CN116944675A

CN116944675A - Ultrafast laser welding method for transparent material and metal material

Info

Publication number: CN116944675A
Application number: CN202311093178.0A
Authority: CN
Inventors: 张伟; 蔡敏; 李梦阳; 张晓兵; 李元成; 焦佳能; 杨炳东
Original assignee: AVIC Beijing Aeronautical Manufacturing Technology Research Institute
Current assignee: AVIC Beijing Aeronautical Manufacturing Technology Research Institute
Priority date: 2023-08-28
Filing date: 2023-08-28
Publication date: 2023-10-27

Abstract

The invention provides an ultrafast laser welding method for transparent materials and metal materials, which comprises the following steps: stacking a transparent material above the metal material, enabling a first plane to be welded and a second plane to be welded to be opposite to each other, and clamping the transparent material and the metal material through a clamp; polishing and scanning a second plane to be welded through a transparent material by using first laser emitted by laser equipment, wherein the first laser enables the second plane to be welded to be melted, and the melted metal material flows under the pressure action of a clamp and fills up pits; regulating and controlling the focus of the laser equipment to be focused between a first plane to be welded and a second plane to be welded; and the second laser emitted by the laser equipment heats and melts the transparent materials and the metal materials on two sides of the joint surface along a preset welding path, and the welding seam is formed by cooling. The invention can not introduce other elements except welding materials into the welding seam, has no pollution in the whole process, is environment-friendly, and improves the problem of poor welding quality caused by uneven surface.

Description

Ultrafast laser welding method for transparent material and metal material

Technical Field

The invention relates to the technical field of laser welding processing, in particular to an ultrafast laser welding method for transparent materials and metal materials.

Background

With the development of the technology level, the modern industry has put requirements on engineering component performance at a higher level and with more functions. Besides ensuring mechanical properties, the material has the properties of good high temperature resistance, corrosion resistance, high strength and the like, and the multifunctional integrated and long service period becomes a hot spot for the current material processing research. The single metal material is difficult to meet the practical use requirements at the same time, and the dissimilar material connecting piece can utilize the respective advantages of the materials to the greatest extent, so that the material meets the requirements of different working environments and meanwhile the processing cost can be saved. At present, the connecting piece of transparent material and metal material has been widely used in the industries of aerospace, electronic information, automobile manufacturing and the like.

The main connection modes at present are as follows: anodic bonding, adhesive bonding, semi-solid bonding, and the like. However, each method has its own limitations, such as: anodic bonding uses specific equipment; the bonding has the problems of poor air tightness, poor heat conductivity and the like; the semi-solid connection needs to be subjected to heat pretreatment, and damage can be caused to temperature sensitive components; the requirement of the welding quality of the transparent material and the metal material is difficult to meet by adopting a traditional welding mode. The ultra-fast laser welding has the advantages of high processing precision, small heat affected zone, difficult fracture, high connection strength, no need of an intermediate layer or an adhesive in the whole welding process, no influence of high temperature or chemical substances on sensitive or organic elements, and application in micro-device welding in the fields of automobiles, electronics, medicine and the like. The surface state of the welding material, such as roughness and flatness, is strictly required by adopting ultra-fast laser welding. In the prior art, in order to realize high-strength welding of the transparent material and the metal material, methods such as manual polishing, mechanical polishing, electrochemical polishing and the like are generally adopted to reduce the roughness of the surface of the metal material so as to achieve the surface attaching state. Although the method can improve the roughness of the surface of the material, the polishing effect is highly dependent on the operation level of technicians, and the welding quality and the processing efficiency are difficult to ensure.

Disclosure of Invention

First, the technical problem to be solved

The invention aims to solve the technical problem of realizing high-quality welding connection of a transparent material and a metal material.

(II) technical scheme

In order to achieve the above purpose, the invention adopts the following technical scheme:

the invention provides an ultrafast laser welding method of a transparent material and a metal material, which is used for welding and connecting a first plane to be welded of the transparent material with a second plane to be welded of the metal material, wherein the surface of the second plane to be welded is provided with a plurality of pits, and the ultrafast laser welding method comprises the following steps:

step one, ultrasonically cleaning the transparent material and the metal material, stacking the transparent material above the metal material after cleaning, enabling the first plane to be welded and the second plane to be welded to be opposite, and clamping the transparent material and the metal material through a clamp;

step two, a laser device emits first laser, the first laser polishes and scans the second plane to be welded through the transparent material, the first laser enables the second plane to be welded to be melted, and the melted metal material flows under the pressure action of the clamp and fills the pits;

regulating and controlling a focus of laser equipment to enable the focus to be focused between the first plane to be welded and the second plane to be welded;

and fourthly, the laser equipment emits second laser, the second laser heats and melts transparent materials and metal materials on two sides of the joint surface along a preset welding path, and the welding seam is formed by cooling and molding, so that the welding connection between the first plane to be welded and the second plane to be welded is realized.

Preferably, the transparent material is sapphire glass, or quartz glass, or soda lime glass, or borosilicate glass.

Preferably, the metal material is aluminum, or a copper alloy, or stainless steel, or a titanium alloy.

Preferably, the line spacing of the first laser for polishing scanning is 0.01-0.1mm.

Preferably, the preset welding path is in a Z shape, a return shape, a bow shape or a straight shape.

Preferably, the laser device includes a polishing laser for emitting the first laser light and an ultrafast laser for emitting the second laser light.

Preferably, the ultrafast laser is a picosecond laser or a femtosecond laser.

Preferably, the polishing laser is a nanosecond laser or a continuous laser.

Preferably, the pulse repetition frequency of the polishing laser is 20-50kHz, the output power is 50-500W, and the wavelength of the first laser is 1064nm.

Preferably, the output wavelength of the ultrafast laser is 355-1064nm, the pulse width is 50 fs-10 ps, the pulse repetition frequency is 1 kHz-100 MHz, and the output power is 1-200W.

(III) beneficial effects

The technical scheme of the invention has at least the following advantages: according to the invention, the surface of the metal material is polished and scanned through the transparent material by the first laser, the metal material at the second plane to be welded is melted by the laser energy of the first laser, and the melted metal material flows and fills up the pits under the action of the clamping force provided by the clamp, so that the first plane to be welded and the second plane to be welded are tightly attached; and then the second laser is focused on the joint surface of the first plane to be welded and the second plane to be welded, the transparent material and the metal material on two sides of the joint surface are heated and melted, and the welding of the transparent material and the metal material is realized under the action of the clamping force provided by the clamp. The invention can not introduce other elements except welding materials into the welding seam, and can finish the laser welding of the high-quality transparent material and the metal material without adding additional materials, the whole welding process is pollution-free and environment-friendly, and the problem of non-ideal welding quality caused by uneven surface is solved.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings that are needed in the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.

Fig. 1 is a schematic flow chart of an ultrafast laser welding method for transparent materials and metal materials according to an embodiment of the present invention.

Fig. 2 is a schematic surface state diagram of a second plane to be welded according to an embodiment of the present invention.

Fig. 3 is a schematic view showing a surface state of a second plane to be welded after the first laser polishing scanning is completed according to an embodiment of the present invention.

Fig. 4 is a schematic diagram of a welding process of the second laser according to the embodiment of the present invention.

The reference numerals in the drawings are as follows:

1. a first laser; 2. a transparent material; 3. a metal material; 4. a second laser; 21. a first plane to be welded; 31. the second plane to be welded; 311. and (5) pit.

Detailed Description

In order to make the technical problems, technical schemes and beneficial effects to be solved more clear, the invention is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are for purposes of illustration only and are not intended to limit the scope of the invention.

It will be understood that when an element is referred to as being "mounted" or "disposed" on another element, it can be directly on the other element or be indirectly on the other element. When an element is referred to as being "connected" to another element, it can be directly connected or indirectly connected to the other element.

It is to be understood that the terms "length," "width," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," and the like are merely for convenience in describing the invention based on the orientation or positional relationship shown in the drawings, and are not to be construed as limiting the invention, as the indicating device or element must have a particular orientation, be constructed and operated in a particular orientation.

Furthermore, the terms "first," "second," and the like, are used for descriptive purposes only and are not to be construed as indicating relative importance or indicating the number of technical features. In the description of the present invention, the meaning of "a plurality" is two or more, unless explicitly defined otherwise. The following describes in more detail the specific implementation of the present invention in connection with specific embodiments:

as shown in fig. 1, 2, 3 and 4, an embodiment of the present invention provides an ultrafast laser welding method for welding a first plane to be welded 21 of a transparent material 2 with a second plane to be welded 31 of a metal material 3, wherein the surface of the second plane to be welded 31 has a plurality of pits 311, and the method includes the following steps:

step one, ultrasonically cleaning a transparent material 2 and a metal material 3, stacking the transparent material 2 above the metal material 3 after cleaning is finished, enabling a first plane to be welded 21 and a second plane to be welded 31 to be arranged oppositely, and clamping the transparent material 2 and the metal material 3 through a clamp; the purpose of the ultrasonic cleaning is to remove impurities or particulate matter adhering to the transparent material 2 and the metal material 3. Specifically, ultrasonic cleaning is performed by placing the transparent material 2 and the metal material 3 in alcohol. The transparent material 2 and the metal material 3 are placed on the machine tool, the transparent material 2 and the metal material 3 are fastened on the machine tool through the clamp arranged on the machine tool, the clamp is clamped on the upper surface of the transparent material 2, and downward pressure is applied to the transparent material 2 and the metal material 3 by the clamp, so that the first plane 21 to be welded of the transparent material 2 is tightly attached to the second plane 31 to be welded of the metal material 3.

Step two, the laser equipment emits first laser 1, the first laser 1 polishes and scans the second plane 31 to be welded through the transparent material 2, the first laser 1 enables the second plane 31 to be welded to be melted, and the melted metal material 3 flows under the pressure action of the clamp and fills the pit 311; by setting reasonable processing parameters of the first laser 1 and a movement mode and a path of a machine tool, the energy of the first laser 1 is transmitted to the second plane 31 to be welded in a heat conduction mode, so that the metal material positioned on the second plane 31 to be welded is melted, the melted metal material 3 flows under the action of clamping force and fills the pit 311, the welding interface is tightly attached, and the welding quality and efficiency are improved; the melted metal material 3 has a certain amount of heat, and the transparent material 2 and the metal material 3 on both sides thereof can be preheated, so that the possibility of cracking of the metal material 3 is reduced in the welding process of the second laser 4.

Step three, regulating and controlling the focus of the laser device to focus the focus between the first plane to be welded 21 and the second plane to be welded 31;

and step four, the laser equipment emits second laser 4, the second laser 4 heats and melts the transparent material 2 and the metal material 3 at two sides of the joint surface along a preset welding path, and the welding seam is formed by cooling and molding, so that the welding connection between the first plane 21 to be welded and the second plane 31 to be welded is realized. By setting reasonable processing parameters of the second laser 4 and a machine tool moving path, the second laser 4 is focused to a to-be-welded interface between the first to-be-welded plane 21 and the second to-be-welded plane 31 after a series of processes of energy absorption, beam diffraction and refraction occur in the transparent material 2. The second laser 4 scans according to a preset track, and melts the transparent material 2 and the metal material 3 of the interface to be welded in a heat conduction mode, and the heat transferred to the welding interface is not transferred to the inside of the transparent material 2 and the metal material 3, so that the melted material is instantly cooled and solidified, and finally high-quality welding of the transparent material 2 and the metal material 3 is realized.

As an alternative to this embodiment, the transparent material 2 is sapphire glass, or quartz glass, or soda lime glass, or borosilicate glass.

As an alternative to this embodiment, the metal material 3 is aluminum, or a copper alloy, or stainless steel, or a titanium alloy.

As an alternative implementation of this embodiment, the line spacing of the polishing scan performed by the first laser 1 is 0.01-0.1mm.

As an alternative implementation manner of this embodiment, the preset welding path is in a shape of "Z", or "back", or "bow", or "one".

As an alternative to this embodiment, the laser device comprises a polished laser for emitting the first laser light 1 and an ultrafast laser for emitting the second laser light 4.

As an alternative implementation of this embodiment, the ultrafast laser is a picosecond laser or a femtosecond laser.

As an alternative to this embodiment, the polishing laser is a nanosecond laser or a continuous laser.

As an alternative implementation of this embodiment, the pulse repetition frequency of the polishing laser is 20-50kHz, the output power is 50-500W, and the wavelength of the first laser is 1064nm.

As an alternative implementation manner of the embodiment, the output wavelength of the ultrafast laser is 355-1064nm, the pulse width is 50 fs-10 ps, the pulse repetition frequency is 1 kHz-100 MHz, and the output power is 1-200W.

The following are specific embodiments of the present invention:

example 1

In this embodiment, taking the transparent material 2 as sapphire and the metal material 3 as titanium alloy as examples, the sapphire is selected to have a size of about 10mm×7mm×3mm, and the titanium alloy is selected to have a size of about 30mm×20mm×5mm, and laser welding is performed according to the steps in the ultrafast laser welding method for the transparent material and the metal material provided in the above embodiment.

Wherein, the output wavelength of the first laser 1 is set to 1064nm, the output power is 100W, the pulse repetition frequency is 20kHz, and the line spacing of the first laser for polishing scanning is set to 0.03mm. The laser energy of the first laser 1 causes the titanium alloy surface layer to be melted, and the melted titanium alloy material flows under the pressure provided by the clamp and fills the concave pit 311 on the second plane to be welded 31, so that the surface of the second plane to be welded 31 tends to be flat and smooth, thereby improving the problem of poor surface smoothness of the titanium alloy;

the second laser 4 emitted by the ultrafast laser passes through the sapphire on the upper layer and then is focused on the interface to be welded, namely the joint surface between the first plane to be welded 21 and the second plane to be welded 31, and the welding mode is transmission lap welding. The pulse width of the ultrafast laser was set to 120fs, the output power was 10W, the repetition rate was 200kHz, and the output wavelength of the second laser was set to 1064nm. And a welding line is arranged on the movable machine tool and is in a straight shape, and the heated and melted sapphire and the titanium alloy are cooled and solidified in a short time, so that the welding between the titanium alloy and the sapphire is completed.

Example two

In this embodiment, taking the transparent material 2 as quartz glass and the metal material 3 as stainless steel as an example, the quartz glass is selected to have a size of about 20mm×10mm×2mm, and the stainless steel is selected to have a size of about 30mm×20mm×5mm, and laser welding is performed according to the steps in the ultrafast laser welding method for the transparent material 2 and the metal material 3 provided in the above embodiment.

Wherein, the output wavelength of the first laser 1 is set to 1064nm, the output power is 50W, the pulse repetition frequency is 20kHz, and the line spacing of the first laser 1 for polishing scanning is set to 0.05mm. The laser energy of the first laser 1 causes the stainless steel surface layer to be melted, the melted stainless steel material flows under the pressure provided by the clamp and fills the concave pits 311 on the second plane to be welded 31, so that the surface of the second plane to be welded 31 tends to be flat and smooth, thereby improving the problem of poor surface finish of the stainless steel;

the second laser 4 emitted by the ultrafast laser passes through the quartz glass on the upper layer and then is focused on the interface to be welded, namely the joint surface between the first plane to be welded 21 and the second plane to be welded 31, and the welding mode is transmission lap welding. The pulse width of the ultrafast laser was set to 150fs, the output power was 8W, the repetition rate was 200kHz, and the output wavelength of the second laser 4 was set to 1064nm. And the welding route is arranged on the movable machine tool in a bow shape, and the heated and melted quartz glass and stainless steel are cooled and solidified in a short time, so that the welding between the stainless steel and the quartz glass is completed.

The foregoing description of the preferred embodiments of the invention is not intended to be limiting, but rather is intended to cover all modifications, equivalents, and alternatives falling within the spirit and principles of the invention.

Claims

1. An ultrafast laser welding method for transparent materials and metal materials is used for welding and connecting a first plane to be welded of the transparent materials and a second plane to be welded of the metal materials, and the surface of the second plane to be welded is provided with a plurality of pits, and is characterized by comprising the following steps:

and fourthly, the laser equipment emits second laser, the second laser enables the transparent material and the metal material to be heated and melted along a preset welding path, and the welding seam is formed by cooling and forming, so that the welding connection between the first plane to be welded and the second plane to be welded is realized.

2. The ultra-fast laser welding method of a transparent material and a metal material according to claim 1, wherein the transparent material is sapphire glass, or quartz glass, or soda lime glass, or borosilicate glass.

3. The ultra-fast laser welding method of a transparent material and a metallic material according to claim 1, wherein the metallic material is aluminum, or a copper alloy, or stainless steel, or a titanium alloy.

4. The ultra-fast laser welding method for transparent materials and metal materials according to claim 1, wherein the first laser performs polishing scanning with a line spacing of 0.01-0.1mm.

5. The ultra-fast laser welding method for transparent materials and metal materials according to claim 1, wherein the preset welding path is in a shape of a Z, a back, a bow, or a straight.

6. The ultra-fast laser welding method for transparent materials and metallic materials according to claim 1, wherein the laser device comprises a polishing laser for emitting the first laser light and an ultra-fast laser for emitting the second laser light.

7. The method of ultrafast laser welding a transparent material to a metal material according to claim 6, wherein the ultrafast laser is a picosecond laser or a femtosecond laser.

8. The ultra-fast laser welding method for transparent materials and metallic materials according to claim 6, wherein the polishing laser is a nanosecond laser or a continuous laser.

9. The ultra-fast laser welding method for transparent materials and metal materials according to claim 6, wherein the pulse repetition rate of the polishing laser is 20-50kHz, the output power is 50-500W, and the wavelength of the first laser is 1064nm.

10. The ultra-fast laser welding method for transparent materials and metal materials according to claim 6, wherein the output wavelength of the ultra-fast laser is 355-1064nm, the pulse width is 50 fs-10 ps, the pulse repetition frequency is 1 kHz-100 MHz, and the output power is 1-200W.