CN105132800A - Car shaft steel and production method thereof - Google Patents
Car shaft steel and production method thereof Download PDFInfo
- Publication number
- CN105132800A CN105132800A CN201510231018.7A CN201510231018A CN105132800A CN 105132800 A CN105132800 A CN 105132800A CN 201510231018 A CN201510231018 A CN 201510231018A CN 105132800 A CN105132800 A CN 105132800A
- Authority
- CN
- China
- Prior art keywords
- production method
- heating
- normalizing
- axle
- axle steel
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Landscapes
- Heat Treatment Of Steel (AREA)
- Forging (AREA)
- Heat Treatment Of Articles (AREA)
Abstract
The present invention relates to car shaft steel and a production method thereof, the car shaft steel contains the following components by weight: 0.48-0.52% of C, 0.19-0.34% of Si, 0.64-0.86% of Mn, 0.005-0.014% of P, 0.001-0.006% of S, 0.015-0.040% of Nb, 0.018-0.035% of Als, and balance of iron and unavoidable impurities. The production method comprises the following steps: (1) car shaft forging; (2) first processing; (3) heat treatment comprising first normalizing, secondary normalizing and tempering; and (4) secondary processing. By use of niobium microalloying principle and combination of the car shaft forging and heat treatment process for optimization, the LZ50 car shaft grain fineness number can be significantly refined, the heat-treated car shaft organization comprises pearlite and ferrite, the actual grain fineness number is greater than or equal to 8.5, the heat-treated car shaft is free of mixed crystal phenomenon, and the overall performance, life and safety of train car shaft steel can be significantly improved. The product produced by the technology fully meets the relevant standard requirements, and the competitiveness of enterprises can be enhanced.
Description
Technical field
The present invention relates to refinement carbon axle grain fineness number production method, be specifically related to a kind of axle steel and production method thereof.
Background technology
Axletree is the vital part of vehicle to run part, subject deadweight and the load of vehicle, also withstand shocks in vehicle operating with when stopping power and damping force, one of three large vital parts (heavy rail, axletree and wheel) of railway construction, train shaft belongs to the stepped axial workpiece of ultra-large type rotational symmetry, its maximum diameter is about 200mm, and length reaches about 2200mm.
At present, the axletree material that China commonly uses is LZ50 steel, the axletree thermal treatment (" normalizing "+" secondary normalizing "+" tempering ") of producing with it afterwards grain fineness number only has 6.5 ~ 7.5 grades usually, and easily there is mixed crystal phenomenon (namely occurring the thick pearlite colony of part in tiny pearlitic structure), thus causing its intensity rank on the low side, extension property, plasticity are not enough.Along with the fast development of railway high speed, heavily loaded technology, in order to improve conveying efficiency, alleviate railway carriage weight, save transportation cost and extend railway carriage work-ing life, improve constantly the manufacture intensity rank of axles steel and the requirement of extension property, plasticity, fatigue property etc., this just has higher requirement to axletree material correlation technique.Therefore, the production method of a kind of refinement carbon axle of necessary exploitation grain fineness number, with crystal grain thinning, eliminates mixed crystal, improves the intensity rank of LZ50 axle steel, improve its extension property, plasticity index.
Summary of the invention
The object of the present invention is to provide a kind of axle steel and production method thereof, be specially a kind of production method of refinement carbon axle grain fineness number, designed by LZ50 axle steel optimizing components, axle blank rolling Technology Optimization, axle forging process optimization and axletree optimization of Heat Treatment Process etc., eliminate mixed crystal phenomenon with refinement LZ50 axletree grain fineness number, thus improve the intensity of train axle steel, extend, plasticity, fatigue resistance and low-temperature flexibility, and then significantly improve the overall performance of train axle steel, life-span and security, to meet China's track traffic at a high speed, the needs of heavy duty development.Concrete technical scheme is as follows:
A production method for axle steel, comprises the steps:
(1) axle forging;
(2) time processing;
(3) thermal treatment: a normalizing+secondary normalizing+tempering;
(4) secondary processing.
Further, step (3) specifically comprises the steps:
(3-1) normalizing: Heating temperature 950 ~ 980 DEG C, heating and thermal insulation, air-cooled or aerosol cooling;
(3-2) secondary normalizing: Heating temperature 790 ~ 820 DEG C, heating and thermal insulation, air-cooled or aerosol cooling;
(3-3) tempering: Heating temperature 520 ~ 560 DEG C, heating and thermal insulation, air cooling.
Further, in step (3), a normalizing 970 DEG C, heating and thermal insulation time 300min; Secondary normalizing 800 DEG C, heating and thermal insulation time 300min; Tempering 540 DEG C, heating and thermal insulation time 450min.
Further, step (2) comprising:
(2-1) blank axletree is rough turn;
(2-2) the neat end face processing of axletree.
Further, step (4) comprising:
Axletree outer circle finish turning is processed;
Axletree internal bore boring is processed.
Further, also comprise the steps:
(5) external grinding;
And/or,
(6) detect a flaw.
Further, soaking zone temperature 1230 ~ 1250 DEG C, this temperature section the residence time >=2 hours.
A kind of axle steel, adopts aforementioned production method to produce and obtains.
Further, containing, for example the component of lower weight proportion: 0.48-0.52%C, 0.19-0.34%Si, 0.64-0.86%Mn, 0.005-0.014%P, 0.001-0.006%S, 0.015-0.040%Nb, 0.018-0.035%Als, surplus is iron and inevitable impurity.
Further, its for maximum diameter be about 200mm, length reaches the Nb-microalloying LZ50 axle steel of about 2200mm, thermal treatment back axle be organized as perlite+ferrite, prior austenite grain size >=8.5 grade, without mixed crystal phenomenon.
Compared with currently available technology, the present invention is by adopting Nb-microalloying principle, in conjunction with to axle forging, optimization of Heat Treatment Process, the remarkable refinement grain fineness number of LZ50 axletree, thermal treatment back axle be organized as perlite+ferrite, prior austenite grain size >=8.5 grade, occur without mixed crystal phenomenon, thus significantly significantly improve the overall performance of train axle steel, life-span and security.The product that this technology is produced meets the requirement of relevant criterion completely, enhances the competitive power of enterprise.
Embodiment
Describe the present invention below, it is a kind of preferred embodiment in numerous embodiments of the present invention.
The LZ50 steel axletree technological process of production of the present invention is: axle forging → blank axletree is rough turn → and neat end face processing → " a normalizing+secondary normalizing+tempering " thermal treatment → axletree outer circle finish turning processing → axletree internal bore boring processing → external grinding → flaw detection of axletree.
In order to refinement LZ50 axletree crystal grain, eliminate mixed crystal, mainly take following technical scheme:
(1) optimization of Chemical Composition design, adopts Nb micro-alloying technology.Nb micro-alloying technology is adopted in LZ50 steel, the niobium carbonitrides formed because adding niobium on the one hand has pinning effect to crystal boundary, during heating, the effect suppressing Austenite Grain Growth can be played, the Coarsening Temperature of steel is made to improve about 100 DEG C, thus elevated heating processes can be adopted to alleviate component segregation when axle forging heats, excessive grain heat can being avoided to cause again is grown up; On the other hand, by the precipitation strength of its carbonitride, the intensity of steel also can be significantly improved.But it is expensive.Consider, the range-controllable of Nb is built in 0.015% ~ 0.040%.
(2) axle forging heating process is optimized.Common LZ50 is carbon steel, and during axle forging, high, the high temperature section residence time length of Heating temperature can cause excessive grain to be grown up, and finally by tissue heredity, causes final axletree grain coarsening, mixed crystal.After adopting Nb micro-alloying technology, because the grain coarsening temperature of LZ50 significantly improves, elevated heating processes (similar high temperature diffusion annealing) can be adopted, thus the abundant diffusion of the element such as C, Mn in steel can be ensured, reduce the segregation degree of the elements such as C, Mn, eliminate mixed crystal.Nb-microalloying LZ50 steel axle forging heating process is: soaking zone temperature 1230 ~ 1250 DEG C (common this temperature of LZ50 steel is generally no more than 1200 DEG C), this temperature section the residence time >=2 hours.
(3) axletree optimization of Heat Treatment Process.The mixed crystal of common LZ50 steel normally causes due to Structure Inheritance.Eliminate and weaken Structure Inheritance, one is use diffusion transformation recrystallization, at A
c3above, heat below phase transformation recrystallization temperature, utilize the new austenite of bulk generating and contact with original austenite No yield point to eliminate the Structure Inheritance in steel.Because this process always generates, so genetic elimination can not be thorough along with the new austenite of sheet having orientation to contact with original austenite; Two is utilize phase transformation recrystallize, and Heating temperature is selected in the above 30-50 DEG C of phase transformation recrystallization temperature, and during intensification heating, sample reaches A
c3temperature, first undergoes phase transition recrystallization, then reaches phase transformation recrystallization temperature, undergoes phase transition recrystallize. and the new crystal grain that phase transformation recrystallize is formed and the old crystal grain No yield point of original austenite contact, and do not have heredity.Because in fact the heating of phase transformation recrystallize has carried out once phase-change recrystallization and the transformation of once phase-change recrystallize, be the composite effect of two kinds of crystallizations, therefore splendid to the eradicating efficacy of tissue heredity.Because Nb microalloying significantly improves the AUSTENITE GRAIN COARSENING temperature of LZ50 steel, for high temperature normalizing creates condition.Nb-microalloying LZ50 steel axle forging heating process is:
1) normalizing: be about 200mm by maximum diameter, the length Nb-microalloying LZ50 axle steel that reaches about 2200mm is heated to temperature 950 ~ 980 DEG C, the heating and thermal insulation time calculates by 1.2 ~ 1.7min/mm, air-cooled or aerosol cooling.Not only refinement crystal grain after a normalizing, and improve the ununiformity of tissue, carry out tissue for finished heat treatment subsequently and prepare.
2) secondary normalizing: be about 200mm by maximum diameter, the length Nb-microalloying LZ50 axle steel that reaches about 2200mm is heated to temperature 790 ~ 820 DEG C, the heating and thermal insulation time calculates by 1.2 ~ 1.7min/mm, air-cooled or aerosol cooling.
3) tempering: be about 200mm by maximum diameter, length reach about 2200mm containing vanadium nitrogen carbon element train axle steel to Heating temperature 520 ~ 560 DEG C, the heating and thermal insulation time calculates by 2 ~ 2.5min/mm, and air cooling is to room temperature subsequently.Through tempering, even fine and closely woven perlite+ferritic metallographic structure can be obtained, prior austenite grain size >=8.0 grade, thus good toughness plasticity and suitable intensity index can be obtained.
In a preferred embodiment, the LZ50 steel axletree technological process of production is: axle forging → blank axletree is rough turn → and neat end face processing → " a normalizing+secondary normalizing+tempering " thermal treatment → axletree outer circle finish turning processing → axletree internal bore boring processing → external grinding → flaw detection of axletree.
The embodiment of the present invention's " normalizing+secondary normalizing+tempering " heat treated melting chemical composition, main heat treatment process parameter and performance is as follows:
Thermal treatment process step and parameter are:
(1) normalizing: Heating temperature 970 DEG C, heating and thermal insulation time 300min, air-cooled or aerosol cooling.
(2) secondary normalizing: Heating temperature 800 DEG C, heating and thermal insulation time 300min, air-cooled or aerosol cooling.
(3) tempering: Heating temperature 540 DEG C, heating and thermal insulation time 450min, air cooling.
The melting chemical composition mass percent (wt%) that maximum diameter is Φ 200mm, length reaches 2200mm train axle is in table 1, and the performance index of train axle after above thermal treatment are in table 2.
The melting chemical composition mass percent (wt%) of table 1LZ50 axles steel
Performance index after the thermal treatment of table 2LZ50 axletree
Adopt the LZ50 axletree that production method of the present invention is produced, thermal treatment back axle be organized as perlite+ferrite, prior austenite grain size >=8.5 grade, occur without mixed crystal phenomenon.
Above to invention has been exemplary description; obvious specific implementation of the present invention is not subject to the restrictions described above; as long as have employed method of the present invention design and the various improvement carried out of technical scheme, or directly apply to other occasion, all within protection scope of the present invention without improvement.
Claims (10)
1. a production method for axle steel, is characterized in that, comprises the steps:
(1) axle forging;
(2) time processing;
(3) thermal treatment: a normalizing+secondary normalizing+tempering;
(4) secondary processing.
2. the production method of axle steel as claimed in claim 1, it is characterized in that, step (3) specifically comprises the steps:
(3-1) normalizing: Heating temperature 950 ~ 980 DEG C, heating and thermal insulation, air-cooled or aerosol cooling;
(3-2) secondary normalizing: Heating temperature 790 ~ 820 DEG C, heating and thermal insulation, air-cooled or aerosol cooling;
(3-3) tempering: Heating temperature 520 ~ 560 DEG C, heating and thermal insulation, air cooling.
3. the production method of axle steel as claimed in claim 1 or 2, is characterized in that, in step (3), and a normalizing 970 DEG C, heating and thermal insulation time 300min; Secondary normalizing 800 DEG C, heating and thermal insulation time 300min; Tempering 540 DEG C, heating and thermal insulation time 450min.
4. the production method of the axle steel according to any one of claim 1-3, is characterized in that, step (2) comprising:
(2-1) blank axletree is rough turn;
(2-2) the neat end face processing of axletree.
5. the production method of the axle steel according to any one of claim 1-4, is characterized in that, step (4) comprising:
Axletree outer circle finish turning is processed;
Axletree internal bore boring is processed.
6. the production method of the axle steel according to any one of claim 1-5, is characterized in that, also comprises the steps:
(5) external grinding;
And/or,
(6) detect a flaw.
7. the production method of the axle steel according to any one of claim 1-6, is characterized in that, soaking zone temperature 1230 ~ 1250 DEG C, this temperature section the residence time >=2 hours.
8. an axle steel, is characterized in that, adopts production method as described in claim 1-7 to produce and obtains.
9. axle steel as claimed in claim 8, it is characterized in that, component containing, for example lower weight proportion: 0.48-0.52%C, 0.19-0.34%Si, 0.64-0.86%Mn, 0.005-0.014%P, 0.001-0.006%S, 0.015-0.040%Nb, 0.018-0.035%Als, surplus is iron and inevitable impurity.
10. axle steel as claimed in claim 8, it is characterized in that, its for maximum diameter be about 200mm, length reaches the Nb-microalloying LZ50 axle steel of about 2200mm, thermal treatment back axle be organized as perlite+ferrite, prior austenite grain size >=8.5 grade, without mixed crystal phenomenon.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201510231018.7A CN105132800A (en) | 2015-05-07 | 2015-05-07 | Car shaft steel and production method thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201510231018.7A CN105132800A (en) | 2015-05-07 | 2015-05-07 | Car shaft steel and production method thereof |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN105132800A true CN105132800A (en) | 2015-12-09 |
Family
ID=54718363
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201510231018.7A Pending CN105132800A (en) | 2015-05-07 | 2015-05-07 | Car shaft steel and production method thereof |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN105132800A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106498282A (en) * | 2016-10-27 | 2017-03-15 | 马钢(集团)控股有限公司 | A kind of micro-alloyed with Nb and Ti rolling stock axles steel |
| CN106854691A (en) * | 2016-10-31 | 2017-06-16 | 广东长盈精密技术有限公司 | Steel part Technology for Heating Processing, steel part forging method and annealing device using the Technology for Heating Processing |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103572032A (en) * | 2013-11-11 | 2014-02-12 | 南车长江车辆有限公司 | Thermal treatment process for wagon axle |
| CN104233109A (en) * | 2014-10-11 | 2014-12-24 | 马钢(集团)控股有限公司 | Heat-treating process of high-speed train axle containing niobium and titanium |
| CN104233110A (en) * | 2014-10-11 | 2014-12-24 | 马钢(集团)控股有限公司 | Steel for high-speed train axle containing niobium and titanium |
-
2015
- 2015-05-07 CN CN201510231018.7A patent/CN105132800A/en active Pending
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103572032A (en) * | 2013-11-11 | 2014-02-12 | 南车长江车辆有限公司 | Thermal treatment process for wagon axle |
| CN104233109A (en) * | 2014-10-11 | 2014-12-24 | 马钢(集团)控股有限公司 | Heat-treating process of high-speed train axle containing niobium and titanium |
| CN104233110A (en) * | 2014-10-11 | 2014-12-24 | 马钢(集团)控股有限公司 | Steel for high-speed train axle containing niobium and titanium |
Non-Patent Citations (1)
| Title |
|---|
| 杨家斌等: "《常用金属材料牌号手册》", 28 February 2009, 中国标准出版社 * |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106498282A (en) * | 2016-10-27 | 2017-03-15 | 马钢(集团)控股有限公司 | A kind of micro-alloyed with Nb and Ti rolling stock axles steel |
| CN106854691A (en) * | 2016-10-31 | 2017-06-16 | 广东长盈精密技术有限公司 | Steel part Technology for Heating Processing, steel part forging method and annealing device using the Technology for Heating Processing |
| CN106854691B (en) * | 2016-10-31 | 2019-04-05 | 广东长盈精密技术有限公司 | The forging method of steel part |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN104233109B (en) | Heat-treating process of high-speed train axle containing niobium and titanium | |
| EP3647453B1 (en) | Free machining and non-quenched and tempered steel and manufacturing method thereof | |
| CN101928878B (en) | Axle shaft steel and production method thereof | |
| US20210079491A1 (en) | Wire rod for cold heading, processed product using same, and manufacturing method therefor | |
| KR101685489B1 (en) | The Alloy Steel Which Is Used as The High Tough Outer Wheel of Constant Velocity Joint And The Method of The Same | |
| CN104264040B (en) | A kind of non-hardened and tempered steel and manufacture method thereof and use the bent axle that this non-hardened and tempered steel manufactures | |
| CN104372155B (en) | A kind of Technology for Heating Processing of the axletree of bullet train containing niobium | |
| CN106521343A (en) | Ultrahigh strength aluminum alloyed superhigh carbon wheel steel and heat treatment method thereof | |
| CN104233108A (en) | Heat-treating process of high-speed train axle containing niobium and titanium | |
| CN104233107A (en) | Steel for high-speed train axle containing niobium and titanium | |
| CN105132800A (en) | Car shaft steel and production method thereof | |
| CN110055470B (en) | Container corner fitting and heat treatment process thereof | |
| JPH11302727A (en) | Production of high strength shaft | |
| CN103352173A (en) | Preheat treatment method for 18CrNiMo7-6 alloy steel forged pieces | |
| CN110257727A (en) | A kind of preparation method of middle carbon high rigidity heavy-duty wheel steel and its heat treatment method and heavy-duty wheel | |
| CN100374603C (en) | Hot forged non-heat treated steel for induction hardening | |
| CN105603328A (en) | Torsion shaft steel | |
| CN104831162A (en) | Vanadium-nitrogen micro-alloyed carbon steel, heat treatment technology thereof, production method, and applications | |
| WO2013018893A1 (en) | Untempered steel for hot casting, hot-casted untempered article and method for producing same | |
| CN104213015B (en) | A kind of production method of DP steel, its purposes, roller washing machine and automobile | |
| CN104087846B (en) | A kind of high-carbon silicon boron shellfish wearable cast steel difficult to understand and preparation method thereof | |
| CN102747288B (en) | Component formula and heat treatment method of motor shaft material used in high-speed railway vehicles | |
| JPH10265891A (en) | Ferrite/pearlite type non-heat treated steel | |
| EP2806040B1 (en) | A martensitic alloy component and process of forming a martensitic alloy component | |
| CN114959502B (en) | Nb microalloyed fine-grain high-torque output gear steel, manufacturing method thereof and processing technology for producing gears |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| RJ01 | Rejection of invention patent application after publication |
Application publication date: 20151209 |