CN115710621A - Process method for reducing graphitization of carbon steel - Google Patents
Process method for reducing graphitization of carbon steel Download PDFInfo
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- CN115710621A CN115710621A CN202211299596.0A CN202211299596A CN115710621A CN 115710621 A CN115710621 A CN 115710621A CN 202211299596 A CN202211299596 A CN 202211299596A CN 115710621 A CN115710621 A CN 115710621A
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- 238000000034 method Methods 0.000 title claims abstract description 69
- 229910000975 Carbon steel Inorganic materials 0.000 title claims abstract description 60
- 239000010962 carbon steel Substances 0.000 title claims abstract description 59
- 238000005087 graphitization Methods 0.000 title claims abstract description 58
- 229910000831 Steel Inorganic materials 0.000 claims abstract description 51
- 239000010959 steel Substances 0.000 claims abstract description 51
- 238000001816 cooling Methods 0.000 claims abstract description 35
- 238000005096 rolling process Methods 0.000 claims abstract description 24
- 238000010438 heat treatment Methods 0.000 claims abstract description 3
- 238000004321 preservation Methods 0.000 claims abstract 3
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 13
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 abstract description 43
- 229910002804 graphite Inorganic materials 0.000 abstract description 36
- 239000010439 graphite Substances 0.000 abstract description 36
- 229910000677 High-carbon steel Inorganic materials 0.000 abstract description 9
- 229910052799 carbon Inorganic materials 0.000 abstract description 7
- 229910001562 pearlite Inorganic materials 0.000 abstract description 6
- 229910001566 austenite Inorganic materials 0.000 abstract description 5
- 229910000954 Medium-carbon steel Inorganic materials 0.000 abstract description 3
- 229910045601 alloy Inorganic materials 0.000 abstract description 3
- 239000000956 alloy Substances 0.000 abstract description 3
- VYZAMTAEIAYCRO-UHFFFAOYSA-N Chromium Chemical compound [Cr] VYZAMTAEIAYCRO-UHFFFAOYSA-N 0.000 abstract description 2
- RTAQQCXQSZGOHL-UHFFFAOYSA-N Titanium Chemical compound [Ti] RTAQQCXQSZGOHL-UHFFFAOYSA-N 0.000 abstract description 2
- 229910052804 chromium Inorganic materials 0.000 abstract description 2
- 239000011651 chromium Substances 0.000 abstract description 2
- 238000009792 diffusion process Methods 0.000 abstract description 2
- 229910052758 niobium Inorganic materials 0.000 abstract description 2
- 239000010955 niobium Substances 0.000 abstract description 2
- GUCVJGMIXFAOAE-UHFFFAOYSA-N niobium atom Chemical compound [Nb] GUCVJGMIXFAOAE-UHFFFAOYSA-N 0.000 abstract description 2
- 238000001953 recrystallisation Methods 0.000 abstract description 2
- 239000010936 titanium Substances 0.000 abstract description 2
- 229910052719 titanium Inorganic materials 0.000 abstract description 2
- 230000004931 aggregating effect Effects 0.000 abstract 1
- 238000005242 forging Methods 0.000 description 9
- 102200126521 rs4498440 Human genes 0.000 description 7
- 238000011946 reduction process Methods 0.000 description 4
- 239000000463 material Substances 0.000 description 2
- 239000000047 product Substances 0.000 description 2
- PZASAAIJIFDWSB-CKPDSHCKSA-N 8-[(1S)-1-[8-(trifluoromethyl)-7-[4-(trifluoromethyl)cyclohexyl]oxynaphthalen-2-yl]ethyl]-8-azabicyclo[3.2.1]octane-3-carboxylic acid Chemical compound FC(F)(F)C=1C2=CC([C@@H](N3C4CCC3CC(C4)C(O)=O)C)=CC=C2C=CC=1OC1CCC(C(F)(F)F)CC1 PZASAAIJIFDWSB-CKPDSHCKSA-N 0.000 description 1
- 229910000915 Free machining steel Inorganic materials 0.000 description 1
- 229910001567 cementite Inorganic materials 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- KSOKAHYVTMZFBJ-UHFFFAOYSA-N iron;methane Chemical compound C.[Fe].[Fe].[Fe] KSOKAHYVTMZFBJ-UHFFFAOYSA-N 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 239000002244 precipitate Substances 0.000 description 1
- 239000002436 steel type Substances 0.000 description 1
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Abstract
The invention provides a process method for reducing graphitization of carbon steel, which comprises the following steps: heating carbon steel to 1000 ℃ for austenitizing and heat preservation, and then carrying out controlled rolling and controlled cooling process to reduce the existing graphitization degree of the carbon steel. The invention rolls in the high carbon steel austenite non-recrystallization region through a controlled rolling and controlled cooling process, increases the deformation zone in the deformation austenite grains, forms fine lamellar pearlite or annealed pearlite, and reduces the diffusion distance of carbon so as to prevent the carbon from aggregating to form graphite. The high-carbon steel can generate gas expansion after graphitization, the product is easy to crack, at present, alloy elements such as chromium, titanium, niobium and the like are usually added into steel to prevent graphitization, and the price is high; the process method has the advantages of simple operation, low treatment temperature and low application cost, and can treat common medium and high carbon steel with the graphitization problem.
Description
Technical Field
The patent relates to the technical field of carbon steel treatment, in particular to a process method for reducing graphitization of carbon steel.
Background
In actual production, the carbon element in the microstructure of carbon steel does not generally appear in the form of graphite, but pearlite or cementite (Fe) 3 C) The state exists, but under certain conditions (such as cast state or after forging), the state of graphite may be decomposed, and the phenomenon is also called graphitization and is obvious in high carbon steel. Graphitized carbon steel has great brittleness, and the fracture is gray black, so the material is called as black and brittle, and the material fails. In order to obtain good performance, the occurrence of graphitization should be avoided. At present, the technology for eliminating the carbon steel graphitization of the product is rarely reported. Patent application 202010623648.X discloses a method for preparing a plate with anti-graphitization property to adapt to electrolytic environment, but the process method is complex, and the plate can achieve the anti-graphitization purpose only by the aid of trace alloy elements, so that the problem of treatment after graphitization of common medium and high carbon steel cannot be solved.
Disclosure of Invention
The invention aims to provide a process method for reducing graphitization of carbon steel, which selects proper rolling and cooling control process parameters to reduce the graphitization structure of the carbon steel and obtain a normal structure with homogenized components, so that the carbon steel can be used under normal working conditions.
In order to solve the technical problems, the invention adopts the following technical scheme:
a process method for reducing graphitization of carbon steel comprises the following steps:
the carbon steel is heated to 1000 plus or minus 10 ℃ (error value) to be austenitized, and then the controlled rolling and controlled cooling process is carried out to reduce the existing graphitization degree of the carbon steel.
The process for reducing graphitization of carbon steel according to claim 1, wherein the heating and holding time is as follows: t = CB
In the formula: t-time h; b, the thickness of the blank is cm; c is the steel type coefficient, and the carbon steel is 0.1-0.15.
The process method for reducing the graphitization of carbon steel according to claim 1, wherein the controlled rolling and controlled cooling process comprises the following rolling processes: rolling at the following temperatures: 750-900 ℃; the thickness reduction rate of rolled carbon steel is 55-60%.
The rolling temperature of the process method for reducing the graphitization of the carbon steel is 850 ℃.
The cooling process of the controlled rolling and cooling process for reducing the graphitization of the carbon steel comprises the following steps: and (4) taking out the rolled carbon steel, and putting the rolled carbon steel into water to cool to room temperature.
The cooling process of the controlled rolling and cooling process for reducing the graphitization of the carbon steel comprises the following steps: and taking out the rolled carbon steel, and cooling the rolled carbon steel to room temperature in the air.
The process method can be used for graphitizing various medium and high carbon steels, has good effect of eliminating graphitization within the range of 1-5% of the graphite content of T12 steel, and particularly is used for carbon steel with the common graphite content of about 2.5%.
Compared with the prior art, the invention has the advantages that:
the invention provides a process method for reducing graphitization of carbon steel, which selects proper controlled rolling and controlled cooling process parameters to reduce graphitization structure of T12 steel (high-carbon steel) and obtain normal structure with homogenized components, so that 'black and crisp' is eliminated. The prior art aims to improve the graphitization rate of carbon steel, so that the free-cutting steel has good forming performance. The invention increases the deformation zone in the deformed austenite grains by rolling in the high-carbon steel austenite non-recrystallization region and adding larger pass deformation through a controlled rolling and controlled cooling process. As described above, the carbide precipitates not only at the austenite grain boundaries but also at the deformed band regions in the grains, and is dispersed to form fine lamellar pearlite or annealed pearlite (also referred to as metamorphic pearlite), the microstructure is further improved, the diffusion distance of carbon is reduced, and carbon is not aggregated to form graphite, and therefore the existing form of carbon is contrary to the existing state of carbon after graphitization. The high-carbon steel can generate gas expansion after graphitization, the product is easy to crack, at present, alloy elements such as chromium, titanium, niobium and the like are usually added into steel to prevent graphitization, and the price is high; the process method has the advantages of simple operation, low treatment temperature and low application cost, and can treat common medium and high carbon steel with the graphitization problem.
Drawings
FIG. 1 shows a polished microstructure (100 times) of T12A steel which is not treated by the graphitization reduction method of the invention after forging, and the graphite content is 2.48%;
FIG. 2 is a microstructure (200 times) of forged T12A steel treated by the graphitization reduction process of the present invention, wherein (a) is water cooling; (b) air cooling;
FIG. 3 is a microstructure (200 times) of forged T12A steel after rolling at 900 ℃ by the graphitization reduction process of the present invention, wherein (a) is water cooling; (b) air cooling;
FIG. 4 is a microstructure (200 times) of forged T12A steel rolled at 800 ℃ by the graphitization reduction process of the present invention, wherein (a) is water cooling; (b) air cooling;
FIG. 5 is a microstructure (200 times) of forged T12A steel after rolling at 750 ℃ by the graphitization reduction process of the present invention, in which (a) is water cooling; (b) air cooling;
FIG. 6 shows that the graphitization of the T12A steel is reduced by the process method of the invention when the T12A steel is in a forged state: the graphite contents obtained by different cooling methods after rolling and matching at different temperatures.
Detailed Description
Example 1 a process for reducing graphitization of carbon steel:
the graphite content of the T12 steel is 2.48 percent, the thickness of a forging state sample is 10mm, the sample is austenitized at 1000 ℃, the temperature is kept for 0.12h, and the sample is rolled to be 4 +/-0.5 mm thick at 850 ℃; then the steel is put into water to be cooled to room temperature, and the graphite content of the obtained steel is 0.2 percent.
Embodiment 2a process for reducing graphitization of carbon steel:
the graphite content of the T12 steel is 2.48 percent, the thickness of a forged sample is 10mm, the sample is austenitized at 1000 ℃, the temperature is kept for 0.12h, and the sample is rolled to be 4 +/-0.5 mm thick at 850 ℃; then cooling the steel to room temperature in the air, wherein the graphite content of the obtained steel is 0.85 percent.
Embodiment 3 a process for reducing graphitization of carbon steel:
the graphite content of the T12 steel is 2.48 percent, the thickness of a forged sample is 10mm, the sample is austenitized at 1000 ℃, the temperature is kept for 0.12h, and the sample is rolled to be 4.3 +/-0.5 mm thick at 750 ℃; then the steel is put into water to be cooled to room temperature, and the graphite content of the obtained steel is 0.3 percent.
Embodiment 4 a process for reducing graphitization of carbon steel:
the graphite content of the T12 steel is 2.48 percent, the thickness of a forged sample is 10mm, the sample is austenitized at 1000 ℃, the temperature is kept for 0.12h, and the sample is rolled to be 4.3 +/-0.5 mm thick at 750 ℃; then cooling the steel to room temperature in the air, wherein the graphite content of the obtained steel is 0.97%.
Example 5 a process for reducing graphitization of carbon steel:
the graphite content of the T12 steel is 2.48 percent, the thickness of a forging state sample is 10mm, the sample is austenitized at 1000 ℃, the temperature is kept for 0.12h, and the sample is rolled to be 4 +/-0.5 mm thick at 800 ℃; then the steel is put into water to be cooled to room temperature, and the graphite content of the obtained steel is 0.55 percent.
Example 6 a process for reducing graphitization of carbon steel:
the graphite content of the T12 steel is 2.48 percent, the thickness of a forging state sample is 10mm, the sample is austenitized at 1000 ℃, the temperature is kept for 0.12h, and the sample is rolled to be 4 +/-0.5 mm thick at 800 ℃; then cooling the steel to room temperature in the air, wherein the graphite content of the obtained steel is 0.79 percent.
Example 7 a process for reducing graphitization of carbon steel:
the graphite content of the T12 steel is 2.48 percent, the thickness of a forged sample is 10mm, the sample is austenitized at 1000 ℃, the temperature is kept for 0.12h, and the sample is rolled at 900 ℃ to be 4.5 +/-0.5 mm thick; then the steel is put into water to be cooled to room temperature, and the graphite content of the obtained steel is 0.58%.
Embodiment 8 a process for reducing graphitization of carbon steel:
the graphite content of the T12 steel is 2.48 percent, the thickness of a forging state sample is 10mm, the sample is austenitized at 1000 ℃, the temperature is kept for 0.12h, and the sample is rolled to be 4.5 +/-0.5 mm thick at 900 ℃; then cooling to room temperature in the air, and the graphite content of the obtained steel is 0.91%.
Example 9 a process for reducing graphitization of carbon steel:
the graphite content of the T12 steel is 1.03 percent, the thickness of a forging state sample is 10mm, the sample is austenitized at 1000 ℃, the temperature is kept for 0.12h, and the sample is rolled to be 4 +/-0.5 mm thick at 850 ℃; then the steel is put into water to be cooled to room temperature, and the graphite content of the obtained steel is 0.06%.
Example 10 a process for reducing graphitization of carbon steel:
the graphite content of the T12 steel is 1.03 percent, the thickness of a forged sample is 10mm, the sample is austenitized at 1000 ℃, the temperature is kept for 0.12h, and the sample is rolled to be 4 +/-0.5 mm thick at 850 ℃; then cooling the steel to room temperature in the air, wherein the graphite content of the obtained steel is 0.10%.
Example 11 a process for reducing graphitization of carbon steel:
the graphite content of the T12 steel is 4.36 percent, the thickness of a forged sample is 10mm, the sample is austenitized at 1000 ℃, the temperature is kept for 0.12h, and the sample is rolled at 850 ℃ to be 4.7 +/-0.5 mm thick; then the steel is put into water to be cooled to room temperature, and the graphite content of the obtained steel is 0.45 percent.
Example 12a process for reducing graphitization of carbon steel:
the graphite content of the T12 steel is 4.36 percent, the thickness of a forged sample is 10mm, the sample is austenitized at 1000 ℃, the temperature is kept for 0.12h, and the sample is rolled to be 4.7 +/-0.5 mm thick at 850 ℃; then cooling to room temperature in the air, and the graphite content of the obtained steel is 0.90%.
Example 13 a process for reducing graphitization of carbon steel:
the graphite content of the T12 steel is 3.77%, the thickness of a forging state sample is 10mm, the sample is austenitized at 1000 ℃, the temperature is kept for 0.12h, and the sample is rolled at 750 ℃ to be 4 +/-0.5 mm thick; then the steel is put into water to be cooled to room temperature, and the graphite content of the obtained steel is 0.50 percent.
Example 14 a process for reducing graphitization of carbon steel:
the graphite content of the T12 steel is 3.77%, the thickness of a forging state sample is 10mm, the sample is austenitized at 1000 ℃, the temperature is kept for 0.12h, and the sample is rolled to be 4 +/-0.5 mm thick at 750 ℃; then cooling to room temperature in the air, and the graphite content of the obtained steel is 0.99%.
Claims (6)
1. A process method for reducing graphitization of carbon steel is characterized by comprising the following steps:
the carbon steel is heated to 1000 ℃ for austenitizing and heat preservation, and then a controlled rolling and controlled cooling process is carried out to reduce the existing graphitization degree of the carbon steel.
2. A process for reducing graphitization of carbon steel according to claim 1 wherein: the heating and heat preservation time is as follows:
T＝CB
in the formula: t-time h; b, the thickness of the blank is cm; c is the steel grade coefficient, and the carbon steel is 0.1-0.15.
3. A process for reducing graphitization of carbon steel according to claim 1 wherein: the rolling process of the controlled rolling and controlled cooling process comprises the following steps: rolling at the following temperatures: 750-900 ℃; the thickness reduction rate of rolled carbon steel is 55-60%.
4. A process for reducing graphitization of carbon steel according to claim 3 wherein: the rolling temperature was 850 ℃.
5. A process for reducing graphitization of carbon steel according to claim 1 wherein: the cooling process of the controlled rolling and controlled cooling process comprises the following steps: and taking out the carbon steel after rolling, and putting the carbon steel into water to cool the carbon steel to room temperature.
6. A process for reducing graphitization of carbon steel according to claim 1 wherein: the cooling process of the controlled rolling and controlled cooling process comprises the following steps: and taking out the rolled carbon steel, and cooling the rolled carbon steel to room temperature in the air.
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Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH07102319A (en) * | 1993-10-04 | 1995-04-18 | Nippon Steel Corp | Production of graphitic steel |
| JPH0860296A (en) * | 1994-08-24 | 1996-03-05 | Nippon Steel Corp | Fine graphite uniformly dispersed bar steel excellent in toughness and its production |
| US6174384B1 (en) * | 1998-10-15 | 2001-01-16 | Agency Of Industrial Science And Technology | Medium-carbon steel having dispersed fine graphite structure and method for the manufacture thereof |
| CN1854324A (en) * | 2005-04-29 | 2006-11-01 | 宝山钢铁股份有限公司 | Production of high-alloy cold mould steel |
| JP2010144242A (en) * | 2008-12-22 | 2010-07-01 | Nippon Steel Corp | Medium and high carbon steel plate and manufacturing method of the same |
| CN106834962A (en) * | 2017-03-29 | 2017-06-13 | 沈阳工业大学 | A kind of strong high-carbon low-alloy steel of superelevation and its shaping and heat-treatment technology method |
| CN109735773A (en) * | 2018-12-28 | 2019-05-10 | 首钢集团有限公司 | A kind of high-carbon steel pearlite lamella interval controlling method |
| CN110016541A (en) * | 2019-05-24 | 2019-07-16 | 东北大学 | A method of the GCr15 bearing ball annealing time is shortened by cooling controlling and rolling controlling process |
-
2022
- 2022-10-23 CN CN202211299596.0A patent/CN115710621A/en active Pending
Patent Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH07102319A (en) * | 1993-10-04 | 1995-04-18 | Nippon Steel Corp | Production of graphitic steel |
| JPH0860296A (en) * | 1994-08-24 | 1996-03-05 | Nippon Steel Corp | Fine graphite uniformly dispersed bar steel excellent in toughness and its production |
| US6174384B1 (en) * | 1998-10-15 | 2001-01-16 | Agency Of Industrial Science And Technology | Medium-carbon steel having dispersed fine graphite structure and method for the manufacture thereof |
| CN1854324A (en) * | 2005-04-29 | 2006-11-01 | 宝山钢铁股份有限公司 | Production of high-alloy cold mould steel |
| JP2010144242A (en) * | 2008-12-22 | 2010-07-01 | Nippon Steel Corp | Medium and high carbon steel plate and manufacturing method of the same |
| CN106834962A (en) * | 2017-03-29 | 2017-06-13 | 沈阳工业大学 | A kind of strong high-carbon low-alloy steel of superelevation and its shaping and heat-treatment technology method |
| CN109735773A (en) * | 2018-12-28 | 2019-05-10 | 首钢集团有限公司 | A kind of high-carbon steel pearlite lamella interval controlling method |
| CN110016541A (en) * | 2019-05-24 | 2019-07-16 | 东北大学 | A method of the GCr15 bearing ball annealing time is shortened by cooling controlling and rolling controlling process |
Non-Patent Citations (2)
| Title |
|---|
| 何忠治等: "碳素工具钢中渗碳体石墨化的研究", 金属学报, vol. 1, no. 3, 31 March 1956 (1956-03-31), pages 279 - 286 * |
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