CN115945776A - A device and method capable of realizing multiple laser shot peening under a rigid constrained layer - Google Patents

Abstract

The invention provides a device and method capable of realizing multiple laser shot peening under a rigid constrained layer, including a motion system, a laser shot peening strengthening system, a laser heating and heating system, a particle flow system, and a working tank. The workpiece to be processed is installed, and the working tank is connected with the particle flow system to form a closed loop, and the charged black paint particles are adsorbed on the surface of the workpiece to be processed through the particle flow system; the laser heating and heating system is used to make the charged black paint The particles form a black paint deposition layer on the surface of the workpiece to be processed; the laser shot peening strengthening system is used for laser shot blasting on the surface of the workpiece to be processed. The invention utilizes the characteristic that charged small particles are easy to adsorb on the metal surface, and adopts nanosecond pulse laser heating method to melt and deposit tiny black paint particles at designated positions, thereby realizing timely replenishment of the absorbing layer and accurate thickness of the absorbing layer control.

Description

A device and method capable of realizing multiple laser shot peening under a rigid constrained layer

technical field

The invention relates to the field of laser shock forming, in particular to a device and method capable of realizing multiple laser shot peening forming under a rigid constrained layer.

Background technique

Laser shot peening is a new method of flexible and precise moldless forming. It uses the high-energy laser beam to impact the sheet material point by point, and the impact of the vapor produced by laser ablation on the metal material causes the metal material to produce compression plastic deformation. Utilizing the plastic ductility and deformation characteristics of metal materials, small deformations can be accumulated to form large macroscopic deformations. Has been widely used in aerospace, space science, marine ships and other fields.

Theory and practice have proved that the confinement layer can greatly increase the pressure of the laser shock wave and prolong its duration by hindering the escape of vapors, so that better forming benefits can be obtained.

Common constrained layers are divided into liquid constrained layers, flexible constrained layers, and rigid constrained layers. Among them, since the rigid constrained layer does not deform, it can maintain the initial state of the high-pressure air mass for a long time, and then the vapor from the constrained layer and the workpiece Diffusion through gaps.

Although the rigid constrained layer has the best confinement effect on vapors, at present, the rigid constrained layer is usually not used in laser shot peening, because the following difficulties cannot be solved:

1. Laser shot peening produces colored vapors that will adhere to the surface of the rigid absorbing layer. If multiple impacts will prevent the laser beam from irradiating the surface of the metal workpiece, and cause irreparable damage to the constrained layer.

2. Since laser peening will produce pits, and the center of the workpiece will be depressed after forming, the gap between the rigid constrained layer and the absorbing layer is too large, which is not conducive to the restraint of vaporized substances, and will greatly reduce the magnitude and duration of the impact force.

3. If the absorbing layer is too thick, it is not conducive to the transmission of impact force to the surface of the workpiece. When the absorbing layer is too thin, the absorbing layer needs to be replaced if laser peening is performed many times, and the process is cumbersome.

Contents of the invention

Aiming at the deficiencies in the prior art, the present invention provides a device and method capable of realizing multiple laser shot peening under a rigid constrained layer, which utilizes the characteristic that small charged particles are easily adsorbed on the metal surface, and adopts nanosecond pulse The method of laser heating makes the tiny black paint particles melt and deposit at the designated position, so as to realize the timely replenishment of the absorbing layer and the precise control of the thickness of the absorbing layer. The femtosecond pulse laser is used for multiple shot peening, and the forming accuracy is extremely high; heating and heating The system combined with the high-speed flowing airflow can melt and remove the black paint impurities attached to the surface of the optical glass flexibly, without damaging the optical glass or affecting the benefits of the next laser peening.

The present invention achieves the above-mentioned technical purpose through the following technical means.

A device that can realize multiple laser shot peening under a rigid constrained layer, including a motion system, a laser shot peening strengthening system, a laser heating and heating system, a particle flow system and a working tank,

The workpiece to be processed is installed in the working tank, and the working tank and the particle flow system are connected to form a closed loop, and the charged black paint particles are adsorbed on the surface of the workpiece to be processed through the particle flow system; the laser heating system is used to make the Charged black paint particles form a black paint deposition layer on the surface of the workpiece to be processed; the laser shot peening strengthening system is used to perform laser shot blasting on the surface of the workpiece to be processed; the motion system is used to make the laser shot peening strengthening system, laser heating The heating system and the workpiece to be processed move.

Further, the particle flow system includes a housing, an electronic injector, an electronic storage chamber, a high-speed fan, a cooling rod, a particle pulverizer, a particle storage box, a pressure sensor probe and an air pump;

The closed channel of the housing is provided with a working tank, the housing above the working tank is provided with optical glass, and the closed channel is sequentially installed with a particle grinder, a particle storage box, a high-speed fan, and an electronic storage device according to the flow direction. cavity and the workpiece to be processed; black paint particles are stored in the particle storage box, and the refrigeration rod is used to cool the recovered vaporized black paint; the particle crusher is used to break the cooled black paint into black Paint particles; an air pump is provided at the outlet of the particle pulverizer to maintain pressure in the closed flow channel;

The upper half of one side wall of the particle storage box is a mesh structure, the lower half of the one side wall of the particle storage box is a closed boundary; the other side wall of the particle storage box is a double-layer baffle, and a layer of baffle It is a mesh baffle, and the other layer is a movable closed baffle; a movable platen mechanism is installed on the particle storage box, which is used to divide the particle storage box into a circulation area and a black paint particle area; the electronic The upper and lower sides of the storage cavity are net-like structures, and electron injectors are installed on the electronic storage cavity to generate free electrons inside the electronic storage cavity.

Further, the laser heating and heating system includes a nanosecond laser, a second reflector and a second focus mirror; the laser beam emitted by the nanosecond laser is reflected by the second reflector and then focused on the workpiece to be processed by the second focus mirror The surface is used to make the charged black paint particles form a black paint deposition layer on the surface of the workpiece to be processed; when the height of the black paint deposition layer increases, the laser beam is focused on the black paint by changing the focus position of the second focusing mirror On the black paint particle adsorption layer on the upper surface of the deposition layer; the laser shot peening strengthening system includes a femtosecond laser, a first reflector and a first focusing mirror; the laser beam emitted by the femtosecond laser is reflected by the first reflector Afterwards, it is focused to the upper surface of the black paint deposition layer by the first focusing mirror.

Further, the motion system includes a first slide rail, a first slide block, a second slide block, a second slide rail, a third slide block and a mobile platform, and the first slide block and the second slide block are respectively installed on the On a slide rail; the first slide block is connected with the first reflector, and the second slide block is connected with the second reflector; the third slide block is installed on the second slide rail; the third slide The block is connected with the second focusing mirror, and is used to change the focus position of the second focusing mirror; the workpiece to be processed is placed on the moving platform.

Further, it also includes a three-dimensional information collector, a pressure sensor and a displacement sensor, the three-dimensional information collector is aimed at the lower surface of the optical glass, and is used to capture whether there is black paint vapor attached to the lower surface of the optical glass; the displacement sensor is used to detect The thickness of the black paint deposition layer and the distance between the black paint deposition layer and the optical glass; the pressure sensor is used to detect the pressure in the closed flow channel.

A method capable of realizing multiple laser shot peening devices under a rigid constrained layer, comprising the following steps:

Fill the closed channel with high-pressure gas through the air pump, and close the air pump when the pressure sensor reaches the first set value;

By controlling the high-speed fan to start, the black paint particles in the particle storage box are circulated in the closed flow channel; after the black paint particles pass through the electronic storage chamber, the black paint particles are charged by the electronic injector; the charged black paint particles Adsorbed on the surface of the workpiece to be processed;

Control the movement of the second slider so that the light of the nanosecond laser is reflected by the second reflector and reaches the surface of the workpiece to be processed; the laser focus is used to align the black paint particle layer adsorbed on the surface of the workpiece to be processed to form a black paint deposition layer; when When it is determined by the displacement sensor that the thickness of the black paint deposition layer reaches the design value, the nanosecond laser is turned off;

Control the movement of the first slider so that the light of the femtosecond laser is reflected by the first reflector and reaches the surface of the black paint deposit layer; the particle storage box is divided into a circulation area and a black paint particle area by moving the pressure plate mechanism; The plate connects the flow area with the closed flow channel; the black paint deposit is laser peened by the laser generated by the femtosecond laser;

The three-dimensional information collector captures whether there is black paint vapor attached to the lower surface of the optical glass. When there is black paint vapor, the laser generated by the nanosecond laser is focused on the lower surface of the optical glass for laser cleaning; the wind speed of the high-speed fan is controlled. The air flow in the runner blows away the melted or vaporized black paint attachments.

Further, the following steps are also included:

During the laser peening process, the displacement sensor monitors the thickness of the black paint deposit in real time, and when the thickness of the black paint deposit is less than the second set value, the laser peening process is stopped, and the movable closed baffle is controlled to make the black paint The particle area is connected with the closed flow channel, and the charged black paint particles are adsorbed on the surface of the black paint deposition layer by controlling the high-speed fan to be started; the light of the nanosecond laser is controlled to be reflected by the second reflector to reach the surface of the black paint deposition layer; The laser focus is aimed at the black paint particle layer adsorbed on the surface of the black paint deposition layer, which is used to supplement the black paint deposition layer.

Further, control the focus point position of the nanosecond laser according to the monitoring value of the displacement sensor, so that the thickness of the black paint deposition layer is 1-100 μm; by controlling the mobile platform, the distance between the black paint deposition layer and the optical glass is 5-20 μm; The diameter of the particles in the particle storage box is within 1 μm; the black paint grinder crushes the cooled block black paint into particles with a diameter of less than 1 μm.

Further, the flow rate of electrons ejected by the electron injector is much greater than the instantaneous flow rate of the particles in the closed flow channel passing through the high-speed fan; when the nanosecond laser heats the black paint particles to form a black paint deposition layer, the flow rate of the high-speed fan is 1-10 mm/s , to control the downward movement of the movable closed baffle, which is used to increase the flow section;

When the femtosecond laser performs laser peening on the black paint deposition layer, the flow rate of the high-speed fan is 10-100mm/s, and the movable closed baffle is controlled to move up, so as to reduce the flow section;

When the laser generated by the nanosecond laser cleans the lower surface of the optical glass, the flow rate of the high-speed fan is 100-1000mm/s, and the movable closed baffle is controlled to move up to reduce the flow section.

Further, the nanosecond laser adopts a square spot, the side length of the spot is 0.1-1mm, the laser energy is 0.03-5mJ, and the laser pulse width is 5-10ns;

The femtosecond laser adopts a circular spot with a spot diameter of 3-5 mm, a laser energy of 3-15 mJ, and a laser pulse width of 300-500 fs.

The beneficial effects of the present invention are:

1. The present invention can realize the device and method of multiple laser shot peening under the rigid constrained layer. A layer of particle film can be formed on the surface of the deposition layer through the flowing fine charged black paint particles. Combined with nano-laser heating technology, the laser spray can be supplemented in time. The pits produced by the shot and the central depression produced by the deformation of the workpiece can be accurately repaired to avoid the attenuation of the impact effect caused by the change of the surface topography.

2. The present invention can realize the device and method of multiple laser shot peening under the rigid constrained layer, and the infrared range finder can detect the thickness of the black paint deposition layer and the distance from the rigid constrained layer in real time, effectively ensuring that the constrained layer is free from gasification Confinement effects and reduced attenuation of impact forces along sediment layers.

3. The present invention can realize the device and method of multiple laser shot peening under the rigid constrained layer. The three-dimensional information collector can detect the adhesion of vapors on the surface of the rigid constrained layer in real time, and the control system can be cleaned and removed in time, avoiding the impact of stains on the laser The absorption of energy improves the utilization rate of laser energy and reduces the damage of the rigid constrained layer, which can ensure that the effect of each laser peening is basically unchanged.

4. The present invention can realize the device and method of multiple laser shot peening under the rigid constrained layer. The black paint particles are gasified and condensed in the closed space for circulation, and the particle pulverizer can roll the condensed massive black paint into a Granularity required for repeated use.

5. The present invention can realize the device and method of multiple laser shot peening under the rigid constrained layer. During laser peening, the airflow flowing in the pores of the absorbing layer and the constrained layer can take away the black paint vapor, avoiding the formation of the black paint on the optical glass. Surface solidification affects the shot peening effect.

6. The present invention can realize the device and method of multiple laser shot peening forming under the rigid constrained layer. During the laser pulse process, the target surface temperature and pressure accumulate to form an unbalanced Knudsen layer. The pressure in the Knudsen layer is released rapidly, causing the overpressure to decay exponentially during the evolution of the shock wave. The attenuation of overpressure is due to the relatively low density and relatively high compressibility of air. Laser ablation products continuously compress the air to work, resulting in irreversible energy loss. The air pressure pump ensures that the initial environment of the laser shot peening area is a high pressure state, the density increases, and the compressibility decreases, which can increase the peak value of the Knudsen layer before the pressure is released, slow down the speed at which the gasification product squeezes the air, and thereby reduce the overpressure The attenuation speed, which improves the peak value and duration of the impact force, has a promotion effect on laser shot peening.

Description of drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings that need to be used in the description of the embodiments or the prior art. For some embodiments, it is obvious to those skilled in the art that other drawings can be obtained based on these drawings without any creative effort.

Fig. 1 is an assembly diagram of a device capable of realizing multiple laser shot peening under a rigid constrained layer according to the present invention.

Fig. 2 is a process flow chart of the processing method capable of realizing multiple laser shot peening under the rigid constrained layer according to the present invention.

In the picture:

1-first slide rail; 2-first slider; 3-second slider; 4-femtosecond laser; 5-first mirror; 6-second mirror; 7-nanosecond laser; 8-computer ;9-three-dimensional information collector; 10-first focusing mirror; 11-second focusing mirror; 12-second slide rail; 13-third slider; 14-optical glass; 15-displacement sensor; ;17-black paint particles; 18-motion controller; 19-black paint deposition layer; 20-workpiece to be processed; 21-moving platform; 22-electronic injector; 23-electronic storage cavity; High-speed fan; 26-refrigerating rod; 27-particle pulverizer; 28-particle storage box; 29-wind speed controller; 30-moving plate mechanism; 31-pressure sensor; 32-baffle controller; 33-air pressure pump.

Detailed ways

The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments, but the protection scope of the present invention is not limited thereto.

Embodiments of the present invention are described in detail below, examples of which are shown in the drawings, wherein the same or similar reference numerals designate the same or similar elements or elements having the same or similar functions throughout. The embodiments described below by referring to the figures are exemplary and are intended to explain the present invention and should not be construed as limiting the present invention.

In describing the present invention, it is to be understood that the terms "central", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "axial", The orientation or positional relationship indicated by "radial", "vertical", "horizontal", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present invention and simplifying the description , rather than indicating or implying that the device or element referred to must have a particular orientation, be constructed and operate in a particular orientation, and thus should not be construed as limiting the invention. In addition, the terms "first" and "second" are used for descriptive purposes only, and cannot be interpreted as indicating or implying relative importance or implicitly specifying the quantity of indicated technical features. Thus, a feature defined as "first" and "second" may explicitly or implicitly include one or more of these features. In the description of the present invention, "plurality" means two or more, unless otherwise specifically defined.

In the present invention, unless otherwise clearly specified and limited, terms such as "installation", "connection", "connection" and "fixation" should be understood in a broad sense, for example, it can be a fixed connection or a detachable connection , or integrally connected; it may be mechanically connected or electrically connected; it may be directly connected or indirectly connected through an intermediary, and it may be the internal communication of two components. Those of ordinary skill in the art can understand the specific meanings of the above terms in the present invention according to specific situations.

As shown in Figure 1, the device of the present invention that can realize multiple laser shot peening under a rigid constrained layer includes a motion system, a laser shot peening strengthening system, a laser heating and heating system, a particle flow system and a working tank. The workpiece 20 to be processed is installed in the working tank, and the working tank and the particle flow system are connected to form a closed loop, and the charged black paint particles 17 are adsorbed on the surface of the workpiece 20 to be processed through the particle flow system; the laser shot peening strengthening system and The laser heating and heating system is respectively located above the workpiece 20 to be processed, and the laser heating and heating system is used to make the charged black paint particles 17 form a black paint deposition layer 19 on the surface of the workpiece 20 to be processed; the laser shot peening strengthening system is used for Laser shot peening is performed on the surface of the workpiece 20 to be processed; the motion system is used to move the laser shot peening strengthening system, the laser heating system and the workpiece 20 to be processed. The invention utilizes the characteristic that charged small particles are easy to adsorb on the metal surface, and adopts nanosecond pulse laser heating method to melt and deposit tiny black paint particles at designated positions, thereby realizing timely replenishment of the absorbing layer and accurate thickness of the absorbing layer Control, using femtosecond pulse laser multiple shot peening forming, the forming accuracy is extremely high; the heating system combined with high-speed flowing air flow can melt and remove the black paint impurities attached to the surface of the optical glass, without damaging the optical glass and not affecting the next time Benefits of laser peening.

The particle flow system includes a housing 16, an electronic injector 22, an electronic storage chamber 23, a high-speed fan 25, a refrigeration rod 26, a particle pulverizer 27, a particle storage box 28, a pressure sensor probe 31 and an air pump 33; The closed channel of the body 16 is provided with a working tank, the housing above the working tank is provided with an optical glass 14, and the closed channel is sequentially installed with a particle grinder 27, a particle storage box 28, a high-speed fan 25, Electronic storage chamber 23 and workpiece 20 to be processed; black paint particles are stored in the particle storage box 28, and the cooling rod 26 is used to cool down the vaporized black paint recovered; the particle grinder 27 is used to cool down The black paint is broken into black paint particles; the outlet of the particle pulverizer 27 is provided with an air pump 33, which is used to maintain the pressure in the closed flow channel; the half part of the side wall surface of the particle storage box 28 is a mesh structure, The lower half of one side wall of the particle storage box 28 is a closed boundary; the other side wall of the particle storage box 28 is a double-layer baffle, one layer of baffle is a mesh baffle, and the other is a movable closed A baffle plate; a movable platen mechanism 30 is installed on the particle storage box 28, which is used to divide the particle storage box 28 into a circulation area and a black paint particle area; the upper and lower sides of the electronic storage chamber 23 are mesh structures, An electron injector 22 is installed on the electron storage chamber 23 for generating free electrons 24 inside the electron storage chamber 23 .

The laser heating system includes a nanosecond laser 7, a second reflector 6 and a second focus mirror 11; the laser beam emitted by the nanosecond laser 7 is reflected by the second reflector 6 and then focused by the second focus mirror 11 On the surface of the workpiece 20 to be processed, it is used to make the charged black paint particles 17 form a black paint deposition layer 19 on the surface of the workpiece 20 to be processed; The focus position makes the laser beam focus on the black paint particle 17 adsorption layer on the black paint deposition layer 19 upper surface all the time; the laser shot peening strengthening system includes a femtosecond laser 4, the first reflecting mirror 5 and the first focusing mirror 10; The laser beam emitted by the femtosecond laser 4 is reflected by the first reflecting mirror 5 and then focused to the upper surface of the black paint deposition layer 19 by the first focusing mirror 10 .

The motion system comprises a first slide rail 1, a first slide block 2, a second slide block 3, a second slide rail 12, a third slide block 13 and a mobile platform 21, and the first slide block 2, the second slide block The blocks 3 are installed on the first slide rail 1 respectively; the first slide block 2 is connected with the first reflector 5, and the second slide block 3 is connected with the second reflector 6; the third slide block 13 is installed On the second slide rail 12; the third slide block 13 is connected with the second focusing mirror 11, and by driving the second focusing mirror 11 to move up and down so as to change the relative position of the focus relative to the black paint deposition layer 19 and the optical glass 14 in real time, use The focus position of the second focusing mirror 11 is changed; the workpiece 20 to be processed is placed on the mobile platform 21, and the mobile platform 21 is connected to the motion controller 18, and the maximum distance between the optical glass 14 and the mobile platform 21 can reach 10 mm.

The device of the present invention that can realize multiple laser shot peening under the rigid constrained layer also includes a three-dimensional information collector 9, a pressure sensor 31 and a displacement sensor 15, the three-dimensional information collector 9 is aligned with the lower surface of the optical glass, and Whether there is black paint vaporization attached to the lower surface of catching optical glass 14; Described displacement sensor 15 is used for detecting the distance between the thickness of black paint deposition layer 19 and black paint deposition layer 19 and optical glass 14; Described pressure sensor 31 Used to detect the pressure in a closed flow channel.

The computer 8 controls the first slider 2, the second slider 3, the femtosecond laser 4, the nanosecond laser 7, the three-dimensional information collector 9, the third slider 13, the displacement sensor 15, the motion controller 18, and the electronic injector 22 , wind speed controller 29, pressure sensor 30, baffle controller 32, air pressure pump 33. The wind speed controller 29 is used to control the wind speed of the high-speed fan 25 . The baffle controller 32 is used to control the movable closure baffle on the pellet storage bin 28 . The motion controller 18 is used to control the movement of the mobile platform 21 .

As shown in Figure 2, the processing method of the device described in the present invention that can realize multiple laser shot peening under the rigid constrained layer includes the following steps:

The air pump 33 is used to fill the closed channel with high-pressure gas, and when the pressure sensor 31 reaches the first set value, the air pump 33 is closed;

By controlling the high-speed fan 25 to start, the black paint particles 17 in the particle storage box 28 are circulated in the closed flow channel; after the black paint particles 17 pass through the electronic storage chamber 23, the black paint particles 17 are charged by the electronic injector 22 ; Charged black paint particles 17 are adsorbed on the surface of workpiece 20 to be processed;

Control the movement of the second slider 3 so that the light of the nanosecond laser 7 is reflected by the second reflector 6 and reaches the surface of the workpiece 20 to be processed; the laser focus is used to align the black paint particle layer adsorbed on the surface of the workpiece 20 to be processed to form a black Paint deposition layer 19; When the thickness of black paint deposition layer 19 is determined to reach the design value by displacement sensor 15, close nanosecond laser 7;

Control the movement of the first slider 2, so that the light of the femtosecond laser 4 is reflected by the first reflector 5 and reaches the surface of the black paint deposition layer 19; the particle storage box 28 is divided into a circulation area and a black paint particle area by moving the platen mechanism 30; Control the movable closed baffle to make the flow area communicate with the closed flow channel; the black paint deposition layer 19 is laser peened by the laser generated by the femtosecond laser 4;

Use the three-dimensional information collector 9 to capture whether there is black paint vapor attached to the lower surface of the optical glass 14. When there is black paint vapor, the laser generated by the nanosecond laser 7 is focused on the lower surface of the optical glass 14 for laser cleaning; control the high-speed fan 25 wind speed, use the air flow in the closed flow channel to blow away the melted or vaporized black paint attachments.

During the laser peening process, the displacement sensor 15 monitors the thickness of the black paint deposition layer 19 in real time, and when the thickness of the black paint deposition layer 19 is less than the second set value, the laser peening process is stopped and the movable closed baffle is controlled. Make the black paint particle area communicate with the closed flow channel, start by controlling the high-speed fan 25, make the charged black paint particles 17 adsorb on the surface of the black paint deposition layer 19 to be deposited; control the light of the nanosecond laser 7 to be reflected by the second reflector 6 Arrive at the surface of the black paint deposition layer 19 ; the black paint particle layer adsorbed on the surface of the black paint deposition layer 19 is aimed at the laser focus to supplement the black paint deposition layer 19 .

According to the monitoring value of the displacement sensor 15, the focus position of the nanosecond laser 7 is controlled, so that the thickness of the black paint deposition layer 19 is 1-100 μm; by controlling the mobile platform 21, the distance between the black paint deposition layer 19 and the optical glass 14 is 5-20 μm, which ensures that the optical glass 14 has a restraining effect on the laser shot peening, and is not easy to break the optical glass; the maximum distance between the mobile platform 21 and the optical glass 14 is 10mm, which is convenient for the flow of black paint particles 17 and black paint deposition 19 depositions. The diameter of the particles in the particle storage tank 28 is within 1 μm; the black paint grinder 27 crushes the cooled block black paint into particles with a diameter less than 1 μm.

When the nanosecond laser 7 heated the black paint particles 17 to form the black paint deposition layer 19, the flow velocity of the high-speed fan 25 was 1 to 10mm/s, and the movable closed baffle plate was controlled to move down to increase the flow section; When the second laser 4 is laser peening the black paint deposition layer 19, the flow velocity of the high-speed fan 25 is 10 to 100mm/s, and the movable closed baffle is controlled to move up to reduce the flow section; when the nanosecond laser 7. When the laser generated by 7 cleans the lower surface of the optical glass 14, the flow rate of the high-speed fan 25 is 100-1000mm/s, and the movable closed baffle is controlled to move up to reduce the flow section.

The nanosecond laser 7 adopts a square spot with a side length of 0.1-1mm, the laser energy is 0.03-5mJ, and the laser pulse width is 5-10ns; the femtosecond laser 4 adopts a circular spot with a spot diameter of 3-5mm. The laser energy is 3-15mJ, and the laser pulse width is 300-500fs.

The flow rate of electrons ejected by the electron injector 22 is much greater than the instantaneous flow rate of the particles in the closed flow channel passing through the high-speed fan 25, ensuring that more than 95% of the black paint particles 17 are negatively charged and can be adsorbed on the surface of the metal workpiece to form a short-term 1-3s. A thin layer of black paint particle layer, this is because of homosexual repulsion when the particles are charged; when the particle electrons are plundered by the metal workpiece and become uncharged, the non-adsorption effect will cause the black paint particles 17 to be blown away by the high-speed and high-pressure fluid , which not only prevents the black paint particles 17 from adhering to each other, but also facilitates the black paint deposition layer 19 to be repaired point by point with high precision and rapidly deposited layer by layer. When the black paint particles 17 are heated and melted to form the black paint deposition layer 19, the contact between the black paint deposition layer 19 and the metal workpiece for more than 3 seconds will become electrically neutral, and the black paint deposition layer 19 can absorb black paint for a short period of 1 to 3 seconds. particles17.

The method that can realize multiple laser shot peening under the rigid constrained layer in embodiment 1 comprises the following steps:

S1: The workpiece 20 to be processed is installed in the working tank, and the workpiece 20 to be processed is a metal workpiece. Generally micro/nano mechanical electronics and MEMS products. Open the air pump 33 to fill the closed channel with high-pressure gas, and close the air pump 33 when the pressure sensor 30 reaches 2-5atm;

S2: The computer 8 controls the electronic injector 22, the wind speed controller 29, the cooling rod 26, and the particle pulverizer 27 to turn on, so that the black paint particles 17 in the particle storage box 28 circulate in the closed flow channel, and the black paint particles 17 are electronically stored. The cavity 23 is negatively charged, and the charged black paint particles 17 have a short-term adsorption effect when passing through the surface of the metal workpiece;

S3: The computer 8 controls the movement of the second slider 3, so that the light of the nanosecond laser 7 is reflected by the second mirror 6 and arrives at the coordinate origin of the processing area. At this time, start the nanosecond laser 7, the motion controller 18, and the third slider. The block 13 and the non-contact infrared rangefinder, the motion controller 18 controls the three-dimensional movement of the mobile platform 21, and the laser focus is aimed at the black paint particle layer temporarily adsorbed on the surface of the metal workpiece 20, so that it melts and accumulates gradually to form a black paint deposition layer 19, observe the thickness of the black paint deposition layer 19 with a non-contact infrared rangefinder, close the nanosecond laser 7, the third slide block 13, the wind speed controller 29 after reaching a suitable thickness, and start the second slide block 3 to control the second The reflector 6 is far away from the top of the workbench, and the motion controller 18 controls the mobile platform 21 to return to its original position and rise a certain distance, so that the distance between the black paint deposition layer and the optical glass 14 is suitable;

S4: The computer 8 controls the movement of the first slider 2, so that the light of the femtosecond laser 4 is reflected by the first reflector 5 and arrives at the coordinate origin of the processing area, and the moving platen mechanism 30 is started to divide the particle storage box 28 into a circulation area and a black paint In the particle area, control the movable closed baffle to connect the flow area with the closed flow channel; and control the wind speed controller 29 to make the gas reach an appropriate flow rate. At this time, start the femtosecond laser 4, the motion controller 18, and the three-dimensional information collection Device 9, realizes multiple times of laser shot peening to black paint deposition layer 19;

S5: The non-contact infrared range finder monitors the thickness of different sections on the entire plane of the black paint deposition layer 19 at any time, and when the thickness of a certain section is lower than a certain range, repeat the operation of S3 to supplement the black paint deposition layer 19 in a directional manner;

S6: The three-dimensional information collector 9 captures at any time whether there is black paint vapor attached to the lower surface of the optical glass 14, and if so, starts the second slider 3, the nanosecond laser 7, the motion controller 18, the third slider 13, and the wind speed control Device 29, baffle controller 32, select appropriate laser parameters to focus the laser focus on the black area to melt or vaporize the black paint attachment, the baffle controller 32 controls the baffle to be higher than the particle storage height in the particle storage box 28, The wind speed controller 29 controls the wind speed of the high-speed fan 25, so that the pure high-pressure airflow in the pipeline flows at a high speed and blows away the melted or gasified black paint attachments;

S7: cycle S4-S6, complete the laser shot peening of the workpiece, and close all equipment.

It should be understood that although this description is described according to various embodiments, not each embodiment only includes an independent technical solution, and this description of the description is only for clarity, and those skilled in the art should take the description as a whole , the technical solutions in the various embodiments can also be properly combined to form other implementations that can be understood by those skilled in the art.

The series of detailed descriptions listed above are only specific descriptions for feasible embodiments of the present invention, and they are not intended to limit the protection scope of the present invention. Any equivalent embodiment or All changes should be included within the protection scope of the present invention.

Claims (10)

1. A device capable of realizing multiple times of laser shot peening forming under a rigid constraint layer is characterized by comprising a motion system, a laser shot peening strengthening system, a laser heating system, a particle flowing system and a working tank,

a workpiece (20) to be processed is arranged in the working groove, the working groove is communicated with the particle flow system to form a closed loop, and charged black paint particles (17) are adsorbed on the surface of the workpiece (20) to be processed through the particle flow system; the laser heating temperature rising system is used for enabling charged black paint particles (17) to form a black paint deposition layer (19) on the surface of a workpiece (20) to be processed; the laser shot blasting strengthening system is used for carrying out laser shot blasting on the surface of a workpiece (20) to be processed; the motion system is used for enabling the laser shot peening system, the laser heating temperature rising system and the workpiece (20) to be processed to move.

2. Device capable of achieving multiple laser shot peening formations under rigid constraining layers according to claim 1, characterized in that the particle flow system comprises a housing (16), an electronic ejector (22), an electronic storage chamber (23), a high speed fan (25), a refrigeration rod (26), a particle crusher (27), a particle storage tank (28), a pressure sensor probe (31) and a pneumatic pump (33);

a working groove is arranged in a closed flow channel of the shell (16), optical glass (14) is arranged on the shell above the working groove, and a particle crusher (27), a particle storage box (28), a high-speed fan (25), an electronic storage cavity (23) and a workpiece (20) to be processed are sequentially arranged in the closed flow channel according to the flow direction; the particle storage box (28) is internally provided with black paint particles, and the refrigeration stick (26) is used for cooling the recycled vaporized black paint; the particle crusher (27) is used for crushing the cooled black paint into black paint particles; the outlet of the particle crusher (27) is provided with a pneumatic pump (33) for keeping the pressure in the closed flow channel; the upper half part of one side wall surface of the particle storage box (28) is of a mesh structure, and the lower half part of one side wall surface of the particle storage box (28) is a closed boundary; the other side wall surface of the particle storage box (28) is a double-layer baffle, one layer of baffle is a mesh baffle, and the other layer of baffle is a movable closed baffle; the particle storage tank (28) is provided with a movable platen mechanism (30) which is used for dividing the particle storage tank (28) into a circulation area and a black paint particle area; the upper side and the lower side of the electronic storage cavity (23) are of a net structure, and an electronic ejector (22) is mounted on the electronic storage cavity (23) and used for generating free electrons (24) in the electronic storage cavity (23).

3. Device capable of achieving multiple laser shot peening under a rigid constraining layer according to claim 1, characterized in that the laser heating temperature raising system comprises a nanosecond laser (7), a second mirror (6) and a second focusing mirror (11); the laser beam emitted by the nanosecond laser (7) is reflected by the second reflecting mirror (6) and then focused on the surface of the workpiece (20) to be processed through the second focusing mirror (11) to form a black paint deposition layer (19) on the surface of the workpiece (20) to be processed by the black paint particles (17) with charges; when the height of the black paint deposition layer (19) is increased, the laser beam is focused on the black paint particle (17) adsorption layer on the upper surface of the black paint deposition layer (19) by changing the focal position of the second focusing lens (11); the laser shot peening system comprises a femtosecond laser (4), a first reflecting mirror (5) and a first focusing mirror (10); and laser beams emitted by the femtosecond laser (4) are reflected by the first reflector (5) and then focused to the upper surface of the black paint deposition layer (19) through the first focusing mirror (10).

4. The device capable of achieving multiple times of laser shot peening forming under the rigid constraint layer is characterized in that the motion system comprises a first slide rail (1), a first slide block (2), a second slide block (3), a second slide rail (12), a third slide block (13) and a moving platform (21), wherein the first slide block (2) and the second slide block (3) are respectively installed on the first slide rail (1); the first sliding block (2) is connected with the first reflector (5), and the second sliding block (3) is connected with the second reflector (6); the third sliding block (13) is arranged on the second sliding rail (12); the third sliding block (13) is connected with the second focusing mirror (11) and is used for changing the focus position of the second focusing mirror (11); and a workpiece (20) to be processed is placed on the moving platform (21).

5. The device capable of realizing multiple times of laser shot peening forming under the rigid constraint layer is characterized by further comprising a three-dimensional information collector (9), a pressure sensor (31) and a displacement sensor (15), wherein the three-dimensional information collector (9) is aligned to the lower surface of the optical glass and is used for capturing whether black paint vapor is attached to the lower surface of the optical glass (14); the displacement sensor (15) is used for detecting the thickness of the black paint deposition layer (19) and the distance between the black paint deposition layer (19) and the optical glass (14); the pressure sensor (31) is used for detecting the pressure in the closed flow channel.

6. A method for processing an apparatus capable of achieving multiple times of laser peening forming under a rigid constraint layer according to any one of claims 1 to 5, comprising the steps of:

the closed flow channel is filled with high-pressure gas through a pneumatic pump (33), and the pneumatic pump (33) is closed when the pressure sensor (31) reaches a first set value;

the black paint particles (17) in the particle storage box (28) circularly flow in the closed flow passage by controlling the high-speed fan (25) to be started; the black paint particles (17) pass through the electronic storage cavity (23) and then are charged through the electronic ejector (22); the charged black paint particles (17) are adsorbed on the surface of a workpiece (20) to be processed;

controlling the second sliding block (3) to move, so that the light of the nanosecond laser (7) is reflected by the second reflecting mirror (6) to reach the surface of the workpiece (20) to be processed; aiming at the black paint particle layer absorbed on the surface of the workpiece (20) to be processed through the laser focus to form a black paint deposition layer (19); when the thickness of the black paint deposition layer (19) is determined to reach a design value through the displacement sensor (15), the nanosecond laser (7) is turned off;

controlling the first sliding block (2) to move, so that the light of the femtosecond laser (4) is reflected by the first reflecting mirror (5) to reach the surface of the black paint deposition layer (19); dividing a particle storage tank (28) into a circulation area and a black paint particle area by moving a platen mechanism (30); controlling the movable sealing baffle plate to enable the circulation area to be communicated with the sealing flow channel; performing laser shot blasting on the black paint deposition layer (19) by laser generated by a femtosecond laser (4);

whether black paint vapor attached to the lower surface of the optical glass (14) exists or not is captured through the three-dimensional information collector (9), and when the black paint vapor exists, laser generated by the nanosecond laser (7) is focused on the lower surface of the optical glass (14) for laser cleaning; the air speed of the high-speed fan (25) is controlled, and melted or gasified black paint attachments are blown away by the flowing of air flow in the closed flow channel.

7. The method for processing an apparatus capable of performing multiple laser peening forming under a rigid constraint layer according to claim 6, further comprising the steps of:

in the laser shot blasting process, the displacement sensor (15) monitors the thickness of the black paint deposition layer (19) in real time, when the thickness of the black paint deposition layer (19) is smaller than a second set value, laser shot blasting processing is stopped, the movable sealing baffle is controlled to enable the black paint particle area to be communicated with the sealing flow channel, and the high-speed fan (25) is controlled to start, so that the black paint particles (17) with charges are adsorbed on the surface of the black paint deposition layer (19); controlling the light of the nanosecond laser (7) to be reflected by the second reflector (6) to reach the surface of the black paint deposition layer (19); the black paint particle layer adsorbed on the surface of the black paint deposition layer (19) is focused by laser to supplement the black paint deposition layer (19).

8. The processing method of the device capable of realizing multiple times of laser shot peening forming under the rigid constraint layer is characterized in that the position of a focus point of a nanosecond laser (7) is controlled according to a monitoring value of a displacement sensor (15), so that the thickness of the black paint deposition layer (19) is 1-100 μm; controlling a moving platform (21) to enable the distance between the black paint deposition layer (19) and the optical glass (14) to be 5-20 mu m; the particle diameter in the particle storage tank (28) is within 1 mu m; and the black paint crusher (27) crushes the blocky black paint after temperature reduction into particles with the diameter less than 1 mu m.

9. The machining method of the device capable of realizing multiple times of laser shot peening under the rigid constraint layer is characterized in that the electron jet (22) jets the electron flow rate which is far larger than the instantaneous flow rate of particles in the closed flow channel through the high-speed fan (25); when the nanosecond laser (7) heats the black paint particles (17) to form a black paint deposition layer (19), the flow rate of the high-speed fan (25) is 1-10 mm/s, and the movable sealing baffle is controlled to move downwards to increase the flow cross section; when the femtosecond laser (4) carries out laser shot blasting on the black paint deposition layer (19), the flow rate of the high-speed fan (25) is 10-100 mm/s, and the movable sealing baffle is controlled to move upwards to reduce the flow cross section; when the laser generated by the nanosecond laser (7) cleans the lower surface of the optical glass (14), the flow rate of the high-speed fan (25) is 100-1000 mm/s, and the movable sealing baffle is controlled to move upwards to reduce the flow cross section.

10. The processing method of the device capable of realizing the multiple laser shot peening forming under the rigid constraint layer according to claim 6, wherein the nanosecond laser (7) adopts a square light spot, the side length of the light spot is 0.1-1mm, the laser energy is 0.03-5 mJ, and the pulse width of the laser is 5-10ns; the femtosecond laser (4) adopts a circular light spot, the diameter of the light spot is 3-5mm, the laser energy is 3-15 mJ, and the laser pulse width is 300-500fs.

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