CN110396582B - Metal component pore wall surface nanocrystallization device - Google Patents
Metal component pore wall surface nanocrystallization device Download PDFInfo
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- CN110396582B CN110396582B CN201910747445.9A CN201910747445A CN110396582B CN 110396582 B CN110396582 B CN 110396582B CN 201910747445 A CN201910747445 A CN 201910747445A CN 110396582 B CN110396582 B CN 110396582B
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- hole wall
- metal component
- impactor
- sleeve
- oil cylinder
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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
- C21D7/00—Modifying the physical properties of iron or steel by deformation
- C21D7/02—Modifying the physical properties of iron or steel by deformation by cold working
- C21D7/04—Modifying the physical properties of iron or steel by deformation by cold working of the surface
Abstract
The invention relates to a metal component hole wall surface nanocrystallization device, which is characterized in that: the ultrasonic energy conversion system comprises an ultrasonic energy conversion system and a metal component hole wall impactor; the ultrasonic energy conversion system is in driving connection with the metal component hole wall impactor, so that the metal component hole wall impactor can move in a radial direction perpendicular to the direction of the hole wall of the metal component to be processed, and the ultrasonic energy conversion system is reliable in movement, simple in structure, easy to manufacture and low in cost; the oil pressure in the oil cylinder is controlled by a hydraulic pump, and then the normal pressure of the tungsten carbide ball head on the impact rod pressing the surface of the hole wall of the metal component is controlled by a piston rod; the hole wall impactor of the metal component can be inserted into holes with any angle and any aperture to strengthen the surface of the hole wall, so that the energy consumption is low, and the environment is not polluted; the sleeve, the piston rod and the hole wall impactor of the metal component are of a matched modular structure, have strong universality, can adapt to surface treatment of inclined holes of the metal component in different apertures and different directions, have wide application range and are suitable for popularization and use.
Description
Technical Field
The invention relates to the field of metal surface engineering, in particular to a metal component hole wall surface nanocrystallization device.
Background
In mechanical structures in the fields of aviation, aerospace, high-speed rail, and the like, high-strength steel is used in large quantities. Although high strength steel has high strength, it has a higher stress concentration sensitivity. Holes are often made in the components due to the mechanical connection requirements. The holes are stress concentration parts of the whole component, and the component is always subjected to fatigue failure from the hole position, so that the whole component is scrapped. In other words, the fatigue life of the hole often determines the service life of the entire component. Therefore, the surface of the hole wall is strengthened, the mechanical property of the perforated member can be effectively improved, and the service life of the member is prolonged.
At present, mechanical shot blasting and laser impact strengthening treatment are adopted in most of hole wall strengthening processes at home and abroad. Mechanical shot blasting is a traditional metal material surface strengthening method, a reflecting device with a cone angle is required to be arranged in a hole for strengthening the hole wall, shot blasting is sprayed on the reflecting device, and shot is collided with the inner wall of the hole, so that the strengthening effect is achieved. The laser impact strengthening of the hole wall is to place an energy absorption rod in a proper position in the hole, and the energy absorption rod is induced by the laser to generate plasma explosion and generate impact waves so as to strengthen the inner wall of the small hole, but the effect of the method is to be further confirmed.
Experimental research shows that the overall performance of the material can be improved by optimizing the surface performance as long as the nano-structure surface layer with a certain thickness is prepared on the surface of the material, namely the surface nanocrystallization is realized. At the present stage, an important method for realizing the nanocrystallization of the material surface is a surface mechanical treatment method, which is mainly characterized in that an external load is repeatedly applied to the surface of the material in different directions, so that crystal grains on the surface of the material are gradually refined to a nanometer level through strong plastic deformation in different directions, thereby enhancing the surface mechanical properties of the material, such as hardness, frictional wear and the like, and improving the tensile strength, fatigue strength and corrosion resistance of the material. How to utilize the surface mechanical treatment method to realize the nanometer treatment of the pore wall with small pore diameter becomes an important direction for the research of the field of metal surface engineering.
Disclosure of Invention
The invention aims to provide a metal component hole wall surface nanocrystallization device, which can solve the problem that the hole diameter of the surface of the hole wall of a metal component is greatly restricted by common mechanical shot blasting and laser impact strengthening.
In order to solve the technical problems, the technical scheme of the invention is as follows:
a metal component hole wall surface nanocrystallization device comprises an ultrasonic transduction system and a metal component hole wall impactor; the ultrasonic energy conversion system is in driving connection with the metal component hole wall impactor;
the ultrasonic energy conversion system comprises an oil cylinder, a hydraulic pump, a piezoelectric ceramic stack, a power amplifier and a signal generator; a piston is arranged in the oil cylinder; the hydraulic pump is connected with the piston and used for driving the piston to reciprocate along the inner wall of the oil cylinder; one end of the piezoelectric ceramic stack is connected to the piston, and the other end of the piezoelectric ceramic stack is connected with a piston rod; the signal generator and the power amplifier are connected in series and then connected with the piezoelectric ceramic stack through a lead;
the end part of the piston rod extending out of the oil cylinder is of a prismatic table-shaped structure; a sleeve for accommodating a piston rod to penetrate through is arranged at the end part of the oil cylinder, and the piston rod moves back and forth along the inner wall of the sleeve; one end of the sleeve, which is far away from the oil cylinder, is provided with a plurality of through holes along the radial direction, and the through holes are used for accommodating the hole wall impactors of the metal components; the metal component hole wall impactor is provided with a plurality of through holes which are perpendicular to the axial direction of the sleeve and penetrate through the sleeve and are used for accommodating the metal component hole wall impactor, the end part of the metal component hole wall impactor, which is arranged in the sleeve, is of an inclined surface structure, and the end part and the inclined surface of the prismatic table structure at the end part of the piston rod, which moves along the axial direction, are matched in a wedge shape to realize the radial movement of the metal component hole wall impactor along the sleeve.
Preferably, the output end of the hydraulic pump is provided with a liquid outlet pipeline and a liquid return pipeline; the liquid outlet pipeline and the liquid return pipeline are respectively connected to the oil cylinder and form a hydraulic loop between the oil cylinder and the liquid outlet pipeline; and an oil pressure gauge is arranged on the liquid outlet pipeline and used for displaying the oil pressure in the oil cylinder.
Preferably, the sleeve is of a cylindrical structure with an opening at one end and a closed end, the opening end of the sleeve is provided with a flange, and the flange is locked at one end of the oil cylinder through a bolt; the side edge of the closed end of the sleeve is perpendicular to the axis direction, and the metal member hole wall impactors arranged in the through hole in a penetrating mode are distributed along the circumferential direction of the end part of the closed end of the sleeve at equal angles.
Preferably, the metal member hole wall impactor comprises a striking rod and a striking ball head; the impact ball head is arranged at one end of the impact rod and is positioned outside the through hole on the sleeve; the impact ball head is a tungsten carbide ball head.
Preferably, the signal generator is configured to generate an ultrahigh frequency alternating voltage signal, and the ultrahigh frequency alternating voltage signal is amplified by the power amplifier and then applied to the piezoelectric ceramic stack to generate ultrasonic vibration in the piezoelectric ceramic stack, so as to drive the piston rod to reciprocate at an ultrasonic frequency, thereby driving the metal member hole wall impactor to impact the hole wall surface at the ultrasonic frequency.
Preferably, the sleeve, the piston rod and the metal member hole wall impactor are of matched modular structures, and the sleeve, the piston rod and the metal member hole wall impactor with different diameters can be selected according to the inner diameter of the metal member hole wall.
Compared with the prior art, the invention has the advantages that:
1) according to the invention, the hole wall impactor of the metal component is adopted to convert axial motion along the hole into radial motion, so that the device is reliable in motion, simple in structure, easy to manufacture and low in cost; the oil pressure in the oil cylinder is controlled by a hydraulic pump, and then the normal pressure of the tungsten carbide ball head on the impact rod pressing the surface of the hole wall of the metal component is controlled by a piston rod; the device has simple and practical installation mode, and can extend the hole wall impactor of the metal component into holes with any angle to strengthen the surface of the hole wall; the wall of the hole of the metal component is subjected to surface nanocrystallization treatment, so that the energy consumption is low, no residue is generated, and no pollution is caused to the environment.
2) The sleeve, the piston rod and the metal component hole wall impactor are of a matched modular structure, have strong universality, can adapt to surface treatment of metal components with different apertures and inclined holes in different directions, have wide application range and are suitable for popularization and use.
Drawings
Fig. 1 is a schematic structural view of a metal member hole wall surface nanocrystallization apparatus according to the present invention.
FIG. 2 is a side view of a metallic component hole wall impactor of a metallic component hole wall surface nano-microphone device according to the present invention.
As shown in the figure: 1. an ultrasonic transduction system; 11. an oil cylinder; 12. a hydraulic pump; 121. a liquid outlet pipeline; 122. a liquid inlet pipeline; 13. a piezoelectric ceramic stack; 14. a power amplifier; 15. a signal generator; 16. a piston; 17. a piston rod; 18. a sleeve; 2. a metal component hole wall impactor; 21. a striker bar; 22. the ball head is impacted.
Detailed Description
The following examples are presented to enable one of ordinary skill in the art to more fully understand the present invention and are not intended to limit the scope of the embodiments described herein.
The metal component hole wall surface nanocrystallization device shown in fig. 1 and fig. 2 comprises an ultrasonic transduction system 1 and a metal component hole wall impactor 2; the ultrasonic energy conversion system 1 is in driving connection with the metal component hole wall impactor 2 and is used for driving the metal component hole wall impactor 2 to move relative to the hole wall of the metal component to be subjected to nanocrystallization.
The ultrasonic energy conversion system 1 comprises an oil cylinder 11, a hydraulic pump 12, a piezoelectric ceramic stack 13, a power amplifier 14 and a signal generator 15; a piston 16 is arranged in the oil cylinder 11; the output end of the hydraulic pump 12 is provided with a liquid outlet pipeline 121 and a liquid return pipeline 122, and the liquid outlet pipeline 121 is provided with an oil pressure gauge; the liquid outlet pipeline 121 and the liquid return pipeline 122 are respectively connected to the oil cylinder 11 and the oil cylinder 11 to form a hydraulic loop; the hydraulic pump 12 is connected with the oil cylinder 11 through a liquid outlet pipeline 121 and a liquid return pipeline 122, the hydraulic pump 12 adjusts the oil pressure in the oil cylinder 11 by injecting or discharging oil into the oil cylinder 11 and pushes a piston 16 arranged in the oil cylinder to reciprocate along the inner wall of the oil cylinder 11, and the oil pressure in the oil cylinder 11 can be displayed by an oil pressure gauge; one end of the piezoelectric ceramic stack 13 is connected to one surface of the piston 16 far away from the hydraulic pump 12, and the other end of the piezoelectric ceramic stack 13 is connected with a piston rod 17; the signal generator 15 and the power amplifier 14 are connected in series and then connected with the piezoelectric ceramic stack 13 through a lead.
The end part of the piston rod 17 extending out of the oil cylinder 11 is of a frustum pyramid structure; the end part of the oil cylinder 11 is provided with a sleeve 18 for accommodating a piston rod 17 to pass through, and the piston rod 17 can reciprocate along the inner wall of the sleeve 18; one end of the sleeve 18 far away from the oil cylinder 11 is provided with a plurality of through holes for accommodating the metal component hole wall impacters 2 along the radial direction; the metal component hole wall impactors 2 are provided with a plurality of metal component hole wall impactors 2, the number of the metal component hole wall impactors 2 is the same as that of the through holes, the metal component hole wall impactors 2 penetrate through the through holes in the sleeve 18 in a direction perpendicular to the axial direction of the sleeve 18, and each metal component hole wall impactors 2 comprises an impact rod 21 and an impact ball head 22; the impact ball head 22 is arranged at one end of the impact rod 21 and is positioned outside the through hole on the sleeve 18; the other end of the impact rod 21 is in an inclined surface structure and is matched with the inclined surface of the prismatic table structure at the end part of the piston rod 17 in a wedge shape to generate relative motion, and the axial motion of the piston rod 17 is converted into the radial motion of the metal component hole wall impactor 2 through the relative motion; the impact ball 22 is a tungsten carbide ball. The sleeve 18 is of a cylindrical structure with one open end and one closed end, the open end of the sleeve 18 is provided with a flange, and the flange is locked at one end of the oil cylinder 11 through a bolt; the side of the upper closed end of the sleeve 18 is perpendicular to the axis direction, and the through hole for accommodating the metal member hole wall impactor 2 and the metal member hole wall impactor 2 penetrating through the through hole are distributed at equal angles along the circumferential direction of the end part of the closed end of the sleeve 18, so that the uniformity of impact of the metal member hole wall impactor 2 on the hole wall is ensured.
The sleeve 18, the piston rod 17 and the metal component hole wall impactor 2 are of matched modular structures, and the sleeve 18, the piston rod 17 and the metal component hole wall impactor 2 with different diameters can be selected according to the inner diameter of the metal component hole wall.
The signal generator 15 generates an ultrahigh frequency alternating voltage signal, the ultrahigh frequency alternating voltage signal is amplified by the power amplifier 14 and then applied to the piezoelectric ceramic stack 13, the piezoelectric ceramic stack 13 generates ultrasonic vibration, and the piston rod 17 is driven to reciprocate at ultrasonic frequency, so that the metal component hole wall impactor 2 impacts the hole wall surface at the ultrasonic frequency.
The invention discloses a metal component pore wall surface nanocrystallization device, which has the working principle that: the ultrasonic transducer system 1 is connected with the metal component hole wall impactor 2, wherein the piezoelectric ceramic stack 13 is connected with a tapered piston rod 17, and a sleeve 18 is fixed with the oil cylinder 11. In the metal member hole wall impactor 2, a sleeve 18 is provided with a pair of holes along the radial direction so as to arrange a striking rod 21 with a tungsten carbide ball head. These striking rods 21 and the conical surface contact of the piston rod 17 to produce a relative movement, by which the axial movement of the piston rod 17 is converted into a radial movement of the striking rods 21. Based on the piezoelectric effect, under the action of an external alternating voltage, the piezoelectric ceramic stack axially vibrates. The response frequency of the piezoelectric ceramic stack 13 can reach 20kHz, the nominal displacement can reach 60 mu m, and the maximum thrust force is 20000N. When the surface nanocrystallization treatment is carried out on the hole wall of the metal component, the hole wall impactor 2 of the metal component is inserted into the hole, then the hydraulic pump 12 is started to inject oil into the oil cylinder 11, the oil pressure in the oil cylinder 11 is set according to the index of an oil pressure gauge, and at the moment, the tungsten carbide ball on the impact rod 21 is pressed on the surface of the hole wall with set constant force. The ultrahigh frequency alternating voltage signal generated by the signal generator 15 is amplified by the power amplifier 14 and then applied to the piezoelectric ceramic stack 13 to generate ultrasonic vibration, so as to drive the piston rod 17 and the impact rod 21 to impact the surface of the hole wall at ultrasonic frequency. The oil cylinder 11 moves slightly or rotates when the ultrasonic impact is carried out, and then the tungsten carbide ball in the impact rod 21 not only impacts but also rolls the surface of the hole wall, so that the crystal grains on the surface of the hole wall material are gradually thinned to the nanometer level through strong plastic deformation in different directions, and the nanocrystallization of the surface of the hole wall is realized. If the metal component hole to be processed by nano treatment is an inclined hole, the oil cylinder 11 can rotate to drive the sleeve 18 to be consistent with the axis of the inclined hole, so that the ultrasonic impact of the metal component hole wall impactor 2 on the metal component hole wall is realized.
It will be understood by those skilled in the art that the present invention is not limited to the embodiments described above, which are described in the specification and illustrated only to illustrate the principle of the present invention, but that various changes and modifications may be made therein without departing from the spirit and scope of the present invention, which fall within the scope of the invention as claimed. The scope of the invention is defined by the appended claims and equivalents thereof.
Claims (6)
1. A metal component pore wall surface nanocrystallization device is characterized in that: the ultrasonic energy conversion system comprises an ultrasonic energy conversion system and a metal component hole wall impactor; the ultrasonic energy conversion system is in driving connection with the metal component hole wall impactor;
the ultrasonic energy conversion system comprises an oil cylinder, a hydraulic pump, a piezoelectric ceramic stack, a power amplifier and a signal generator; a piston is arranged in the oil cylinder; the hydraulic pump is connected to the oil cylinder and drives the piston to reciprocate along the inner wall of the oil cylinder; one end of the piezoelectric ceramic stack is connected to the piston, and the other end of the piezoelectric ceramic stack is connected with a piston rod; the signal generator and the power amplifier are connected in series and then connected with the piezoelectric ceramic stack through a lead;
the end part of the piston rod extending out of the oil cylinder is of a prismatic table-shaped structure; a sleeve for accommodating a piston rod to penetrate through is arranged at the end part of the oil cylinder, and the piston rod can reciprocate along the inner wall of the sleeve; one end of the sleeve, which is far away from the oil cylinder, is provided with a plurality of through holes along the radial direction, and the through holes are used for accommodating the metal component hole wall impactors; the metal component hole wall impactor is provided with a plurality of through holes which are perpendicular to the axial direction of the sleeve and penetrate through the sleeve and are used for accommodating the metal component hole wall impactor, the end part of the metal component hole wall impactor, which is arranged in the sleeve, is of an inclined surface structure, and the end part of the metal component hole wall impactor and the inclined surface of the prismatic table structure at the end part of the piston rod, which moves along the axial direction, are matched in a wedge shape to realize the radial movement of the metal component hole wall impactor along the sleeve.
2. The apparatus as claimed in claim 1, wherein: the output end of the hydraulic pump is provided with a liquid outlet pipeline and a liquid return pipeline; the liquid outlet pipeline and the liquid return pipeline are respectively connected to the oil cylinder and form a hydraulic loop between the oil cylinder and the liquid outlet pipeline; and an oil pressure gauge is arranged on the liquid outlet pipeline and used for displaying the oil pressure in the oil cylinder.
3. The apparatus as claimed in claim 1, wherein: the sleeve is of a cylindrical structure with one open end and one closed end, the open end of the sleeve is provided with a flange, and the flange is locked at one end of the oil cylinder through a bolt; the side edge of the closed end of the sleeve is perpendicular to the axis direction, and the metal member hole wall impactors arranged in the through hole in a penetrating mode are distributed along the circumferential direction of the end part of the closed end of the sleeve at equal angles.
4. The apparatus as claimed in claim 1, wherein: the metal component hole wall impactor comprises an impact rod and an impact ball head; the impact ball head is arranged at one end of the impact rod and is positioned outside the through hole on the sleeve; the impact ball head is a tungsten carbide ball head.
5. The apparatus as claimed in claim 1, wherein: the signal generator is used for generating an ultrahigh frequency alternating voltage signal, the ultrahigh frequency alternating voltage signal is amplified by the power amplifier and then applied to the piezoelectric ceramic stack to enable the piezoelectric ceramic stack to generate ultrasonic vibration, and the piston rod is driven to reciprocate at ultrasonic frequency, so that the metal component hole wall impactor is driven to impact the hole wall surface at the ultrasonic frequency.
6. The apparatus as claimed in claim 1, wherein: the sleeve, the piston rod and the metal component hole wall impactor are of matched modular structures, and the sleeve, the piston rod and the metal component hole wall impactor with different diameters can be selected according to the inner diameter of the metal component hole wall.
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| CN201910747445.9A CN110396582B (en) | 2019-08-14 | 2019-08-14 | Metal component pore wall surface nanocrystallization device |
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| CN201910747445.9A CN110396582B (en) | 2019-08-14 | 2019-08-14 | Metal component pore wall surface nanocrystallization device |
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| CN110396582B true CN110396582B (en) | 2020-11-24 |
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Family Cites Families (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS611438A (en) * | 1984-06-14 | 1986-01-07 | Kobe Steel Ltd | Reinforcing method of transmission shaft having circular hole |
| CN100469900C (en) * | 2006-09-27 | 2009-03-18 | 江苏大学 | Technical hole wall intensifying method based on laser impaction wave and apparatus |
| CN101962706B (en) * | 2010-10-08 | 2012-04-18 | 中国航空工业集团公司北京航空材料研究院 | Compound strengthening method of small hole in ultrahigh strength steel part |
| CN101942546B (en) * | 2010-10-19 | 2012-08-15 | 江苏大学 | Method and device for laser shock processing of fastening holes |
| CN103447403A (en) * | 2013-09-18 | 2013-12-18 | 山东法因数控机械股份有限公司 | Hole extrusion enhancing device |
| CN105112645A (en) * | 2015-09-14 | 2015-12-02 | 南通大学 | Spiral-pressure type ultrasonic surface nanocrystallization device |
| CN105063340B (en) * | 2015-09-14 | 2017-07-04 | 南通大学 | Fluid pressure type ultrasonic surface nanocrystallization device |
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