CN112775546A

CN112775546A - Method and device for realizing connection of two heterogeneous materials by using laser

Info

Publication number: CN112775546A
Application number: CN202011580067.9A
Authority: CN
Inventors: 马修泉; 张琳; 吴寒; 闻锦程; 邢胜博
Original assignee: Huazhong University of Science and Technology
Current assignee: Huazhong University of Science and Technology
Priority date: 2020-12-28
Filing date: 2020-12-28
Publication date: 2021-05-11

Abstract

The invention belongs to the technical field related to laser material processing, and discloses a method and a device for realizing connection of two heterogeneous materials by using laser, wherein the method comprises the following steps: the two heterogeneous materials are vertically stacked and fixed, and are irradiated from the upper part by laser, so that the heterogeneous material on the upper layer is penetrated and ablated to form a pore, the heterogeneous material on the lower layer is melted and then diffused to the pore, and the two heterogeneous materials are stably connected after being condensed. This application makes a material appear the hole by the sintering through laser beam, and another kind of material is melted the back and flows and get into this hole in the condensation, realizes two heterogeneous material's connection, easy operation, pollution-free, with low costs, the industrialization of being convenient for is used.

Description

Method and device for realizing connection of two heterogeneous materials by using laser

Technical Field

The invention belongs to the technical field related to laser material processing, and particularly relates to a method and a device for realizing connection of two heterogeneous materials by using laser.

Background

In recent years, heterogeneous material connectors are widely applied to products in multiple fields, including certain high-precision measuring instruments, solar cells, digital electronic products, machine touch panels, automobile processing and manufacturing safety switches, aerospace glass-metal alloy connectors, laser front-section protective caps in the laser manufacturing field and the like. The common connection techniques at present mainly include anode connection, semi-solid connection, active metal welding, soldering, mechanical connection, adhesive bonding, matching connection and the like. The anode connection has very high requirement on the air tightness of materials, and simultaneously requires the coating of a metal surface, the air tightness of the materials can be influenced by the imperfect coating, and the process is complex and is not beneficial to large-scale processing and manufacturing; semisolid connection can only process specific materials with specific sizes, and meanwhile, a high-temperature environment is needed in the processing process, so that adverse effects can be caused on some materials which cannot resist high temperature, and the process is complicated; the main problems of the glue joint are that the connecting material is not resistant to high temperature and illumination, the connecting strength and the air tightness are affected at extremely high temperature, and the connecting material is a pollutant for the connecting piece; the mating connection is cooled after heating in the furnace, resulting in long production cycles; other modes mainly have the defects that the connection strength is generally not high and cannot meet the requirement of industrial application. Therefore, it is desirable to design a method and apparatus for connecting two heterogeneous materials by using laser.

Disclosure of Invention

Aiming at the defects or the improvement requirements of the prior art, the invention provides a method and a device for realizing the connection of two heterogeneous materials by using laser.

To achieve the above object, according to one aspect of the present invention, there is provided a method for connecting two heterogeneous materials using a laser, the method comprising: the two heterogeneous materials are vertically stacked and fixed, and are irradiated from the upper part by laser, so that the heterogeneous material on the upper layer is penetrated and ablated to form a pore, the heterogeneous material on the lower layer is melted and then diffused to the pore, and the two heterogeneous materials are stably connected after being condensed.

Preferably, the upper layer material of the heterogeneous material is a material completely ablated by the laser, and the lower layer material of the heterogeneous material is a material melted and flowed by the laser.

Preferably, the upper layer material is glass, and the lower layer material is metal.

Preferably, the structure of the upper layer material is a flat plate with a non-through surface, the structure of the lower layer material is a plane with a through surface through a hole, and the vertically stacking and fixing of the two heterogeneous materials specifically comprises:

and (3) vertically stacking the two heterogeneous materials above a vacuum environment, and pressing and fixing the two heterogeneous materials by forming pressure difference on two sides of the materials through atmospheric pressure and the vacuum environment.

Preferably, the method further comprises focusing the laser so that the focused laser point is located in the range of 0.05 mm-0.3 mm on the contact surface of the two heterogeneous materials.

According to another aspect of the present invention, there is provided an apparatus for implementing the method for connecting two heterogeneous materials by using laser, the apparatus comprising: the clamping structure comprises a vacuum pump clamp, a vacuum pump and a silicone tube, the vacuum pump clamp is connected with the vacuum pump through the silicone tube, the vacuum pump clamp comprises a first hole which is partially communicated from the upper end face downwards and a second hole which is completely communicated with the first hole from the side face, the silicone tube is connected with the second hole, the vacuum pump clamp further comprises a groove which is downward from the upper end face, and the groove is used for containing the lower-layer material; the laser is arranged above the vacuum pump clamp and used for transmitting pulse signals to the two superposed heterogeneous materials; and the moving device is arranged below the vacuum pump clamp and is used for adjusting the position of the vacuum pump clamp.

Preferably, the mobile device include with vacuum pump anchor clamps sub-unit connection's electric rotary table, support, electric rotary table is used for driving vacuum pump anchor clamps rotate, be equipped with on the support along vertical z axle direction slide rail, electric rotary table follows the slide rail rises or descends, the mobile device still includes along the crossbeam of x direction and along the crossbeam of y direction, the crossbeam of x direction and the crossbeam surface of y direction all are equipped with the slide rail, the support is in slide in the slide rail on the crossbeam of x direction, the crossbeam of x direction is in slide in the slide rail of the crossbeam of y direction.

Preferably, the moving device further comprises a controller, and the controller is connected with the electric rotating table, the bracket, the beam in the x direction and the beam in the y direction in a communication manner.

Preferably, the depth of the recess is less than the thickness of the underlying material.

Preferably, the laser comprises a laser beam, a laser shutter arranged on a laser beam optical path, and a focusing lens arranged below the laser shutter.

Generally, compared with the prior art, the method and the device for realizing the connection of two heterogeneous materials by using laser provided by the invention have the following beneficial effects:

1. one material is sintered to form a pore through a laser beam, the other material flows into the pore after being melted and is condensed, the connection of the two heterogeneous materials is realized, the operation is simple, no pollution is caused, and the industrial application is facilitated;

2. the method is particularly suitable for connection of glass and metal, laser irradiates on the glass, electrons in the glass absorb pulse energy through multiphoton absorption and a tunnel effect, the electrons are subjected to impact ionization and avalanche ionization to generate a large amount of free electrons, then the energy of the free electrons is transferred to crystal lattices, the crystal lattices generate phase explosion and plasma eruption, so that the glass is punched, meanwhile, the rest energy is deposited on the surface of the metal, the surface of the metal is heated and melted, substances are upwards diffused into holes of the glass, and then the metal is deposited in the holes through a condensation process, so that the firm connection of the glass and the metal is realized;

3. the metal and the glass are connected through the pressure difference, an external mechanical clamping structure is not needed, the metal or the glass cannot be scratched or crushed, and the precision is high;

4. the vacuum pump is adopted to fix the two heterogeneous materials, the lower layer material is arranged in the groove to realize the primary fixation of the lower layer material, and the upper layer material is hermetically covered on the lower layer material to form the internal and external pressure difference so as to realize the fixation of the two heterogeneous materials, so that the hard mechanical structure is not involved, the heterogeneous materials cannot be damaged, and the vacuum pump is very suitable for the connection of precision instruments;

5. the moving device adopts a shaft which can rotate and move in XYZ directions, the moving direction is flexible, and the requirement of punching in multiple directions can be met;

6. the focusing lens in the laser can focus the focus so as to realize energy concentration and reduce the strict requirement on the energy of the laser beam.

Drawings

Fig. 1A schematically shows a punching process of the upper layer material of the present embodiment;

FIG. 1B schematically shows the melting process of the underlying material of the present embodiment;

FIG. 1C schematically illustrates the diffusion process of the underlying material of this embodiment;

FIG. 1D schematically illustrates the solidification of the underlying material of this embodiment;

fig. 2 schematically shows an apparatus for implementing the method for connecting two heterogeneous materials by using laser according to the present embodiment;

fig. 3 schematically shows an oblique view of the vacuum pump jig of the present embodiment;

figure 4 schematically shows a cross-sectional view of an oblique view of the vacuum pump fixture of figure 3 of the present embodiment;

FIG. 5 is a schematic diagram showing the structure of a focused focal point of the present embodiment;

FIG. 6 is a schematic view showing the structure of laser-drilled fusing of the present embodiment;

FIG. 7 is a sectional view schematically showing the laser-drilled melted structure of FIG. 6 according to the present embodiment;

fig. 8 schematically shows a connection diagram of the upper layer material and the lower layer material under the electron microscope according to the embodiment.

The same reference numbers will be used throughout the drawings to refer to the same or like elements or structures, wherein:

100-clamping structure:

110-vacuum pump clamp; 120-a vacuum pump; 130-silicone tube; 111-a first hole; 112-a second aperture; 113-a groove;

200-laser:

210-a laser beam; 220-laser shutter; 230-a focusing lens;

300-mobile device:

310-electric rotating table; 320-a bracket; a beam in the 330-x direction; a beam in the 340-y direction; 350-a controller;

400-heterogeneous material.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention. In addition, the technical features involved in the embodiments of the present invention described below may be combined with each other as long as they do not conflict with each other.

The invention provides a method for realizing connection of two heterogeneous materials by using laser, which comprises the following steps: the two heterogeneous materials are vertically stacked and fixed, and are irradiated from the upper part by laser, so that the heterogeneous material on the upper layer is penetrated and ablated to form a pore, the heterogeneous material on the lower layer is melted and then diffused to the pore, and the two heterogeneous materials are stably connected after being condensed.

The upper layer material of the heterogeneous material is completely ablated by laser. The lower layer material of the heterogeneous material is a material which is melted and flows by laser, and the material can absorb the laser to form plasma and the like to present a eruption state, so that substances are upwards diffused into the holes and form stable and firm connection after condensation. In this embodiment, the upper layer is preferably made of glass, the lower layer is preferably made of metal, the upper layer is made of a glass plate with a non-through upper and lower surface, and the lower layer is made of an aluminum alloy ring. The basic principle is that ultrafast laser interacts with a transparent medium, and the glass absorbs pulse energy through nonlinearity, and the process is roughly divided into that electrons in the glass absorb the pulse energy through multiphoton absorption and a tunnel effect, and the electrons are subjected to impact ionization and avalanche ionization to generate a large amount of free electrons so as to form plasma. Then, the energy of free electrons is transferred to crystal lattices, phase explosion and plasma eruption are generated in the crystal lattices, so that glass is punched (as shown in fig. 1A), meanwhile, the rest energy is deposited on the surface of metal, so that the surface of the metal is heated and melted (as shown in fig. 1B), substances are upwards diffused into the holes of the glass (as shown in fig. 1C), and then, through a condensation process, the metal is deposited in the holes (as shown in fig. 1D), so that glass-metal connection is realized.

The pulse energy of the embodiment can just realize the perforation of the glass, and the other part of the pulse energy can melt the metal surface to enable the brief substances to be upwards diffused into the holes in the glass, and the stable connection is formed after the metal surface is condensed. When the laser diffusion hole is in work, the time of the laser acting on the glass and the metal is controlled, so that the pulse quantity and energy acting on the heterogeneous material are indirectly controlled, and the quality of the metal diffused into the hole is controlled.

The laser used in this example had a laser pulse with a time interval of 5Hz, a pulse width of 35fs, a pulse energy of 5mJ, and a wavelength of 800 nm. When the laser energy is insufficient, the laser can be focused, so that the focused laser point is positioned in the range of 0.05 mm-0.3 mm on the contact surface of the two heterogeneous materials.

In this embodiment, the glass is subjected to laser drilling, and the shape of the hole may be cylindrical, inverted conical, or the like, and may be determined according to the property of the sample to be connected, the position of the laser focus, or the like. The number and the position of the holes are determined according to the connection requirement, the embodiment realizes the connection of the glass and the aluminum alloy ring by punching one circle of the heterogeneous material, and the distance between the center of the hole and the center of the hole is 5 mm.

In another aspect, the present invention provides an apparatus for implementing the method for connecting two heterogeneous materials 400 by using laser, as shown in fig. 2, the apparatus includes a holding structure 100, a laser 200, and a moving device 300.

The clamping structure 100 includes a vacuum pump clamp 110, a vacuum pump 120, and a silicone tube 130, wherein the vacuum pump clamp 110 is connected to the vacuum pump 120 through the silicone tube 130. As shown in fig. 3 and 4, the vacuum pump jig 110 includes a first hole 111 penetrating from an upper end to a lower portion and a second hole 112 completely penetrating from a side surface to the first hole 111, the silicone tube 130 is connected to the second hole 112, and the vacuum pump jig 110 further includes a groove 113 facing downward from the upper end, the groove 113 being configured to receive the lower layer material. The depth of the recess 113 is less than the thickness of the underlying material. The shape of the groove can be cylindrical, polygonal, square, etc., and the embodiment is preferably cylindrical with a diameter of 25 mm.

As shown in fig. 6 and 7, in operation, a lower layer material such as an aluminum alloy ring is accommodated in the groove, an upper layer material such as a glass plate is covered on the aluminum alloy ring, the vacuum pump 120 is started to extract gas, so that an approximately vacuum environment is provided inside the vacuum pump clamp 110, a negative pressure is formed, and a pressure difference is formed between the vacuum environment and the external atmospheric pressure. In this embodiment, the vacuum pump 120 is always in a working state, the rated voltage is 220V, the negative pressure with the pressure difference of at most-85 KPa can be generated, theoretically, the maximum force of 26N can be generated at the interface between the aluminum alloy ring and the glass, and the output negative pressure can be controlled by adjusting the output power of the vacuum pump 120, so as to indirectly change the magnitude of the applied pressure between the glass and the aluminum alloy ring.

A laser 200 is disposed above the vacuum pump fixture 110, and the laser 200 is used for emitting a pulse signal to the two heterogeneous materials placed in a superimposed manner. The laser 200 includes a laser beam 210, a laser shutter 220 disposed on an optical path of the laser beam 210, and a focusing lens 230 disposed below the laser shutter 220. The laser shutter 220 is used for controlling the pulse number and time of the laser beam to realize the output and closing of the laser beam; the focusing lens 230 is used to focus the laser beam. In this embodiment, the focal length of the focusing lens 230 is 50mm, and the focused focal point is located in the range of 0.05mm to 0.3mm on the contact surface of the two heterogeneous materials 400, as shown in fig. 5, and is more preferably 0.1 mm.

The moving means 300 is disposed below the vacuum pump jig 110, and is used to adjust the position of the vacuum pump jig 110 to facilitate laser drilling by the laser beam.

The moving device 300 includes an electric rotating platform 310 and a support 320 connected to the lower portion of the vacuum pump fixture 110, the electric rotating platform 310 is used for driving the vacuum pump fixture 110 to rotate, a slide rail along the vertical z-axis direction is disposed on the support 320, and the electric rotating platform 310 ascends or descends along the slide rail.

The moving device 300 further includes a cross beam 330 along the x direction and a cross beam 340 along the y direction, both surfaces of the cross beam 330 along the x direction and the cross beam 340 along the y direction are provided with slide rails, the bracket 320 slides in the slide rails on the cross beam 330 along the x direction, and the cross beam 330 along the x direction slides in the slide rails of the cross beam 340 along the y direction.

The mobile device 300 further comprises a controller 350, wherein the controller 350 is communicatively connected to the electric rotating table 310, the support 320, the beam 330 in the x direction, and the beam 340 in the y direction.

The working process of the device is as follows: the method comprises the steps of firstly, arranging a lower layer of material in a groove, covering an upper layer of material on the groove, starting a power supply of a vacuum pump, enabling the inside and the outside of a vacuum pump clamp to form a pressure difference, clamping two heterogeneous materials at the moment, and controlling the rotation of an electric rotary table and the movement of a support, a cross beam and the like through a controller to enable the two heterogeneous materials to be located at proper positions of a laser focus point. The laser shutter is opened, laser beams pass through the laser shutter and are focused inside the two heterogeneous materials by the focusing lens, the surface of the glass is rapidly broken down to form holes due to high peak pulse energy of the laser, the pulse energy continues to act on the surface of the lower layer material, the melted substances on the surface of the lower layer material are upwards diffused, enter the upper layer material and are condensed, and then the upper layer material and the melted substances are well connected (as shown in figure 8). And repeating the steps to realize the connection of the next hole through the rotation of the electric rotating table.

To sum up, this application realizes the connection of two heterogeneous materials through the mode that laser beam drilling melts and solidifies, need not whole high temperature, need not the coating film, does not produce the pollutant, and easy operation environmental protection is suitable for mass production, is applicable to the requirement of industrialization production very much.

It will be understood by those skilled in the art that the foregoing is only a preferred embodiment of the present invention, and is not intended to limit the invention, and that any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the scope of the present invention.

Claims

1. A method for connecting two dissimilar materials by using a laser, the method comprising:

the two heterogeneous materials are vertically stacked and fixed, and are irradiated from the upper part by laser, so that the heterogeneous material on the upper layer is penetrated and ablated to form a pore, the heterogeneous material on the lower layer is melted and then diffused to the pore, and the two heterogeneous materials are stably connected after being condensed.

2. The method of claim 1, wherein the upper layer of heterogeneous material is a material that is completely ablated by the laser and the lower layer of heterogeneous material is a material that is melted and flowed by the laser.

3. The method of claim 2, wherein the upper layer material is glass and the lower layer material is metal.

4. The method according to claim 3, wherein the upper layer material is structured as a flat plate with a non-through surface, the lower layer material is structured as a flat plate with a through surface through holes, and the step of vertically stacking and fixing the two heterogeneous materials comprises the following specific steps:

and (3) vertically stacking the two heterogeneous materials above a vacuum environment, and compressing and fixing the two heterogeneous materials through the pressure difference between atmospheric pressure and the vacuum environment.

5. The method of claim 1, further comprising focusing the laser such that the focused laser spot is in the range of 0.05mm to 0.3mm on the interface of the two dissimilar materials.

6. An apparatus for implementing the method for connecting two heterogeneous materials by using laser according to any one of claims 1 to 5, wherein the apparatus comprises:

the clamping structure (100) comprises a vacuum pump clamp (110), a vacuum pump (120) and a silicone tube (130), wherein the vacuum pump clamp (110) is connected with the vacuum pump (120) through the silicone tube (130), the vacuum pump clamp (110) comprises a first hole (111) which penetrates from the upper end to the lower part and a second hole (112) which completely penetrates from the side surface to the first hole (111), the silicone tube (130) is connected with the second hole (112), the vacuum pump clamp (110) further comprises a groove (113) which penetrates from the upper end to the lower part, and the groove (113) is used for containing the lower-layer material;

the laser (200) is arranged above the vacuum pump clamp (110), and the laser (200) is used for emitting pulse signals to the two superposed heterogeneous materials;

and the moving device (300) is arranged below the vacuum pump clamp (110) and is used for adjusting the position of the vacuum pump clamp (110).

7. The device according to claim 6, wherein the moving device (300) comprises an electric rotating table (310) and a support (320) connected with the lower portion of the vacuum pump fixture (110), the electric rotating table (310) is used for driving the vacuum pump fixture (110) to rotate, a vertical z-axis direction sliding rail is arranged on the support (320), the electric rotating table (310) ascends or descends along the sliding rail, the moving device (300) further comprises a beam (330) along an x direction and a beam (340) along a y direction, sliding rails are arranged on the surfaces of the beam (330) along the x direction and the beam (340) along the y direction, the support (320) slides in the sliding rail on the beam (330) along the x direction, and the beam (330) along the x direction slides in the sliding rail of the beam (340) along the y direction.

8. The apparatus of claim 7, wherein the moving means (300) further comprises a controller (350), the controller (350) being communicatively connected to the motorized turntable (310), the support (320), the x-direction beam (330), and the y-direction beam (340).

9. The device according to claim 6, characterized in that the depth of the groove (113) is smaller than the thickness of the underlying material.

10. The apparatus of claim 6, wherein the laser (200) comprises a laser beam (210), a laser shutter (220) disposed in an optical path of the laser beam (210), and a focusing lens (230) disposed below the laser shutter (220).