CN101921960A - Microalloyed steel and production method thereof - Google Patents
Microalloyed steel and production method thereof Download PDFInfo
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- CN101921960A CN101921960A CN 201010258683 CN201010258683A CN101921960A CN 101921960 A CN101921960 A CN 101921960A CN 201010258683 CN201010258683 CN 201010258683 CN 201010258683 A CN201010258683 A CN 201010258683A CN 101921960 A CN101921960 A CN 101921960A
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- alloyed steel
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- 229910000742 Microalloyed steel Inorganic materials 0.000 title claims abstract description 46
- 238000004519 manufacturing process Methods 0.000 title claims abstract description 17
- 229910000831 Steel Inorganic materials 0.000 claims abstract description 69
- 239000010959 steel Substances 0.000 claims abstract description 69
- 239000000126 substance Substances 0.000 claims abstract description 17
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 claims abstract description 16
- 239000012535 impurity Substances 0.000 claims abstract description 10
- 229910052799 carbon Inorganic materials 0.000 claims abstract description 8
- 229910052742 iron Inorganic materials 0.000 claims abstract description 8
- 239000004615 ingredient Substances 0.000 claims description 16
- 238000000034 method Methods 0.000 claims description 14
- 238000001816 cooling Methods 0.000 claims description 11
- 238000005096 rolling process Methods 0.000 claims description 11
- 229910052720 vanadium Inorganic materials 0.000 claims description 8
- 229910052782 aluminium Inorganic materials 0.000 claims description 7
- 238000009413 insulation Methods 0.000 claims description 7
- 238000013021 overheating Methods 0.000 claims description 3
- 230000007797 corrosion Effects 0.000 abstract description 21
- 238000005260 corrosion Methods 0.000 abstract description 21
- 150000003839 salts Chemical class 0.000 abstract description 16
- 239000007921 spray Substances 0.000 abstract description 11
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 abstract description 2
- 229910045601 alloy Inorganic materials 0.000 abstract 1
- 239000000956 alloy Substances 0.000 abstract 1
- 239000000203 mixture Substances 0.000 abstract 1
- 238000005275 alloying Methods 0.000 description 3
- 238000011161 development Methods 0.000 description 3
- 230000000694 effects Effects 0.000 description 3
- 238000012360 testing method Methods 0.000 description 3
- FAPWRFPIFSIZLT-UHFFFAOYSA-M Sodium chloride Chemical compound [Na+].[Cl-] FAPWRFPIFSIZLT-UHFFFAOYSA-M 0.000 description 2
- 239000013078 crystal Substances 0.000 description 2
- 230000002349 favourable effect Effects 0.000 description 2
- 239000003595 mist Substances 0.000 description 2
- 238000010998 test method Methods 0.000 description 2
- LEONUFNNVUYDNQ-UHFFFAOYSA-N vanadium atom Chemical compound [V] LEONUFNNVUYDNQ-UHFFFAOYSA-N 0.000 description 2
- 230000003245 working effect Effects 0.000 description 2
- 229910000851 Alloy steel Inorganic materials 0.000 description 1
- 238000003723 Smelting Methods 0.000 description 1
- 239000004411 aluminium Substances 0.000 description 1
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 1
- 230000006378 damage Effects 0.000 description 1
- 238000013016 damping Methods 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 230000006698 induction Effects 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 238000005272 metallurgy Methods 0.000 description 1
- 230000007935 neutral effect Effects 0.000 description 1
- 238000001556 precipitation Methods 0.000 description 1
- 238000002360 preparation method Methods 0.000 description 1
- 230000035939 shock Effects 0.000 description 1
- 239000011780 sodium chloride Substances 0.000 description 1
- 238000005507 spraying Methods 0.000 description 1
- 238000010561 standard procedure Methods 0.000 description 1
- 238000005728 strengthening Methods 0.000 description 1
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- Heat Treatment Of Steel (AREA)
Abstract
The invention relates to microalloyed steel and a production method thereof, belonging to the field of alloy. The invention needs to solve the technical problem of providing microalloyed steel with better salt spray corrosion resistance. The microalloyed steel comprises the following chemical compositions in percentage by weight: 0.30-0.46% of C, 0.30-0.50% of Si, 0.40-0.90% of Mn, 0.07-0.20% of V, 0.31-1.00% of Cr and the balance of iron and inevitable impurities. Compared with the traditional carbon axle steel, the microalloyed steel has better salt spray corrosion resistance and impact toughness and can meet the requirements of high performance axle steel especially axle steel for rail wagons. The invention provides a new selection for the axle steel for rail wagons and has broad application prospect.
Description
Technical field
The present invention relates to micro-alloyed steel and production method thereof, belong to field of metallurgy.
Background technology
Axletree is the vitals of rail truck running part, they are bearing all wts of vehicle, when train operation and parking, the effect of power and the damping force of also will experiencing a shock, under the state of high speed and heavy duty, stressing conditions is just more complicated, and its quality state is directly connected to safety of railway traffic.For the consideration on the safety, railroad car axle there is strict technical requirements: such as, require to have enough intensity and impelling strength, to guarantee under top speed and ultimate load condition, to be perfectly safe reliably; Good wear resistance is arranged, to guarantee work-ing life; Under enough intensity and certain life-span prerequisite, alleviate its weight, alleviate unsprung weight as much as possible and keep certain flexibility.
China is from the foundation initial stage, and rail truck is continued to use LZ40 steel axletree always, because this steel axle fatigue strength is low, work-ing life is short, and the axle press-fitting position is prone to transverse crack, and it is high-speed to adapt to present train, the demand for development of large conveying quantity.In order to satisfy the needs of China railways fast development, the Ministry of Railways had issued China railways car axle-steel standard (TB/T2945-1999) in 1999, and from then on China's Rolling Stock begins to adopt LZ50 steel axletree with axletree comprehensively, had progressively replaced LZ40 steel axletree in the past.But in recent years, fast development along with China Railway, the railway freight-car axle is heavy constantly to be increased, road speed improves constantly, demands for higher performance to lorry axle, no matter existing LZ50 axletree still be that aspect such as fatigue property can not satisfy service requirements in mechanical property, has the LZ50 axletree simultaneously now and does not possess corrosion resistance nature substantially, causes the destruction in advance of axletree under corrosive environment easily.
Application number is 200810171563.1, denomination of invention discloses a kind of axle steel for the Chinese patent application of " a kind of axle steel and preparation method thereof ", this steel has higher intensity, but its salt spray corrosion resistance and impelling strength are difficult to satisfy the requirement that the railcar axle-steel is got over Gao Yuegao.
Summary of the invention
Technical problem to be solved by this invention provides the better micro-alloyed steel of a kind of salt spray corrosion resistance.
Micro-alloyed steel of the present invention contains the chemical ingredients of following weight percent: 0.30%～0.46%C, 0.30%～0.50%Si, and 0.40%～0.90%Mn, 0.07%～0.20%V, 0.31%～1.00%Cr, surplus is iron and unavoidable impurities.
Wherein, as optimized technical scheme, the chemical ingredients of micro-alloyed steel of the present invention also contains 0.010%～0.060% Al by weight percentage.
Above-mentioned unavoidable impurities comprises P and S, wherein, by weight percentage, [P]≤0.020%, [S]≤0.015%.
The present invention also provides the method for producing micro-alloyed steel, this method comprises the production and the billet rolling step of steel billet, wherein, steel billet can get according to ordinary method production, and steel billet contains the chemical ingredients of following weight percent: 0.30%～0.46%C, 0.30%～0.50%Si, 0.40%～0.90%Mn, 0.07%～0.20%V, 0.31%～1.00%Cr, surplus is iron and unavoidable impurities; Described billet rolling step is: steel billet is heated to 1200～1250 ℃, begins rolling steel billet then after being incubated 2.0～2.5h under 1200～1250 ℃ of temperature, and the finishing temperature of steel billet is 850～950 ℃, rolls the back air cooling and promptly gets micro-alloyed steel.All the other steps are identical with conventional axle steel production method.Wherein, as optimized technical scheme, the chemical ingredients of above-mentioned steel billet also contains 0.010%～0.060% Al by weight percentage.
Further, better for the performance that makes the micro-alloyed steel that the inventive method produces, above-mentioned steel billet is swaged into after the required specification also through Overheating Treatment, and heat treating method is: 850～870 ℃ of insulation 30～60min, air cooling promptly gets micro-alloyed steel then.As optimized technical scheme, above-mentioned heat treating method is: 860 ℃ of insulation 45min, air cooling promptly gets micro-alloyed steel then.
Compare traditional carbon axle, micro-alloyed steel of the present invention has better salt spray corrosion resistance and impelling strength, can satisfy the particularly needs of lorry axle steel of high-performance axletree steel, the present invention has broad application prospects for the lorry axle steel provides a kind of new selection.
Description of drawings
Fig. 1 is micro-alloyed steel of the present invention and LZ50 axle steel, and the corrosion resistance nature comparison diagram of 30CrMo steel.
Embodiment
Micro-alloyed steel of the present invention contains the chemical ingredients of following weight percent: 0.30%～0.46%C, 0.30%～0.50%Si, and 0.40%～0.90%Mn, 0.07%～0.20%V, 0.31%～1.00%Cr, surplus is iron and unavoidable impurities.
Wherein, as optimized technical scheme, the chemical ingredients of micro-alloyed steel of the present invention also contains 0.010%～0.060% Al by weight percentage.
Above-mentioned unavoidable impurities comprises P and S, wherein, by weight percentage, [P]≤0.020%, [S]≤0.015%.
The yield strength R of micro-alloyed steel of the present invention
ELCan reach more than the 400MPa tensile strength R
mCan reach more than the 700MPa, can satisfy the requirement of axle steel fully strength property.Micro-alloyed steel of the present invention normal temperature U type impact and can reach more than the 65J, its toughness obviously is better than existing axle steel.And the resisting salt fog corrosion of micro-alloyed steel of the present invention can improve about 10% by force rate LZ50 axle steel.
Why micro-alloyed steel of the present invention has above-mentioned premium properties, mainly has been to add an amount of alloying element, as: add the alloying element vanadium, utilize the precipitation strength of vanadium and the effect of crystal grain thinning, can improve the intensity of steel, guarantee the plasticity and toughness of steel; Add the Cr element, can play certain solution strengthening effect, favourable to the corrosion resistance nature that improves steel simultaneously; Add Al, except playing the crystal grain of desoxydatoin, refinement steel, also favourable to the toughness of improving steel.Just because of the acting in conjunction of multiple alloying element, just make micro-alloyed steel of the present invention have excellent comprehensive performances.
The method that the present invention produces micro-alloyed steel comprises the production and the billet rolling step of steel billet, wherein, steel billet can get according to ordinary method production, steel billet contains the chemical ingredients of following weight percent: 0.30%～0.46%C, 0.30%～0.50%Si, 0.40%～0.90%Mn, 0.07%～0.20%V, 0.31%～1.00%Cr, surplus is iron and unavoidable impurities; Described billet rolling step is: steel billet is heated to 1200～1250 ℃, begins rolling steel billet then after being incubated 2.0～2.5h under 1200～1250 ℃ of temperature, and the finishing temperature of steel billet is 850～950 ℃, rolls the back air cooling and promptly gets micro-alloyed steel.All the other steps are identical with conventional axle steel production method.Wherein, as optimized technical scheme, the chemical ingredients of above-mentioned steel billet also contains 0.010%～0.060% Al by weight percentage.
Further, better for the performance that makes the micro-alloyed steel that the inventive method produces, above-mentioned steel billet is swaged into after the required specification also through Overheating Treatment, and heat treating method is: 850～870 ℃ of insulation 30～60min, air cooling promptly gets micro-alloyed steel then.As optimized technical scheme, above-mentioned heat treating method is: 860 ℃ of insulation 45min, air cooling promptly gets micro-alloyed steel then.
Below in conjunction with embodiment the specific embodiment of the present invention is further described, does not therefore limit the present invention among the described scope of embodiments.
The production of embodiment micro-alloyed steel of the present invention
1, produces steel billet
Press the chemical ingredients of table 1 and produce steel billet.Steel billet adopts the 50kg vacuum induction furnace smelting in the laboratory, cast forms then.
The chemical ingredients of table 1 steel billet (wt%, surplus is an iron)
Annotate: Als is the meaning of sour molten aluminium.
2, billet rolling
Steel billet is heated to 1200～1250 ℃, begins rolling steel billet then after being incubated 2.0～2.5h under 1200～1250 ℃ of temperature, and the finishing temperature of steel billet is 850～950 ℃, rolls the back air cooling; Described steel billet is swaged into after the required specification air cooling behind 860 ℃ of insulation 45min, promptly gets micro-alloyed steel (pole of φ 30mm).
Test routine micro-alloyed steel performance measurement
Measure yield strength, tensile strength, unit elongation, reduction of area, the normal temperature U type ballistic work of the micro-alloyed steel of the present invention of the foregoing description production respectively, the results are shown in Table 2,3.
Table 2 micro-alloyed steel tensile property of the present invention detected result
| Numbering | Yield strength R eL/MPa | Tensile strength R m/MPa | Unit elongation A/% | Reduction of area Z/% |
| A1 | ?443 | 720 | 27.0 | 59.5 |
| A2 | ?483 | 745 | 24.5 | 43.8 |
| A3 | ?490 | 750 | 25.5 | 60.5 |
Table 3 micro-alloyed steel normal temperature of the present invention U type ballistic work test-results
Adopt the salt spray corrosion resistance of salt spray corrosion test method test micro-alloyed steel of the present invention (used micro-alloyed steel of the present invention be numbered A2) and LZ50 axle steel, 30CrMo steel alloy, the result as shown in Figure 1.
The salt spray corrosion test method is: adopt the neutral salt spray test standard method of GB/T10125-1997, sample is placed FQY010 type salt-mist corrosion tester, with concentration is the NaCl solution intermittent type spraying of 50g/L, form salt mist environment, the weightlessness of utilizing metallic corrosion to produce is come measure sample corrosion rate within a certain period of time.In that section internal corrosion rate is high more sometime, illustrate that salt spray corrosion resistance is poor more; Otherwise salt spray corrosion resistance is good more.
As can be seen from Figure 1, in 72～240h salt air corrosion time range, the salt air corrosion rate of microalloy lorry axle steel of the present invention is better than the LZ50 axletree between 30CrMo and LZ50 axle steel, be lower than the 30CrMo steel.Compare with the LZ50 axle steel, microalloy lorry axle steel resisting salt fog corrosion of the present invention can improve about 10% by force rate LZ50 axletree.The chemical ingredients of 30CrMo and LZ50 axle steel is as shown in table 4.
The chemical ingredients of table 430CrMo and LZ50 axle steel
| C | Si | Mn | Cr | Als | ||
| The LZ50 steel | 0.47 | 0.30 | 0.83 | 0.238 | V：0.032 | 0.033 |
| 30CrMo | 0.31 | 0.34 | 0.62 | 0.960 | Mo：0.200 | 0.355 |
Claims (7)
1. micro-alloyed steel is characterized in that it contains the chemical ingredients of following weight percent: 0.30%～0.46%C, 0.30%～0.50%Si, 0.40%～0.90%Mn, 0.07%～0.20%V, 0.31%～1.00%Cr, surplus is iron and unavoidable impurities.
2. micro-alloyed steel according to claim 1 is characterized in that: its chemical ingredients also contains 0.010%～0.060% Al by weight percentage.
3. micro-alloyed steel according to claim 1 and 2 is characterized in that: described unavoidable impurities comprises P and S, wherein, by weight percentage, [P]≤0.020%, [S]≤0.015%.
4. produce the method for micro-alloyed steel, the production and the billet rolling step that comprise steel billet, it is characterized in that: described steel billet contains the chemical ingredients of following weight percent: 0.30%～0.46%C, 0.30%～0.50%Si, 0.40%～0.90%Mn, 0.07%～0.20%V, 0.31%～1.00%Cr, surplus is iron and unavoidable impurities; Described billet rolling step is: steel billet is heated to 1200～1250 ℃, begins rolling steel billet then after being incubated 2.0～2.5h under 1200～1250 ℃ of temperature, and the finishing temperature of steel billet is 850～950 ℃, forges the back air cooling and promptly gets micro-alloyed steel.
5. the method for production micro-alloyed steel according to claim 4 is characterized in that: the chemical ingredients of described steel billet also contains 0.010%～0.060% Al by weight percentage.
6. according to the method for claim 4 or 5 described production micro-alloyed steels, it is characterized in that: described steel billet is swaged into after the required specification also through Overheating Treatment, and heat treating method is: 850～870 ℃ of insulation 30～60min, air cooling promptly gets micro-alloyed steel then.
7. the method for production micro-alloyed steel according to claim 6 is characterized in that: described heat treating method is: 860 ℃ of insulation 45min, air cooling promptly gets micro-alloyed steel then.
Priority Applications (1)
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| CN 201010258683 CN101921960A (en) | 2010-08-20 | 2010-08-20 | Microalloyed steel and production method thereof |
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| Application Number | Priority Date | Filing Date | Title |
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| CN 201010258683 CN101921960A (en) | 2010-08-20 | 2010-08-20 | Microalloyed steel and production method thereof |
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Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102644033A (en) * | 2012-04-17 | 2012-08-22 | 中国铁道科学研究院金属及化学研究所 | Axle steel used for railway vehicle and preparation method for axle steel |
| CN102719749A (en) * | 2012-06-28 | 2012-10-10 | 宝山钢铁股份有限公司 | Steel for railway axle and production process for steel |
| CN102876982A (en) * | 2011-07-14 | 2013-01-16 | 宝山钢铁股份有限公司 | Axle steel and its manufacturing method |
| CN103320698A (en) * | 2013-06-18 | 2013-09-25 | 山西太钢不锈钢股份有限公司 | Axle steel and preparation method thereof |
| CN103975080A (en) * | 2011-10-07 | 2014-08-06 | 巴巴萨海布·尼尔康德·卡利亚尼 | A process to improve fatigue strength of micro alloy steels, forged parts made from the process and an apparatus to execute the process |
| CN107964625A (en) * | 2017-11-09 | 2018-04-27 | 石家庄钢铁有限责任公司 | A kind of big specification pallet fork round steel of low-temperature impact-resistant toughness and its production method |
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2010
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| CN101724787A (en) * | 2008-10-21 | 2010-06-09 | 攀钢集团研究院有限公司 | Axle shaft steel and preparation method thereof |
| CN101497969A (en) * | 2009-03-13 | 2009-08-05 | 武汉钢铁(集团)公司 | High-performance weather-resisting anti-seismic steel for building and production method thereof |
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Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102876982A (en) * | 2011-07-14 | 2013-01-16 | 宝山钢铁股份有限公司 | Axle steel and its manufacturing method |
| CN103975080A (en) * | 2011-10-07 | 2014-08-06 | 巴巴萨海布·尼尔康德·卡利亚尼 | A process to improve fatigue strength of micro alloy steels, forged parts made from the process and an apparatus to execute the process |
| CN102644033A (en) * | 2012-04-17 | 2012-08-22 | 中国铁道科学研究院金属及化学研究所 | Axle steel used for railway vehicle and preparation method for axle steel |
| CN102719749A (en) * | 2012-06-28 | 2012-10-10 | 宝山钢铁股份有限公司 | Steel for railway axle and production process for steel |
| CN103320698A (en) * | 2013-06-18 | 2013-09-25 | 山西太钢不锈钢股份有限公司 | Axle steel and preparation method thereof |
| CN107964625A (en) * | 2017-11-09 | 2018-04-27 | 石家庄钢铁有限责任公司 | A kind of big specification pallet fork round steel of low-temperature impact-resistant toughness and its production method |
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Application publication date: 20101222 |