CN111979465A - High-entropy alloy for manufacturing flexible gear and processing method of flexible gear - Google Patents
High-entropy alloy for manufacturing flexible gear and processing method of flexible gear Download PDFInfo
- Publication number
- CN111979465A CN111979465A CN202010789581.7A CN202010789581A CN111979465A CN 111979465 A CN111979465 A CN 111979465A CN 202010789581 A CN202010789581 A CN 202010789581A CN 111979465 A CN111979465 A CN 111979465A
- Authority
- CN
- China
- Prior art keywords
- flexible gear
- entropy alloy
- blank
- temperature
- manufacturing
- 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.)
- Granted
Links
Images
Classifications
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C30/00—Alloys containing less than 50% by weight of each constituent
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F3/00—Manufacture of workpieces or articles from metallic powder characterised by the manner of compacting or sintering; Apparatus specially adapted therefor ; Presses and furnaces
- B22F3/02—Compacting only
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F3/00—Manufacture of workpieces or articles from metallic powder characterised by the manner of compacting or sintering; Apparatus specially adapted therefor ; Presses and furnaces
- B22F3/10—Sintering only
- B22F3/1003—Use of special medium during sintering, e.g. sintering aid
- B22F3/1007—Atmosphere
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F3/00—Manufacture of workpieces or articles from metallic powder characterised by the manner of compacting or sintering; Apparatus specially adapted therefor ; Presses and furnaces
- B22F3/17—Manufacture of workpieces or articles from metallic powder characterised by the manner of compacting or sintering; Apparatus specially adapted therefor ; Presses and furnaces by forging
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F3/00—Manufacture of workpieces or articles from metallic powder characterised by the manner of compacting or sintering; Apparatus specially adapted therefor ; Presses and furnaces
- B22F3/24—After-treatment of workpieces or articles
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F5/00—Manufacture of workpieces or articles from metallic powder characterised by the special shape of the product
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F9/00—Making metallic powder or suspensions thereof
- B22F9/02—Making metallic powder or suspensions thereof using physical processes
- B22F9/06—Making metallic powder or suspensions thereof using physical processes starting from liquid material
- B22F9/08—Making metallic powder or suspensions thereof using physical processes starting from liquid material by casting, e.g. through sieves or in water, by atomising or spraying
- B22F9/082—Making metallic powder or suspensions thereof using physical processes starting from liquid material by casting, e.g. through sieves or in water, by atomising or spraying atomising using a fluid
-
- 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
- C21D9/32—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor for gear wheels, worm wheels, or the like
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22F—CHANGING THE PHYSICAL STRUCTURE OF NON-FERROUS METALS AND NON-FERROUS ALLOYS
- C22F1/00—Changing the physical structure of non-ferrous metals or alloys by heat treatment or by hot or cold working
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F3/00—Manufacture of workpieces or articles from metallic powder characterised by the manner of compacting or sintering; Apparatus specially adapted therefor ; Presses and furnaces
- B22F3/24—After-treatment of workpieces or articles
- B22F2003/247—Removing material: carving, cleaning, grinding, hobbing, honing, lapping, polishing, milling, shaving, skiving, turning the surface
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F3/00—Manufacture of workpieces or articles from metallic powder characterised by the manner of compacting or sintering; Apparatus specially adapted therefor ; Presses and furnaces
- B22F3/24—After-treatment of workpieces or articles
- B22F2003/248—Thermal after-treatment
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F9/00—Making metallic powder or suspensions thereof
- B22F9/02—Making metallic powder or suspensions thereof using physical processes
- B22F9/06—Making metallic powder or suspensions thereof using physical processes starting from liquid material
- B22F9/08—Making metallic powder or suspensions thereof using physical processes starting from liquid material by casting, e.g. through sieves or in water, by atomising or spraying
- B22F9/082—Making metallic powder or suspensions thereof using physical processes starting from liquid material by casting, e.g. through sieves or in water, by atomising or spraying atomising using a fluid
- B22F2009/0824—Making metallic powder or suspensions thereof using physical processes starting from liquid material by casting, e.g. through sieves or in water, by atomising or spraying atomising using a fluid with a specific atomising fluid
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F9/00—Making metallic powder or suspensions thereof
- B22F9/02—Making metallic powder or suspensions thereof using physical processes
- B22F9/06—Making metallic powder or suspensions thereof using physical processes starting from liquid material
- B22F9/08—Making metallic powder or suspensions thereof using physical processes starting from liquid material by casting, e.g. through sieves or in water, by atomising or spraying
- B22F9/082—Making metallic powder or suspensions thereof using physical processes starting from liquid material by casting, e.g. through sieves or in water, by atomising or spraying atomising using a fluid
- B22F2009/0848—Melting process before atomisation
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F9/00—Making metallic powder or suspensions thereof
- B22F9/02—Making metallic powder or suspensions thereof using physical processes
- B22F9/06—Making metallic powder or suspensions thereof using physical processes starting from liquid material
- B22F9/08—Making metallic powder or suspensions thereof using physical processes starting from liquid material by casting, e.g. through sieves or in water, by atomising or spraying
- B22F9/082—Making metallic powder or suspensions thereof using physical processes starting from liquid material by casting, e.g. through sieves or in water, by atomising or spraying atomising using a fluid
- B22F2009/088—Fluid nozzles, e.g. angle, distance
Abstract
The application discloses a high-entropy alloy for manufacturing a flexible gear and a processing method of the flexible gear, belonging to the manufacturing technology of harmonic reducersThe field of the technology. The high-entropy alloy is FeCoCrNiMo with FCC type single-phase solid solution structure0.2C0.1High entropy alloy. The processing method of the flexible gear comprises the following steps: smelting FeCoCrNiMo0.2C0.1High-entropy alloy, preparation of high-entropy alloy powder, press forming, sintering, hot forging, high-temperature annealing, cryogenic treatment, machining forming and shot peening strengthening. The flexible gear prepared by the method has the average grain size of 3-4 microns, the tensile strength of over 1200MPa, the yield strength of over 900MPa, the elongation of over 30 percent and the product of strength and elongation of over 36000MPa, and has higher mechanical property and transmission performance, so that the service life of the harmonic reducer is prolonged.
Description
Technical Field
The application relates to the technical field of manufacturing of harmonic reducers, in particular to a high-entropy alloy for manufacturing a flexible gear and a processing method of the flexible gear.
Background
The harmonic reducer has the advantages of high bearing capacity, large transmission ratio, small volume, light weight, stable transmission, high transmission precision and the like, and is widely applied to the fields of aerospace, robots, electronics and the like. The harmonic reducer is mainly composed of three basic components, namely a rigid gear, a flexible gear and a wave generator. The rigid gear is an internal gear with higher rigidity, and the flexible gear is an easily-deformable thin-wall cylindrical external gear and is made of a material with better elasticity. The mouth end of the flexible gear extends into the rigid gear, the external teeth of the flexible gear are meshed with the internal teeth of the rigid gear, and when the wave generator is driven by the power mechanism, the external teeth of the flexible gear and the internal teeth of the rigid gear perform the reciprocating circulation of meshing, meshing and disengaging, so that the continuous rotation of the flexible gear is realized.
Therefore, the flexible gear is a core component of the harmonic reducer and is also the component which is most easily scrapped due to fatigue in the harmonic reducer, and the service life of the flexible gear determines the service life of the harmonic reducer in a certain sense. Therefore, researches on the flexible gear material and the flexible gear processing method are always hot spots in the field of harmonic reducers. At present, hot-rolled medium-carbon low-alloy steels such as 40CrNiMoA, 40CrA, 30CrNiMoA, 30CrMnSiA, 55Si2Mn are mostly used as materials for manufacturing the flexspline at home and abroad, and the most used material is 40 CrNiMoA. The existing flexible gear processing flow mainly comprises hot forging, normalizing, tempering, machining and shot peening, and the grain size generally does not exceed 11.5 grade. The defects of selecting hot-rolled medium-carbon low-alloy steel as a raw material are as follows: the structure uniformity is poor, the metallurgical defects are more, the phase composition is more complex, the fracture toughness is low and the damage tolerance is poor, so the service life of the harmonic reducer is generally not more than 20000 h. Based on the prior art, the service life of the harmonic reducer is difficult to be greatly broken through even through heat treatment, surface treatment or insubstantial process improvement. Therefore, it is urgent to intensively study the materials and manufacturing methods of the flexspline, and it is desired to develop more advanced flexspline materials and flexspline processing techniques to make the service life of the harmonic reducer longer.
Disclosure of Invention
In view of the defects of the prior art, the present application aims to provide a high-entropy alloy for manufacturing a flexible gear, so as to achieve the effect that the flexible gear manufactured by using the high-entropy alloy has higher mechanical properties and transmission properties.
The second purpose of the application is to provide a method for processing the flexible gear, so that the effect that the service life of the harmonic reducer can be prolonged by the flexible gear manufactured by the method is achieved.
The technical purpose of the application is realized by the following technical scheme:
a high entropy alloy for manufacturing a flexible gear is a high entropy alloy having a FCC type single phase solid solution structure.
By adopting the technical scheme, the high-entropy alloy is an alloy containing 5 or more than 5 elements, and the content of each element is 5-35% (mole fraction). Although the high-entropy alloy has complex components, the phase composition is simple, and the high-entropy alloy is generally in a single-phase or two-phase structure, and has good stability and high flexibility in the aspect of microstructure control. The high-entropy alloy has a plurality of excellent properties, such as high strength, high hardness, high wear resistance, high fracture toughness, excellent low-temperature performance and structural stability, good corrosion resistance, good oxidation resistance and the like.
There are two categories of high-entropy alloys, one is classified according to the photographic type: single phase, dual phase, eutectic and multi-phase high entropy alloys; the other is divided into the following according to the structure of the photograph: FCC type, BCC type, HCP type, amorphous type and intermetallic compound type.
According to the working principle of the flexible gear, when the flexible gear works, the cylinder part is subjected to periodic alternating elastic stress, and the tooth part is subjected to periodic frictional extrusion force. The high-entropy alloy with the FCC single-phase solid solution structure has the advantages of good phase structure stability, high fracture toughness and damage tolerance, good elastoplasticity and high friction resistance, so that the material is more suitable for being used as a flexible gear material.
Preferably, the high-entropy alloy is FeCoCrNiMo0.2C0.1Wherein Fe, Co, Cr and Ni are equal atomic ratio, Mo and C are atomic percentage of 0.2% and 0.1% respectively.
By adopting the technical scheme, in all high-entropy alloys, the FeCoCrNi base is the most extensive and mature type of research, and the FeCoCrNi base material belongs to an FCC single-phase solid solution structure and completely conforms to the selection reason of the FeCoCrNi base as a flexible gear material. The solid solution of FCC single phase is still obtained after adding 0.2% of Mo and 0.1% of C into FeCoCrNi matrix. Mo can refine crystal grains, C can be dissolved in a matrix to form an interstitial solid solution, so that lattice distortion is caused, the alloy layer fault energy is reduced, the lattice friction is improved, the dislocation slip mode is changed from wave slip to plane slip, and the dislocation structure is refined. Therefore, the alloy has both higher strength and higher plasticity.
The invention also aims to provide a method for processing the flexible gear, which comprises the following steps:
a. screening the types of the high-entropy alloys: selecting a high-entropy alloy with an FCC type single-phase solid solution structure as a flexible gear material;
b. designing chemical components of the high-entropy alloy: the high-entropy alloy is FeCoCrNiMo0.2C0.1Wherein Fe, Co, Cr and Ni are equal atomic ratio, Mo and C are atomic percentage of 0.2% and 0.1% respectively;
c. smelting a high-entropy alloy: smelting a raw material of the high-entropy alloy;
d. preparing high-entropy alloy powder: preparing the smelted high-entropy alloy into powder;
e. pressing and forming: pressing the high-entropy alloy powder into a green compact;
f. and (3) sintering: sintering and forming the pressed compact;
g. hot forging: forging the sintered compact into a flexible gear blank;
h. high-temperature annealing: annealing the flexspline blank at high temperature;
i. cryogenic treatment: carrying out cryogenic treatment on the flexible gear blank subjected to high-temperature annealing;
j. machining and forming: machining the soft gear blank subjected to the cryogenic treatment into a soft gear;
k. shot peening: and performing shot peening on the machined flexible gear.
By adopting the technical scheme, FeCoCrNiMo with an FCC type single-phase solid solution structure is selected and used in the application0.2C0.1The high-entropy alloy is used for manufacturing the flexible gear, the high-entropy alloy powder is prepared by adopting a gas atomization method, the chemical components and the microstructure of the powder are relatively uniform, the appearance of crystal grains is nearly spherical, and the sizes are highly concentrated. The pressed compact is sintered and then hot-forged, so that residual gaps in the alloy can be eliminated, nearly full compactness is realized, the original crystal boundary is eliminated, and the grain size can be effectively refined. Meanwhile, under a larger forging ratio, metastable-phase carbide is easy to precipitate in the forging process, and plays a role in strengthening. After the flexspline blank is subjected to high-temperature annealing treatment, the grain size can reach 3-4 mu m, the grain size reaches 13-13.5 grade, and the grain appearance can be further spheroidized. And then the stability of the microstructure is improved by cryogenic treatment, the strength and the plasticity are improved to a certain degree at the same time, the tensile strength exceeds 1200MPa, the yield strength exceeds 900MPa, the elongation exceeds 30%, and the product of strength and elongation exceeds 36000 MPa%. Compared with a flexible gear made of medium-carbon low-alloy steel, the flexible gear made of the high-entropy alloy material has the advantages that the product of strength and elongation is greatly improved, the fracture toughness and the damage tolerance are higher, and the service life of the harmonic reducer is longer.
Preferably, in the step C, a vacuum induction furnace is adopted to smelt the high-entropy alloy, and the surfaces of the raw materials of Fe, Co, Cr, Ni, Mo and C (graphite) are subjected to rust removal, dust removal and drying treatment before charging; the vacuum degree in the melting period is kept at 0.7-5 Pa, the vacuum degree in the refining period is kept at 5-30 Pa, the refining temperature is 1500-1530 ℃, and the time is kept for 30-50 min after refining is finished.
By adopting the technical scheme, the vacuum induction smelting adopts the induction coil as a heat source, and the heating temperature is regulated and controlled by regulating the heating current, so that the metal simple substances are melted and uniformly mixed to obtain the alloy melt with a certain proportion. The vacuum induction melting does not need repeated melting, and the element components of the high-entropy alloy containing certain low-melting-point elements can be accurately controlled.
Fe. The raw materials of Co, Cr, Ni, Mo and C (graphite) are all high-purity simple substances, and the surfaces of the raw materials need to be subjected to necessary rust removal, dust removal and drying treatment before charging, so that impurities can be prevented from polluting the alloy, the purity of the high-entropy alloy is ensured, and the manufactured flexible gear has better mechanical property and transmission property.
Preferably, in the step d, the high-entropy alloy powder is prepared by adopting a gas atomization method, and the atomization medium is N2The atomizing nozzle is designed in a circular seam mode, the aperture is 2mm, the diameter of the liquid guide pipe is 3.8mm, and the atomizing airflow pressure is 0.8 MPa.
By adopting the technical scheme, the alloy melt smelted by the induction furnace meets high-speed airflow, the alloy melt is atomized into fine droplets immediately, and then the fine droplets are rapidly cooled in the atomizing cylinder to form alloy powder. The high-entropy alloy powder is prepared by adopting a gas atomization method, and the cooling rate can reach 1 multiplied by 105~1×106And the gas atomization method can fully alloy, the chemical components and the microstructure of the prepared powder are uniform, the morphology is nearly spherical, the grain size is highly concentrated and can reach 30-35 mu m, so that the gas atomization method is a preparation method generally adopted in mass production at present, and the gas atomization method is economical for preparing high-entropy alloy powder.
Preferably, in the step e, the high-entropy alloy powder is pressed into a flat thin cylindrical pressed blank by adopting a warm-pressing forming process, the pressure is 600-700 MPa, the pressing time is 3-4 min, and the pressing temperature is 150 +/-5 ℃.
By adopting the technical scheme, the pressed compact with high density and high performance can be obtained by one-time pressing and one-time sintering. This application makes high entropy alloy powder densify through warm compaction, and the compact density is high, the performance is good, and the unburned bricks release force is low, intensity is big, the yield is high. The warm-pressing forming has low production cost and easy control of product quality, thereby being suitable for mass production.
The compact is flat and thin and cylindrical, the structure is simple, and the die is easy to demold after being pressed, so that the use of a demolding lubricant is not recommended, and in addition, the alloy is easy to stain after the demolding lubricant is added.
Preferably, in the step f, the green compact is sintered and formed by a vacuum sintering furnace, and the sintering temperature is 1100-1150 ℃.
By adopting the technical scheme, the sintering temperature is set to 1100-1150 ℃, and the sintering temperature is higher than 1150 ℃ or lower than 1100 ℃ to generate adverse effects on the subsequent process and the performance of the flexible gear.
Preferably, in the step g, a hot forging process is adopted, the green compact is directly forged into a flexible gear blank after sintering, hot die forging is adopted, the temperature of a die is 920 ℃, the strain rate is 0.01m/s, and the blank after hot forging is air-cooled.
By adopting the technical scheme, the residual gap in the pressed compact can be eliminated through hot forging, nearly full-compact is realized, the original crystal boundary is eliminated, the grain size can be effectively refined, and meanwhile, under a larger forging ratio, metastable-phase carbide is separated out from a solid solution in the forging process to play a role in strengthening.
Preferably, in the step h, the flexspline blank is subjected to heat preservation for 85-95 min in a high-temperature annealing furnace at 595-605 ℃, and then taken out of the furnace for air cooling.
By adopting the technical scheme, the forging stress can be eliminated by high-temperature annealing of the flexspline blank, the size of the grains can be further refined to 3-4 mu m, and the appearance of the grains is further spheroidized.
Preferably, in the step i, the annealed flexible gear blank is subjected to cryogenic treatment, and the cryogenic treatment is carried out in a liquid nitrogen box at the temperature of-150 to-140 ℃ for 20 to 30min, and then the blank is taken out of the box and rewarming is carried out.
By adopting the technical scheme, the annealed flexible gear blank is subjected to cryogenic treatment, the stability of a microstructure is improved, the strength and the plasticity are improved to a certain degree at the same time, the tensile strength exceeds 1200MPa, the yield strength exceeds 900MPa, the elongation exceeds 30%, and the product of strength and elongation exceeds 36000 MPa%.
Preferably, in step j, the cryogenic-treated flexible gear blank is machined into a flexible gear.
By adopting the technical scheme, because the alloy has higher hardness, the machining cutting and grinding allowance is as small as possible. The purpose of machining is to remove oxide skin on the surface of the flexible gear blank and achieve finishing forming.
Preferably, in step k, shot peening is performed on the machined flexible gear, the diameter of the shot is 0.18mm, the material of the shot is ZG30, the distance between spray guns is 120mm, the spray angle is 90 degrees, the shot peening pressure is 0.6MPa, and the spray time is 20 s.
By adopting the technical scheme, the machining residual tensile stress on the surface of the flexible gear can be effectively removed through shot peening, the tensile stress on the surface before shot peening is 350-450 MPa, the compressive stress on the surface after shot peening is 500-600 MPa, and simultaneously the machining tool marks on the surface can be eliminated.
In summary, the present application has the following beneficial effects:
1. FeCoCrNiMo with FCC single-phase solid solution structure is adopted in the application0.2C0.1The high-entropy alloy has the advantages of good phase structure stability, high fracture toughness and damage tolerance, good elastoplasticity and high friction resistance;
2. by using FeCoCrNiMo0.2C0.1The average grain size of a flexible gear prepared from the high-entropy alloy is 3-4 mu m, the tensile strength exceeds 1200MPa, the yield strength exceeds 900MPa, the elongation exceeds 30%, the product of strength and elongation exceeds 36000MPa, and the service life of the harmonic reducer can be prolonged;
3. the flexible gear processing method is low in production cost, easy to control product quality and suitable for large-scale industrial production.
Drawings
Fig. 1 is a process flow diagram of the flexible gear processing method of the present application.
Detailed Description
The present application will be described in further detail with reference to the accompanying drawings and examples.
The equipment and model used in examples 1-4 of the present application are shown in Table 1.
Example 1
A method for processing a flexible gear comprises the following steps:
a. screening the types of the high-entropy alloys, and selecting the high-entropy alloys with FCC type single-phase solid solution structures as flexible gear materials;
b. designing chemical components of the high-entropy alloy: the high-entropy alloy is FeCoCrNiMo0.2C0.1Wherein the mol ratios of Fe, Co, Cr and Ni are 24.925%, the mol ratio of Mo is 0.2% and the mol ratio of C is 0.1%;
c. smelting a high-entropy alloy: smelting high-entropy alloy by using a vacuum induction furnace, and carrying out rust removal, dust removal and drying treatment on the surfaces of raw materials of Fe, Co, Cr, Ni, Mo and C (graphite) before charging; the vacuum degree in the melting period is kept at 0.7Pa, the vacuum degree in the refining period is kept at 5Pa, the refining temperature is 1530 ℃, and the holding time is 30min after the refining is finished.
d. Preparing high-entropy alloy powder: preparing high-entropy alloy powder by adopting a gas atomization method; the atomizing medium is N2The atomizing nozzle is designed in a circular seam mode, the aperture is 2mm, the diameter of the liquid guide pipe is 3.8mm, and the atomizing airflow pressure is 0.8 MPa;
e. pressing and forming: pressing the high-entropy alloy powder into a flat thin cylindrical pressed blank by adopting a warm compaction process, wherein the pressure is 700MPa, the holding time is 3min, and the pressing temperature is 155 ℃;
f. and (3) sintering: sintering and forming the pressed compact by adopting a vacuum sintering furnace, wherein the sintering temperature is 1150 ℃;
g. hot forging: directly forging the pressed blank into a flexible wheel blank after sintering by adopting a hot forging process, and performing hot die forging at the die temperature of 920 ℃ and the strain rate of 0.01m/s, and performing air cooling on the blank after the hot forging;
h. high-temperature annealing: keeping the temperature of the flexspline blank at 595 ℃ in a high-temperature annealing furnace for 95min, and then discharging the flexspline blank out of the furnace for air cooling;
i. cryogenic treatment: carrying out cryogenic treatment on the annealed flexible gear blank, and carrying out cryogenic treatment in a liquid nitrogen box at the temperature of-150 ℃ for 20min and then taking out of the box for rewarming;
j. machining and forming: machining the soft gear blank subjected to the cryogenic treatment into a soft gear;
k. shot peening: shot peening is carried out on the machined flexible gear, the diameter of a shot is 0.18mm, the material of the shot is ZG30, the distance between spray guns is 120mm, the spraying angle is 90 degrees, the shot peening pressure is 0.6MPa, and the spraying time is 20 s. The tensile stress of the surface before shot blasting is 450MPa, and the compressive stress of the surface after shot blasting is 600 MPa.
Example 2
A method for processing a flexible gear comprises the following steps:
a. screening the types of the high-entropy alloys, and selecting the high-entropy alloys with FCC type single-phase solid solution structures as flexible gear materials;
b. designing chemical components of the high-entropy alloy: the high-entropy alloy is FeCoCrNiMo0.2C0.1Wherein the mol ratios of Fe, Co, Cr and Ni are 24.925%, the mol ratio of Mo is 0.2% and the mol ratio of C is 0.1%;
c. smelting a high-entropy alloy: smelting high-entropy alloy by using a vacuum induction furnace, and carrying out rust removal, dust removal and drying treatment on the surfaces of raw materials of Fe, Co, Cr, Ni, Mo and C (graphite) before charging; the vacuum degree in the melting period is kept at 5Pa, the vacuum degree in the refining period is kept at 30Pa, the refining temperature is 1500 ℃, and the holding time is 50min after the refining is finished.
d. Preparing high-entropy alloy powder: preparing high-entropy alloy powder by adopting a gas atomization method; the atomizing medium is N2The atomizing nozzle is designed in a circular seam mode, the aperture is 2mm, the diameter of the liquid guide pipe is 3.8mm, and the atomizing airflow pressure is 0.8 MPa;
e. pressing and forming: pressing the high-entropy alloy powder into a flat thin cylindrical pressed blank by adopting a warm compaction process, wherein the pressure is 600MPa, the holding time is 4min, and the pressing temperature is 145 ℃;
f. and (3) sintering: sintering the pressed blank by using a vacuum sintering furnace at the sintering temperature of 1100 ℃;
g. hot forging: directly forging the pressed blank into a flexible wheel blank after sintering by adopting a hot forging process, and performing hot die forging at the die temperature of 920 ℃ and the strain rate of 0.01m/s, and performing air cooling on the blank after the hot forging;
h. high-temperature annealing: keeping the temperature of the flexspline blank in a high-temperature annealing furnace at 605 ℃ for 85min, and then discharging the flexspline blank out of the furnace for air cooling;
i. cryogenic treatment: carrying out cryogenic treatment on the annealed flexible gear blank, and carrying out cryogenic treatment in a liquid nitrogen box at the temperature of-140 ℃ for 30min and then taking out of the box for rewarming;
j. machining and forming: machining the soft gear blank subjected to the cryogenic treatment into a soft gear;
k. shot peening: shot peening is carried out on the machined flexible gear, the diameter of a shot is 0.18mm, the material of the shot is ZG30, the distance between spray guns is 120mm, the spraying angle is 90 degrees, the shot peening pressure is 0.6MPa, and the spraying time is 20 s. The surface tensile stress before shot blasting is 350MPa, and the surface compressive stress after shot blasting is 500 MPa.
Example 3
A method for processing a flexible gear comprises the following steps:
a. screening the types of the high-entropy alloys, and selecting the high-entropy alloys with FCC type single-phase solid solution structures as flexible gear materials;
b. designing chemical components of the high-entropy alloy: the high-entropy alloy is FeCoCrNiMo0.2C0.1Wherein the mol ratios of Fe, Co, Cr and Ni are 24.925%, the mol ratio of Mo is 0.2% and the mol ratio of C is 0.1%;
c. smelting a high-entropy alloy: smelting high-entropy alloy by using a vacuum induction furnace, and carrying out rust removal, dust removal and drying treatment on the surfaces of raw materials of Fe, Co, Cr, Ni, Mo and C (graphite) before charging; the vacuum degree in the melting period is kept at 1.0Pa, the vacuum degree in the refining period is kept at 15Pa, the refining temperature is 1510 ℃, and the holding time is 35min after the refining is finished.
d. Preparing high-entropy alloy powder: preparing high-entropy alloy powder by adopting a gas atomization method; the atomizing medium is N2The atomizing nozzle is designed in a circular seam mode, the aperture is 2mm, the diameter of the liquid guide pipe is 3.8mm, and the atomizing airflow pressure is 0.8 MPa;
e. pressing and forming: pressing the high-entropy alloy powder into a flat thin cylindrical pressed blank by adopting a warm compaction process, wherein the pressure is 650MPa, the holding time is 3.5min, and the pressing temperature is 150 ℃;
f. and (3) sintering: sintering the pressed blank by using a vacuum sintering furnace to form, wherein the sintering temperature is 1135 ℃;
g. hot forging: directly forging the pressed blank into a flexible wheel blank after sintering by adopting a hot forging process, and performing hot die forging at the die temperature of 920 ℃ and the strain rate of 0.01m/s, and performing air cooling on the blank after the hot forging;
h. high-temperature annealing: keeping the temperature of the flexible gear blank in a high-temperature annealing furnace at 600 ℃ for 90min, and then discharging the flexible gear blank out of the furnace for air cooling;
i. cryogenic treatment: carrying out cryogenic treatment on the annealed flexible gear blank, and carrying out cryogenic treatment in a liquid nitrogen box at the temperature of minus 142 ℃ for 22min and then taking out of the box for rewarming;
j. machining and forming: machining the soft gear blank subjected to the cryogenic treatment into a soft gear;
k. shot peening: shot peening is carried out on the machined flexible gear, the diameter of a shot is 0.18mm, the material of the shot is ZG30, the distance between spray guns is 120mm, the spraying angle is 90 degrees, the shot peening pressure is 0.6MPa, and the spraying time is 20 s. The surface tensile stress before shot blasting is 380MPa, and the surface compressive stress after shot blasting is 530 MPa.
Example 4
A method for processing a flexible gear comprises the following steps:
a. screening the types of the high-entropy alloys, and selecting the high-entropy alloys with FCC type single-phase solid solution structures as flexible gear materials;
b. designing chemical components of the high-entropy alloy: the high-entropy alloy is FeCoCrNiMo0.2C0.1Wherein the mol ratios of Fe, Co, Cr and Ni are 24.925%, the mol ratio of Mo is 0.2% and the mol ratio of C is 0.1%;
c. smelting a high-entropy alloy: smelting high-entropy alloy by using a vacuum induction furnace, and carrying out rust removal, dust removal and drying treatment on the surfaces of raw materials of Fe, Co, Cr, Ni, Mo and C (graphite) before charging; the vacuum degree in the melting period is kept at 2Pa, the vacuum degree in the refining period is kept at 20Pa, the refining temperature is 1520 ℃, and the holding time is 45min after the refining is finished;
d. preparing high-entropy alloy powder: preparing high-entropy alloy powder by adopting a gas atomization method; the atomizing medium is N2The atomizing nozzle is designed in a circular seam mode, the aperture is 2mm, the diameter of the liquid guide pipe is 3.8mm, and the atomizing airflow pressure is 0.8 MPa;
e. pressing and forming: pressing the high-entropy alloy powder into a flat thin cylindrical pressed blank by adopting a warm compaction process, wherein the pressure is 680MPa, the holding time is 4min, and the pressing temperature is 152 ℃;
f. and (3) sintering: sintering the pressed blank by using a vacuum sintering furnace at 1145 ℃;
g. hot forging: directly forging the pressed blank into a flexible wheel blank after sintering by adopting a hot forging process, and performing hot die forging at the die temperature of 920 ℃ and the strain rate of 0.01m/s, and performing air cooling on the blank after the hot forging;
h. high-temperature annealing: keeping the temperature of the flexible gear blank in a high-temperature annealing furnace at 598 ℃ for 92min, and then discharging the flexible gear blank out of the furnace for air cooling;
i. cryogenic treatment: carrying out cryogenic treatment on the annealed flexible gear blank, and carrying out cryogenic treatment in a liquid nitrogen box at the temperature of minus 146 ℃ for 26min and then taking out the blank from the box for rewarming;
j. machining and forming: machining the soft gear blank subjected to the cryogenic treatment into a soft gear;
k. shot peening: shot peening is carried out on the machined flexible gear, the diameter of a shot is 0.18mm, the material of the shot is ZG30, the distance between spray guns is 120mm, the spraying angle is 90 degrees, the shot peening pressure is 0.6MPa, and the spraying time is 20 s. The surface tensile stress before shot blasting is 420MPa, and the surface compressive stress after shot blasting is 560 MPa.
Comparative examples 1 to 4
The material selection and heat treatment specifications for the flexspline are shown in table 2.
The process route is as follows: forging, normalizing, tempering, machining and shot peening. Wherein the forging adopts a cross upsetting-drawing forging process.
Comparative example 5
A method for processing a flexible gear, which is different from embodiment 3 in that: in step f, the sintering temperature is 1000 ℃.
Comparative example 6
A method for processing a flexible gear, which is different from embodiment 3 in that: in step f, the sintering temperature was 1250 ℃.
Comparative example 7
A method for processing a flexible gear, which is different from the method of embodiment 4 in that: in the step i, the subzero treatment is carried out for subzero treatment for 10min in a liquid nitrogen box with the temperature of minus 120 ℃, and then the temperature is recovered after the subzero treatment is carried out.
Performance testing
1. And (4) detecting the grain size of the flexible gear by referring to a GB/T6394 and 2017 metal average grain size determination method.
2. Reference GB/T228.1-2010 metallic Material tensile test part 1: the room temperature test method detects the tensile strength, yield strength, elongation after fracture and product of strength and elongation of the flexible gear.
The results of the experiment are shown in Table 3.
As can be seen from Table 3, the average grain size of the flexspline prepared by the methods of examples 1 to 4 is 3.4 to 3.8 μm, the grain size reaches 13 grade or more, the tensile strength is 1215 to 1236MPa, the yield strength is 922 to 948MPa, the elongation is greater than 30%, and the product of strength and elongation is 38316 to 38880 MPa%. Experimental results show that the average grain size of the flexible gear prepared by the method of the embodiment 1-4 can be thinned to 3-4 mu m, the tensile strength and the yield strength are obviously improved, particularly the product of strength and elongation is greatly improved, the flexible gear has higher mechanical property and transmission property due to the parameters, and the service life of the harmonic reducer is obviously prolonged.
The comparison examples 1-4 are flexible gears prepared from medium-carbon low-alloy steel, and as can be seen from Table 3, the average grain size of the flexible gear is 8.5-13.6 microns, the grain size is 9.5-11 grades, the tensile strength is 1100-1180 MPa, the yield strength is 840-935 MPa, the elongation is 10-14%, and the product of strength and elongation is 11000-16520. Experimental results show that the flexible gear prepared from the medium-carbon low-alloy steel is far inferior to those prepared in the embodiments 1-4 of the application in terms of grain size, tensile strength, yield strength, elongation after fracture and product of strength and elongation.
Comparative examples 5 and 6 are different from example 3 in the sintering temperature. As can be seen from Table 3, the sintering temperature is reduced, the porosity and the density of the green compact are increased and reduced due to under-burning, and the pores are difficult to completely eliminate in the subsequent forging process, so that the mechanical property is greatly reduced, the tensile strength is reduced by 201 MPa, the yield strength is reduced by 118 MPa, the elongation is reduced by 9.4%, and the product of strength and elongation is reduced by 15960 MPa. The sintering temperature is increased, the crystal boundary has overburning defects, the mechanical property is greatly reduced, the tensile strength is reduced by 248Mpa, the yield strength is reduced by 208Mpa, the elongation is reduced by 12.5%, and the product of strength and elongation is reduced by 20038 MPa. The experimental results show that the sintering temperature has no obvious influence on the grain size of the flexible gear, but has great influence on the tensile strength, the yield strength, the elongation after fracture and the product of strength and elongation of the flexible gear. Therefore, the sintering temperature is controlled to be 1100-1150 ℃ in the flexible gear machining process, and the flexible gear has better mechanical property and transmission performance.
Comparative example 7 is different from example 4 in the temperature and time of the cryogenic treatment. As can be seen from Table 3, the mechanical properties of the flexible gear obtained by cryogenic cooling in a liquid nitrogen tank at-120 ℃ for 10min and then re-warming are also reduced, and compared with example 4, the tensile strength is reduced by 105MPa, the yield strength is reduced by 80MPa, the elongation is reduced by 5.5%, and the product of strength and elongation is reduced by 9465 MPa. The experimental result shows that the temperature and the time of the subzero treatment influence the tensile strength, the yield strength, the elongation after fracture and the product of strength and elongation of the flexible gear, and the annealed flexible gear blank is subjected to the subzero treatment, so that the stability of a microstructure can be further improved, and the strength and the plasticity are also further improved.
The embodiments of the present invention are preferred embodiments of the present application, and the technical principle and technical solution obtained by substituting or converting equivalents thereof should be covered by the scope of the present application.
Claims (10)
1. A high entropy alloy for use in the manufacture of a flexspline, wherein: the high-entropy alloy for manufacturing the flexible gear is a high-entropy alloy with an FCC single-phase solid solution structure.
2. A method according to claim 1The high-entropy alloy for manufacturing the flexible gear is characterized in that: the high-entropy alloy is FeCoCrNiMo0.2C0.1Wherein Fe, Co, Cr and Ni are equal atomic ratio, Mo and C are atomic percentage of 0.2% and 0.1% respectively.
3. A method for processing a flexible gear is characterized in that: the method comprises the following steps:
a. screening the types of the high-entropy alloys;
b. designing chemical components of the high-entropy alloy: the high-entropy alloy chemical composition in claim 2 is adopted;
c. smelting a high-entropy alloy: smelting a raw material of the high-entropy alloy;
d. preparing high-entropy alloy powder: preparing the smelted high-entropy alloy into powder;
e. pressing and forming: pressing the high-entropy alloy powder into a green compact;
f. and (3) sintering: sintering and forming the pressed compact;
g. hot forging: forging the sintered compact into a flexible gear blank;
h. high-temperature annealing: annealing the flexspline blank at high temperature;
i. cryogenic treatment: carrying out cryogenic treatment on the flexible gear blank subjected to high-temperature annealing;
j. machining and forming: machining the soft gear blank subjected to the cryogenic treatment into a soft gear;
k. shot peening: and performing shot peening on the machined flexible gear.
4. The method for manufacturing a flexible gear according to claim 3, wherein: in the step C, smelting the high-entropy alloy by using a vacuum induction furnace, and carrying out rust removal, dust removal and drying treatment on the surfaces of the raw materials of Fe, Co, Cr, Ni, Mo and C before charging; the vacuum degree in the melting period is kept at 0.7-5 Pa, the vacuum degree in the refining period is kept at 5-30 Pa, the refining temperature is 1500-1530 ℃, and the time is kept for 30-50 min after refining is finished.
5. The method for manufacturing a flexible gear according to claim 3, wherein: in the step d, preparing the high-entropy alloy powder by adopting a gas atomization method.
6. The method for manufacturing a flexible gear according to claim 3, wherein: and e, pressing the high-entropy alloy powder into a flat thin cylindrical pressed blank by adopting a warm-pressing forming process, wherein the pressure is 600-700 MPa, the pressing time is 3-4 min, and the pressing temperature is 150 +/-5 ℃.
7. The method for manufacturing a flexible gear according to claim 3, wherein: and f, sintering and forming the pressed compact by adopting a vacuum sintering furnace, wherein the sintering temperature is 1100-1150 ℃.
8. The method for manufacturing a flexible gear according to claim 3, wherein: and step g, directly forging the pressed compact into a flexible gear blank after sintering by adopting a hot forging process.
9. The method for manufacturing a flexible gear according to claim 3, wherein: and h, keeping the temperature of the flexspline blank at 595-605 ℃ in a high-temperature annealing furnace for 85-95 min, and then discharging the flexspline blank out of the furnace for air cooling.
10. The method for manufacturing a flexible gear according to claim 3, wherein: and i, carrying out cryogenic treatment on the annealed flexible gear blank, and carrying out cryogenic treatment in a liquid nitrogen box at the temperature of-150 to-140 ℃ for 20 to 30min, and then taking out the flexible gear blank from the box for rewarming.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010789581.7A CN111979465B (en) | 2020-08-07 | 2020-08-07 | High-entropy alloy for manufacturing flexible gear and processing method of flexible gear |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010789581.7A CN111979465B (en) | 2020-08-07 | 2020-08-07 | High-entropy alloy for manufacturing flexible gear and processing method of flexible gear |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN111979465A true CN111979465A (en) | 2020-11-24 |
| CN111979465B CN111979465B (en) | 2021-09-17 |
Family
ID=73445735
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202010789581.7A Active CN111979465B (en) | 2020-08-07 | 2020-08-07 | High-entropy alloy for manufacturing flexible gear and processing method of flexible gear |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN111979465B (en) |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112853190A (en) * | 2021-01-05 | 2021-05-28 | 中国矿业大学 | High-entropy cast iron and preparation method thereof |
| CN113427021A (en) * | 2021-06-28 | 2021-09-24 | 哈尔滨工业大学 | Cryogenic treatment method for additive manufacturing high-entropy alloy |
| CN114107715A (en) * | 2021-11-30 | 2022-03-01 | 中国科学院兰州化学物理研究所 | FeCoCrNiMo-based high-entropy alloy composite material and preparation method and application thereof |
| CN115198162A (en) * | 2022-09-19 | 2022-10-18 | 太原理工大学 | Entropy alloy in high-toughness heterogeneous multi-phase core-shell organization structure and preparation method thereof |
| CN115925423A (en) * | 2022-11-21 | 2023-04-07 | 中国科学院兰州化学物理研究所 | High-performance single-phase self-lubricating high-entropy ceramic material and preparation method thereof |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP1498504A1 (en) * | 2003-07-16 | 2005-01-19 | Alstom Technology Ltd | Multinary aluminium based alloys and their use as thermal and corrosion protecting coating |
| CN101130844A (en) * | 2006-08-21 | 2008-02-27 | 清华大学 | High-temperature alloy with low content of cobalt and nickel |
| US20100132408A1 (en) * | 2008-12-01 | 2010-06-03 | Saint-Gobain Coating Solution | Coating for a device for forming glass products |
| CN108517451A (en) * | 2018-05-03 | 2018-09-11 | 河北工业大学 | A kind of high-strength tenacity high-entropy alloy and preparation method with gradient grain structure |
| CN109868405A (en) * | 2019-03-27 | 2019-06-11 | 上海工程技术大学 | High-entropy alloy CoCrFeMnNi and its powder by atomization method reparation technology |
-
2020
- 2020-08-07 CN CN202010789581.7A patent/CN111979465B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP1498504A1 (en) * | 2003-07-16 | 2005-01-19 | Alstom Technology Ltd | Multinary aluminium based alloys and their use as thermal and corrosion protecting coating |
| CN101130844A (en) * | 2006-08-21 | 2008-02-27 | 清华大学 | High-temperature alloy with low content of cobalt and nickel |
| US20100132408A1 (en) * | 2008-12-01 | 2010-06-03 | Saint-Gobain Coating Solution | Coating for a device for forming glass products |
| CN108517451A (en) * | 2018-05-03 | 2018-09-11 | 河北工业大学 | A kind of high-strength tenacity high-entropy alloy and preparation method with gradient grain structure |
| CN109868405A (en) * | 2019-03-27 | 2019-06-11 | 上海工程技术大学 | High-entropy alloy CoCrFeMnNi and its powder by atomization method reparation technology |
Non-Patent Citations (2)
| Title |
|---|
| HUANG TIANDANG 等: "Effect of carbon addition on the microstructure and mechanical properties of CoCrFeNi high entropy alloy", 《SCIENCE CHINA TECHNOLOGICAL SCIENCES》 * |
| W.P.LI 等: "Fracture mechanisms of a Mo alloyed CoCrFeNi high entropy alloy: In-situ SEM investigation", 《MATERIALS SCIENCE AND ENGINEERING: A》 * |
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112853190A (en) * | 2021-01-05 | 2021-05-28 | 中国矿业大学 | High-entropy cast iron and preparation method thereof |
| CN113427021A (en) * | 2021-06-28 | 2021-09-24 | 哈尔滨工业大学 | Cryogenic treatment method for additive manufacturing high-entropy alloy |
| CN114107715A (en) * | 2021-11-30 | 2022-03-01 | 中国科学院兰州化学物理研究所 | FeCoCrNiMo-based high-entropy alloy composite material and preparation method and application thereof |
| CN114107715B (en) * | 2021-11-30 | 2022-05-13 | 中国科学院兰州化学物理研究所 | FeCoCrNiMo-based high-entropy alloy composite material and preparation method and application thereof |
| CN115198162A (en) * | 2022-09-19 | 2022-10-18 | 太原理工大学 | Entropy alloy in high-toughness heterogeneous multi-phase core-shell organization structure and preparation method thereof |
| CN115925423A (en) * | 2022-11-21 | 2023-04-07 | 中国科学院兰州化学物理研究所 | High-performance single-phase self-lubricating high-entropy ceramic material and preparation method thereof |
| CN115925423B (en) * | 2022-11-21 | 2023-07-18 | 中国科学院兰州化学物理研究所 | High-performance single-phase self-lubricating high-entropy ceramic material and preparation method thereof |
Also Published As
| Publication number | Publication date |
|---|---|
| CN111979465B (en) | 2021-09-17 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN111979465B (en) | High-entropy alloy for manufacturing flexible gear and processing method of flexible gear | |
| CN102230131B (en) | 38CrMoAl steel and preparation method thereof | |
| CN103602920B (en) | A kind of method of manufacturing technology of bearing steel and anti-friction bearing | |
| CN102560249A (en) | Formula and process for powder metallurgy | |
| CN112222413B (en) | Cold rolling composite laser additive manufacturing process method of gradient structure high-entropy alloy | |
| CN107532226A (en) | Steel, product and its manufacture method made of the steel | |
| US20200047254A1 (en) | Method for Manufacturing Iron-based Powder Metallurgical Parts | |
| CN113136531B (en) | Powder metallurgy stainless steel | |
| CN105312585A (en) | Powder forging method for forklift gearbox gear | |
| CN114318168B (en) | High-strength high-toughness carbonitriding steel and preparation method thereof | |
| CN105112782A (en) | Low-temperature ferrite LT-FH40 steel plate applied to hot-rolled ships and production method thereof | |
| CN104561657A (en) | Titanium-aluminium alloy material and preparation technology thereof | |
| CN102367554A (en) | High-performance quenched and tempered steel plate used in engineering machinery, and production technology thereof | |
| CN115369332A (en) | Maraging ultrahigh-strength steel and preparation method thereof | |
| CN107619997A (en) | A kind of wind-powered electricity generation super-thick steel plate and its production method | |
| CN109371336A (en) | The preparation method of ultra-high strength and toughness two-phase laser forming fe-based alloy powder and preparation method thereof, ultra-high strength and toughness shaping layer | |
| CN105983698A (en) | Powder forging method for forklift hub bearing | |
| CN110541112B (en) | Manufacturing method for improving toughness of large nuclear power SA508-3 connecting pipe forging | |
| CN105983691A (en) | Powder forging method for forklift synchronizer gear ring | |
| CN112222410A (en) | Preparation process of oil pump driving gear based on powder metallurgy press forming | |
| CN114535606B (en) | Oxide dispersion strengthening alloy and preparation method and application thereof | |
| CN106498304B (en) | A kind of corrosion resisting bearing and preparation method thereof | |
| CN114210981A (en) | Preparation method of titanium steel composite part | |
| CN112662981A (en) | High-hardness coating wear-resistant ball and preparation method thereof | |
| CN114277311B (en) | Steel material for crank shaft, preparation method and application |
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 | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |