A Decoupling Method for Measuring Deformation in Glass-Metal Welding

Abstract

This invention discloses a decoupled method for measuring deformation during glass-metal welding. The method includes the following steps: S1: pretreatment of the material to be welded; S2: coating the glass surface; S3: fixing the material to be welded; S4: installing and debugging the measuring instrument; S5: establishing a spatial coordinate system; S6: acquiring positional features before welding; S7: ultrafast laser welding of the glass and metal base; S8: analyzing and calculating displacement characteristics during the welding process; S9: analyzing and calculating angular characteristics during the welding process; S10: analyzing and calculating the deformation of the glass and metal during welding. This invention provides a decoupled method for measuring deformation during glass-metal welding, employing an in-situ deformation measurement device with a single camera and a single autocollimator. Simultaneously with ultrafast laser welding of the glass and metal, the deformation of the glass is monitored and measured in real time. A dual-feature-point method is used to decouple the displacement of the glass during the welding process, obtaining the displacement of the glass in five degrees of freedom during welding.

Description

Technical Field

[0001] This invention belongs to the field of ultrafast laser welding technology, and particularly relates to a decoupling method for measuring deformation in glass-metal welding. Background Technology

[0002] Glass is an optical functional material with excellent chemical, physical, and optical properties. It is commonly used as optical windows or as lenses, prisms, and mirrors for imaging. However, the inherent limitations of glass as a hard and brittle material, such as low ductility, poor impact resistance, and difficulty in processing, necessitate the joining of glass panes to form more complex structures or the connection of glass to metal substrates to improve the overall mechanical performance of the system. This has led to its widespread application in high-tech fields such as microelectronics, aerospace, automotive manufacturing, and biomedicine.

[0003] Currently, the most widely used methods for joining glass and metal include mechanical joining and adhesive joining. Mechanical joining requires additional connection interface design and precision manufacturing to ensure assembly accuracy; adhesives are convenient to use but are prone to aging, creep, and leakage, making them unsuitable for complex working environments; other diffusion joining methods, such as anodic bonding and mating sealing, require large-area, long-term heating, leading to mismatches in physical properties such as thermal expansion coefficients, which can introduce stress and cracks, and also have poor spatial selectivity. Conventional brazing is also unsuitable for joining glass and metal, requiring the selection of active brazing filler metals with good wettability for the glass and metal being joined. This limits the types of glass and metal that can be joined, and brazing is generally performed in a furnace, requiring long-term overall heating. Laser welding is an excellent method that melts materials by localizing their heating to achieve a connection. Traditional long-pulse lasers rely on linear absorption, resulting in a large heat-affected zone that is prone to cracking and requires matching of the physical properties of the glass and metal. In contrast, ultrafast lasers have advantages such as small thermal effects and high processing precision, which can effectively avoid the problems of thermal damage, thermal stress accumulation, and defects that exist in long-pulse laser processing. They can now achieve the connection of various types of glass and metal.

[0004] In ultrafast laser welding of glass and metal, residual stress and deformation are unavoidable due to non-uniform heating and cooling on both temporal and spatial scales, as well as differences in spacing and surface roughness at the weld interface. This reduces the strength and mechanical properties of the composite structure and affects the dimensional accuracy and optical performance of the components. Researching the welding deformation of structures is of significant theoretical and engineering value for improving welding processes to reduce welding stress and post-weld deformation, enhancing the load-bearing capacity of structures, and maintaining the optical performance of devices.

[0005] Currently, measurement methods used for welding deformation assessment mainly include contact measurement and non-contact optical measurement methods. Traditional measurement methods using contact sensors such as strain gauges and displacement sensors are limited in their application because they cannot fully approach the welding interface area, and the measuring points can easily obstruct the welding trajectory of the laser, making it impossible to measure the full-field deformation of the weld. Non-contact measurement methods mainly include three-dimensional laser scanning and digital image correlation (DIC). Three-dimensional laser scanning can only measure static targets; for the three-dimensional dynamic process of welding deformation, it can only acquire partial static morphology, failing to meet the requirement for rich measurement results. Digital image correlation is currently difficult to achieve real-time measurement due to limitations in speckle fabrication, camera image clarity, and software algorithm accuracy. Although many measurement methods are used for welding deformation assessment, none have achieved satisfactory results. Further research is needed in the field of ultrafast laser welding to develop more suitable methods for measuring ultrafast laser welding deformation. Summary of the Invention

[0006] The purpose of this invention is to overcome the above-mentioned problems in the prior art and provide a decoupling method for measuring deformation in glass-metal welding. The method uses an in-situ deformation measurement device with a single camera and a single autocollimator to monitor and measure the deformation of the glass in real time while ultrafast laser welding of glass-metal. The method of dual feature points is used to decouple the displacement of the glass during the welding process, and the displacement of the glass in five degrees of freedom during the welding process is obtained.

[0007] To achieve the above-mentioned technical objectives and effects, the present invention is implemented through the following technical solution:

[0008] A decoupling method for measuring deformation during glass-metal welding, comprising the following steps:

[0009] S1: Pretreatment of materials to be welded

[0010] The glass and metal base to be welded are pre-treated before welding and then ready for use.

[0011] S2: Glass surface coating

[0012] An auxiliary film is coated on two adjacent sides of the glass, marked as the first coating surface and the second coating surface. Two cross marks are engraved on the first coating surface as feature points, marked as points A and B.

[0013] S3: Welding preparation of materials to be welded

[0014] Fix the metal base to the processing platform, and then place the glass on top of the metal base;

[0015] S4: Installation and commissioning of measuring instruments

[0016] An autocollimator and a camera are set up on the processing platform, with the camera aligned with the first coating surface and the autocollimator aligned with the second coating surface. The camera height is adjusted so that the camera can clearly observe the two feature points. The autocollimator height is adjusted so that the autocollimator can receive the crosshair spot signals of the two crosshairs emitted by the autocollimator to the second coating surface and reflected back. After the adjustment is completed, the positions of the autocollimator and the camera are fixed.

[0017] S5: Establishment of a spatial coordinate system

[0018] A spatial coordinate system is constructed by selecting a point on the glass as the origin. This point is marked as point O. Point O pointing upwards is used as the z-axis of the spatial coordinate system. The x-axis of the spatial coordinate system is parallel to the optical axis of the camera, and the y-axis of the spatial coordinate system is parallel to the optical axis of the autocollimator.

[0019] S6: Acquisition of positional features before welding

[0020] Obtain the initial angular features of points A and B on the glass before welding on the autocollimator, and label them as α0 and γ0, respectively.

[0021] Based on the spatial coordinate system constructed in S5, the initial position coordinates of points A and B are obtained through measurement, denoted as A0(X). A0 Y A0 Z A0 ), B0(X B0 Y B0 Z B0 );

[0022] S7: Ultrafast laser welding of glass and metal substrates

[0023] With the camera and autocollimator on, use an ultrafast laser to focus through the glass onto the contact surface between the metal base and the glass for welding.

[0024] The camera was used to measure the positional characteristics of points A and B on the glass in real time during the welding process.

[0025] An autocollimator was used to measure the angular characteristic data of the glass in real time during the welding process, and these data were labeled as α1 and γ1.

[0026] S8: Analysis and Calculation of Displacement Characteristics During Welding

[0027] After welding, the positional feature data is analyzed and calculated to obtain the changes in the positional features of point A along the y-axis and z-axis of the spatial coordinate system, and the changes in the positional features of point B along the y-axis and z-axis of the spatial coordinate system, denoted as ΔY. A ΔZ A and ΔY B ΔZ B;

[0028] S9: Analysis and Calculation of Angular Characteristics During Welding

[0029] After the welding operation, the angle feature data in step S7 and the initial angle feature in step S6 are processed to obtain the angle feature changes of points A and B on the autocollimator during the welding operation, and are marked as Δα and Δγ.

[0030] S10: Analyze and calculate the deformation during glass-to-metal welding.

[0031] By coupling the glass rotation observed by the autocollimator with the translation of point O during the welding process, the displacement of the surface feature point observed by the camera is formed. Then, the displacement is calculated by the spatial rotation matrix. Using the initial position coordinates of points A and B, the changes in the glass rotation around point O during the welding process compared to before welding can be obtained. These are the glass angular deformations during welding, denoted as α, β, and γ. The changes in the displacement of point O during welding compared to before welding can also be obtained. These are the glass displacement deformations during welding, denoted as Δy and Δz.

[0032] Furthermore, in step S1, the main process of the pre-welding treatment is as follows: cleaning and drying the glass, and polishing the metal base.

[0033] Furthermore, in step S2, the auxiliary film is an aluminum film or a copper film.

[0034] Furthermore, in step S4, the camera is a CCD camera.

[0035] Furthermore, in step S8, the specific process of the analysis and calculation is as follows:

[0036] Step S81: Based on the spatial coordinate system constructed in step S5, analyze the position feature data to obtain the coordinate changes of point A on the y-axis and z-axis of the spatial coordinate system during the welding process, and the coordinate changes of point B on the y-axis and z-axis of the spatial coordinate system, respectively labeled as Y... A1 Z A1 and Y B1 Z B1 ;

[0037] Step S82: Based on the initial position coordinates of points A and B in step S6, obtain the initial coordinate values ​​of point A on the y-axis and z-axis of the spatial coordinate system, and the initial coordinate values ​​of point B on the y-axis and z-axis of the spatial coordinate system, respectively. A0 Z A0 and Y B0 Z B0 ;

[0038] Step S83: Analyze and calculate the changed coordinate values ​​and the initial coordinate values ​​to obtain the changes in the positional characteristics of point A along the y-axis and z-axis of the spatial coordinate system, and the changes in the positional characteristics of point B along the y-axis and z-axis of the spatial coordinate system, denoted as ΔY. A ΔZ A and ΔY B ΔZ B .

[0039] Furthermore, the specific calculation process for the deformation during glass-metal welding in step S10 is as follows:

[0040] S101: Set the changes in the glass rotation around point O during the welding process and before welding as α, β, γ, and set the changes in the displacement of point O during the welding process and before welding as Δy, Δz.

[0041] S102: During the welding process, the glass rotation observed by the autocollimator coupled with the translation of point O to form the displacement of the surface feature points observed by the camera. The total displacements of feature points A and B are respectively labeled as follows: The calculation formula is as follows:

[0042]

[0043]

[0044] in, Let A be the displacement caused by rotating around point O. Let B be the displacement caused by rotating around point O. Let A be the displacement of point A as it translates with point O. Let B be the displacement of point B as it translates with point O.

[0045] S103: Multiply each vector matrix successively to obtain the spatial rotation matrix [R]. XYZ ], spatial rotation matrix [R XYZ The calculation formula for ] is as follows:

[0046]

[0047] S103: Given the initial coordinates of points A and B, respectively A0(X) A0 Y A0 Z A0 ), B0(X B0 Y B0 Z B0 ), using the spatial rotation matrix [R XYZ Calculate the displacement of point A when it rotates around point O. The displacement caused by the rotation of point B around point O The calculation formula is as follows:

[0048]

[0049]

[0050] Since the displacement of any point on the glass is the same as the translation of point O, we have:

[0051]

[0052] The changes in the glass's rotation around point O during the welding process compared to before welding, α, β, and γ, and the changes in the displacement of point O during the welding process compared to before welding, Δy and Δz, can be calculated using the following formulas:

[0053] α = Δα;

[0054]

[0055] γ = Δγ;

[0056] Δy=ΔY A -[X A0 sinαcosβ+Y A0 (sinαsinβsinγ+cosαcosγ-1)+Z A0 (sinαsinβcosγ-cosαsinγ)];

[0057] Δz=ΔZ A -[-X A0 sinβ+Y A0 cosβsinγ+Z A0 (cosβcosγ-1)].

[0058] Compared with the prior art, the beneficial effects of the present invention are:

[0059] 1. This invention measures the deformation of glass and metal in ultrafast laser welding by using an in-situ deformation measurement device with a single camera and a single autocollimator. The measurement device does not come into contact with the glass and metal base and will not interfere with the ultrafast laser processing.

[0060] 2. This invention can monitor deformation data in real time during the ultrafast laser welding process of glass and metal, and can conveniently and quickly monitor and measure the deformation of glass in real time.

[0061] 3. The glass-metal welding deformation measurement decoupling method provided by the present invention uses a dual feature point method to decouple the displacement of the glass during the welding process, and obtains the displacement of the glass in five degrees of freedom during the welding process, thereby obtaining the deformation amount during the glass-metal welding process.

[0062] 4. The glass-metal welding deformation measurement decoupling method provided by the present invention can obtain deformation information in real time during the glass-metal welding process, which can be used to improve the welding process. Attached Figure Description

[0063] The accompanying drawings, which are included to provide a further understanding of the invention and form part of this application, illustrate exemplary embodiments of the invention and, together with their description, serve to explain the invention and do not constitute an undue limitation thereof. In the drawings:

[0064] Figure 1 This is a schematic diagram of the decoupling method for measuring glass-metal welding deformation provided by the present invention;

[0065] Figure 2 This is a flowchart of the glass-metal welding deformation measurement decoupling method provided by the present invention.

[0066] The attached figures are labeled as follows: 1. Glass; 2. Metal base; 3. Camera; 4. Autocollimator. Detailed Implementation

[0067] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0068] Example

[0069] like Figures 1 to 2 As shown, a decoupling method for measuring deformation during glass-metal welding includes the following steps:

[0070] S1: Pretreatment of materials to be welded

[0071] Clean the glass to be welded. The cleaning method can be ultrasonic cleaning or cleaning with solvents such as alcohol and acetone to remove oil stains from the glass surface. Grind the metal base to remove the processing burrs on the surface of the metal base. After the glass and metal base are processed, set them aside for use.

[0072] S2: Glass surface coating

[0073] An auxiliary film is coated on two adjacent sides of the glass, marked as the first coating surface and the second coating surface. Two cross marks are engraved on the first coating surface as feature points, marked as points A and B.

[0074] Among them, the auxiliary film is an aluminum film or a copper film, which is coated on the glass and serves as a mirror reflection optical path for the autocollimator.

[0075] S3: Welding preparation of materials to be welded

[0076] Fix the metal base to the processing platform, and then place the glass on top of the metal base;

[0077] In this process, the edge of the metal base is fixed on the processing platform to keep the metal, camera, and measuring devices such as autocollimator relatively stationary, thereby ensuring that the relative displacement observed by the instrument is generated by the relative displacement between the glass and the metal.

[0078] S4: Installation and commissioning of measuring instruments

[0079] An autocollimator and a camera are set up on the processing platform, with the camera aligned with the first coating surface and the autocollimator aligned with the second coating surface. The camera height is adjusted so that it is aligned with the feature point. The autocollimator height is adjusted so that it can receive the crosshair spot signals of the two crosshairs emitted by the autocollimator to the second coating surface and reflected back. After the adjustment is completed, the positions of the autocollimator and the camera are fixed.

[0080] The camera is a CCD camera, and the optical axis of the camera is perpendicular to the optical axis of the autocollimator.

[0081] In actual installation and debugging, the glass position can also be adjusted to adapt to the installation position of the testing instrument in step S4.

[0082] S5: Establishment of a spatial coordinate system

[0083] A spatial coordinate system is constructed by selecting a point on the glass as the origin. This point is marked as point O. Point O pointing upwards is used as the z-axis of the spatial coordinate system. The x-axis of the spatial coordinate system is parallel to the optical axis of the camera, and the y-axis of the spatial coordinate system is parallel to the optical axis of the autocollimator.

[0084] S6: Acquisition of positional features before welding

[0085] Obtain the initial angular features of points A and B on the glass before welding on the autocollimator, and label them as α0 and γ0, respectively.

[0086] Based on the spatial coordinate system constructed in S5, the initial position coordinates of points A and B are obtained through measurement, denoted as A0(X). A0 Y A0 Z A0 ), B0(X B0 Y B0 Z B0 );

[0087] S7: Ultrafast laser welding of glass and metal substrates

[0088] With the camera and autocollimator on, use an ultrafast laser to focus through the glass onto the contact surface between the metal base and the glass for welding.

[0089] The camera was used to measure the positional characteristics of points A and B on the glass in real time during the welding process.

[0090] An autocollimator was used to measure the angular characteristic data of the glass in real time during the welding process, and these data were labeled as α1 and γ1.

[0091] S8: Analysis and Calculation of Displacement Characteristics During Welding

[0092] After welding, the positional feature data are analyzed and calculated to obtain the changes in the positional features of point A along the y-axis and z-axis in the spatial coordinate system, as well as the changes in the positional features of point B along the y-axis and z-axis in the spatial coordinate system, expressed as ΔY. A ΔZ A and ΔY B ΔZ B ;

[0093] The specific process of analysis and calculation is as follows:

[0094] Step S81: Based on the spatial coordinate system constructed in step S5, analyze the position feature data to obtain the coordinate changes of point A on the y-axis and z-axis of the spatial coordinate system during the welding process, and the coordinate changes of point B on the y-axis and z-axis of the spatial coordinate system, respectively labeled as Y... A1 Z A1 and Y B1 Z B1 ;

[0095] Step S82: Based on the initial position coordinates of points A and B in step S6, obtain the initial coordinate values ​​of point A on the y-axis and z-axis of the spatial coordinate system, and the initial coordinate values ​​of point B on the y-axis and z-axis of the spatial coordinate system, respectively. A0 Z A0 and Y B0 Z B0 ;

[0096] Step S83: Analyze and calculate the changed coordinate values ​​and the initial coordinate values ​​to obtain the changes in the positional characteristics of point A along the y-axis and z-axis of the spatial coordinate system, and the changes in the positional characteristics of point B along the y-axis and z-axis of the spatial coordinate system, denoted as ΔY. A ΔZ A and ΔY B ΔZ B ;

[0097] S9: Analysis and Calculation of Angular Characteristics During Welding

[0098] After the welding operation, the angle feature data in step S7 and the initial angle feature in step S6 are processed to obtain the angle feature changes of points A and B on the autocollimator during the welding operation, and are marked as Δα and Δγ.

[0099] S10: Analyze and calculate the deformation during glass-to-metal welding.

[0100] By coupling the glass rotation observed by the autocollimator with the translation of point O during the welding process, the displacement of the surface feature point observed by the camera is formed. Then, the displacement is calculated by the spatial rotation matrix. Using the initial position coordinates of points A and B, the change in the glass rotation around point O during the welding process compared to before welding can be obtained. This is the glass angular deformation during the welding process, denoted as α, β, and γ. The change in the displacement of point O during the welding process compared to before welding can be obtained. This is the glass displacement deformation during the welding process, denoted as Δy and Δz.

[0101] The specific calculation process for step S10 is as follows:

[0102] S101: Set the changes in the glass rotation around point O during the welding process and before welding as α, β, γ, and set the changes in the displacement of point O during the welding process and before welding as Δy, Δz.

[0103] S102: During the welding process, the glass rotation observed by the autocollimator coupled with the translation of point O to form the displacement of the surface feature points observed by the camera. The total displacements of feature points A and B are respectively labeled as follows: The calculation formula is as follows:

[0104]

[0105]

[0106] in, Let A be the displacement caused by rotating around point O. Let B be the displacement caused by rotating around point O. Let A be the displacement of point A as it translates with point O. Let B be the displacement of point B as it translates with point O.

[0107] S103: Multiply each vector matrix successively to obtain the spatial rotation matrix [R]. XYZ ], spatial rotation matrix [R XYZ The calculation formula for ] is as follows:

[0108]

[0109] S103: Given the initial coordinates of points A and B, respectively A0(X) A0 Y A0 Z A0 ), B0(X B0 Y B0 Z B0 ), using the spatial rotation matrix [R XYZ Calculate the displacement of point A when it rotates around point O. The displacement caused by the rotation of point B around point O The calculation formula is as follows:

[0110]

[0111]

[0112] Since the displacement of any point on the glass is the same as the translation of point O, we have:

[0113]

[0114] The changes in the glass's rotation around point O during the welding process compared to before welding, α, β, and γ, and the changes in the displacement of point O during the welding process compared to before welding, Δy and Δz, can be calculated using the following formulas:

[0115] α = Δα;

[0116]

[0117] γ = Δγ;

[0118] Δy=ΔY A -[X A0 sinαcosβ+Y A0 (sinαsinβsinγ+cosαcosγ-1)+Z A0 (sinαsinβcosγ-cosαsinγ)];

[0119] Δz=ΔZ A -[-X A0 sinβ+Y A0 cosβsinγ+Z A0 (cosβcosγ-1)].

[0120] This embodiment provides a decoupled method for measuring deformation during glass-metal welding, enabling real-time in-situ deformation measurement of the ultrafast laser welding process between glass and metal, unaffected by the welding process. This embodiment employs a non-contact optical measurement method, avoiding contact with the workpiece under test and preventing interference with the ultrafast laser processing. With only four degrees of freedom in the measurement input data, this invention innovatively uses a double crosshair feature point method to obtain the welding deformation of glass across five degrees of freedom.

[0121] The following section provides further explanation using a specific deformation measurement experiment during the glass-to-metal welding process. The experimental steps for decoupling the deformation measurement during glass-to-metal welding are as follows:

[0122] Step 1: Pretreatment of materials to be welded

[0123] 2mm thick stainless steel sheet and K9 glass with a size of 20mm×20mm×35mm were selected as the materials to be welded. Sandpaper was used to remove the burrs on the surface of the stainless steel sheet caused by processing and cutting.

[0124] After removal, the stainless steel sheet and K9 glass are ultrasonically cleaned for 5 minutes. After cleaning, the stainless steel sheet and K9 glass are dried.

[0125] Step 2: Apply aluminum film to two adjacent sides of the dried K9 glass and mark them as the first coating surface and the second coating surface. Use an ultrafast laser to process a cross mark at the centroid projection of the first coating surface and mark it as point B. Process a cross mark A 10mm directly above the cross mark B as the camera observation point and mark it as point A. After the coating and marking are completed, ultrasonically clean the K9 glass again for 5 minutes and then dry it.

[0126] Step 3: Place the autocollimator and camera vertically on the processing platform, that is, the optical axes of the autocollimator and camera are perpendicular, and fix the autocollimator and camera with screws;

[0127] Fix the stainless steel sheet to the processing platform with screws at the four corners. Align the glass to be welded with the geometric center of the stainless steel sheet and place it naturally on the stainless steel sheet. Align the first coating surface with the camera and the second coating surface with the autocollimator. Adjust the glass position so that the autocollimator can receive the crosshair spot signal. Even if the autocollimator can receive the crosshair spot signal of the two crosshairs emitted by the autocollimator to the second coating surface and reflected back, the camera can clearly observe the double crosshair image on the glass surface.

[0128] Step 4: Construct a spatial coordinate system with the center of mass of the glass as the origin. Mark the initial position of the center of mass of the glass as point O. Point O points upward as the z-axis of the spatial coordinate system. The x-axis of the spatial coordinate system is parallel to the optical axis of the camera, and the y-axis of the spatial coordinate system is parallel to the optical axis of the autocollimator.

[0129] The initial coordinates of points A and B on the coated glass before welding are A0 = (X... A0 ,Y A0 Z A0 )=(10,0,10), B0=(X B0 ,Y B0 Z B0 ) = (10,0,0), unit mm;

[0130] Obtain the initial angular characteristics α0=0” and γ0=0” of the coated glass on the autocollimator before welding, as well as the initial position characteristics Y of points A and B. A0 =0mm, Z A0 =10.00mm, Y B0 =0mm, Z B0 =0mm;

[0131] Step 5: Using an 8ps pulse width ultrafast laser with a power of 4.35W, a pulse repetition frequency of 400kHz, and a scanning speed of 1000mm / s, focus on the contact surface between the glass and the stainless steel sheet, and perform a spiral scan with a spacing of 0.01mm on a 3mm×3mm area to be welded, so that the stainless steel sheet and the glass can be reliably bonded. Before and after welding, keep the camera and autocollimator on to measure the rotation data of the glass and the displacement of points A and B in real time during the welding process.

[0132] The angular characteristics of the coated glass on the autocollimator after welding were obtained: α1 = 2°, γ1 = 1°.

[0133] Based on the spatial coordinate system established in step 4, obtain the post-weld position features Y of the two crosshairs at points A and B. A1 =0.012mm, Z A1 =10.007mm, Y B1 =0.011mm, Z B1 =0.009mm;

[0134] Compare the angular characteristics of the coated glass on the autocollimator and the positional characteristics of the crosshairs before and after the welding operation. The changes in angular characteristics are Δα = 2° and Δγ = 1°.

[0135] Based on the initial position features of points A and B in the spatial coordinate system constructed in step 4, obtain the change value ΔY of the position features of the two crosshairs at points A and B. A =12μm, ΔZ A =7μm, ΔY B =11μm, ΔZ B =9μm;

[0136] Substituting the known quantities into the formula, the deformation of the glass during ultrafast laser welding is finally calculated. The specific calculation formula is as follows:

[0137] The amount of rotation of the glass center of mass about point O:

[0138] α = Δα = 2°;

[0139] γ = Δγ = 1°;

[0140]

[0141] Translation of the glass centroid O:

[0142] Δy=ΔY A -[X A0 sinαcosβ+Y A0 (sinαsinβsinγ+cosαcosγ-1)+Z A0 (sinαsinβcosγ-cosαsinγ)]=0.16597mm;

[0143] Δz=ΔZ A -[-X A0 sinβ+Y A0 cosβsinγ+Z A0 (cosβcosγ-1)]=0.10667mm.

[0144] Through experiments measuring deformation during glass-to-metal welding, it can be seen that the decoupled method for measuring glass-to-metal welding deformation is effectively used for measuring glass deformation during the glass-to-metal welding process. With only four degrees of freedom in the measurement input data, the displacement of the glass in five degrees of freedom during the glass-to-metal welding process was obtained. The optical non-contact measurement method using a single camera and a single autocollimator avoids contact with the workpiece and does not affect the welding process. Since the camera and autocollimator are always on during the welding process, the deformation of the glass during glass-to-metal welding can be monitored and measured in real time. Through data analysis and calculation, real-time processing deformation information can be obtained, allowing for improvements in the welding process based on this information.

[0145] In the description of this specification, references to terms such as "an embodiment," "example," "specific example," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0146] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the claimed invention.

Claims

1. A decoupling method for measuring deformation during glass-metal welding, characterized in that: The method includes the following steps: S1: Pretreatment of materials to be welded The glass and metal base to be welded are pre-treated before welding and then ready for use. S2: Glass surface coating An auxiliary film is coated on two adjacent sides of the glass, marked as the first coating surface and the second coating surface. Two cross marks are engraved on the first coating surface as feature points, marked as points A and B. S3: Fix the material to be welded Fix the metal base to the processing platform, and then place the glass on top of the metal base; S4: Install and debug measuring instruments An autocollimator and a camera are set up on the processing platform, with the camera aligned with the first coating surface and the autocollimator aligned with the second coating surface. The camera height is adjusted so that the camera can clearly observe the two feature points. The autocollimator height is adjusted so that the autocollimator can receive the crosshair spot signals of the two crosshairs emitted by the autocollimator to the second coating surface and reflected back. After the adjustment is completed, the positions of the autocollimator and the camera are fixed. S5: Establish a spatial coordinate system A spatial coordinate system is constructed by selecting a point on the glass as the origin. This point is marked as point O. Point O pointing upwards is used as the z-axis of the spatial coordinate system. The x-axis of the spatial coordinate system is parallel to the optical axis of the camera, and the y-axis of the spatial coordinate system is parallel to the optical axis of the autocollimator. S6: Obtain position features before welding Obtain the initial angular features of points A and B on the glass before welding on the autocollimator, and label them as α0 and γ0, respectively. According to the spatial coordinate system constructed in S5, the initial position coordinates of the A point and the B point are obtained by measurement, denoted as A0(X A0 , Y A0 , Z A0 ) and B0(X B0 , Y B0 , Z B0 ). S7: Ultrafast laser welding of glass and metal substrate With the camera and autocollimator on, use an ultrafast laser to focus through the glass onto the contact surface between the metal base and the glass for welding. The camera was used to measure the positional characteristics of points A and B on the glass in real time during the welding process. An autocollimator was used to measure the angular characteristic data of the glass in real time during the welding process, and these data were labeled as α1 and γ1. S8: Analyze and calculate the displacement characteristics during the welding process. After welding, the positional feature data is analyzed and calculated to obtain the changes in the positional features of point A along the y-axis and z-axis of the spatial coordinate system, and the changes in the positional features of point B along the y-axis and z-axis of the spatial coordinate system, denoted as ΔY. A ΔZ A and ΔY B ΔZ B ; S9: Analyze and calculate the angular characteristics during the welding process After the welding operation, the angle feature data in step S7 and the initial angle feature in step S6 are processed to obtain the angle feature changes of points A and B on the autocollimator during the welding operation, and are marked as Δα and Δγ. S10: Analyze and calculate the deformation during glass-to-metal welding. By coupling the glass rotation observed by the autocollimator with the translation of point O during the welding process, the displacement of the surface feature point observed by the camera is formed. Then, the displacement is calculated by the spatial rotation matrix. Using the initial position coordinates of points A and B, the changes in the glass rotation around point O during the welding process compared to before welding can be obtained. These are the glass angular deformations during welding, denoted as α, β, and γ. The changes in the displacement of point O during welding compared to before welding can also be obtained. These are the glass displacement deformations during welding, denoted as Δy and Δz.

2. The decoupling method for measuring deformation in glass-metal welding according to claim 1, characterized in that: In step S1, the main process of the pre-welding treatment is as follows: the glass is cleaned and dried, and the metal base is polished.

3. The decoupling method for measuring deformation in glass-metal welding according to claim 1, characterized in that: In step S2, the auxiliary film is an aluminum film or a copper film.

4. The decoupling method for measuring deformation in glass-metal welding according to claim 1, characterized in that: In step S4, the camera is a CCD camera.

5. The decoupling method for measuring deformation in glass-metal welding according to claim 1, characterized in that: In step S8, the specific process of the analysis and calculation is as follows: Step S81: Based on the spatial coordinate system constructed in step S5, analyze the position feature data to obtain the coordinate changes of point A on the y-axis and z-axis of the spatial coordinate system during the welding process, and the coordinate changes of point B on the y-axis and z-axis of the spatial coordinate system, respectively labeled as Y... A1 Z A1 and Y B1 Z B1 ; Step S82: Based on the initial position coordinates of points A and B in step S6, obtain the initial coordinate values ​​of point A on the y-axis and z-axis of the spatial coordinate system, and the initial coordinate values ​​of point B on the y-axis and z-axis of the spatial coordinate system, respectively. A0 Z A0 and Y B0 Z B0 ; Step S83: Analyze and calculate the changed coordinate values ​​and the initial coordinate values ​​to obtain the changes in the positional characteristics of point A along the y-axis and z-axis of the spatial coordinate system, and the changes in the positional characteristics of point B along the y-axis and z-axis of the spatial coordinate system, denoted as ΔY. A ΔZ A and ΔY B ΔZ B .

6. The decoupling method for measuring deformation in glass-metal welding according to claim 1, characterized in that: The specific calculation process for the deformation during glass-metal welding in step S10 is as follows: S101: Set the changes in the glass rotation around point O during the welding process and before welding as α, β, γ, and set the changes in the displacement of point O during the welding process and before welding as Δy, Δz. S102: During the welding process, the glass rotation observed by the autocollimator coupled with the translation of point O to form the displacement of the surface feature points observed by the camera. The total displacements of feature points A and B are respectively labeled as follows: The calculation formula is as follows: in, Let A be the displacement caused by rotating around point O. Let B be the displacement caused by rotating around point O. Let A be the displacement of point A as it translates with point O. Let B be the displacement of point B as it translates with point O. S103: Multiply each vector matrix successively to obtain the spatial rotation matrix [R]. XYZ ], spatial rotation matrix [R XYZ The calculation formula for ] is as follows: S103: Given the initial coordinates of points A and B, respectively A0(X) A0 Y A0 Z A0 ), B0(X B0 Y B0 Z B0 ), using the spatial rotation matrix [R XYZ Calculate the displacement of point A when it rotates around point O. The displacement caused by the rotation of point B around point O The calculation formula is as follows: Since the displacement of any point on the glass is the same as the translation of point O, we have: The changes in the glass's rotation around point O during the welding process compared to before welding, α, β, and γ, and the changes in the displacement of point O during the welding process compared to before welding, Δy and Δz, can be calculated using the following formulas: α = Δα; γ = Δγ; ΔyΔY A -[X A0 sinαcosβ+Y A0 (sinαsinβsinγ+cosαcosγ-1)+Z A0 (sinαsinβcosγ-cosαsinγ)] Δz=ΔZ A -[-X A0 sinβ+Y A0 cosβsinγ+Z A0 (cosβcosγ-1)]。

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