Glass and metal laser welding method using double-layer structure solder and solder thereof

Abstract

A glass and metal laser welding method using a double-layer structure solder and its solder, the method includes: surface pretreatment, ultrasonic cleaning of the metal and glass surfaces, using pulsed laser deposition technology to sequentially deposit nano-Si and Al double-layer thin film pre-solder in the area to be welded on the glass surface; assembly, assembling the glass and metal according to the requirements of the connection joint, placing the glass solder with the pre-solder downward on the metal, and clamping the two with a clamp; nanosecond laser welding, focusing the laser on the contact surface of the thin film solder and the glass, and keeping the focus on the same plane, turning on the laser to scan and weld on the focal plane; post-welding treatment, using high-frequency nanosecond laser for post-welding heat treatment, and naturally cooling the joint after treatment. The present invention can accurately control the thermal effect generated in the tiny welding area, improve the wettability between the glass and metal interface, inhibit interface brittle compounds, and reduce thermal stress and residual stress.

Description

Technical Field

[0001] The present invention relates to the field of welding of dissimilar materials, and in particular to a glass and metal laser welding method with a double-layer structure solder and the solder. Background Art

[0002] Glass is suitable for various applications due to its transparent properties, high hardness and strength, thermal stability and corrosion resistance. Glass-to-metal connections are gaining more and more attention due to their wide applications in aerospace, optical sensors, MEMS systems, smartphones and medical fields. However, glass-to-metal connections still cannot meet the growing industrial requirements for quality, precision and efficiency.

[0003] At present, methods such as gluing, mechanical riveting, brazing, anodic bonding and laser welding are used to connect dissimilar materials between glass and metal. However, these technologies have certain limitations, which hinder their widespread application in industry. In glass and metal laser welding, it can be divided into four categories according to the laser welding mode, one of which is continuous laser welding, quasi-continuous laser welding, short pulse laser welding and ultra-short pulse laser welding. These four modes of laser welding rely on the laser thermal effect to act on metal and glass to achieve the connection between the two. The thermal effect induced by continuous laser action can easily cause serious distortion and cracking of glass. Pulsed laser can control the pulse width and peak power of the laser beam to improve the accuracy of material melting and softening during laser welding, but the cost is relatively high. At the same time, according to the welding method of the two, it can also be divided into two categories, one is direct welding of the two, and the other is welding of the two by introducing transition elements, among which the technical means include evaporation of transition elements, paste coating, foil solder placement, and addition of ion-carrying solutions. There are currently four problems in the process of introducing transition elements for welding the two: the introduced transition elements are mainly single metal elements, which leads to poor wettability on the glass side; the melting temperature of the introduced transition elements is too high, which will cause thermal stress to affect the mechanical properties of the joint; a large amount of brittle compounds are produced at the interface of the introduced transition elements; the thermal expansion coefficients of glass and the introduced transition elements are quite different, resulting in large residual stress after welding. Based on the urgent need for the connection of glass and metal, a high-quality, high-precision and high-efficiency connection that can be applied to various types of glass and metal is needed, especially for the welding of high-temperature sensitive tempered glass and metal.

[0004] The Chinese patent (CN117564390A) discloses a method for welding glass-solder-metal based on pulse train mode ultrafast laser, which is to spread paste solder on the metal surface, place glass on the paste solder, adjust the glass posture to the desired posture, and fill the gap with paste solder to perform laser welding of glass and metal; the solder used is tin-based solder, so that the glass and solder are melted and mixed, and the elements diffuse between the molten solder and the metal to achieve connection; the laser is used for welding in pulse train mode, and the laser is focused on the interface between the glass and the solder through the glass to perform laser welding of glass-solder-metal. Its disadvantages are: it is difficult to ensure the uniformity and consistency of the thickness of the paste solder, resulting in uncontrollable gaps at the interface between the glass and the metal, thereby affecting the quality of the laser welded joint; the solder is composed of a single metal element, resulting in poor bonding between the solder and the glass side, and the thermal expansion coefficients of the solder and the glass are quite different, resulting in large residual stress after welding; the cost of picosecond lasers is relatively high. Summary of the invention

[0005] The present invention aims to overcome the above-mentioned problems of the prior art and provides a glass-metal laser welding method using a double-layer structure solder and the solder thereof.

[0006] The present invention uses pulsed laser deposition technology to sequentially deposit nano-Si and Al double-layer thin films in the area to be welded to pre-set solder. The Si element is an element contained in the glass itself and is relatively friendly to the glass, so the Si element is first deposited on the glass. The deposition of the Al element can reduce the melting point of the solder and increase the wettability of the solder to the metal and glass. According to the Al-Si binary phase diagram, the eutectic point is located at about 12.6 wt% Si and a temperature of 577°C. At this composition and temperature, the liquid will directly solidify into a mixture of two solid phases: a eutectic mixture of α-aluminum solid solution and silicon. Nano-scale Al-Si solder, as a relatively low-temperature solder, is conducive to the welding of high-temperature sensitive tempered glass and metal. At the same time, the Si interface has a smaller chemical potential, and the Si element is more likely to diffuse and aggregate to the interface. This Si element will reduce the reaction rate of the interface Fe and Al elements, inhibit the interface brittle compounds, and thus improve the joint strength. Since the nanosecond laser pulse lasts for a relatively short time, the area where the material is heated by the nanosecond laser is quite limited. Therefore, it can precisely control the thermal effect generated in a tiny area and effectively control thermal stress. Heat treatment with high-frequency nanosecond laser after welding can reduce residual stress. The glass-metal laser welding method using double-layer structure solder can improve the wettability between the glass and metal interface, inhibit brittle compounds, reduce thermal stress and residual stress, and thus achieve high-quality, high-precision and high-efficiency connection between the two.

[0007] The purpose of the present invention can be achieved through the following technical solutions:

[0008] The first aspect of the present invention relates to a method for laser welding of glass and metal using a double-layer structure solder, comprising the following steps:

[0009] Step 1: Surface pretreatment: ultrasonically clean the metal and glass surfaces, and use pulsed laser deposition technology to sequentially deposit nano-Si and Al double-layer films in the area to be welded to pre-set the solder;

[0010] Step 2: Assemble the glass and metal according to the requirements of the connection joint, place the glass with pre-set solder downward on the metal, and clamp the two with a clamp;

[0011] Step 3: Nanosecond laser welding: focus the laser on the contact surface between the thin film solder and the glass, and keep the focus on the same plane. Turn on the laser to perform scanning welding on the focal plane.

[0012] Step 4: Post-weld treatment: Use high-frequency nanosecond laser for post-weld heat treatment, and allow the joint to cool naturally after treatment.

[0013] As a further solution of the present invention: in step 1, a double-layer structure of nano-Si and Al thin film solder is sequentially deposited using pulsed laser deposition technology;

[0014] As a further solution of the present invention: in step 1, the parameters of pulsed laser deposition are as follows: laser wavelength is 248nm, laser energy density is 200-400 J / cm 2 , laser frequency 40 Hz, distance between target and glass 5 cm, laser spot moving speed 10 mm / s;

[0015] The parameters of the growth atmosphere for pulsed laser deposition are as follows: gas pressure is 10~20 Pa and flow rate is 20~30 sccm.

[0016] As a further solution of the present invention: in step 1, the growth atmosphere type of pulsed laser deposition is argon.

[0017] As a further solution of the present invention: in step 1, the glass is soda-lime glass, quartz glass, silicate glass or tempered glass.

[0018] As a further solution of the present invention: in step 1, a Si film is first deposited on the glass surface, and then a nano-Al film is deposited, wherein the Si film thickness is 10-20 nm, and the Al film thickness is 7 times the Si film thickness;

[0019] As a further solution of the present invention: in step 2, the welding metal includes but is not limited to aluminum alloy, stainless steel, titanium alloy or Kovar alloy.

[0020] As a further solution of the present invention: in step 3, the process parameters of the nanosecond laser during welding are: laser wavelength 1060 nm, pulse width 270 ns, average power 85 W, pulse repetition frequency 50 kHz, scanning speed 300 mm / s;

[0021] As a further solution of the present invention: in step three, the welding area and path of the nanosecond laser during welding are: the welding area is the solder covering area and is filled in a straight line, the filling interval is 80 μm, and the path is scanned from left to right in sequence.

[0022] As a further solution of the present invention: in step 4, the process parameters of the nanosecond laser for post-welding treatment are: laser wavelength 1060 nm, pulse width 270 ns, average power 85 W, pulse repetition frequency 4000 kHz, scanning speed 300 mm / s; the welding area and path of the nanosecond laser for post-weld heat treatment are: linear filling, filling interval of 80 μm, and the path is scanned from left to right in sequence.

[0023] The second aspect of the present invention relates to a brazing material for a method of laser welding glass and metal using a double-layer brazing material, which is a double-layer film of nano-Si and Al deposited sequentially in the area to be welded on the glass surface using a pulsed laser deposition technique.

[0024] Beneficial effects of the present invention:

[0025] The joint strength of the glass and metal laser welding method using double-layer structure solder is 8.5-16.7MPa. This method can accurately control the thermal effect generated in the tiny welding area, improve the wettability between the glass and metal interface, inhibit the interface brittle compounds, and reduce thermal stress and residual stress, thereby achieving high-quality, high-precision and high-efficiency connection between the two, especially for the welding of high-temperature sensitive tempered glass and metal. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is a flow chart of the laser welding method of glass and metal with double-layer structure solder.

[0027] Figure 2 It is a schematic diagram of the laser welding method of glass and metal with double-layer structure solder.

[0028] Figure 3 This is a schematic diagram of the position relationship between the glass and metal of the double-layer structure solder.

[0029] Figure 4 This is an electron microscope photograph of the interface of the aluminum alloy and glass welding joint in Example 1.

[0030] Figure 5 This is an electron microscope photograph of the interface of the aluminum alloy and glass welding joint in Example 2.

[0031] Figure 6 This is an electron microscope photograph of the interface of the aluminum alloy and glass welding joint in Example 3. DETAILED DESCRIPTION

[0032] The technical solution of the present invention is further described below in conjunction with the accompanying drawings.

[0033] Example 1

[0034] This embodiment relates to a laser welding method for glass and metal using a double-layer structure solder, comprising the following steps:

[0035] Step 1: Surface pretreatment: The surfaces of 6061 aluminum alloy and aluminosilicate glass were ultrasonically cleaned. The laser wavelength of the glass surface was 248 nm and the laser energy density was 200 J / cm 2 , laser frequency 40 Hz, distance between Si target and Al target and glass 5 cm, laser spot moving speed 10 mm / s, argon gas pressure 10~20 Pa, flow rate 20~30 sccm pulse laser deposition technology sequentially deposits nano-Si and Al double-layer structure films in the welding area to pre-prepare solder, where the Si film thickness is 10 nm, and the Al film thickness is 7 times the Si film thickness;

[0036] Step 2, sample assembly: Assemble the glass and metal according to the requirements of the connection joint, place the aluminosilicate glass with pre-set solder downward on the 6061 aluminum alloy, and clamp the two with a clamp;

[0037] Step 3, nanosecond laser welding: The focus of the laser is placed on the contact surface between the thin film solder and the aluminosilicate glass. The welding is performed using a nanosecond pulse laser with a laser wavelength of 1060 nm, a pulse width of 270 ns, an average power of 85 W, a pulse repetition frequency of 50 kHz, and a scanning speed of 300 mm / s. The welding area is the solder-covered area and is filled in a straight line with a filling interval of 80 μm. The path is scanned from left to right in sequence.

[0038] Step 4. Post-weld treatment: Use high-frequency nanosecond laser with a laser wavelength of 1060 nm, a pulse width of 270 ns, an average power of 85 W, a pulse repetition frequency of 4000 kHz, and a scanning speed of 300 mm / s for post-weld heat treatment; the post-weld heat treatment area is filled with a straight line, the filling interval is 80 μm, and the path is scanned from left to right in sequence. After treatment, the joint is cooled naturally.

[0039] The electron microscope photo of the aluminum alloy and glass welding joint interface of this embodiment is as follows: Figure 4 As shown, by observing Figure 4It can be found that the aluminosilicate glass with double-layer solder is connected to 6061 aluminum alloy. Combined with the energy spectrometer test analysis, it can be seen that the interface of the glass-metal welding joint is composed of a mixture of Al-Si-O and Al-Si eutectic. The Al film and Si film prepared by the laser pulse deposition method melt under the laser thermal effect, and then the glass softens and reacts with the solder and aluminum alloy to achieve chemical connection.

[0040] According to the test, the room temperature shear strength of the aluminum alloy and glass welding joint of this embodiment reaches 13 MPa.

[0041] Example 2

[0042] This embodiment relates to a laser welding method for glass and metal using a double-layer structure solder, comprising the following steps:

[0043] Step 1: Surface pretreatment: The surfaces of 6061 aluminum alloy and aluminosilicate glass were ultrasonically cleaned. The laser wavelength of the glass surface was 248 nm and the laser energy density was 300 J / cm 2 , laser frequency 40 Hz, distance between Si target and Al target and glass 5 cm, laser spot moving speed 10 mm / s, argon gas pressure 10~20 Pa, flow rate 20~30 sccm pulse laser deposition technology sequentially deposits nano-Si and Al double-layer structure films in the welding area to pre-prepare solder, where the Si film thickness is 15 nm, and the Al film thickness is 7 times the Si film thickness;

[0044] Step 2, sample assembly: Assemble the glass and metal according to the requirements of the connection joint, place the aluminosilicate glass with pre-set solder downward on the 6061 aluminum alloy, and clamp the two with a clamp;

[0045] Step 3, nanosecond laser welding: The focus of the laser is placed on the contact surface between the thin film solder and the aluminosilicate glass. The welding is performed using a nanosecond pulse laser with a laser wavelength of 1060 nm, a pulse width of 270 ns, an average power of 85 W, a pulse repetition frequency of 50 kHz, and a scanning speed of 300 mm / s. The welding area is the solder-covered area and is filled in a straight line with a filling interval of 80 μm. The path is scanned from left to right in sequence.

[0046] Step 4. Post-weld treatment: Use high-frequency nanosecond laser with a laser wavelength of 1060 nm, a pulse width of 270 ns, an average power of 85 W, a pulse repetition frequency of 4000 kHz, and a scanning speed of 300 mm / s for post-weld heat treatment; the post-weld heat treatment area is filled with a straight line, the filling interval is 80 μm, and the path is scanned from left to right in sequence. After treatment, the joint is cooled naturally.

[0047] The electron microscope photo of the aluminum alloy and glass welding joint interface of this embodiment is as follows: Figure 5 As shown, by observing Figure 5 It can be found that aluminosilicate glass with double-layer structure solder is connected to 6061 aluminum alloy.

[0048] According to the test, the room temperature shear strength of the aluminum alloy and glass welding joint of this embodiment reaches 16.7 MPa.

[0049] Example 3

[0050] This embodiment relates to a laser welding method for glass and metal using a double-layer structure solder, comprising the following steps:

[0051] Step 1: Surface pretreatment: The surfaces of 6061 aluminum alloy and aluminosilicate glass were ultrasonically cleaned. The laser wavelength of the glass surface was 248 nm and the laser energy density was 400 J / cm 2 , laser frequency 40 Hz, distance between Si target and Al target and glass 5 cm, laser spot moving speed 10 mm / s, argon gas pressure 10~20 Pa, flow rate 20~30 sccm pulse laser deposition technology sequentially deposits nano-Si and Al double-layer structure films in the welding area to pre-prepare solder, where the Si film thickness is 20 nm, and the Al film thickness is 7 times the Si film thickness;

[0052] Step 2, sample assembly: Assemble the glass and metal according to the requirements of the connection joint, place the aluminosilicate glass with pre-set solder downward on the 6061 aluminum alloy, and clamp the two with a clamp;

[0053] Step 3, nanosecond laser welding: The focus of the laser is placed on the contact surface between the thin film solder and the aluminosilicate glass. The welding is performed using a nanosecond pulse laser with a laser wavelength of 1060 nm, a pulse width of 270 ns, an average power of 85 W, a pulse repetition frequency of 50 kHz, and a scanning speed of 300 mm / s. The welding area is the solder-covered area and is filled in a straight line with a filling interval of 80 μm. The path is scanned from left to right in sequence.

[0054] Step 4. Post-weld treatment: Use high-frequency nanosecond laser with a laser wavelength of 1060 nm, a pulse width of 270 ns, an average power of 85 W, a pulse repetition frequency of 4000 kHz, and a scanning speed of 300 mm / s for post-weld heat treatment; the post-weld heat treatment area is filled with a straight line, the filling interval is 80 μm, and the path is scanned from left to right in sequence. After treatment, the joint is cooled naturally.

[0055] The electron microscope photo of the aluminum alloy and glass welding joint interface of this embodiment is as follows: Figure 6 As shown, by observing Figure 6It can be found that aluminosilicate glass with double-layer structure solder is connected to 6061 aluminum alloy.

[0056] According to the test, the room temperature shear strength of the aluminum alloy and glass welding joint of this embodiment reaches 15.1 MPa.

[0057] Example 4

[0058] This embodiment relates to a laser welding method for glass and metal using a double-layer structure solder, comprising the following steps:

[0059] Step 1: Surface pretreatment: The TC4 titanium alloy and aluminosilicate glass surfaces were ultrasonically cleaned. The glass surface was cleaned with a laser wavelength of 248 nm and a laser energy density of 400 J / cm 2 , laser frequency 40 Hz, distance between Si target and Al target and glass 5 cm, laser spot moving speed 10 mm / s, argon gas pressure 10~20 Pa, flow rate 20~30 sccm pulse laser deposition technology sequentially deposits nano-Si and Al double-layer structure films in the welding area to pre-prepare solder, where the Si film thickness is 10 nm, and the Al film thickness is 7 times the Si film thickness;

[0060] Step 2, sample assembly: Assemble the glass and metal according to the requirements of the connection joint, place the aluminosilicate glass with pre-set solder downward on the TC4 titanium alloy, and clamp the two with a clamp;

[0061] Step 3, nanosecond laser welding: The focus of the laser is placed on the contact surface between the thin film solder and the aluminosilicate glass. The welding is performed using a nanosecond pulse laser with a laser wavelength of 1060 nm, a pulse width of 270 ns, an average power of 85 W, a pulse repetition frequency of 50 kHz, and a scanning speed of 300 mm / s. The welding area is the solder-covered area and is filled in a straight line with a filling interval of 80 μm. The path is scanned from left to right in sequence.

[0062] Step 4. Post-weld treatment: Use high-frequency nanosecond laser with a laser wavelength of 1060 nm, a pulse width of 270 ns, an average power of 85 W, a pulse repetition frequency of 4000 kHz, and a scanning speed of 300 mm / s for post-weld heat treatment; the post-weld heat treatment area is filled with a straight line, the filling interval is 80 μm, and the path is scanned from left to right in sequence. After treatment, the joint is cooled naturally.

[0063] After the implementation of this embodiment, the interface between the titanium alloy and the aluminosilicate glass joint was observed and it was found that Al-Ti, Ti5Si3 intermetallic compounds were generated by the reaction between the thin film solder and the titanium alloy.

[0064] According to the test, the room temperature shear strength of the TC4 titanium alloy and glass welded joint of this embodiment reaches 8.5 MPa.

[0065] Example 5

[0066] This embodiment relates to a laser welding method for glass and metal using a double-layer structure solder, comprising the following steps:

[0067] Step 1: Surface pretreatment: The TC4 titanium alloy and aluminosilicate glass surfaces were ultrasonically cleaned. The glass surface was cleaned with a laser wavelength of 248 nm and a laser energy density of 400 J / cm 2 , laser frequency 40 Hz, distance between Si target and Al target and glass 5 cm, laser spot moving speed 10 mm / s, argon gas pressure 10~20 Pa, flow rate 20~30 sccm pulse laser deposition technology sequentially deposits nano-Si and Al double-layer structure films in the welding area to pre-prepare solder, where the Si film thickness is 15 nm, and the Al film thickness is 7 times the Si film thickness;

[0068] Step 2, sample assembly: Assemble the glass and metal according to the requirements of the connection joint, place the aluminosilicate glass with pre-set solder downward on the TC4 titanium alloy, and clamp the two with a clamp;

[0069] Step 3, nanosecond laser welding: The focus of the laser is placed on the contact surface between the thin film solder and the aluminosilicate glass. The welding is performed using a nanosecond pulse laser with a laser wavelength of 1060 nm, a pulse width of 270 ns, an average power of 85 W, a pulse repetition frequency of 50 kHz, and a scanning speed of 300 mm / s. The welding area is the solder-covered area and is filled in a straight line with a filling interval of 80 μm. The path is scanned from left to right in sequence.

[0070] Step 4. Post-weld treatment: Use high-frequency nanosecond laser with a laser wavelength of 1060 nm, a pulse width of 270 ns, an average power of 85 W, a pulse repetition frequency of 4000 kHz, and a scanning speed of 300 mm / s for post-weld heat treatment; the post-weld heat treatment area is filled with a straight line, the filling interval is 80 μm, and the path is scanned from left to right in sequence. After treatment, the joint is cooled naturally.

[0071] After the implementation of this embodiment, the interface between the titanium alloy and the aluminosilicate glass joint was observed and it was found that Al-Ti, Ti5Si3 intermetallic compounds were generated by the reaction between the thin film solder and the titanium alloy.

[0072] According to the test, the room temperature shear strength of the TC4 titanium alloy and glass welded joint of this embodiment reaches 10 MPa.

[0073] Example 6

[0074] This embodiment relates to a laser welding method for glass and metal using a double-layer structure solder, comprising the following steps:

[0075] Step 1: Surface pretreatment: The TC4 titanium alloy and aluminosilicate glass surfaces were ultrasonically cleaned. The glass surface was cleaned with a laser wavelength of 248 nm and a laser energy density of 400 J / cm 2 , laser frequency 40 Hz, distance between Si target and Al target and glass 5 cm, laser spot moving speed 10 mm / s, argon gas pressure 10~20 Pa, flow rate 20~30 sccm pulse laser deposition technology sequentially deposits nano-Si and Al double-layer structure films in the welding area to pre-prepare solder, where the Si film thickness is 20 nm, and the Al film thickness is 7 times the Si film thickness;

[0076] Step 2, sample assembly: Assemble the glass and metal according to the requirements of the connection joint, place the aluminosilicate glass with pre-set solder downward on the TC4 titanium alloy, and clamp the two with a clamp;

[0077] Step 3, nanosecond laser welding: The focus of the laser is placed on the contact surface between the thin film solder and the aluminosilicate glass. The welding is performed using a nanosecond pulse laser with a laser wavelength of 1060 nm, a pulse width of 270 ns, an average power of 85 W, a pulse repetition frequency of 50 kHz, and a scanning speed of 300 mm / s. The welding area is the solder-covered area and is filled in a straight line with a filling interval of 80 μm. The path is scanned from left to right in sequence.

[0078] Step 4. Post-weld treatment: Use high-frequency nanosecond laser with a laser wavelength of 1060 nm, a pulse width of 270 ns, an average power of 85 W, a pulse repetition frequency of 4000 kHz, and a scanning speed of 300 mm / s for post-weld heat treatment; the post-weld heat treatment area is filled with a straight line, the filling interval is 80 μm, and the path is scanned from left to right in sequence. After treatment, the joint is cooled naturally.

[0079] After the implementation of this embodiment, the interface between the titanium alloy and the aluminosilicate glass joint was observed and it was found that Al-Ti, Ti5Si3 intermetallic compounds were generated by the reaction between the thin film solder and the titanium alloy.

[0080] According to the test, the room temperature shear strength of the TC4 titanium alloy and glass welded joint of this embodiment reaches 7.9 MPa.

[0081] Example 7

[0082] This embodiment relates to a laser welding method for glass and metal using a double-layer structure solder, comprising the following steps:

[0083] Step 1: Surface pretreatment: The surfaces of 304 stainless steel and aluminosilicate glass were ultrasonically cleaned. The laser wavelength of the glass surface was 248 nm and the laser energy density was 400 J / cm 2 , laser frequency 40 Hz, distance between Si target and Al target and glass 5 cm, laser spot moving speed 10 mm / s, argon gas pressure 10~20 Pa, flow rate 20~30 sccm pulse laser deposition technology sequentially deposits nano-Si and Al double-layer structure films in the welding area to pre-prepare solder, where the Si film thickness is 15 nm, and the Al film thickness is 7 times the Si film thickness;

[0084] Step 2, sample assembly: Assemble the glass and metal according to the requirements of the connection joint, place the aluminosilicate glass with pre-set solder downward on the 304 stainless steel, and clamp the two with a clamp;

[0085] Step 3, nanosecond laser welding: The focus of the laser is placed on the contact surface between the thin film solder and the aluminosilicate glass. The welding is performed using a nanosecond pulse laser with a laser wavelength of 1060 nm, a pulse width of 270 ns, an average power of 85 W, a pulse repetition frequency of 50 kHz, and a scanning speed of 300 mm / s. The welding area is the solder-covered area and is filled in a straight line with a filling interval of 80 μm. The path is scanned from left to right in sequence.

[0086] Step 4. Post-weld treatment: Use high-frequency nanosecond laser with a laser wavelength of 1060 nm, a pulse width of 270 ns, an average power of 85 W, a pulse repetition frequency of 4000 kHz, and a scanning speed of 300 mm / s for post-weld heat treatment; the post-weld heat treatment area is filled with a straight line, the filling interval is 80 μm, and the path is scanned from left to right in sequence. After treatment, the joint is cooled naturally.

[0087] After the implementation of this embodiment, the interface between the stainless steel and the aluminosilicate glass joint was observed and it was found that Fe-Al intermetallic compounds were generated by the reaction between the film solder and the stainless steel.

[0088] According to the test, the room temperature shear strength of the 304 stainless steel and glass welding joint of this embodiment reaches 10.2 MPa.

[0089] Example 8

[0090] This embodiment relates to a solder for a glass-metal laser welding method using a double-layer structure solder of one of embodiments 1 to 8, which is a nano-Si and Al double-layer film sequentially laser-deposited on the glass surface in the area to be welded using a pulsed laser deposition technique.

[0091] The contents described in the embodiments of this specification are merely an enumeration of the implementation forms of the inventive concept. The protection scope of the present invention should not be regarded as limited to the specific forms described in the embodiments. The protection scope of the present invention also extends to equivalent technical means that can be conceived by those skilled in the art based on the inventive concept.

Claims

1. A laser welding method for glass and metal using a double-layer structure solder comprises the following steps: Step 1: Surface pretreatment: ultrasonically clean the metal and glass surfaces, and use pulsed laser deposition technology to deposit nano-Si and Al double-layer films on the glass surface in the area to be welded to pre-set solder; Step 2, sample assembly: Assemble the glass and metal according to the requirements of the connection joint, place the glass with pre-set solder downward on the metal, and clamp the two with a clamp; Step 3: Nanosecond laser welding: Focus the laser on the contact surface between the thin film solder and the glass, and keep the focus on the same plane. Turn on the laser to perform scanning welding on the focal plane. Step 4: Post-welding treatment: Use high-frequency nanosecond laser for post-weld heat treatment, and the joint will cool naturally after treatment.

2. The method for laser welding of glass and metal using double-layer solder according to claim 1, characterized in that: The glass surface in step 1 uses pulsed laser deposition technology to sequentially deposit nano-Si and Al double-layer thin film pre-solder in the area to be welded, including: sequentially depositing nano-Si and Al thin film solder double-layer structure using pulsed laser deposition technology; The parameters of the pulsed laser deposition are as follows: laser wavelength is 248 nm, laser energy density is 200-400 J / cm 2 , laser frequency 40 Hz, distance between target and glass 5 cm, laser spot moving speed 10 mm / s; the parameters of the growth atmosphere of the pulsed laser deposition are as follows: gas pressure is 10~20 Pa, flow rate is 20~30 sccm; The target materials used in the pulse laser deposition are Si target material and Al target material.

3. The method for laser welding of glass and metal using double-layer solder according to claim 2, characterized in that: The growth atmosphere type of the pulse laser deposition is argon.

4. The method for laser welding of glass and metal using double-layer solder according to claim 1, characterized in that: The glass is soda-lime glass, quartz glass, silicate glass or tempered glass.

5. The method for laser welding of glass and metal using double-layer solder according to claim 1, characterized in that: In step 1, a Si film is first deposited on the glass surface, and then a nano-Al film is deposited, wherein the thickness of the Si film is 10-20 nm, and the thickness of the Al film is 7 times the thickness of the Si film.

6. The method for laser welding of glass and metal using double-layer solder according to claim 1, characterized in that: The metal in step 2 includes aluminum alloy, stainless steel, titanium alloy or Kovar alloy.

7. The method for laser welding of glass and metal using a double-layer solder according to claim 1, characterized in that: In step three, the process parameters of nanosecond laser during welding are: laser wavelength 1060 nm, pulse width 270 ns, average power 85 W, pulse repetition frequency 50 kHz, and scanning speed 300 mm / s.

8. The method for laser welding of glass and metal using double-layer solder according to claim 1, characterized in that: In step three, the welding area and path of the nanosecond laser during welding are as follows: the welding area is the solder-covered area and is filled in a straight line, the filling interval is 80 μm, and the path is scanned from left to right in sequence.

9. The method for laser welding of glass and metal using double-layer solder according to claim 1, characterized in that: The process parameters of the post-processing nanosecond laser in step 4 are: laser wavelength 1060 nm, pulse width 270 ns, average power 85 W, pulse repetition frequency 4000 kHz, scanning speed 300 mm / s; the welding area and path of the post-weld heat treatment nanosecond laser are: linear filling, the filling interval is 80 μm, and the path is scanned from left to right in sequence.

10. The solder used in the glass-metal laser welding method using a double-layer solder according to claim 1, characterized in that: The nano-Si and Al double-layer films are deposited in sequence on the glass surface in the area to be welded using pulsed laser deposition technology.

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