CN114888079A - Rolling process of 38CrMoAl round steel - Google Patents
Rolling process of 38CrMoAl round steel Download PDFInfo
- Publication number
- CN114888079A CN114888079A CN202210510947.1A CN202210510947A CN114888079A CN 114888079 A CN114888079 A CN 114888079A CN 202210510947 A CN202210510947 A CN 202210510947A CN 114888079 A CN114888079 A CN 114888079A
- Authority
- CN
- China
- Prior art keywords
- rolling
- equal
- round steel
- temperature
- 38crmoal
- 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
Images
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21B—ROLLING OF METAL
- B21B1/00—Metal-rolling methods or mills for making semi-finished products of solid or profiled cross-section; Sequence of operations in milling trains; Layout of rolling-mill plant, e.g. grouping of stands; Succession of passes or of sectional pass alternations
- B21B1/16—Metal-rolling methods or mills for making semi-finished products of solid or profiled cross-section; Sequence of operations in milling trains; Layout of rolling-mill plant, e.g. grouping of stands; Succession of passes or of sectional pass alternations for rolling wire rods, bars, merchant bars, rounds wire or material of like small cross-section
- B21B1/18—Metal-rolling methods or mills for making semi-finished products of solid or profiled cross-section; Sequence of operations in milling trains; Layout of rolling-mill plant, e.g. grouping of stands; Succession of passes or of sectional pass alternations for rolling wire rods, bars, merchant bars, rounds wire or material of like small cross-section in a continuous process
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21B—ROLLING OF METAL
- B21B37/00—Control devices or methods specially adapted for metal-rolling mills or the work produced thereby
- B21B37/74—Temperature control, e.g. by cooling or heating the rolls or the product
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21B—ROLLING OF METAL
- B21B38/00—Methods or devices for measuring, detecting or monitoring specially adapted for metal-rolling mills, e.g. position detection, inspection of the product
- B21B38/006—Methods or devices for measuring, detecting or monitoring specially adapted for metal-rolling mills, e.g. position detection, inspection of the product for measuring temperature
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21B—ROLLING OF METAL
- B21B45/00—Devices for surface or other treatment of work, specially combined with or arranged in, or specially adapted for use in connection with, metal-rolling mills
- B21B45/004—Heating the product
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21B—ROLLING OF METAL
- B21B45/00—Devices for surface or other treatment of work, specially combined with or arranged in, or specially adapted for use in connection with, metal-rolling mills
- B21B45/02—Devices for surface or other treatment of work, specially combined with or arranged in, or specially adapted for use in connection with, metal-rolling mills for lubricating, cooling, or cleaning
- B21B45/0203—Cooling
- B21B45/0209—Cooling devices, e.g. using gaseous coolants
- B21B45/0215—Cooling devices, e.g. using gaseous coolants using liquid coolants, e.g. for sections, for tubes
- B21B45/0224—Cooling devices, e.g. using gaseous coolants using liquid coolants, e.g. for sections, for tubes for wire, rods, rounds, bars
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21B—ROLLING OF METAL
- B21B45/00—Devices for surface or other treatment of work, specially combined with or arranged in, or specially adapted for use in connection with, metal-rolling mills
- B21B45/04—Devices for surface or other treatment of work, specially combined with or arranged in, or specially adapted for use in connection with, metal-rolling mills for de-scaling, e.g. by brushing
- B21B45/08—Devices for surface or other treatment of work, specially combined with or arranged in, or specially adapted for use in connection with, metal-rolling mills for de-scaling, e.g. by brushing hydraulically
-
- 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
- Y02P70/00—Climate change mitigation technologies in the production process for final industrial or consumer products
- Y02P70/10—Greenhouse gas [GHG] capture, material saving, heat recovery or other energy efficient measures, e.g. motor control, characterised by manufacturing processes, e.g. for rolling metal or metal working
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Metal Rolling (AREA)
Abstract
The invention discloses a rolling process of 38CrMoAl round steel, which comprises the following process steps: heating a steel billet; descaling: the billet is sent into a high-pressure water descaling machine to remove primary scale on the surface, and the working pressure of high-pressure water is 16-18 MPa; initial rolling: rolling for 5-15 times by a two-roll reversible blooming mill, wherein the initial rolling temperature is more than or equal to 1050 ℃, and the continuous rolling temperature is more than or equal to 950 ℃; continuous rolling: rolling the steel into round steel with the diameter of 50-220 mm by a horizontal-vertical short stress continuous rolling unit, wherein the initial rolling temperature of the continuous rolling unit is more than or equal to 1000 ℃, and the final rolling temperature is more than or equal to 900 ℃; and (3) cooling control: the controlled bed and controlled cooling process comprises the steps of stacking cooling, close arrangement, tooth arrangement and addition of a heat insulation cover, wherein the starting temperature of the round steel entering the cooling bed is more than or equal to 700 ℃. The invention aims to provide a rolling process of 38CrMoAl round steel, which does not need an annealing process and reduces the hardness so as to facilitate processing.
Description
Technical Field
The invention relates to the technical field of metallurgy and rolling, in particular to a rolling process of 38CrMoAl round steel.
Background
The 38CrMoAl round steel has the advantages of high wear resistance, high fatigue strength, high strength and the like, and is commonly used for nitriding parts with accurate size, such as precision screw rods, precision gears and the like. The 38CrMoAl round steel mainly comprises the steps of smelting, casting and hot rolling, and the quality and the mechanical property of a final product are directly related to the rolling process. In the general rolling process, because the descaling is not thorough in the rolling process and the rolling procedure is to be optimized, the surface defects of the steel during hot rolling are more and the hardness is higher, and the defects are represented as folding, scratching, ears and the like; and the hardness is higher, so that the processing is difficult for users, and the annealing process must be added to reduce the hardness of the 38CrMoAl round steel in the prior art, so that the steps are complicated and the effect is poor. Therefore, the hot rolling process of the 38CrMoAl round steel needs to be improved.
Disclosure of Invention
In order to solve the technical problems, the invention aims to provide a rolling process of 38CrMoAl round steel, which does not need an annealing process and reduces the hardness so as to facilitate processing.
In order to solve the technical problems, the invention adopts the following technical scheme:
the invention relates to a rolling process of 38CrMoAl round steel, which comprises the following process flows of heating, initial rolling, continuous rolling, saw cutting and cooling bed, and is characterized by comprising the following specific steps:
heating: the temperature of the billet preheating section is 740 and 760 ℃, and the heating time is 20-90 min; the temperature of the heating section is 1150-1190 ℃, and the heating time is 20-80 min; the temperature of the soaking section is 1160-1190 ℃, the heating time is 20-80 min, and the steel billet is discharged after being completely and uniformly burnt;
descaling: the billet is sent into a high-pressure water descaling machine to remove primary scale on the surface, and the working pressure of high-pressure water is 16-18 MPa;
initial rolling: rolling for 5-15 times by a two-roll reversible blooming mill, wherein the initial rolling temperature is more than or equal to 1050 ℃, and the continuous rolling temperature is more than or equal to 950 ℃;
continuous rolling: rolling the steel into round steel with the diameter of 50-220 mm by a horizontal-vertical short stress continuous rolling unit, wherein the initial rolling temperature of the continuous rolling unit is more than or equal to 1000 ℃, and the final rolling temperature is more than or equal to 900 ℃;
and (3) cooling control: the controlled bed and controlled cooling process comprises the steps of stacking cooling, close arrangement, tooth arrangement and addition of a heat insulation cover, wherein the starting temperature of the round steel entering the cooling bed is more than or equal to 700 ℃.
Further, the temperature of the preheating section of the billet steel is 750 ℃, and the heating time is 50 min.
Further, the working pressure of high-pressure water is 17 MPa.
Further, the cross-sectional dimension of the billet is 150mmmm × 150mm to 280mm × 380 mmmm.
Further, the chemical composition of the round steel is calculated by weight percentage; 0.35-0.42% of C, 0.30-0.60% of Mn, 0.20-0.45% of Si, less than or equal to 0.030% of P, less than or equal to 0.030% of S, 1.35-1.65% of Cr, 0.15-0.25% of Mo, 0.70-1.10% of Al, less than or equal to 0.20% of Cu, less than or equal to 0.30% of Ni, and the balance of Fe and indispensable impurities.
Compared with the prior art, the invention has the beneficial technical effects that:
the invention aims to overcome the defects of high hardness, difficult descaling, poor surface quality of steel grade and the like in the conventional 38CrMoAl hot-rolled round steel production process, and provides a rolling process for the 38CrMoAl round steel.
Drawings
The invention is further illustrated in the following description with reference to the drawings.
FIG. 1 is a flow chart of hot rolling and controlled cooling process of 38CrMoAl round steel.
Detailed Description
The invention aims to provide a rolling process of 38CrMoAl round steel aiming at the defects of high hardness, difficult descaling, poor surface quality of steel grade and the like in the conventional 38CrMoAl hot rolled round steel production, and the rolling process is adjusted and optimized, and the hardness and the surface quality of the 38CrMoAl hot rolled round steel are enhanced by adopting multi-pass descaling rolling, controlling the rolling temperature and the temperature of a cooling bed, so that the yield is improved, and the enterprise cost is reduced.
And (3) scale breaking rolling, namely adding a set of high-pressure water scale removal device after the first pass and the second pass of hole position respectively after the blooming mill, breaking the scale in the rolling, and then removing the scale in a high-pressure water scale removal device after the blooming mill. The descaling procedure is recorded into the reduction procedure, and the method of descaling according to the rolling pass and the steel turning pass is called descaling rolling. The scale breaking rolling can remove unclean scale and secondary scale by high-pressure water, and effectively improve the surface quality of steel. And a descaling device is added behind the continuous rolling unit, which is a means for improving the surface quality of the steel grade again. The scale generation speed is high, and partial scale can still be generated in the process of feeding the steel strip into the continuous rolling unit after the steel strip is completely removed by the blooming mill, so that the scale removal device arranged behind the continuous rolling unit removes the partial scale, and the surface quality is ensured.
According to the invention, the primary oxide scales and the secondary oxide scales on the surface of the 38CrMoAl round steel are efficiently removed by the water descaling device between the high-pressure water descaling and high-pressure scale breaking rolling of the blooming mill and the continuous rolling mill, the removal rate is up to 99%, the process accidents caused by the pressing in of the oxide scales are greatly reduced, and the yield of the variety is improved.
Example 1
Selecting a billet with the section size of 150mm multiplied by 150mm, and the process comprises the following steps:
heating: putting the 38CrMoAl billet into a stepping heating furnace, wherein the temperature of the 38CrMoAl billet in a preheating section, a heating section and a soaking section finally reaches 1160 ℃, the temperature of the preheating section is 750 ℃, and the heating time is 20 min; the temperature of the heating section is 1150 ℃, and the heating time is 20 min; and the temperature of the soaking section is 1160 ℃, the heating time is 20min, and the 38CrMoAl steel billet is discharged after being completely, uniformly and thoroughly burnt.
Descaling: and (3) feeding the completely and uniformly fully burnt 38CrMoAl steel billet in the step two into a high-pressure water descaling machine to remove primary oxide scales on the surface, wherein the working pressure of high-pressure water during normal production is 15 MPa.
Cogging: and (3) turning the 38Cr Mo Al steel with the surface removed by the primary scale in the third step, rolling the steel by a reversible two-roll cogging mill for 5 times, performing scale breaking rolling for the first 4 times, and rolling the steel into square steel with the section size of 125 x 125, wherein the cogging temperature is 1100 ℃.
Continuous rolling: the 38CrMoAl steel billet is rolled into round steel with phi 100 by 8 horizontal-vertical short stress continuous rolling mills, the initial rolling temperature of the continuous rolling mill is 1000 ℃, and the final rolling temperature is 900 ℃. In 8 horizontal-vertical short stress continuous rolling units, descaling devices are arranged between 1 and 2 rolling mills and between 2 and 3 rolling mills.
And (3) cooling control: and (3) feeding the round steel into a cooling bed at the temperature of 700 ℃, performing two rows of pile cooling on the round steel on the cooling bed, wherein each tooth is provided with 2-3 layers of round steel, and the side plate of the heat-insulating cover is closed.
Example 2
Selecting a billet with the section size of 280mm multiplied by 380mm, and the process comprises the following steps:
heating: putting the 38CrMoAl billet into a stepping heating furnace, wherein the temperature of the 38CrMoAl billet in a preheating section, a heating section and a soaking section finally reaches 1170 ℃, the temperature of the preheating section is 750 ℃, and the heating time is 30 min; the temperature of the heating section is 1170 ℃, and the heating time is 30 min; and the temperature of the soaking section is 1170 ℃, the heating time is 30min, and the 38CrMoAl steel billet is discharged after being completely, uniformly and thoroughly burnt.
Descaling: and (3) feeding the completely and uniformly fully burnt 38CrMoAl steel billet in the step two into a high-pressure water descaling machine to remove primary oxide scales on the surface, wherein the working pressure of high-pressure water during normal production is 15 MPa.
Cogging: and (3) turning the 38CrMoAl steel with the surface subjected to primary scale removal in the third step, rolling the turned steel by a reversible two-roll cogging mill for 9 times, performing scale breaking rolling for the first 4 times, rolling the turned steel into square steel with the section size of 125 x 125, and performing cogging at 1100 ℃.
Continuous rolling: the 38CrMoAl billet is rolled into round steel with phi 50 by 8 horizontal-vertical short stress continuous rolling mills, the start rolling temperature of the continuous rolling mill is 1000 ℃, and the finish rolling temperature is 900 ℃. In 8 horizontal-vertical short stress continuous rolling units, descaling devices are arranged between 1 and 2 rolling mills and between 2 and 3 rolling mills.
And (3) cooling control: the temperature of the round steel entering the cooling bed is 700 ℃, two rows of pile cooling are carried out on the round steel entering the cooling bed, 2-3 layers of round steel are arranged on each tooth, and the side plates of the heat-insulating cover are closed.
According to the invention, the primary oxide scales and the secondary oxide scales on the surface of the 38CrMoAl round steel are efficiently removed by the water descaling device between the high-pressure water descaling and high-pressure scale breaking rolling of the blooming mill and the continuous rolling mill, the removal rate is up to 99%, the process accidents caused by the pressing in of the oxide scales are greatly reduced, and the yield of the variety is improved.
The chemical compositions of example 1 and example 2 are specified in table 1.
The Brinell hardness and mechanical property values of the round steel are shown in Table 2.
Table 1 chemical compositions of example 1 and example 2
TABLE 2 test results of mechanical properties of round steel
| Examples | Tensile strength/MPa | Yield strength/MPa | Brinell hardness |
| Example 1 | 1082 | 933 | 207 |
| Example 2 | 973 | 875 | 219 |
The above-described embodiments are merely illustrative of the preferred embodiments of the present invention, and do not limit the scope of the present invention, and various modifications and improvements of the technical solutions of the present invention can be made by those skilled in the art without departing from the spirit of the present invention, and the technical solutions of the present invention are within the scope of the present invention defined by the claims.
Claims (5)
1. A rolling process of 38CrMoAl round steel comprises the following process flows of heating, initial rolling, continuous rolling, saw cutting and cooling, and is characterized by comprising the following specific steps:
heating: the temperature of the billet preheating section is 740 and 760 ℃, and the heating time is 20-90 min; the temperature of the heating section is 1150-1190 ℃, and the heating time is 20-80 min; the temperature of the soaking section is 1160-1190 ℃, the heating time is 20-80 min, and the steel billet is discharged after being completely and uniformly burnt;
descaling: the billet is sent into a high-pressure water descaling machine to remove primary scale on the surface, and the working pressure of high-pressure water is 16-18 MPa;
initial rolling: rolling for 5-15 times by a two-roll reversible blooming mill, wherein the initial rolling temperature is more than or equal to 1050 ℃, and the continuous rolling temperature is more than or equal to 950 ℃;
continuous rolling: rolling the steel into round steel with the diameter of 50-220 mm by a horizontal-vertical short stress continuous rolling unit, wherein the initial rolling temperature of the continuous rolling unit is more than or equal to 1000 ℃, and the final rolling temperature is more than or equal to 900 ℃;
and (3) cooling control: the controlled bed and controlled cooling process comprises the steps of stacking cooling, close arrangement, tooth arrangement and addition of a heat insulation cover, wherein the starting temperature of round steel entering a cooling bed is more than or equal to 700 ℃.
2. The rolling process of 38CrMoAl round steel according to claim 1, wherein the temperature of the billet preheating section is 750 ℃ and the heating time is 50 min.
3. The rolling process of 38CrMoAl round steel according to claim 1, wherein the working pressure of high-pressure water is 17 MPa.
4. The rolling process of 38CrMoAl round steel according to claim 1, wherein the billet has a cross-sectional dimension of 150mm x 150mm to 280mm x 380 mm.
5. The rolling process of 38CrMoAl round steel according to claim 1, wherein the chemical composition of the round steel is calculated by weight percentage; 0.35-0.42% of C, 0.30-0.60% of Mn, 0.20-0.45% of Si, less than or equal to 0.030% of P, less than or equal to 0.030% of S, 1.35-1.65% of Cr, 0.15-0.25% of Mo, 0.70-1.10% of Al, less than or equal to 0.20% of Cu, less than or equal to 0.30% of Ni, and the balance of Fe and essential impurities.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210510947.1A CN114888079A (en) | 2022-05-11 | 2022-05-11 | Rolling process of 38CrMoAl round steel |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210510947.1A CN114888079A (en) | 2022-05-11 | 2022-05-11 | Rolling process of 38CrMoAl round steel |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN114888079A true CN114888079A (en) | 2022-08-12 |
Family
ID=82722210
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202210510947.1A Pending CN114888079A (en) | 2022-05-11 | 2022-05-11 | Rolling process of 38CrMoAl round steel |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN114888079A (en) |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106670230A (en) * | 2016-12-23 | 2017-05-17 | 江苏沙钢集团淮钢特钢股份有限公司 | Large-size rectangular steel production process with cogging, continuous rolling and cooling control combined |
| CN110180893A (en) * | 2019-04-03 | 2019-08-30 | 西宁特殊钢股份有限公司 | A kind of rolling mill practice for improving 38CrMoAl steel and rolling state tissue |
| CN111020387A (en) * | 2019-12-25 | 2020-04-17 | 南阳汉冶特钢有限公司 | Seawater corrosion resistant nitrided steel plate 38CrMoAl and production method thereof |
| CN111420985A (en) * | 2020-03-31 | 2020-07-17 | 湖南华菱湘潭钢铁有限公司 | Rolling process of 38CrMoAl round steel |
| CN113102527A (en) * | 2020-05-10 | 2021-07-13 | 湖南华菱湘潭钢铁有限公司 | Rolling process of 45Mn2 round steel |
| CN113102526A (en) * | 2020-05-10 | 2021-07-13 | 湖南华菱湘潭钢铁有限公司 | Rolling process of C45 round steel |
-
2022
- 2022-05-11 CN CN202210510947.1A patent/CN114888079A/en active Pending
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106670230A (en) * | 2016-12-23 | 2017-05-17 | 江苏沙钢集团淮钢特钢股份有限公司 | Large-size rectangular steel production process with cogging, continuous rolling and cooling control combined |
| CN110180893A (en) * | 2019-04-03 | 2019-08-30 | 西宁特殊钢股份有限公司 | A kind of rolling mill practice for improving 38CrMoAl steel and rolling state tissue |
| CN111020387A (en) * | 2019-12-25 | 2020-04-17 | 南阳汉冶特钢有限公司 | Seawater corrosion resistant nitrided steel plate 38CrMoAl and production method thereof |
| CN111420985A (en) * | 2020-03-31 | 2020-07-17 | 湖南华菱湘潭钢铁有限公司 | Rolling process of 38CrMoAl round steel |
| CN113102527A (en) * | 2020-05-10 | 2021-07-13 | 湖南华菱湘潭钢铁有限公司 | Rolling process of 45Mn2 round steel |
| CN113102526A (en) * | 2020-05-10 | 2021-07-13 | 湖南华菱湘潭钢铁有限公司 | Rolling process of C45 round steel |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN101481778B (en) | Austenic stainless steel strip and manufacturing method thereof | |
| CN102628148B (en) | Acid-washing hot-rolled low-carbon steel without line defects on surface and production method thereof | |
| CN111420985A (en) | Rolling process of 38CrMoAl round steel | |
| CN107974638A (en) | A kind of thickness of continuous casting billet manufacture reaches the manufacture method of 180mm rack steel plates | |
| CN106636747A (en) | Manufacturing method for producing commercial pure titanium plate by adopting double annealing of heavy and medium plate mill | |
| CN103562425A (en) | High carbon thin steel sheet and method for producing same | |
| CN109266815A (en) | The board-shape control method of press quenching high strength steel plate | |
| CN102199734B (en) | High-strength 301L stainless steel used for bus, and manufacture method thereof | |
| CN110453148A (en) | A kind of ultra-wide economizing type two phase stainless steel cut deal and its manufacturing method | |
| CN106702270B (en) | Think gauge great surface quality hot rolling opening plate and its manufacture method | |
| CN113549743B (en) | Method for controlling grain size of high-carbon ferritic stainless steel extra-thick plate | |
| CN104593698B (en) | Method for manufacturing high-strength cold-rolled weather resisting steel plates and high-strength cold-rolled weather resisting steel plates | |
| CN110157979B (en) | Rolling method for improving surface quality of steel plate | |
| CN111647811A (en) | Welding wire steel wire rod suitable for pickling-free shelling process and production method | |
| CN114888079A (en) | Rolling process of 38CrMoAl round steel | |
| CN113102526A (en) | Rolling process of C45 round steel | |
| CN111809122B (en) | Die pressing stainless steel plate and heat treatment method thereof | |
| CN113102527A (en) | Rolling process of 45Mn2 round steel | |
| CN110860558B (en) | Rolling method of ultra-wide and ultra-thick steel containment nuclear power steel | |
| CN115491592B (en) | 20MnCr5 gear steel and rolling method thereof | |
| KR20160066570A (en) | Method for manufacturing middle carbon alloy steels wire for cold forging capable of eliminating softening annealing treatment | |
| CN113102525A (en) | Rolling process of C50 round steel | |
| CN114752734B (en) | Hot rolling process method of X10CrAlSi18 heat-resistant stainless steel medium plate | |
| CN114196813B (en) | Heat treatment process for pre-hardening of 3Cr13 die steel medium plate | |
| CN117463770A (en) | 20CrMnTi steel and rolling method thereof |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination |