CN111002000A - Processing method for improving grain size of flexible gear of harmonic reducer - Google Patents
Processing method for improving grain size of flexible gear of harmonic reducer Download PDFInfo
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- CN111002000A CN111002000A CN201911415526.5A CN201911415526A CN111002000A CN 111002000 A CN111002000 A CN 111002000A CN 201911415526 A CN201911415526 A CN 201911415526A CN 111002000 A CN111002000 A CN 111002000A
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- 230000000171 quenching effect Effects 0.000 claims abstract description 102
- 238000010791 quenching Methods 0.000 claims abstract description 101
- 238000010438 heat treatment Methods 0.000 claims abstract description 83
- 150000003839 salts Chemical class 0.000 claims abstract description 50
- 238000005496 tempering Methods 0.000 claims abstract description 48
- 238000005242 forging Methods 0.000 claims abstract description 42
- 238000003754 machining Methods 0.000 claims abstract description 15
- 238000005520 cutting process Methods 0.000 claims abstract description 9
- 239000007788 liquid Substances 0.000 claims description 24
- 238000000034 method Methods 0.000 claims description 20
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 20
- 238000004321 preservation Methods 0.000 claims description 17
- 238000010583 slow cooling Methods 0.000 claims description 16
- 238000003756 stirring Methods 0.000 claims description 11
- 239000010705 motor oil Substances 0.000 claims description 10
- 238000007599 discharging Methods 0.000 claims description 8
- 238000007670 refining Methods 0.000 claims description 5
- FBPFZTCFMRRESA-JGWLITMVSA-N D-glucitol Chemical compound OC[C@H](O)[C@@H](O)[C@H](O)[C@H](O)CO FBPFZTCFMRRESA-JGWLITMVSA-N 0.000 abstract description 12
- 239000000463 material Substances 0.000 description 10
- 229910001566 austenite Inorganic materials 0.000 description 9
- FAPWRFPIFSIZLT-UHFFFAOYSA-M Sodium chloride Chemical compound [Na+].[Cl-] FAPWRFPIFSIZLT-UHFFFAOYSA-M 0.000 description 8
- 239000008399 tap water Substances 0.000 description 8
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- 239000000306 component Substances 0.000 description 7
- 229910052799 carbon Inorganic materials 0.000 description 6
- 229910000851 Alloy steel Inorganic materials 0.000 description 5
- 229910000831 Steel Inorganic materials 0.000 description 5
- 238000001514 detection method Methods 0.000 description 5
- 230000005674 electromagnetic induction Effects 0.000 description 5
- 229910000734 martensite Inorganic materials 0.000 description 5
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- 229910000859 α-Fe Inorganic materials 0.000 description 5
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- 230000000052 comparative effect Effects 0.000 description 4
- 239000002826 coolant Substances 0.000 description 4
- KSOKAHYVTMZFBJ-UHFFFAOYSA-N iron;methane Chemical compound C.[Fe].[Fe].[Fe] KSOKAHYVTMZFBJ-UHFFFAOYSA-N 0.000 description 4
- 238000004519 manufacturing process Methods 0.000 description 4
- 239000011780 sodium chloride Substances 0.000 description 4
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- 230000005540 biological transmission Effects 0.000 description 3
- 238000012545 processing Methods 0.000 description 3
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 2
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- 230000000694 effects Effects 0.000 description 2
- 238000005530 etching Methods 0.000 description 2
- PCHJSUWPFVWCPO-UHFFFAOYSA-N gold Chemical compound [Au] PCHJSUWPFVWCPO-UHFFFAOYSA-N 0.000 description 2
- 239000010931 gold Substances 0.000 description 2
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- 229910052751 metal Inorganic materials 0.000 description 1
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- OXNIZHLAWKMVMX-UHFFFAOYSA-N picric acid Chemical class OC1=C([N+]([O-])=O)C=C([N+]([O-])=O)C=C1[N+]([O-])=O OXNIZHLAWKMVMX-UHFFFAOYSA-N 0.000 description 1
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23P—METAL-WORKING NOT OTHERWISE PROVIDED FOR; COMBINED OPERATIONS; UNIVERSAL MACHINE TOOLS
- B23P15/00—Making specific metal objects by operations not covered by a single other subclass or a group in this subclass
- B23P15/14—Making specific metal objects by operations not covered by a single other subclass or a group in this subclass gear parts, e.g. gear wheels
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- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- 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
- C21D1/18—Hardening; Quenching with or without subsequent tempering
- C21D1/25—Hardening, combined with annealing between 300 degrees Celsius and 600 degrees Celsius, i.e. heat refining ("Vergüten")
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- 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
- C21D1/26—Methods of annealing
- C21D1/28—Normalising
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- 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
- C21D9/00—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor
- C21D9/34—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor for tyres; for rims
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Abstract
The invention relates to the technical field of harmonic reducers, in particular to a processing method for improving the grain size of a flexible gear of a harmonic reducer, which comprises the following steps: (1) cutting a bar stock; (2) heating; (3) upsetting; (4) die forging; (5) air cooling; (6) isothermal normalizing; (7) rough machining; (8) secondary normalizing; (9) and (6) quenching and tempering. The average grain size after die forging and air cooling can reach 26-33 μm, namely the grain size can reach 7-7.5 grades, and the structure can not generate over-burning and forging cracks or banded structures. After secondary normalizing, the grain size can reach 10-10.5 grade, after twice salt bath heating and quenching, the grain size reaches 5-6 μm and the grain size reaches 12-12.5 grade through tempering, the microstructure is tempered sorbite and a small amount of troostite, the hardness is 34-38HRC, and the product of mechanical properties and strength and elongation can exceed 25000 MPa.
Description
Technical Field
The invention relates to the technical field of harmonic reducers, in particular to a processing method for improving the grain size of a flexible gear of a harmonic reducer.
Background
The flexible gear is a core component of the harmonic reducer and determines the service life, transmission precision and transmission efficiency of the harmonic reducer. Because the requirements on the mechanical property of materials, the tooth shape design and the manufacturing precision of the flexible gear are very high, the development level of China is still different from the advanced manufacturing level of Japan, America and parts of European Union, and therefore, the high-quality harmonic reducer still depends on import in China. Besides the influence of factors such as tooth profile design, manufacturing precision and surface treatment, the grain size of the flexible gear material is a key intrinsic material factor influencing the fatigue strength and the service life of the flexible gear.
The invention provides a method for improving a ribbon structure of a flexible gear raw material in the Chinese invention patent with the application publication number of CN108998643A, which adopts the processes of free forging, primary isothermal normalizing and secondary isothermal normalizing to improve the material with serious ribbon structure in the flexible gear raw material. The invention provides a harmonic reducer special steel flexible gear and a circulating heat treatment method thereof in the Chinese invention patent with the application publication number of CN109280851A, wherein the circulating heat treatment method comprises three steps of normalizing heat treatment, rough machining and quenching and tempering treatment, and after the circulating heat treatment method provided by the invention is adopted to treat the flexible gear made of special steel (medium-carbon high-strength quenched and tempered steel), the original austenite grains of the flexible gear can be refined and homogenized, and finally, the grain size of the flexible gear can reach 10 grades at most.
Although the patent improves the banded structure, the grain size of the flexible gear can reach 10 grades, the flexible gear needs to bear larger alternating load in the process of speed reduction transmission at present, and the flexible gear is easy to damage during working. The above-mentioned patent still fails to solve the problem, and it is necessary to develop a processing method for improving the fatigue strength and the service life of the flexible gear.
Disclosure of Invention
The invention aims to provide a processing method for improving the grain size of a flexible gear of a harmonic reducer, which has the advantages that the flexible gear with high fatigue strength and long service life can be processed.
The above object of the present invention is achieved by the following technical solutions:
a processing method for improving the grain size of a flexible gear of a harmonic reducer comprises the following steps:
(1) cutting a bar stock;
(2) heating for 9-11s at the temperature of 1120-1150 ℃;
(3) upsetting, wherein the upsetting temperature is controlled to be 1120-1150 ℃;
(4) die forging, wherein the initial forging temperature is controlled to 1100-1130 ℃, the final forging temperature is controlled to 880-920 ℃, and the wall thickness of the workpiece is controlled to 7.5 +/-0.2 mm;
(5) air cooling, wherein the average grain size of the flexible gear is 26-33 μm, and the grain size is 7-7.5 grade;
(6) isothermal normalizing, wherein the hardness of the flexible gear is 27-32 HRC;
(7) rough machining;
(8) secondary normalizing, wherein the grain size of the flexible gear is 10-10.5 grade:
(9) and (3) quenching and tempering, wherein the average grain size of the flexible gear is 5-6 mu m, the grain size is 12-12.5 grade, the hardness is 34-38HRC, and the product of strength and elongation is more than 25000 MPa.
By adopting the technical scheme, the flexible gear produced by the process can reach 5-6 μm in average grain size and 12-12.5 grade in grain size, the microstructure is tempered sorbite and a small amount of troostite, the hardness is 34-38HRC, and the product of mechanical properties and strength and elongation can exceed 25000 MPa. Compared with the prior art, the method has the advantages of small average grain size, high grain size grade and large product of strength and elongation.
The tempered troostite is ferrite and dispersed fine grained cementite which are not recrystallized and keep the martensite form. The tempered troostite is a mixture of polygonal equiaxed ferrite and granular cementite, the hardness of the tempered troostite is improved relative to that of tempered sorbite because a martensite structure is kept in the tempered troostite, and the plasticity of the tempered troostite is strong because the tempered troostite contains dispersed granular cementite. After the thermal refining treatment, the flexible gear is recovered and recrystallized, the solid solution strengthening effect is completely disappeared, the hardness and the strength are obviously reduced, and the plasticity and the toughness are obviously improved. Therefore, the flexible gear has excellent characteristics of high strength and high ductility and toughness as a whole.
Preferably, the air cooling in the step (5) is specifically as follows: the workpiece is placed on a mesh belt and rapidly cooled by a fan.
Preferably, the air cooling in the step (5) is specifically as follows: the cooling speed of the workpiece is 25-30 ℃/s, and the workpiece is placed in air for free cooling when the workpiece is cooled to 480-520 ℃.
By adopting the technical scheme, the average grain size can reach 26-33 μm after die forging and air cooling, namely the grain size can reach 7-7.5 grade, the structure can not be over-sintered, the forging crack or banded structure can not be generated, and the structure is relatively uniform.
Preferably, the isothermal normalizing in the step (6) is specifically as follows: heating the workpiece to 880-900 ℃ for heat preservation for 150-180min, then placing the workpiece in a slow cooling groove for slow cooling, placing the workpiece in a heat preservation furnace for heat preservation at 620 +/-5 ℃ for 120-150min when cooling to 600-650 ℃, and then discharging for air cooling.
By adopting the technical scheme, the hardness can be controlled to be 27-32HRC, the tissue and the hardness are uniform, and the rough machining is convenient.
Preferably, the secondary normalizing in the step (8) is specifically as follows: heating the workpiece to 840-860 ℃ for heat preservation for 60-70min, then taking the workpiece out of the furnace, placing the workpiece on a mesh belt for rapid cooling by a fan, and placing the workpiece in air for free cooling when the air cooling speed, namely the cooling speed of the workpiece, is 30-35 ℃/s, and the workpiece is cooled to 480-520 ℃.
The main purpose of isothermal normalizing is: firstly, the forging defects of ferrite segregation, banded structures and the like caused by improper cooling after die forging are eliminated, and the structures of all parts of a workpiece are consistent, so the process temperature of isothermal normalizing is higher than the temperature of secondary normalizing; and secondly, the crystal grains are refined, so that a higher cooling speed can be adopted during discharging and air cooling.
Preferably, the step (9) of thermal refining includes:
s2, primary salt bath heating: placing the preheated workpiece in 830 +/-5 ℃ molten salt, and preserving heat for 3-4min when the temperature of the molten salt is raised to 830 ℃ again;
s3, primary quenching; rapidly transferring the workpiece into quenching liquid for quenching, and opening stirring equipment in a quenching tank before quenching;
and S6, tempering.
Preferably, after the end of S3, S4, secondary salt bath heating: the operation of the secondary salt bath heating is consistent with that of the primary salt bath heating;
and (5) after the S4 is finished, carrying out S5 and secondary quenching: the operation of the secondary quenching is consistent with the operation of the primary quenching;
and after S5 is finished, S6 is carried out.
By adopting the technical scheme, the austenite grains are further refined by heating and quenching the salt bath twice.
Preferably, the S6 tempering is specifically: and (3) raising the temperature of a tempering furnace to 400 +/-5 ℃ in advance, then placing the workpiece subjected to secondary quenching in the tempering furnace, continuously heating to 585 +/-5 ℃, preserving heat for 3-4h, and then cooling to room temperature by water.
By adopting the technical scheme, the microstructure of the workpiece after the tempering treatment is tempered sorbite and a small amount of troostite, and the hardness is 34-38 HRC.
Preferably, before S2, S1, preheating is performed, specifically: heating the workpiece to 500 + -5 deg.C, and maintaining the temperature for 20-30min, wherein the preheating can be performed in a holding furnace, and the holding furnace can be a high temperature tempering furnace.
By adopting the technical scheme, the heating time for complete austenitizing of the tissue is shortened, and the growth of austenite grains is avoided.
Preferably, the quenching liquid comprises the following components in parts by volume:
5-10 parts of No. 10 engine oil and 90-95 parts of water;
in the primary quenching process, the quenching liquid is stirred by using stirring equipment.
In conclusion, the beneficial technical effects of the invention are as follows:
(1) the average grain size after die forging and air cooling can reach 26-33 μm, namely the grain size can reach 7-7.5 grade, the structure can not be over-sintered, the forging crack or banded structure can not be generated, and the structure is relatively uniform.
(2) Isothermal normalizing, hardness can be controlled at 27-32HRC, and the texture and hardness are uniform, so that rough machining is facilitated.
(3) During secondary normalizing, through rapid air cooling, austenite grains can be further refined on the basis of isothermal normalizing, and the grain size can reach 10-10.5 grades.
(4) The workpiece is preheated to 480-520 ℃, and then is placed in 830 ℃ molten salt for heat preservation, so that the temperature of the workpiece can be quickly raised to 830 ℃, the heating time for complete austenitizing of the tissue is shortened, and the growth of austenite grains is avoided.
(5) The austenite grains can be further refined by adopting salt bath heating and quenching twice.
(6) The specially prepared quenching liquid is used, so that the quenching structure is guaranteed to be fine-grained martensite (including cryptocrystalline martensite), and the workpiece is guaranteed not to generate quenching cracks during quenching.
(7) The flexible gear processed by the method has the average grain size of 5-6 mu m, the grain size of 12-12.5 grade, the microstructure of tempered sorbite and a small amount of troostite, the hardness of 34-38HRC and the product of strength and elongation of more than 25000 MPa.
Drawings
FIG. 1 is a flow chart of a processing method for increasing grain size of a flexible gear of a harmonic reducer.
FIG. 2 is a temperature versus time curve for a heat treatment according to the present invention.
Fig. 3 is a gold phase diagram of the flexspline after swaging and air cooling.
Fig. 4 is a metallographic image of the flexspline after secondary normalizing.
FIG. 5 is a grain diagram of the flexspline after thermal refining (saturated picric acid aqueous solution etching).
FIG. 6 is a gold phase diagram (4% nital etching) of the flexspline after thermal refining.
Detailed Description
The present invention will be described in further detail with reference to the accompanying drawings.
First, processing method
A processing method for improving grain size of a flexible gear of a harmonic reducer comprises the following steps:
(1) and cutting the bar stock. The bar stock is made of 40CrNiMoA medium-carbon low-alloy steel.
(2) And (4) heating. Electromagnetic induction heating is adopted, the heating time is 9-11s, and the heating temperature is 1120-.
(3) And (5) upsetting. The upsetting temperature is controlled to be 1120-1150 ℃.
(4) And (5) die forging. The initial forging temperature is controlled to 1100-1130 ℃, the final forging temperature is controlled to 880-920 ℃, and the wall thickness of the forging piece is controlled to 7.5 +/-0.2 mm. When the forging is carried out at 880-1130 ℃, the deformation resistance is small, and the forging crack of the workpiece can not be generated.
(5) And (6) air cooling. After the die forging is finished, the workpiece is placed on a mesh belt and is rapidly cooled by a fan, and the air cooling speed, namely the cooling speed of the workpiece is 25-30 ℃/s, and the workpiece is placed in the air for free cooling when the workpiece is cooled to 480-520 ℃.
The mesh belt is a conveying belt woven by steel wires, the fan is arranged above the mesh belt, the workpiece is arranged on the mesh belt and conveyed, and the fan blows air to the workpiece for cooling. The cooling rate may be controlled by adjusting the fan speed. The cooling speed of each surface of the workpiece can be basically consistent by arranging the mesh belt on the air cooling device, so that the tissue of the workpiece is more uniform. The rapid cooling speed is adopted to enable the temperature of the workpiece to rapidly pass through the temperature of the two-phase region, so that the structure segregation can be prevented, the formation of a banded ferrite structure can be prevented, the size of super-cooled austenite transformed into pearlite is smaller, the average grain size can reach 26-33 mu m, and the grain size can reach 7-7.5 grade.
(6) And (5) isothermal normalizing. Heating the workpiece to 880-900 ℃ for heat preservation for 150-180min, then placing the workpiece in a slow cooling groove for slow cooling, placing the workpiece in a heat preservation furnace for heat preservation at 620 +/-5 ℃ for 120-150min when cooling to 600-650 ℃, and then discharging for air cooling. The cooling medium of the slow cooling tank is circulating tap water, and the time required for cooling to 600-650 ℃ is 150-120 s. The holding furnace may be a high temperature tempering furnace.
Isothermal normalizing is adopted firstly, so that on one hand, the integral structure of the workpiece is uniform, the hardness of each position of the workpiece is basically consistent, the cutting processing is convenient, on the other hand, the size of crystal grains is consistent, and the consistency of the mechanical properties of each part of the workpiece is improved.
(7) And (5) rough machining. The single-side machining allowance of the rough machined workpiece is kept to be 1.5 +/-0.2 mm, namely the wall thickness of the workpiece is ensured to be 4-5 mm. The wall thickness can ensure thorough quenching in subsequent quenching and also ensure that the workpiece is not deformed during subsequent middle processing and finish processing.
(8) And (5) secondary normalizing. Heating the workpiece to 840-860 ℃ for heat preservation for 60-70min, then taking the workpiece out of the furnace, placing the workpiece on a mesh belt for rapid cooling by a fan, wherein the air cooling speed, namely the cooling speed of the workpiece, can adopt a larger cooling speed, namely 30-35 ℃/s, and then placing the workpiece in air for free cooling when the workpiece is cooled to 480-520 ℃.
After isothermal normalizing, the secondary normalizing is carried out again, the heating temperature is about 40 ℃ lower than that of the first isothermal normalizing, the heat preservation time is shortened, the secondary normalizing is carried out at a higher cooling speed, the grain size can be further refined, and the grain size can reach 10-10.5 grades.
(9) And (6) quenching and tempering.
And S1, preheating. Heating the workpiece to 500 + -5 deg.C, and maintaining the temperature for 20-30min, wherein the preheating can be performed in a holding furnace, and the holding furnace can be a high temperature tempering furnace.
The workpiece is preheated and kept warm for a certain time, so that the workpiece can be quickly heated to the required temperature when the primary salt bath is heated, the heating time before quenching is shortened, and the austenite grains in the heating process are prevented from growing. During preheating, the workpiece is placed in a material frame, and the material frame is formed by weaving steel wires.
S2, primary salt bath heating. Firstly, the temperature of molten salt is increased to 830 +/-5 ℃, then the preheated workpiece and the material frame are placed in the molten salt together, and the temperature is kept for 3-4min when the temperature of the molten salt is increased to 830 ℃ again.
The molten salt comprises KCl, NaCl and KNO as main components3And NaNO3A mixture of (a). By adopting salt bath heating, on one hand, the temperature of the workpiece in the material frame can be more uniform, on the other hand, the temperature of the workpiece can be rapidly increased, and further austenite grains are prevented from growing.
And S3, primary quenching. And rapidly transferring the workpiece and the material frame heated by the primary salt bath into a quenching tank for quenching.
The quenching medium used for quenching is specially prepared quenching liquid, the quenching liquid mainly comprises No. 10 engine oil and water, and the concentration of the engine oil water solution is 5-10% (volume ratio). The quenching liquid is filled in the quenching tank, the quenching tank is a containing tank, two electric stirrers are arranged in the containing tank, and when the material frame with the workpiece is immersed in the quenching liquid, the electric stirrers stir the quenching liquid, so that the temperature of the quenching liquid in the quenching tank is uniform, the cooling capacity of the quenching liquid is effectively improved, and the quenching effect is improved. The workpiece can be cooled to room temperature within 12-16s by using the specially prepared quenching liquid, namely the cooling speed can reach 50-70 ℃/s, and the cooling speed is higher than the oil cooling speed but lower than the water cooling speed. The cooling speed can ensure that the quenching structure is a fine-grained martensite structure and prevent the workpiece from generating quenching cracks after quenching.
After primary salt bath heating and primary quenching, the grain size can reach 10.5-11.5 grades.
S4, secondary salt bath heating: the operation of the secondary salt bath heating is consistent with the primary salt bath heating.
S5, secondary quenching: the operation of the secondary quenching is consistent with the primary quenching.
The grain size can be further improved to 12-12.5 grade by secondary salt bath heating and secondary quenching.
And S6, tempering. And (3) raising the temperature of a tempering furnace to 400 +/-5 ℃ in advance, then placing the secondarily quenched workpiece in the tempering furnace, and continuously heating to 585 +/-5 ℃ for heat preservation for 3-4 h.
The temperature of the tempering furnace is increased to 400 ℃ in advance, so that the workpiece can be quickly increased to 400 ℃, and the condition that the workpiece generates tempering brittleness in a middle temperature area during tempering is avoided. After the temperature is kept at 585 +/-5 ℃ for 3-4h, the tempered structure can be a tempered sorbite and a small amount of tempered troostite, the shape of ferrite in the sorbite is short rod-shaped, cementite is granular, and the tempered sorbite with the shape has high strength and plasticity.
(10) And (5) cooling the water to room temperature. And (3) placing the tempered workpiece in tap water to be cooled to room temperature.
Second, example and comparative example 1
A processing method for improving the grain size of a flexible gear of a harmonic reducer comprises the following steps:
(1) and cutting the bar stock. The bar stock is made of 40CrNiMoA medium-carbon low-alloy steel.
(2) And (4) heating. Electromagnetic induction heating is adopted, the heating time is 10s, and the heating temperature is 1135 ℃.
(3) And (5) upsetting. The upsetting temperature was 1130 ℃.
(4) And (5) die forging. The initial forging temperature is 1120 ℃, the final forging temperature is 900 ℃, and the wall thickness of the forged piece is 7.5 mm.
(5) And (6) air cooling. After the die forging is finished, the workpiece is placed on a mesh belt and is rapidly cooled by a fan, the air cooling speed, namely the cooling speed of the workpiece is 28 ℃/s, and the workpiece is placed in the air for free cooling when the workpiece is cooled to about 500 ℃.
(6) And (5) isothermal normalizing. Heating the workpiece to 890 ℃, preserving heat for 170min, then placing the workpiece in a slow cooling groove for slow cooling, placing the workpiece in a heat preserving furnace for preserving heat for 140min at 620 ℃ when cooling to 630 ℃, and then discharging and air cooling. The holding furnace adopts a high-temperature tempering furnace. The cooling medium of the slow cooling tank is circulating tap water, and the cooling time is 130 s.
(7) And (5) rough machining. The wall thickness of the workpiece after rough machining is 4.5 mm.
(8) And (5) secondary normalizing. Heating to 850 deg.C, maintaining for 65min, taking out, placing the workpiece on mesh belt, rapidly cooling with fan at air cooling speed of 33 deg.C/s, and cooling to about 500 deg.C, and placing in air for free cooling.
(9) And (6) quenching and tempering.
And S1, preheating. Heating to 500 deg.C, maintaining for 25min, preheating in a holding furnace, and heating in a high temperature tempering furnace.
S2, primary salt bath heating. And (3) placing the workpiece in the 830 ℃ molten salt, and preserving the heat for 210s when the temperature of the molten salt is increased to 830 ℃ again. The molten salt comprises KCl, NaCl and KNO as main components3And NaNO3A mixture of (a).
And S3, primary quenching. The workpiece heated by the primary salt bath is quickly transferred into a quenching tank for quenching, the used quenching medium is specially prepared quenching liquid, the main components of the quenching liquid are No. 10 engine oil and water, the concentration of the engine oil water solution is 6.5 percent (volume ratio), and the cooling speed of the workpiece is 65 ℃/s. And starting the stirring equipment before quenching to stir the quenching liquid.
S4, heating the secondary salt bath. The process of step S2 is repeated once for the once quenched workpiece.
And S5, secondary quenching. The process of step S3 is repeated once for the workpiece heated by the secondary salt bath.
And S6, tempering. The temperature of the tempering furnace is raised to 400 ℃ in advance, and then the workpiece subjected to secondary quenching is placed in the tempering furnace to be heated continuously to 585 ℃ and kept for 210 min.
And S7, cooling the water to room temperature. And (4) placing the tempered workpiece in tap water to cool to room temperature.
Through detection, the average grain size of the workpiece after die forging air cooling is 27.2 microns, and the grain size is 7.5 grade. The average grain size of the work piece after the secondary normalizing was 9.5 μm, and the grain size was 10.5 grade. The average grain size of the workpiece after tempering and water cooling is 5.5 mu m, and the grain size is between 12 grades and 12.5 grades. The microstructure is tempered sorbite and a small amount of troostite, and the hardness is 36.5 HRC. 1265MPa of tensile strength, 1060MPa of yield strength, 22 percent of elongation after fracture and 27830MPa of product of strength and elongation.
Example 2
A processing method for improving the grain size of a flexible gear of a harmonic reducer comprises the following steps:
(1) and cutting the bar stock. The bar stock is made of 40CrNiMoA medium-carbon low-alloy steel.
(2) And (4) heating. Electromagnetic induction heating is adopted, the heating time is 9s, and the heating temperature is 1120 ℃.
(3) And (5) upsetting. The upsetting temperature is 1120 ℃.
(4) And (5) die forging. The initial forging temperature is 1110 ℃, the final forging temperature is 880 ℃, and the wall thickness of the forged piece is 7.5 mm.
(5) And (6) air cooling. After die forging, the workpiece is placed on a mesh belt and is rapidly cooled by a fan, and the air cooling speed, namely the cooling speed of the workpiece is 25 ℃/s, and the workpiece is placed in the air for free cooling when the workpiece is cooled to about 500 ℃.
(6) And (5) isothermal normalizing. Heating the workpiece to 880 ℃, preserving heat for 180min, then placing the workpiece in a slow cooling groove for slow cooling, placing the workpiece in a heat preservation furnace for preserving heat for 150min at 620 ℃ when cooling to 620 ℃, and then discharging and air cooling. The holding furnace adopts a high-temperature tempering furnace. The cooling medium of the slow cooling tank is circulating tap water, and the cooling time is 122 s.
(7) And (5) rough machining. The wall thickness of the workpiece after rough machining is 4.5 mm.
(8) And (5) secondary normalizing. Heating to 840 deg.C, keeping the temperature for 70min, taking out, placing the workpiece on a mesh belt, rapidly cooling with fan at air cooling speed of 30 deg.C/s, and cooling to about 500 deg.C, and placing in air for free cooling.
(9) And (6) quenching and tempering.
And S1, preheating. Heating to 500 deg.C, maintaining for 28min, preheating in a holding furnace, and heating to high temperature.
S2, primary salt bath heating. And (3) placing the workpiece in the 830 ℃ molten salt, and preserving the heat for 230s when the temperature of the molten salt is raised to 830 ℃ again. The molten salt comprises KCl, NaCl and KNO as main components3And NaNO3A mixture of (a).
And S3, primary quenching. The workpiece heated by the primary salt bath is quickly transferred into a quenching tank for quenching, the used quenching medium is specially prepared quenching liquid, the main components of the quenching liquid are No. 10 engine oil and water, the concentration of the engine oil water solution is 6.5 percent (volume ratio), and the cooling speed of the workpiece is 65 ℃/s. And starting the stirring equipment before quenching to stir the quenching liquid.
S4, heating the secondary salt bath. The process of step S2 is repeated once for the once quenched workpiece.
And S5, secondary quenching. The process of step S3 is repeated once for the workpiece heated by the secondary salt bath.
And S6, tempering. The temperature of a tempering furnace is raised to 400 ℃ in advance, and then the workpiece subjected to secondary quenching is placed in the tempering furnace to be heated continuously to 585 ℃ and kept warm for 190 min.
And S7, cooling the water to room temperature. And (4) placing the tempered workpiece in tap water to cool to room temperature.
Through detection, the average grain size of the workpiece after die forging air cooling is 26.5 microns, and the grain size is 7.5 grade. The average grain size of the work piece after the secondary normalizing was 9.5 μm, and the grain size was 10.5 grade. The average grain size of the workpiece after tempering and water cooling is 5.7 mu m, and the grain size is between 12 grades and 12.5 grades. The microstructure is tempered sorbite and a small amount of troostite, and the hardness is 37.5 HRC. Tensile strength of 1272MPa, yield strength of 1055MPa, elongation after fracture of 21.5 percent and product of strength and elongation of 27348 MPa.
Example 3
A processing method for improving the grain size of a flexible gear of a harmonic reducer comprises the following steps:
(1) and cutting the bar stock. The bar stock is made of 40CrNiMoA medium-carbon low-alloy steel.
(2) And (4) heating. Electromagnetic induction heating is adopted, the heating time is 11s, and the heating temperature is 1150 ℃.
(3) And (5) upsetting. The upsetting temperature was 1145 ℃.
(4) And (5) die forging. The initial forging temperature is 1130 ℃, the final forging temperature is 918 ℃, and the wall thickness of the forged piece is 7.5 mm.
(5) And (6) air cooling. After the die forging is finished, the workpiece is placed on a mesh belt and is rapidly cooled by a fan, the air cooling speed, namely the cooling speed of the workpiece is 30 ℃/s, and the workpiece is placed in the air for free cooling when the workpiece is cooled to about 500 ℃.
(6) And (5) isothermal normalizing. Heating the workpiece to 900 ℃ and preserving heat for 150min, then placing the workpiece in a slow cooling groove for slow cooling, placing the workpiece in a heat preservation furnace for preserving heat for 150min at 620 ℃ when the workpiece is cooled to 635 ℃, and then discharging and air cooling. The holding furnace adopts a high-temperature tempering furnace. The cooling medium of the slow cooling tank is circulating tap water, and the cooling time is 140 s.
(7) And (5) rough machining. The wall thickness of the workpiece after rough machining is 4.5 mm.
(8) And (5) secondary normalizing. Heating to 860 deg.C, holding for 60min, taking out, placing the workpiece on mesh belt, rapidly cooling with fan at air cooling speed of 35 deg.C/s, and cooling to about 500 deg.C, and placing in air for free cooling.
(9) And (6) quenching and tempering.
And S1, preheating. Heating to 500 deg.C, maintaining for 22min, preheating in a holding furnace, and heating to high temperature.
S2, primary salt bath heating. And (3) placing the workpiece in the 830 ℃ molten salt, and preserving the heat for 190s when the temperature of the molten salt is raised to 830 ℃ again. Fusion furnaceThe salt comprises KCl, NaCl and KNO as main ingredients3And NaNO3A mixture of (a).
And S3, primary quenching. The workpiece heated by the primary salt bath is quickly transferred into a quenching tank for quenching, the used quenching medium is specially prepared quenching liquid, the main components of the quenching liquid are No. 10 engine oil and water, the concentration of the engine oil water solution is 6.5 percent (volume ratio), and the cooling speed of the workpiece is 67 ℃/s. And starting the stirring equipment before quenching to stir the quenching liquid.
S4, heating the secondary salt bath. The process of step S2 is repeated once for the once quenched workpiece.
And S5, secondary quenching. The process of step S3 is repeated once for the workpiece heated by the secondary salt bath.
And S6, tempering. The temperature of the tempering furnace is raised to 400 ℃ in advance, and then the workpiece subjected to secondary quenching is placed in the tempering furnace to be heated continuously to 585 ℃ and kept warm for 4 hours.
And S7, cooling the water to room temperature. And (4) placing the tempered workpiece in tap water to cool to room temperature.
Through detection, the average grain size of the workpiece after die forging air cooling is 29 microns, and the grain size is 7.5 grade. The average grain size of the work piece after the secondary normalizing is 10.5 mu m, and the grain size is 10.5 grade. The average grain size of the workpiece after tempering and water cooling is 5.3 mu m, and the grain size is between 12 grades and 12.5 grades. The microstructure is tempered sorbite and a small amount of troostite, and the hardness is 34.5 HRC. Tensile strength of 1240MPa, yield strength of 1010MPa, elongation after fracture of 20.5 percent and product of strength and elongation of 25420 MPa.
Comparative example 1
The comparative example is a processing method adopted by most domestic companies in the production of harmonic reducer flexible gears, and the key steps are as follows: (1) and cutting the bar stock. The bar stock is made of 40CrNiMoA medium-carbon low-alloy steel.
(2) And (4) heating. Electromagnetic induction heating is adopted, and the heating temperature is 1160 ℃.
(3) And (5) die forging. The initial forging temperature was 1160 ℃ and the final forging temperature was 820 ℃.
(4) And (6) normalizing. Heating to 870 ℃, preserving heat for 2h, then discharging from the furnace, and placing in the air for free cooling.
(5) And (5) rough machining. The wall thickness of the rough machined workpiece is 5 mm.
(6) And (6) quenching and tempering.
S1 is heated to 860 ℃ in a box type multipurpose furnace under the protective atmosphere, and the temperature is kept for 2.5 h. The protective atmosphere is a mixed gas of nitrogen and methanol.
And S2 quenching. The quenching medium is quenching oil.
And S3 tempering. Charging into a furnace at room temperature, heating to 600 ℃, and preserving heat for 3 hours.
S4 air cooling to room temperature. And (4) placing the tempered workpiece in air to cool to room temperature.
The detection shows that the average grain size of the flexible gear after die forging is 40 mu m, and the grain size is 6.5 grade. The average grain size of the normalized workpiece was 16.2 μm, and the grain size was grade 9. After the quenching and tempering, the average grain size of the flexible gear is 12.5 mu m, and the grain size is between 9.5 grade and 10 grade. The microstructure is tempered sorbite, and the hardness is 36 HRC. Tensile strength is 1095MPa, yield strength is 975MPa, elongation after fracture is 12%, and product of strength and elongation is 13140 MPa.
Comparative example 2
Referring to the Chinese patent with application publication No. CN109280851A, the highest grade of the grain size of the tempered flexible gear is 10 grade.
Third, data detection and analysis
1. Detecting the grain size of the flexible gear by referring to a GB/T6349 and 2017 metal average grain size determination method;
2. reference GB/T228.1-2010 metallic Material tensile test part 1: detecting the tensile strength, yield strength and elongation after fracture of the flexible gear by a room temperature test method;
3. the flexible wheel quasi-static fracture toughness (namely the product of strength and elongation) is detected by referring to a GB/T21143-2014 unified test method for the quasi-static fracture toughness of the metal material.
Table 1 comparison of the performance of the harmonic reducer flexspline produced by the present invention with the prior art
After tempering and cooling, the product of strength and elongation of the flexible gear is more than 25000 MPa. Table 1 shows the comparison between the performance of the harmonic reducer flexspline produced by the present invention and the performance of the flexspline produced by the prior art in other companies. The temperature-time profile of the heat treatment of the present invention is shown in FIG. 2.
As can be seen from the data in table 1, when the flexible gear is processed by using the processing method in the present application, the grain size of the flexible gear is effectively increased, the grain sizes in examples 1 to 3 are all greater than or equal to 12, and the tensile strength, the yield strength, the elongation after fracture, and the product of strength and elongation are significantly increased compared with the prior art.
The embodiments of the present invention are preferred embodiments of the present invention, and the scope of the present invention is not limited by these embodiments, so: all equivalent changes made according to the structure, shape and principle of the invention are covered by the protection scope of the invention.
Claims (10)
1. A processing method for improving the grain size of a flexible gear of a harmonic reducer is characterized by comprising the following steps: the method comprises the following steps:
(1) cutting a bar stock;
(2) heating for 9-11s at the temperature of 1120-1150 ℃;
(3) upsetting, wherein the upsetting temperature is controlled to be 1120-1150 ℃;
(4) die forging, wherein the initial forging temperature is controlled to 1100-1130 ℃, the final forging temperature is controlled to 880-920 ℃, and the wall thickness of the workpiece is controlled to 7.5 +/-0.2 mm;
(5) air cooling, wherein the average grain size of the flexible gear is 26-33 μm, and the grain size is 7-7.5 grade;
(6) isothermal normalizing, wherein the hardness of the flexible gear is 27-32 HRC;
(7) rough machining;
(8) secondary normalizing, wherein the grain size of the flexible gear is 10-10.5 grade:
(9) and (3) quenching and tempering, wherein the average grain size of the flexible gear is 5-6 mu m, the grain size is 12-12.5 grade, the hardness is 34-38HRC, and the product of strength and elongation is more than 25000 MPa.
2. The processing method for improving the grain size of the flexible gear of the harmonic reducer according to claim 1, wherein the processing method comprises the following steps: the air cooling in the step (5) is specifically as follows: the workpiece is placed on a mesh belt and rapidly cooled by a fan.
3. The processing method for improving the grain size of the flexible gear of the harmonic reducer according to claim 1, wherein the processing method comprises the following steps: the air cooling in the step (5) is specifically as follows: the cooling speed of the workpiece is 25-30 ℃/s, and the workpiece is placed in air for free cooling when the workpiece is cooled to 480-520 ℃.
4. The processing method for improving the grain size of the flexible gear of the harmonic reducer according to claim 1, wherein the processing method comprises the following steps: the isothermal normalizing in the step (6) comprises the following specific steps: heating the workpiece to 880-900 ℃ for heat preservation for 150-180min, then placing the workpiece in a slow cooling groove for slow cooling, placing the workpiece in a heat preservation furnace for heat preservation at 620 +/-5 ℃ for 120-150min when cooling to 600-650 ℃, and then discharging for air cooling.
5. The processing method for improving the grain size of the flexible gear of the harmonic reducer according to claim 1, wherein the processing method comprises the following steps: the secondary normalizing in the step (8) is specifically as follows: heating the workpiece to 840-860 ℃ for heat preservation for 60-70min, then taking the workpiece out of the furnace, placing the workpiece on a mesh belt for rapid cooling by a fan, and placing the workpiece in air for free cooling when the air cooling speed, namely the cooling speed of the workpiece, is 30-35 ℃/s, and the workpiece is cooled to 480-520 ℃.
6. The processing method for improving the grain size of the flexible gear of the harmonic reducer according to claim 1, wherein the processing method comprises the following steps: the step (9) of thermal refining comprises the following steps:
s2, primary salt bath heating: placing the preheated workpiece in 830 +/-5 ℃ molten salt, and preserving heat for 3-4min when the temperature of the molten salt is raised to 830 ℃ again;
s3, primary quenching; rapidly transferring the workpiece into quenching liquid for quenching, and opening stirring equipment in a quenching tank before quenching;
and S6, tempering.
7. The processing method for improving the grain size of the flexible gear of the harmonic reducer according to claim 6, wherein the processing method comprises the following steps: after the end of S3, S4, secondary salt bath heating: the operation of the secondary salt bath heating is consistent with that of the primary salt bath heating;
and (5) after the S4 is finished, carrying out S5 and secondary quenching: the operation of the secondary quenching is consistent with the operation of the primary quenching;
and after S5 is finished, S6 is carried out.
8. The processing method for improving the grain size of the flexible gear of the harmonic reducer according to claim 6 or 7, wherein the processing method comprises the following steps: s6, tempering specifically comprises the following steps: and (3) raising the temperature of a tempering furnace to 400 +/-5 ℃ in advance, then placing the workpiece subjected to secondary quenching in the tempering furnace, continuously heating to 585 +/-5 ℃, preserving heat for 3-4h, and then cooling to room temperature by water.
9. The processing method for improving the grain size of the flexible gear of the harmonic reducer according to claim 6, wherein the processing method comprises the following steps: before the step of S2, the step of preheating is S1: heating the workpiece to 500 + -5 deg.C, and maintaining the temperature for 20-30min, wherein the preheating can be performed in a holding furnace, and the holding furnace can be a high temperature tempering furnace.
10. The processing method for improving the grain size of the flexible gear of the harmonic reducer according to claim 6, wherein the processing method comprises the following steps: the quenching liquid comprises the following components in parts by volume:
5-10 parts of No. 10 engine oil and 90-95 parts of water;
in the primary quenching process, the quenching liquid is stirred by using stirring equipment.
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112359187A (en) * | 2020-10-29 | 2021-02-12 | 北京精密机电控制设备研究所 | Flexible gear material and heat treatment process |
| CN113249652A (en) * | 2021-05-13 | 2021-08-13 | 广东麦格智芯精密仪器有限公司 | Retained austenite-adjusted special steel for flexible gear and preparation method thereof |
| TWI763428B (en) * | 2021-04-15 | 2022-05-01 | 光隆精密工業股份有限公司 | Circular spline applied to harmonic drive, manufacturing method thereof and harmonic drive |
| CN116179831A (en) * | 2023-04-03 | 2023-05-30 | 贵州大学 | A Method of Improving the Fatigue Life of Harmonic Reducer Flex Spline Parts |
Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20100319484A1 (en) * | 2009-06-23 | 2010-12-23 | Harmonic Drive Systems Inc. | Wave Gear Device |
| US20160258522A1 (en) * | 2015-03-05 | 2016-09-08 | Californaia Institute of Technology | Systems and Methods for Implementing Tailored Metallic Glass-Based Strain Wave Gears and Strain Wave Gear Components |
| CN108044323A (en) * | 2017-11-24 | 2018-05-18 | 万鑫精工（湖南）有限公司 | A kind of production method of harmonic speed reducer |
| CN108340132A (en) * | 2017-01-25 | 2018-07-31 | 湖北科峰传动设备有限公司 | A kind of flexbile gear and its processing technology for harmonic wave speed reducing machine |
| CN108998643A (en) * | 2018-09-27 | 2018-12-14 | 东莞市国森科精密工业有限公司 | Method for improving banded structure of flexible gear raw material |
| CN109280851A (en) * | 2018-10-29 | 2019-01-29 | 西宁特殊钢股份有限公司 | Flexible wheel made of special steel for harmonic reducer and its cyclic heat treatment method |
| CN109538730A (en) * | 2018-11-13 | 2019-03-29 | 东莞市国森科精密工业有限公司 | Flexible gear with stress relief hole and preparation process thereof |
| CN110331348A (en) * | 2019-05-30 | 2019-10-15 | 深圳大学 | Amorphous alloy material, amorphous alloy flexbile gear and preparation method thereof |
| CN209621997U (en) * | 2019-02-15 | 2019-11-12 | 东莞市鑫拓智能机械科技有限公司 | An improved harmonic reducer flex wheel and harmonic reducer |
-
2019
- 2019-12-31 CN CN201911415526.5A patent/CN111002000B/en active Active
Patent Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20100319484A1 (en) * | 2009-06-23 | 2010-12-23 | Harmonic Drive Systems Inc. | Wave Gear Device |
| US20160258522A1 (en) * | 2015-03-05 | 2016-09-08 | Californaia Institute of Technology | Systems and Methods for Implementing Tailored Metallic Glass-Based Strain Wave Gears and Strain Wave Gear Components |
| CN108340132A (en) * | 2017-01-25 | 2018-07-31 | 湖北科峰传动设备有限公司 | A kind of flexbile gear and its processing technology for harmonic wave speed reducing machine |
| CN108044323A (en) * | 2017-11-24 | 2018-05-18 | 万鑫精工（湖南）有限公司 | A kind of production method of harmonic speed reducer |
| CN108998643A (en) * | 2018-09-27 | 2018-12-14 | 东莞市国森科精密工业有限公司 | Method for improving banded structure of flexible gear raw material |
| CN109280851A (en) * | 2018-10-29 | 2019-01-29 | 西宁特殊钢股份有限公司 | Flexible wheel made of special steel for harmonic reducer and its cyclic heat treatment method |
| CN109538730A (en) * | 2018-11-13 | 2019-03-29 | 东莞市国森科精密工业有限公司 | Flexible gear with stress relief hole and preparation process thereof |
| CN209621997U (en) * | 2019-02-15 | 2019-11-12 | 东莞市鑫拓智能机械科技有限公司 | An improved harmonic reducer flex wheel and harmonic reducer |
| CN110331348A (en) * | 2019-05-30 | 2019-10-15 | 深圳大学 | Amorphous alloy material, amorphous alloy flexbile gear and preparation method thereof |
Non-Patent Citations (2)
| Title |
|---|
| 尹荣森: "谐波齿轮传动柔轮的制造工艺", 《航天工艺》 * |
| 范又功: "《谐波齿轮传动技术手册》", 30 June 1995 * |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112359187A (en) * | 2020-10-29 | 2021-02-12 | 北京精密机电控制设备研究所 | Flexible gear material and heat treatment process |
| TWI763428B (en) * | 2021-04-15 | 2022-05-01 | 光隆精密工業股份有限公司 | Circular spline applied to harmonic drive, manufacturing method thereof and harmonic drive |
| CN113249652A (en) * | 2021-05-13 | 2021-08-13 | 广东麦格智芯精密仪器有限公司 | Retained austenite-adjusted special steel for flexible gear and preparation method thereof |
| CN116179831A (en) * | 2023-04-03 | 2023-05-30 | 贵州大学 | A Method of Improving the Fatigue Life of Harmonic Reducer Flex Spline Parts |
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