CN115074502A - Large-scale shaft forging and heat treatment process thereof - Google Patents
Large-scale shaft forging and heat treatment process thereof Download PDFInfo
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- CN115074502A CN115074502A CN202210856112.1A CN202210856112A CN115074502A CN 115074502 A CN115074502 A CN 115074502A CN 202210856112 A CN202210856112 A CN 202210856112A CN 115074502 A CN115074502 A CN 115074502A
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- C21D1/18—Hardening; Quenching with or without subsequent tempering
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- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D1/00—General methods or devices for heat treatment, e.g. annealing, hardening, quenching or tempering
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- C22C38/04—Ferrous alloys, e.g. steel alloys containing manganese
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- C22C38/00—Ferrous alloys, e.g. steel alloys
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- C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
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- C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
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Abstract
The invention belongs to the technical field of metal material heat treatment, and particularly relates to a large-scale shaft forging and a heat treatment process thereof, wherein the final forging residual temperature of the shaft forging is utilized, the original grain structure of the shaft forging is refined by adopting a light quenching process, the air cooling rate is controlled in sections by controlling the normalizing process of the shaft forging, the abnormal thick structure in the shaft forging can be eliminated by one-time normalizing treatment, the manufactured large-scale shaft forging has uniform structure, the grain size is more than 7 grades, the performance uniformity of the large-scale shaft forging is obviously improved, the large-scale shaft forging product meeting the requirements is obtained, the secondary normalizing treatment operation is omitted, the abnormal thick structure of the large-scale shaft forging is eliminated, and the production process and the production cost of the large-scale shaft forging are avoided being increased.
Description
Technical Field
The invention relates to the technical field of heat treatment of metal materials, in particular to a large-scale shaft forging and a heat treatment process thereof.
Background
The shaft element is mainly used as a support and a connecting element in mechanical equipment and is also a key output part for generating power by the equipment. The shaft part has a severe service environment and bears various complex stresses such as fatigue, bending, torsion, high-speed rotation, stretching, impact and the like. The mass of the shaft is therefore directly related to the safety of the operating equipment. The large shaft used by some large-scale equipment is manufactured by adopting a forging process for meeting the quality requirement of the shaft due to large size, and after processing and heat treatment, an abnormal thick structure often exists, so that the grain size of the shaft is seriously mixed with crystal, the performance of the shaft is uneven, and the operation requirement of the shaft cannot be met. After the occurrence of an abnormally coarse structure, the abnormal coarse structure is generally eliminated by a secondary heat treatment or a high-temperature homogenization treatment, which leads to an increase in the production process and the production cost of the shaft member.
Disclosure of Invention
The invention mainly aims to provide a large-scale shaft forging and a heat treatment process thereof, aiming at eliminating the abnormal thick structure of the large-scale shaft forging and avoiding increasing the production process and the production cost of the large-scale shaft forging.
To solve the above technical problem, according to an aspect of the present invention, the present invention provides the following technical solutions:
a heat treatment process of a large-scale shaft forging comprises the following steps:
s1, forging and forming
Forging and molding the shaft blank to obtain a shaft forging piece, and controlling the finish forging temperature to be 850 +/-50 ℃;
s2. light quenching
Putting the forged shaft forging into a water tank for 10-15s, and then, discharging water out of the water tank and carrying out air cooling;
s3, normalizing
Placing the shaft forging subjected to light quenching into a normalizing furnace, controlling the temperature rise rate of the furnace temperature to be less than or equal to 150 ℃/h, the normalizing temperature to be 870-;
and after the furnace is taken out, sectional air cooling control is adopted, the air cooling rate is controlled to be 300 ℃/h within 0-1h after the furnace is taken out, and the air cooling rate is controlled to be 150 ℃/h within 100 h after the furnace is taken out until the room temperature.
As the preferable scheme of the heat treatment process of the large-scale shaft forging, the heat treatment process comprises the following steps: the forging forming method also comprises the steps of before forging forming,
s0. axle blank preparation.
As the preferable scheme of the heat treatment process of the large-scale shaft forging, the heat treatment process comprises the following steps: the step S0 specifically includes the steps of,
s01, casting an ingot by die casting;
s02, heating and rolling the cast ingot to obtain a shaft blank.
As the preferable scheme of the heat treatment process of the large-scale shaft forging, the heat treatment process comprises the following steps: in the step S01, the superheat degree of the molten steel is 50-60 ℃ during die casting, and the temperature of an ingot mold is less than or equal to 100 ℃.
As the preferable scheme of the heat treatment process of the large-scale shaft forging, the heat treatment process comprises the following steps: in the step S02, the ingot heating temperature is 1250-.
As the preferable scheme of the heat treatment process of the large-scale shaft forging, the heat treatment process comprises the following steps: in the step S1, the shaft blank is heated in a heating furnace, the heating temperature is controlled to 1200 and 1250 ℃, and a radial forging machine is used for forging.
As the preferable scheme of the heat treatment process of the large-scale shaft forging, the heat treatment process comprises the following steps: in the step S2, after the water tank is drained, the shaft forging is placed in a cooling bed, is placed for air cooling, and is strictly forbidden to be cooled by heaping.
As the preferable scheme of the heat treatment process of the large-scale shaft forging, the heat treatment process comprises the following steps: in the step S3, the single layer of the shaft forging is placed in a normalizing furnace for normalizing.
In order to solve the above technical problem, according to another aspect of the present invention, the present invention provides the following technical solutions:
a large-scale shaft forging is prepared by adopting the heat treatment process.
As the preferred scheme of the large-scale shaft forging piece, the invention comprises the following steps: the mechanical properties of the large-scale shaft forging are as follows: r p0.2 ≥375MPa，R m ≥570MPa，A≥25%，A ku5 Not less than 50J; preferably, the mechanical properties of the large-size shaft forging are as follows: r p0.2 ≥390MPa，R m ≥600MPa，A≥25%，A ku5 ≥50J。
As the preferred scheme of the large-scale shaft forging piece, the invention comprises the following steps: the large-scale shaft forging part comprises the following components in percentage by weight: 0.32 to 0.38 percent of C, 0.17 to 0.46 percent of Si, 0.9 to 1.1 percent of Mn, less than or equal to 0.020 percent of P, less than or equal to 0.020 percent of S, less than or equal to 0.30 percent of Cr, less than or equal to 0.30 percent of Ni, less than or equal to 0.08 percent of Mo, 0.02 to 0.06 percent of V, and the balance of iron and inevitable impurities.
The invention has the following beneficial effects:
the invention provides a large-scale shaft forging and a heat treatment process thereof, wherein the final forging residual temperature of the shaft forging is utilized, the original grain structure of the shaft forging is refined by adopting a 'light quenching' process, the normalizing process of the shaft forging is controlled, the air cooling rate is controlled in sections, the abnormal thick structure in the shaft forging can be eliminated by one-time normalizing treatment, the manufactured large-scale shaft forging has uniform structure, the grain size is more than 7 grades, the performance uniformity of the large-scale shaft forging is obviously improved, the large-scale shaft forging product meeting the requirements is obtained, the secondary normalizing treatment operation is omitted, the production process and the production cost of the large-scale shaft forging are avoided being increased while the abnormal thick structure of the large-scale shaft forging is eliminated.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the structures shown in the drawings without creative efforts.
FIG. 1 is a microstructure view of a shaft forging of example 1;
FIG. 2 is a microstructure view of the shaft forging of example 2;
FIG. 3 is a microstructure view of the shaft forging of example 3;
FIG. 4 is a microstructure view of a shaft forging of comparative example 1;
FIG. 5 is a microstructure view of a shaft forging of comparative example 2;
FIG. 6 is a microstructure view of a shaft forging of comparative example 3;
FIG. 7 is a schematic view of a large shaft forging of the present invention.
The implementation, functional features and advantages of the present invention will be further described with reference to the accompanying drawings.
Detailed Description
The following will clearly and completely describe the technical solutions in the embodiments, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
The invention provides a large-scale shaft forging and a heat treatment process thereof, the manufactured large-scale shaft forging has uniform structure, the grain size is more than 7 grade, secondary normalizing treatment operation can be omitted, and the increase of the production process and the production cost of the large-scale shaft forging is avoided while the abnormal thick structure of the large-scale shaft forging is eliminated; the final forging residual temperature of the shaft forging is utilized, the original grain structure of the shaft forging is refined by adopting a 'light quenching' process, the air cooling rate is controlled in a segmented mode by controlling the normalizing process of the shaft forging, abnormal thick structures in the shaft forging can be eliminated through one-time normalizing treatment, and a large-scale shaft forging product meeting the requirements is obtained.
According to one aspect of the invention, the invention provides the following technical scheme:
a heat treatment process of a large-scale shaft forging comprises the following steps:
s1, forging and forming
Forging and molding the shaft blank to obtain a shaft forging piece, and controlling the finish forging temperature to be 850 +/-50 ℃;
s2. light quenching of shaft forging
Putting the forged shaft forging into a water tank for 10-15s, and then, discharging water out of the water tank and carrying out air cooling;
s3, normalizing the shaft forging
Placing the shaft forging subjected to light quenching into a normalizing furnace, controlling the temperature rise rate of the furnace temperature to be less than or equal to 150 ℃/h, the normalizing temperature to be 870-;
and after the furnace is taken out, sectional air cooling control is adopted, the air cooling rate is controlled to be 300 ℃/h within 0-1h after the furnace is taken out, and the air cooling rate is controlled to be 150 ℃/h within 100 h after the furnace is taken out until the room temperature.
After forging, the invention refines the original structure of the large-sized shaft forging by utilizing the heat energy of the forged shaft forging and adopting 'light quenching' treatment, thereby avoiding forming a coarse austenite structure; and finally, performing segmented cooling after shaft forging normalizing treatment, shortening austenite transformation time, eliminating coarse abnormal structures, and obviously improving the performance uniformity of the large shaft forging, wherein the manufactured large shaft forging has uniform structures, the grain size is above grade 7.
In the step S1, the shaft blank is heated in a heating furnace, the heating temperature is controlled to be 1200-1250 ℃, a radial forging machine is adopted for forging, and the finish forging temperature is controlled to be 850 +/-50 ℃; the heating temperature is, for example, but not limited to, any one of 1200 ℃, 1210 ℃, 1220 ℃, 1230 ℃, 1240 ℃, 1250 ℃ or a range between any two; the finish forging temperature is, for example, but not limited to, 800 ℃, 810 ℃, 820 ℃, 830 ℃, 840 ℃, 850 ℃, 860 ℃, 870 ℃, 880 ℃, 890 ℃, 900 ℃ or a range between any two of them.
In the step S2, the forged shaft forging is placed in a water tank for 10-15S, the shaft forging is immediately lifted out of the water tank and then placed on a cooling bed, the shaft forging is placed in a swinging way for air cooling, and the shaft forging is strictly forbidden to be stacked and cooled; the time for placing the shaft forging into the water tank is, for example, but not limited to, any one of 10s, 11s, 12s, 13s, 14s and 15s or a range between any two of the two.
In the step S3, the shaft forgings subjected to light quenching are placed into a normalizing furnace in a single layer without being stacked in multiple layers, so that mutual influence among the shaft forgings is avoided; controlling the temperature rise rate of the furnace temperature to be less than or equal to 150 ℃/h, the normalizing temperature to be 870-900 ℃, and the heat preservation time to be 3-5 h; and after the furnace is taken out, sectional air cooling control is adopted, the air cooling rate is controlled to be 300 ℃/h within 0-1h after the furnace is taken out, and the air cooling rate is controlled to be 150 ℃/h within 100 h after the furnace is taken out until the room temperature.
An upper limit of a temperature rise rate of the furnace temperature of the normalizing furnace is, for example, but not limited to, any one of 100 ℃/h, 110 ℃/h, 120 ℃/h, 130 ℃/h, 140 ℃/h, 150 ℃/h; the normalizing temperature is, for example, but not limited to, any one of 870 ℃, 875 ℃, 880 ℃, 885 ℃, 890 ℃, 895 ℃ and 900 ℃ or a range between any two of the same; the normalizing heat preservation time is, for example, but not limited to, any one of 3h, 3.5h, 4h, 4.5h and 5h or a range between any two of the two; the air cooling rate of 0-1h after the furnace discharge is, for example, but not limited to, any one of 250 ℃/h, 260 ℃/h, 270 ℃/h, 280 ℃/h, 290 ℃/h and 300 ℃/h or the range between any two of the two; the air cooling rate after 1h is, for example, but not limited to, any one of 100 ℃/h, 110 ℃/h, 120 ℃/h, 130 ℃/h, 140 ℃/h, 150 ℃/h, or a range between any two.
The forging forming method also comprises the following steps of before forging forming,
s0., preparing an axle blank, wherein the step S0 specifically comprises,
s01, casting a cast ingot by die casting; the superheat degree of the molten steel is controlled to be 50-60 ℃ during die casting, the temperature of an ingot mold is less than or equal to 100 ℃, so that the C, Mn component segregation of the molten steel is effectively reduced; the superheat degree of the molten steel is, for example, but not limited to, any one of 50 ℃, 51 ℃, 52 ℃, 53 ℃, 54 ℃, 55 ℃, 56 ℃, 57 ℃, 58 ℃, 59 ℃, 60 ℃ or a range between any two of them; the upper limit of the temperature of the ingot mold is, for example, but not limited to, any one of 100 ℃, 95 ℃, 90 ℃, 85 ℃, 80 ℃, 75 ℃ and 70 ℃.
S02, heating and rolling the cast ingot to obtain a shaft blank; the heating temperature is 1250-; the temperature ramp rate is, for example, but not limited to, any one of 100 ℃/h, 110 ℃/h, 120 ℃/h, 130 ℃/h or a range between any two; the shaft blank is a square blank or a round blank, and can be a square blank with the specification of 300mm multiplied by 300mm, 250mm multiplied by 250mm, 200mm multiplied by 200mm, 180mm multiplied by 180mm and the like, and a round blank with the specification of phi 300mm, phi 250mm, phi 200mm, phi 180mm and the like.
In order to solve the above technical problem, according to another aspect of the present invention, the present invention provides the following technical solutions:
a large-scale shaft forging is prepared by adopting the heat treatment process; the mechanical properties of the large-scale shaft forging are as follows: r p0.2 ≥375MPa，R m ≥570MPa，A≥25%，A ku5 Not less than 50J; preferably, the mechanical properties of the large-size shaft forging are as follows: r p0.2 ≥390MPa，R m ≥600MPa，A≥25%，A ku5 The thickness is more than or equal to 50J. The large shaft forging comprises the following components in percentage by weight: 0.32 to 0.38 percent of C, 0.17 to 0.46 percent of Si, 0.9 to 1.1 percent of Mn, less than or equal to 0.020 percent of P, less than or equal to 0.020 percent of S, less than or equal to 0.30 percent of Cr, less than or equal to 0.30 percent of Ni, less than or equal to 0.08 percent of Mo, 0.02 to 0.06 percent of V, and the balance of iron and inevitable impurities. Aiming at the phenomenon of abnormal thick structure of large-sized shaft forgings, the invention has the advantages that the deviation of C, Mn components in steel ingots is limited to be less than or equal to 0.05%, a certain amount of V is adopted for microalloying, the V has strong affinity with C, N in steel, and fine vanadium carbonitride is easily formed, so that the function of pinning crystal boundaries is realized, and the coarse grains are prevented.
The present invention will be described in further detail with reference to specific examples.
EBT-EAF smelting, LF ladle refining and VD vacuum treatment are adopted to smelt molten steel with target chemical components as shown in Table 1 for later use, and the following examples and comparative examples are carried out.
TABLE 1 target chemical composition (wt.%) for axle forgings
| C | Si | Mn | V | Cr | P | S | Fe |
| 0.36 | 0.30 | 1.00 | 0.05 | 0.15 | ≤0.008 | ≤0.003 | Balance of |
Example 1
A heat treatment process of a large-scale shaft forging comprises the following steps:
s01, when die casting is carried out, the temperature is 1555 ℃, the superheat degree of molten steel is 53 ℃, the temperature of an ingot mold is 54 ℃ so as to effectively reduce C, Mn component segregation of the molten steel;
s02, heating the ingot in a heating furnace after demolding, wherein the heating rate is 120 ℃/h, the set temperature is 1260 ℃, and rolling the ingot into a square billet with the specification of 250mm multiplied by 250 mm;
s1, heating a square billet in a heating furnace at 1220 ℃, forging the square billet into a required shaft forging piece according to a program set by a radial forging machine, and controlling the finish forging temperature to be 850 ℃;
s2, hanging the shaft forging into a water tank, quickly putting into water, immediately hanging the shaft forging out of the water tank after keeping for 12s, placing the shaft forging on a cooling bed, placing the shaft forging for air cooling, and strictly forbidding to cool the shaft forging in a pile;
s3, placing the shaft forging subjected to light quenching into a normalizing furnace in a single-layer mode, wherein the normalizing temperature is 880 ℃, the furnace temperature rising speed is 130 ℃/h, and the temperature is kept for 4 h;
after the shaft forging is taken out of the furnace, sectional air cooling control is adopted, the air cooling rate is 250 ℃/h after 0-1h, and the air cooling rate is 100 ℃/h after 1h until the temperature reaches the room temperature; the shaft forging after the primary normalizing treatment is directly machined on a lathe to obtain the axle with uniform structure and stable performance, and the grain size is 8 grade.
The microstructure and performance results of the large shaft forgings produced are shown in fig. 1 and table 2, respectively.
Example 2
A heat treatment process of a large-scale shaft forging comprises the following steps:
s01, when die casting is carried out, the temperature is 1557 ℃, the superheat degree of molten steel is 55 ℃, the temperature of an ingot mold is 63 ℃, so that the C, Mn component segregation of the molten steel is effectively reduced;
s02, heating the ingot in a heating furnace after demolding, wherein the heating rate is 110 ℃/h, the set temperature is 1270 ℃, and rolling the ingot into a square billet with the specification of 250mm multiplied by 250 mm;
s1, heating a square billet in a heating furnace at 1230 ℃, forging the square billet into a required shaft forging piece according to a program set by a radial forging machine, and controlling the finish forging temperature to 845 ℃;
s2, hanging the shaft forging into a water tank, quickly putting into water, immediately hanging the shaft forging out of the water tank after keeping 13s, placing the shaft forging on a cooling bed, placing the shaft forging for air cooling, and strictly forbidding to cool the shaft forging in a pile;
s3, placing the shaft forging subjected to light quenching into a normalizing furnace in a single layer mode, wherein the normalizing temperature is 870 ℃, the furnace temperature rising speed is 135 ℃/h, and the temperature is kept for 3 h;
after the shaft forging is discharged from the furnace, sectional air cooling control is adopted, the air cooling rate is 280 ℃/h after 0-1h, and the air cooling rate is 120 ℃/h after 1h until the temperature reaches the room temperature; the shaft forging after the primary normalizing treatment is directly machined on a lathe to obtain the axle with uniform structure and stable performance, and the grain size is 8 grade.
The microstructure and performance results of the large shaft forgings produced are shown in fig. 2 and table 2, respectively.
Example 3
A heat treatment process of a large-scale shaft forging comprises the following steps:
s01, when die casting is carried out, the temperature is 1562 ℃, the superheat degree of molten steel is 60 ℃, and the temperature of an ingot mold is 65 ℃ so as to effectively reduce C, Mn component segregation of the molten steel;
s02, heating the steel ingot in a heating furnace after demoulding, wherein the heating rate is 125 ℃/h, the set temperature is 1280 ℃, and rolling the steel ingot into a square billet with the specification of 250mm multiplied by 250 mm;
s1, heating a square billet in a heating furnace at 1240 ℃, forging the square billet into a required shaft forging piece according to a program set by a radial forging machine, and controlling the finish forging temperature to be 880 ℃;
s2, hanging the shaft forging into a water tank, quickly putting into water, immediately hanging the shaft forging out of the water tank after keeping for 15s, placing the shaft forging on a cooling bed, placing the shaft forging for air cooling, and strictly forbidding to cool the shaft forging in a pile;
s3, placing the shaft forging subjected to light quenching into a normalizing furnace in a single layer mode, wherein the normalizing temperature is 890 ℃, the furnace temperature rising speed is 150 ℃/h, and the temperature is kept for 4 h;
after the shaft forging is discharged from the furnace, sectional air cooling control is adopted, the air cooling rate is 300 ℃/h after 0-1h, and the air cooling rate is 100 ℃/h after 1h until the temperature reaches the room temperature; the shaft forging after the primary normalizing treatment is directly machined on a lathe to obtain the axle with uniform structure and stable performance, and the grain size is 7.5 grade.
The microstructure and performance results of the large shaft forgings produced are shown in fig. 3 and table 2, respectively.
Comparative example 1
The difference from the example 1 is that the superheat degree of the molten steel is 78 ℃ and the temperature of the ingot mold is 125 ℃.
The microstructure and performance results of the large shaft forgings produced are shown in fig. 4 and table 2, respectively.
Comparative example 2
The difference from embodiment 1 is that the light quenching treatment process is not adopted, and the shaft forging is directly cooled by stacking.
The microstructure and performance results of the large shaft forgings produced are shown in fig. 5 and table 2, respectively.
Comparative example 3
The difference from the embodiment 1 is that the shaft part is stacked in double layers during normalizing treatment, and the shaft part is naturally cooled in the air after being discharged from the normalizing furnace without graded air cooling control.
The microstructure and performance results of the large shaft forgings produced are shown in fig. 6 and table 2, respectively.
TABLE 2 properties of axle forgings of examples 1-3 and comparative examples 1-3
The results show that the invention solves the problem of large deviation of C, Mn element in steel by casting with low superheat degree and limiting the temperature of an ingot mould. In addition, the original grain structure of the shaft forging is refined by utilizing the forging finish forging residual heat and adopting a 'light quenching' process, the cooling speed is controlled by controlling the normalizing process of the shaft forging in a segmented air cooling mode, the abnormal thick structure in the shaft forging can be eliminated by one-time normalizing treatment, the large-scale shaft forging product meeting the requirements is obtained, and the secondary normalizing treatment operation is omitted.
The above description is only a preferred embodiment of the present invention, and not intended to limit the scope of the present invention, and all modifications and equivalents of the present invention, which are made by the present specification and directly/indirectly applied to other related technical fields within the spirit of the present invention are included in the scope of the present invention.
Claims (10)
1. The heat treatment process of the large-scale shaft forging is characterized by comprising the following steps of:
s1, forging and forming
Forging and molding the shaft blank to obtain a shaft forging piece, and controlling the finish forging temperature to be 850 +/-50 ℃;
s2. light quenching
Putting the forged shaft forging into a water tank for 10-15s, performing light quenching, and performing air cooling after the shaft forging is discharged from the water tank;
s3, normalizing
Placing the shaft forging subjected to light quenching into a normalizing furnace, controlling the temperature rise rate of the furnace temperature to be less than or equal to 150 ℃/h, the normalizing temperature to be 870-;
and after the furnace is taken out, sectional air cooling control is adopted, the air cooling rate is controlled to be 300 ℃/h within 0-1h after the furnace is taken out, and the air cooling rate is controlled to be 150 ℃/h within 100 h after the furnace is taken out until the room temperature.
2. The heat treatment process for large shaft forgings according to claim 1, wherein the step S1 is preceded by the step of,
s0., preparing an axle blank, wherein the step S0 specifically comprises:
s01, casting a cast ingot by die casting;
s02, heating and rolling the cast ingot to obtain a shaft blank.
3. The heat treatment process of the large shaft forging according to claim 2, wherein in the step S01, the superheat degree of molten steel in die casting is 50-60 ℃, and the temperature of an ingot mold is less than or equal to 100 ℃.
4. The heat treatment process for large shaft forgings as claimed in claim 2 or 3, wherein in the step S02, the ingot heating temperature is 1250-.
5. The heat treatment process for large shaft forgings as claimed in claim 1 or 2, wherein in step S1, the shaft blank is heated in a heating furnace at 1200-1250 ℃ by using a radial forging machine, and the finish forging temperature is controlled at 850 ± 50 ℃.
6. The heat treatment process of the large shaft forging according to claim 1 or 2, wherein in the step S2, after the water tank is drained, the shaft forging is placed on a cooling bed, is swung open and is placed for air cooling, and the shaft forging is strictly prohibited from being stacked for cooling.
7. The heat treatment process for the large shaft forging according to claim 1 or 2, wherein in the step S3, the shaft forging is placed in a normalizing furnace for normalizing treatment.
8. A large shaft forging prepared by the heat treatment process of any one of claims 1 to 7.
9. The large shaft forging of claim 8, wherein the large shaft forging is composed of, in weight percent: 0.32 to 0.38 percent of C, 0.17 to 0.46 percent of Si, 0.9 to 1.1 percent of Mn, less than or equal to 0.020 percent of P, less than or equal to 0.020 percent of S, less than or equal to 0.30 percent of Cr, less than or equal to 0.30 percent of Ni, less than or equal to 0.08 percent of Mo, 0.02 to 0.06 percent of V, and the balance of iron and inevitable impurities; the mechanical properties of the large-scale shaft forging are as follows: r p0.2 ≥375MPa，R m ≥570MPa，A≥25%，A ku5 ≥50J。
10. The large shaft forging according to claim 8 or 9, wherein the mechanical properties of the large shaft forging are as follows: r is p0.2 ≥390MPa，R m ≥600MPa，A≥25%，A ku5 ≥50J。
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Citations (17)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| 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 |
| KR20120138956A (en) * | 2011-06-16 | 2012-12-27 | 현대자동차주식회사 | Steel material having fine crystal garin and method for manufacturing product using the same |
| CN103789520A (en) * | 2013-09-27 | 2014-05-14 | 南京科润工业介质股份有限公司 | Uniform-speed cooling medium and application thereof in cooling control process after forging |
| CN103849746A (en) * | 2012-12-07 | 2014-06-11 | 中原特钢股份有限公司 | Thermal treatment process for 40CrNiMoA core rod and 40CrNiMoA core rod obtained through process |
| CN104439986A (en) * | 2014-12-30 | 2015-03-25 | 太原科技大学 | Method for continuously producing large long shaft type forged pieces through casting-forging heat |
| CN106425285A (en) * | 2015-08-06 | 2017-02-22 | 江苏金源锻造股份有限公司 | 34CrNiMo6 wind power main shaft forging forming method for low wind speed wind turbine set |
| CN107299203A (en) * | 2017-08-16 | 2017-10-27 | 太仓市顺昌锻造有限公司 | A kind of heat treatment method of forging |
| CN108441758A (en) * | 2018-02-12 | 2018-08-24 | 中国铁道科学研究院金属及化学研究所 | A kind of high-speed EMUs axle steel and preparation method thereof suitable for extremely frigid zones |
| CN109280759A (en) * | 2018-11-20 | 2019-01-29 | 江苏龙城精锻有限公司 | A kind of manufacturing method of integral fine crystal austenitic stainless steel hot forging |
| CN109898019A (en) * | 2019-02-26 | 2019-06-18 | 唐山志威科技有限公司 | Big section, high rigidity ZW872 mould steel preparation process |
| CN110257617A (en) * | 2019-07-10 | 2019-09-20 | 河南中原特钢装备制造有限公司 | The forging of big specification 20SiMn main shaft and heat treatment method |
| CN110387458A (en) * | 2019-08-23 | 2019-10-29 | 郑州机械研究所有限公司 | A kind of motor turning piston afterheat normalizing technique |
| CN112063823A (en) * | 2020-09-25 | 2020-12-11 | 马鞍山钢铁股份有限公司 | Alloy steel high-speed rail axle and production method thereof |
| CN113025793A (en) * | 2021-03-05 | 2021-06-25 | 无锡继平锻造有限公司 | High-purity fine-grain stainless steel forging and forging treatment process |
| CN113862433A (en) * | 2021-09-26 | 2021-12-31 | 汉德车桥(株洲)齿轮有限公司 | Spiral bevel gear grain refining control method |
| CN114410934A (en) * | 2022-01-25 | 2022-04-29 | 太原科技大学 | Method for refining coarse columnar crystal structure of electroslag remelting retaining ring steel |
| CN114438394A (en) * | 2022-01-26 | 2022-05-06 | 江苏宏晟模具钢材料科技有限公司 | Production process of pre-hardened high-polishing plastic mold steel |
-
2022
- 2022-07-21 CN CN202210856112.1A patent/CN115074502B/en active Active
Patent Citations (17)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR20120138956A (en) * | 2011-06-16 | 2012-12-27 | 현대자동차주식회사 | Steel material having fine crystal garin and method for manufacturing product using the same |
| 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 |
| CN103849746A (en) * | 2012-12-07 | 2014-06-11 | 中原特钢股份有限公司 | Thermal treatment process for 40CrNiMoA core rod and 40CrNiMoA core rod obtained through process |
| CN103789520A (en) * | 2013-09-27 | 2014-05-14 | 南京科润工业介质股份有限公司 | Uniform-speed cooling medium and application thereof in cooling control process after forging |
| CN104439986A (en) * | 2014-12-30 | 2015-03-25 | 太原科技大学 | Method for continuously producing large long shaft type forged pieces through casting-forging heat |
| CN106425285A (en) * | 2015-08-06 | 2017-02-22 | 江苏金源锻造股份有限公司 | 34CrNiMo6 wind power main shaft forging forming method for low wind speed wind turbine set |
| CN107299203A (en) * | 2017-08-16 | 2017-10-27 | 太仓市顺昌锻造有限公司 | A kind of heat treatment method of forging |
| CN108441758A (en) * | 2018-02-12 | 2018-08-24 | 中国铁道科学研究院金属及化学研究所 | A kind of high-speed EMUs axle steel and preparation method thereof suitable for extremely frigid zones |
| CN109280759A (en) * | 2018-11-20 | 2019-01-29 | 江苏龙城精锻有限公司 | A kind of manufacturing method of integral fine crystal austenitic stainless steel hot forging |
| CN109898019A (en) * | 2019-02-26 | 2019-06-18 | 唐山志威科技有限公司 | Big section, high rigidity ZW872 mould steel preparation process |
| CN110257617A (en) * | 2019-07-10 | 2019-09-20 | 河南中原特钢装备制造有限公司 | The forging of big specification 20SiMn main shaft and heat treatment method |
| CN110387458A (en) * | 2019-08-23 | 2019-10-29 | 郑州机械研究所有限公司 | A kind of motor turning piston afterheat normalizing technique |
| CN112063823A (en) * | 2020-09-25 | 2020-12-11 | 马鞍山钢铁股份有限公司 | Alloy steel high-speed rail axle and production method thereof |
| CN113025793A (en) * | 2021-03-05 | 2021-06-25 | 无锡继平锻造有限公司 | High-purity fine-grain stainless steel forging and forging treatment process |
| CN113862433A (en) * | 2021-09-26 | 2021-12-31 | 汉德车桥(株洲)齿轮有限公司 | Spiral bevel gear grain refining control method |
| CN114410934A (en) * | 2022-01-25 | 2022-04-29 | 太原科技大学 | Method for refining coarse columnar crystal structure of electroslag remelting retaining ring steel |
| CN114438394A (en) * | 2022-01-26 | 2022-05-06 | 江苏宏晟模具钢材料科技有限公司 | Production process of pre-hardened high-polishing plastic mold steel |
Non-Patent Citations (3)
| Title |
|---|
| A.ZIELIŃSKA-LIPIEC 等: "The influence of heat treatments on the microstructure of 9% chromium steels containing tungsten", 《JOURNAL OF MATERIALS PROCESSING TECHNOLOGY》 * |
| 朱腾等: "40Cr钢汽车转向节锻造余热淬火的研究", 《热处理》 * |
| 牛东亮: "大锻件生产过程中的晶粒控制", 《装备机械》 * |
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