invention is by appended power
Profit is required rather than described above is limited, it is intended that all in the implication and scope of the equivalency of claim by falling
Change is included in the present invention.Any embodiment mark in claim should not be considered as and limit involved claim.
Moreover, it will be appreciated that although this specification is been described by according to embodiment, not each embodiment is only wrapped
Containing an independent technical scheme, this narrating mode of specification is only that for clarity those skilled in the art should
Using specification as an entirety, the technical scheme in each embodiment can also Jing it is appropriately combined, form those skilled in the art
Understandable other embodiment.
Claims (6)
1. a kind of method of raising G20CrNiMoA through hardening performances, it is characterised in that in terms of G20CrNiMoA percentage by weights, bag
Include C：0.17～0.23%, Mn：0.60～0.90%, Si：0.15～0.40%, S：≤ 0.020%, P：≤ 0.020%, Cr：
0.35～0.65%, Ni：0.4～0.7%, Mo：0.15～0.3%, Cu：≤ 0.25% and surplus Fe；
Its method and step is as follows：
Step A, the melting in antivacuum electric furnace of required element is taken, 1580～1640 DEG C of smelting temperature is adjusted in fusion process
The content of each element so as to which weight ratio meets design requirement, is smelted into solution；
Step B, by the melting solution in step A in condensation, allocate the element B of 25～45ppm into, form steel billet；
Step C, the firm base formed in step B is carried out into first time Quenching Treatment, and 30min is processed under hardening heat, then
Room temperature is cooled in air；
Step D, the steel billet cooled down in step C is carried out into second Quenching Treatment, and 20min is processed under hardening heat, then
Room temperature is cooled in air；
Step E, will be tempered through the steel billet of Quenching Treatment twice in step C, 150～200 DEG C of temperature, processed 1h right
After be cooled to room temperature, that is, complete the raising to G20CrNiMoA through hardening performances.
2. the method for a kind of raising G20CrNiMoA through hardening performances according to claim 1, it is characterised in that：The step
In B, element B is smelted into the melting solution after solution at the uniform velocity implantation step A and is condensed.
3. the method for a kind of raising G20CrNiMoA through hardening performances according to claim 1, it is characterised in that：The step
In C, the temperature control of first time Quenching Treatment is at 860～900 DEG C.
4. the method for a kind of raising G20CrNiMoA through hardening performances according to claim 1, it is characterised in that：The step
In D, the temperature control of second Quenching Treatment is at 780～810 DEG C.
5. the method for a kind of raising G20CrNiMoA through hardening performances according to claim 1, it is characterised in that：The step
In C and step D, critical cooling rate of speed when being cooled down more than steel billet.
6. the method for a kind of raising G20CrNiMoA through hardening performances according to claim 1, it is characterised in that：The step
In E, 2-3 tempering is carried out to steel billet, keep certain temperature.
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| Application Number | Priority Date | Filing Date | Title |
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| CN201610910476.8A CN106636567A (en) | 2016-10-19 | 2016-10-19 | Method for improving through hardening property of G20CrNiMoA |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115094327A (en) * | 2022-07-06 | 2022-09-23 | 中国科学院金属研究所 | Long-life carburizing bearing steel and preparation method thereof |
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2016
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| JPH03122219A (en) * | 1989-10-06 | 1991-05-24 | Nippon Steel Corp | Production of high strength steel tube for machine structural use having >=120kgf/mm2 tensile strength |
| CN102459678A (en) * | 2009-05-27 | 2012-05-16 | 住友金属工业株式会社 | Carburized component and manufacturing method therefor |
| CN101603119A (en) * | 2009-07-03 | 2009-12-16 | 马景怡 | Make the method for high-intensity high-tenacity steel plate with hot-rolled coil |
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| CN103451562A (en) * | 2013-08-29 | 2013-12-18 | 舞阳钢铁有限责任公司 | Quenched large-thickness easy-to-weld Z-direction high-strength steel plate for water and electricity and production method thereof |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115094327A (en) * | 2022-07-06 | 2022-09-23 | 中国科学院金属研究所 | Long-life carburizing bearing steel and preparation method thereof |
| CN115094327B (en) * | 2022-07-06 | 2024-03-26 | 中国科学院金属研究所 | Long-life carburized bearing steel and preparation method thereof |
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Application publication date: 20170510 |