Laser dissimilar metal self-adaptive welding method and device based on blue light surrounding swing

Abstract

The invention provides a laser dissimilar metal self-adaption welding method and device based on blue light surrounding swing, and the method comprises the steps that welding material attributes and a laser welding technology needed in the composite laser welding process are obtained, and the welding material attributes and the laser welding technology are obtained based on laser welding power, a heat source acting position and the material attributes; the energy input quantity of red-blue composite laser absorbed by different metals in the welding process is calculated, the welding seam area of dissimilar metal materials in the welding process is obtained based on the characteristics of welding material attributes, the width of a composite laser welding pool is solved based on the laser welding swing amplitude, and the depth of the pool formed when a welded plate is infinite in thickness is calculated based on the width. And comparing the thickness with the actual thickness of the welded plate, determining the actual shape in the laser welding process, and predicting the appearance of the composite laser welding seam in combination with related shape parameters. The method solves the problems of poor welding joint forming quality, low mechanical property and the like caused by laser absorptivity difference of dissimilar metals and overlarge difference of thermophysical parameters.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of laser welding of dissimilar alloys, in particular to a laser dissimilar metal adaptive welding method and device based on blue light surrounding swing. BACKGROUND

[0002] With the rapid development of new manufacturing industry, the structure construction of single material has been difficult to meet the industrial development needs of new manufacturing industry. Dissimilar metal composite structure is concerned due to its low cost, lightweight and high performance. However, the thermal physical property difference between two dissimilar metals is too large, and the absorption rate of laser energy is also different, so it is difficult to achieve high-quality connection by using traditional welding method or trial-and-error method. Therefore, how to realize high-quality and high-strength connection of dissimilar materials has become one of the problems faced by the promotion of dissimilar metal composite materials.

[0003] In view of the above problems, CN 109570763 B authorized in 2019 records a dissimilar metal laser swing method and dissimilar metal welding equipment, which realizes the connection of dissimilar metals by swinging laser with a certain offset, but cannot accurately predict the welding quality of multiple materials. CN 113001024 B authorized in 2023 records a laser welding method of dissimilar materials, which realizes stable connection between dissimilar materials by using pre-prepared intermediate layer, but the pre-prepared intermediate layer will cause other elements to be added to the molten pool, which is not conducive to the application requirements in special environment. Therefore, it is necessary to design a laser dissimilar metal adaptive welding method and device based on blue light surrounding swing. SUMMARY

[0004] In order to overcome the shortcomings of the prior art, the purpose of the present application is to provide a laser dissimilar metal adaptive welding method and device based on blue light surrounding swing.

[0005] To achieve the above purpose, the present application provides the following scheme:

[0006] The present application provides a laser dissimilar metal adaptive welding method based on blue light surrounding swing, comprising:

[0007] Obtain the welding material properties and laser welding process required in the composite laser welding process, and read the related data from the database;

[0008] Based on the laser welding power, the heat source action position and the material properties, calculate the red-blue composite laser energy input W absorbed by different metals in the welding process;

[0009] Based on the characteristics of the welding material properties, the dissimilar metal material weld area S in the welding process is obtained; based on the laser welding swing amplitude A, the composite laser welding pool width B is solved, and based on this, the pool depth C formed when the welding plate is infinitely thick is calculated, which is compared with the actual welding plate thickness H to determine the actual shape in the laser welding process, combined with the relevant shape parameters, to predict the composite laser welding weld appearance;

[0010] Wherein, based on the laser welding power, heat source position and material properties, the red-blue composite laser energy input W absorbed by different metals in the welding process is calculated, specifically:

[0011] Based on the laser welding power, heat source position and material properties, the red-blue composite laser energy input W absorbed by different metals in the welding process is calculated, which is:

[0012] W=(1-η1)·(ε H1 ·W H1 +ε L1 ·W L1 )+(1-η2)·(ε H2 ·W H2 +ε L2 ·W L2 )

[0013] In the formula, W is the red-blue composite laser energy input absorbed by different metals in the welding process, that is, the total absorbed energy in the composite laser welding process, W H1 , W H2 is the total red light energy input to the two metals, W L1 , W L2 is the total blue light energy input to the two metals, ε H1 , ε H2 is the absorption rate of the first metal to red light and blue light, ε L1 , ε L2 is the absorption rate of the second metal to red light and blue light, η1 is the energy loss rate of the first metal, and η2 is the energy loss rate of the second metal.

[0014] Wherein, the total blue light energy input to the two metals W L1 , W L2 is:

[0015]

[0016] In the formula, W L is the total blue light energy, d is the offset distance to the first metal, and r is the light source action radius of the flat blue light;

[0017] Wherein, the total red light energy input to the two metals W H1 , WH2 is:

[0018]

[0019] wherein W H is the total energy of red light, t1 is the action time on the first metal, t2 is the action time on the second metal, t 总 is the total welding time.

[0020] Preferably, based on the characteristics of the welding material properties, the dissimilar metal material weld area S in the welding process is obtained, specifically:

[0021] Based on the characteristics of the welding material properties, the dissimilar metal material weld area S in the welding process is obtained, which is:

[0022] S = S1 + S2

[0023]

[0024] wherein S1 is the melting cross-sectional size of the first metal, S2 is the melting cross-sectional size of the second metal, C1 is the specific heat capacity of the first metal, C2 is the specific heat capacity of the second metal, T1 is the melting point of the first metal, T2 is the melting point of the second metal, k1 is the average temperature coefficient of the first metal molten pool, k2 is the average temperature coefficient of the second metal molten pool, ρ1 is the density of the first metal, ρ2 is the density of the second metal, and d is the length of the plate.

[0025] Preferably, the composite laser welding molten pool width B is solved based on the laser welding swing amplitude A, and based on this, the molten pool depth C formed when the welding plate is infinitely thick is calculated, specifically:

[0026] The composite laser welding molten pool width B is solved based on the laser welding swing amplitude A, and based on the composite laser welding molten pool width B, the melting depth on the first metal side, the melting depth on the second metal side, and the molten pool depth close to the second metal side are calculated, which are:

[0027] B = A + 2x

[0028]

[0029] wherein x is the difference between the swing welding track width and the actual weld width, which is approximately equal to 0 when the welding power is less than 1000W, is the melting depth on the first metal side, is the melting depth on the second metal side, and D is the molten pool depth close to the second metal side.

[0030] Preferably, the actual shape in the laser welding process is determined by comparing it with the actual welding plate thickness H, in combination with the relevant shape parameters, to predict the composite laser welding weld appearance, specifically:

[0031] If there is a value between D and exceeding 1.3 times the other value, the offset distance d is adjusted in advance;

[0032] After meeting the above conditions, if and are greater than the weld thickness H, the weld shape is predicted, and the specific prediction method is:

[0033] When and are 1-1.3 times the weld thickness H, the molten pool shape is cup-shaped;

[0034] When and exceed 1.3 times the weld thickness H, the molten pool will be broken through and cannot form a molten pool;

[0035] If is greater than the weld thickness H, the weld shape is predicted, and the specific prediction method is:

[0036] When is 1-1.3 times the weld thickness H, the molten pool shape is cup-shaped;

[0037] When exceeds 1.3 times the weld thickness H, the molten pool will be broken through and cannot form a molten pool;

[0038] If is greater than the weld thickness H, is less than the weld thickness H, the weld quality is poor in this case, and the offset distance d needs to be adjusted;

[0039] If and are less than the weld thickness H, the molten pool is in an arc shape, and the power is increased or maintained according to the actual welding requirements.

[0040] The application also provides a laser dissimilar metal self-adaptive welding device based on blue light surrounding swing, which comprises a blue light laser welding system, a fiber laser welding system and a welding monitoring system, the blue light laser welding system is used for outputting flat-top blue light to weld workpieces, the fiber laser welding system is used for outputting fiber laser to weld workpieces, and the welding monitoring system is used for acquiring weld appearance before welding and monitoring welding molten pool in real time, and adjusting swing track and welding parameters.

[0041] Preferably, the blue laser welding system comprises a blue laser generator, a blue lens and a reflecting mirror, the blue laser generator generates a blue light beam, the blue light beam passes through the blue lens and the reflecting mirror, and then is output to the workpiece through the unidirectional lens after being reflected.

[0042] Preferably, the fiber laser welding system comprises a fiber laser generator, a fiber lens and a remote galvanometer, the fiber laser generator generates a fiber light beam, the fiber light beam passes through the fiber lens, the remote galvanometer and the unidirectional lens, and is output to the workpiece.

[0043] Preferably, the welding monitoring system comprises an intelligent control device, a real-time monitoring device and a signal processor, the blue laser generator and the fiber laser generator are connected to the signal processor through a signal bus, the real-time monitoring device is arranged opposite to the workpiece, the real-time monitoring device is connected to the signal processor, and the signal processor is connected to the intelligent control device.

[0044] According to the specific embodiments of the present application, the following technical effects are disclosed.

[0045] The present application provides a laser dissimilar metal adaptive welding method and device based on blue light surrounding swing, the method comprises the following steps: obtaining the welding material properties and laser welding process required in the composite laser welding process, reading relevant data from the database, calculating the red-blue composite laser energy input W absorbed by different metals in the welding process based on the laser welding power, the heat source action position and the material properties, obtaining the dissimilar metal material weld area S in the welding process based on the characteristics of the welding material properties, solving the composite laser welding pool width B based on the laser welding swing amplitude A, calculating the pool depth C formed when the welding plate is infinitely thick, comparing the pool depth C with the actual welding plate thickness H, determining the actual shape in the laser welding process, combining the relevant shape parameters, and predicting the composite laser welding weld appearance, the system comprises a blue laser welding system, a fiber laser welding system and a welding monitoring system. The present application adopts the red-blue light composite swing welding mode to improve the absorption rate of dissimilar metal to laser energy, and solves the problems of poor weld joint forming quality and low mechanical properties caused by the large difference in laser absorption rate and thermal physical parameters of dissimilar metals by quickly predicting the shape of the dissimilar metal weld after welding. BRIEF DESCRIPTION OF DRAWINGS

[0046] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the drawings needed in the embodiments will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor.

[0047] Figure 1A blue light surrounding swing based laser dissimilar metal adaptive welding method flow chart provided by the embodiment of the present application is shown in the figure.

[0048] Figure 2 A blue light surrounding swing based laser dissimilar metal adaptive welding device structure diagram provided by the embodiment of the present application is shown in the figure.

[0049] The figure shows that: 1, blue light laser welding system; 10, blue light laser generator; 11, blue light lens; 12, blue light beam; 13, reflecting mirror; 2, fiber laser welding system; 20, fiber laser generator; 21, fiber lens; 22, remote galvanometer; 23, fiber beam; 24, one-way lens; 3, welding monitoring system; 30, intelligent control device; 31, real-time monitoring device; 32, signal bus; 33, signal processor; 4, workpiece. DETAILED DESCRIPTION

[0050] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.

[0051] The purpose of the present application is to provide a blue light surrounding swing based laser dissimilar metal adaptive welding method, which adopts a red-blue light composite swing welding mode to improve the absorption rate of dissimilar metals to laser energy, and solves the problems of poor weld joint forming quality and low mechanical properties caused by the large difference in laser absorption rate and thermal physical parameters of dissimilar metals through rapid prediction of the shape of the weld after welding dissimilar metals.

[0052] In order to make the above-mentioned purposes, features and advantages of the present application more obvious and easy to understand, the present application will be further described in detail below with reference to the drawings and specific embodiments.

[0053] Figure 1 The method flow chart provided by the embodiment of the present application is shown in the figure, and the present application provides a blue light surrounding swing based laser dissimilar metal adaptive welding method, which comprises: Figure 1

[0054] In step 100, the welding material properties and laser welding process required in the composite laser welding process are obtained, and the related data is read from the database;

[0055] In step 200, based on the laser welding power, the heat source action position and the material properties, the red-blue composite laser energy input amount W absorbed by different metals in the welding process is calculated;

[0056] ​In step 300, based on the characteristics of the welding material properties, the dissimilar metal material weld area S in the welding process is obtained;

[0057] In step 400, the composite laser welding molten pool width B is solved based on the laser welding swing amplitude A, and the molten pool depth C formed when the welding plate is infinitely thick is calculated based on this, which is compared with the actual welding plate thickness H to determine the actual shape in the laser welding process, and the relevant shape parameters are combined to predict the composite laser welding weld appearance.

[0058] The workpiece can be aluminum, magnesium, copper and other dissimilar difficult-to-weld metals, and the plate thickness is 1-4mm, which is made of two metals, namely No. 1 metal and No. 2 metal.

[0059] In step 200, based on the laser welding power, heat source action position and material properties, the red-blue composite laser energy input W absorbed by different metals in the welding process is calculated, specifically:

[0060] Based on the laser welding power, heat source action position and material properties, the red-blue composite laser energy input W absorbed by different metals in the welding process is calculated, which is:

[0061] W=(1-η1)·(ε H1 ·W H1 +ε L1 ·W L1 )+(1-η2)·(ε H2 ·W H2 +ε L2 ·W L2 )

[0062] In the formula, W is the red-blue composite laser energy input absorbed by different metals in the welding process, that is, the total absorbed energy in the composite laser welding process, W H1 , W H2 is the total red light energy input to the two metals, W L1 , W L2 is the total blue light energy input to the two metals, ε H1 , ε H2 is the absorption rate of No. 1 metal to red light and blue light, ε L1 , ε L2 is the absorption rate of No. 2 metal to red light and blue light, η1 is the energy loss rate of No. 1 metal, and η2 is the energy loss rate of No. 2 metal;

[0063] The present application provides two methods for calculating the total blue light and red light energy, the first of which takes blue light as an example, and the total blue light energy input to the two metals W L1 , W L2 is:

[0064]

[0065] In the formula, W L is the total energy of blue light, d is the offset distance to the first metal, and r is the source action radius of the flat-top blue light;

[0066] In the second example with red light, the total energy of red light input to the two metals is W H1 , W H2 :

[0067]

[0068] In the formula, W H is the total energy of blue light, t1 is the action time on the first metal, t2 is the action time on the second metal, and t 总 is the total welding time;

[0069] The two methods can be interchanged, and the specific requirements can be selected.

[0070] In step 300, based on the characteristics of the welding material properties, the heterogeneous metal material weld area S in the welding process is obtained, specifically:

[0071] Based on the characteristics of the welding material properties, the heterogeneous metal material weld area S in the welding process is obtained, which is:

[0072] S = S1 + S2

[0073]

[0074] In the formula, S1 is the melting cross-sectional size of the first metal, S2 is the melting cross-sectional size of the second metal, C1 is the specific heat capacity of the first metal, C2 is the specific heat capacity of the second metal, T1 is the melting point of the first metal, T2 is the melting point of the second metal, k1 is the average temperature coefficient of the first metal molten pool, k2 is the average temperature coefficient of the second metal molten pool, ρ1 is the density of the first metal, ρ2 is the density of the second metal, and d is the length of the plate.

[0075] In step 400, the composite laser welding molten pool width B is solved based on the laser welding swing amplitude A, and the molten pool depth C formed when the welding plate is infinitely thick is calculated based on this, specifically:

[0076] The composite laser welding molten pool width B is solved based on the laser welding swing amplitude A, and the melting depth on the first metal side, the melting depth on the second metal side, and the molten pool depth close to the second metal side are calculated based on the composite laser welding molten pool width B, which are:

[0077] B = A + 2x

[0078]

[0079] In the formula, x is the difference between the swing welding track width and the actual welding width, which is about equal to 0 when the welding power is less than 1000W, D1 is the melting depth of the first metal side, D2 is the melting depth of the second metal side, and D is the depth of the molten pool close to the second metal side.

[0080] In step 400, the actual shape in the laser welding process is determined by comparing it with the actual welding plate thickness H, and the composite laser welding weld shape is predicted in combination with the relevant shape parameters, specifically as follows:

[0081] If there is a value between D and D that exceeds 1.3 times the other value, the offset distance d is adjusted in advance; After meeting the above conditions, if D and D are greater than the weld thickness H, the weld shape is predicted, and the specific prediction method is as follows:

[0082] When D and D are 1-1.3 times the weld thickness H, the molten pool shape is a wine cup shape;

[0083] When D and D exceed 1.3 times the weld thickness H, the molten pool will be broken through and cannot form a molten pool; If D is greater than the weld thickness H,

[0084] When D is 1-1.3 times the weld thickness H, the molten pool shape is a wine cup shape; When D exceeds 1.3 times the weld thickness H, the molten pool will be broken through and cannot form a molten pool;

[0085] If D is greater than the weld thickness H, When D is 1-1.3 times the weld thickness H, the molten pool shape is a wine cup shape;

[0086] When D exceeds 1.3 times the weld thickness H, the molten pool will be broken through and cannot form a molten pool;

[0087] If D is greater than the weld thickness H, If D and D are both less than the weld thickness H, the molten pool is in an arc shape, and the power is increased or maintained according to the actual welding requirements.

[0088] If D and D are both less than the weld thickness H, The weld quality is poor in this case, and the offset distance d needs to be adjusted.

[0089] If D and D are both less than the weld thickness H, the molten pool is in an arc shape, and the power is increased or maintained according to the actual welding requirements. If D and D are both less than the weld thickness H,

[0090] Figure 2 ​​​​​​​​As shown, the application also provides a laser hetero-metal adaptive welding device based on blue light surrounding swing, comprising: a blue light laser welding system 1, a fiber laser welding system 2 and a welding monitoring system 3, the blue light laser welding system 2 is used for outputting flat top blue light, and the workpiece 4 is welded, the fiber laser welding system 3 is used for outputting fiber laser, and the workpiece 4 is welded, and the welding monitoring system 3 is used for obtaining weld appearance before welding and real-time monitoring of welding pool, and adjusting swing track and welding parameters.

[0091] The blue light laser welding system 1 comprises a blue light laser generator 10, a blue light lens 11 and a reflecting mirror 13, the blue light laser generator 10 generates a blue light beam 12, which is output to the workpiece through the blue light lens 11 to the reflecting mirror 13, and then output to the workpiece through the one-way lens 24 after reflection.

[0092] The fiber laser welding system 2 comprises a fiber laser generator 20, a fiber lens 21 and a remote galvanometer 22, the fiber laser generator 20 generates a fiber light beam 23, which is output to the workpiece 4 through the fiber lens 21, the remote galvanometer 22 and the one-way lens 24.

[0093] The welding monitoring system 3 comprises an intelligent control device 30, a real-time monitoring device 31 and a signal processor 32, the blue light laser generator 10 and the fiber laser generator 20 are connected to the signal processor 33 through a signal bus 32, the real-time monitoring device 31 is arranged opposite to the workpiece 4, the real-time monitoring device 31 is connected to the signal processor 32, and the signal processor 32 is connected to the intelligent control device 30.

[0094] The embodiments in the specification are described in a progressive manner, and each embodiment focuses on the difference from other embodiments, and the same or similar parts between the embodiments can be referred to each other.

[0095] The principles and implementation modes of the application are described by applying specific examples in this paper, and the above embodiment description is only used to help understand the method and core idea of the application; at the same time, for the general technical personnel in the art, according to the idea of the application, the specific implementation mode and application range will be changed. In view of the above, the content of the specification should not be understood as the limitation of the application.

Claims

1. A laser-based adaptive welding method for dissimilar metals based on blue light oscillation, characterized in that, include: Obtain the welding material properties and laser welding process required for the composite laser welding process, and read relevant data from the database; Based on laser welding power, heat source location, and material properties, the amount of red-blue composite laser energy input W absorbed by different metals during the welding process is calculated. Based on the characteristics of the welding material properties, the weld area S of dissimilar metal materials is obtained during the welding process; the width B of the composite laser welding molten pool is solved based on the laser welding oscillation amplitude A; based on this, the depth C of the molten pool formed when the welding plate is infinitely thick is calculated; it is compared with the actual welding plate thickness H to determine the actual shape during the laser welding process; and combined with relevant shape parameters, the morphology of the composite laser welding weld is predicted. Specifically, based on the laser welding power, the location of the heat source, and the material properties, the red-blue composite laser energy input W absorbed by different metals during the welding process is calculated as follows: Based on the laser welding power, the location of the heat source, and the material properties, the red-blue composite laser energy input W absorbed by different metals during the welding process is calculated as follows: W=(1-η1)·(ε H1 ·W H1 +e L1 ·W L1 )+(1-η2)·(ε H2 ·W H2 +e L2 ·W L2 ) In the formula, W represents the amount of red-blue composite laser energy input absorbed by different metals during the welding process, i.e., the total energy absorbed during composite laser welding. H1 W H2 W is the sum of the red light energy input to the two metals. L1 W L2 ε is the sum of the blue light energy input to the two metals. H1 ε H2 ε represents the absorption rate of red and blue light by metal number one. L1 ε L2 η1 represents the absorption rate of red and blue light by metal II, η2 represents the energy loss rate of metal I, and η2 represents the energy loss rate of metal II. Among them, the total blue light energy input to the two metals is W L1 W L2 for: In the formula, W L denoted as the total energy of the blue light, d as the offset distance towards metal number one, and r as the effective radius of the flat-top blue light source. Among them, the total red light energy input to the two metals, W H1 W H2 for: In the formula, W H Let t be the total energy of the red light, t1 be the time of interaction on metal 1, t2 be the time of interaction on metal 2, and t... 总 This represents the total welding time.

2. The method according to claim 1, characterized in that, Based on the characteristics of welding material properties, the weld area S of dissimilar metal materials during the welding process is obtained, specifically: Based on the characteristics of the welding material properties, the weld area S of dissimilar metal materials during the welding process is obtained as follows: S = S1 + S2 In the formula, S1 is the melting cross-sectional dimension of metal 1, S2 is the melting cross-sectional dimension of metal 2, C1 is the specific heat capacity of metal 1, C2 is the specific heat capacity of metal 2, T1 is the melting point of metal 1, T2 is the melting point of metal 2, k1 is the average temperature coefficient of the molten pool of metal 1, k2 is the average temperature coefficient of the molten pool of metal 2, ρ1 is the density of metal 1, ρ2 is the density of metal 2, and d is the length of the plate.

3. The method according to claim 2, characterized in that, The width B of the composite laser welding molten pool is calculated based on the laser welding oscillation amplitude A. Based on this, the depth C of the molten pool formed when the welding plate is infinitely thick is calculated, specifically: The width of the molten pool in the composite laser welding is calculated based on the laser welding oscillation amplitude A. Then, the melting depth on the first metal side, the melting depth on the second metal side, and the molten pool depth near the second metal side are calculated based on the width of the molten pool B. B = A + 2·x In the formula, x is the difference between the width of the oscillating welding trajectory and the actual weld width. When the welding power is below 1000W, this value is approximately equal to 0. The melting depth of the first metal side. denoted as the melting depth on the second metal side, and D as the molten pool depth near the second metal side.

4. The method according to claim 3, characterized in that, The process involves comparing the actual shape of the welded plate with the thickness H of the welded plate to determine the actual shape during laser welding. Combined with relevant shape parameters, the morphology of the composite laser weld is predicted. Specifically: If D and If one value exceeds 1.3 times another value, then the offset distance d should be adjusted in advance; After the above conditions are met, if and If all values ​​are greater than the weld thickness H, then the weld shape is predicted. The specific prediction method is as follows: when and If the weld thickness H is 1-1.3 times, the resulting molten pool will be goblet-shaped. when and If the weld thickness exceeds 1.3 times the weld thickness H, the molten pool will be broken through and a molten pool cannot be formed; like If the weld thickness is greater than H, then the weld shape is predicted. The specific prediction method is as follows: when If the weld thickness H is 1-1.3 times, the resulting molten pool will be goblet-shaped. when If the weld thickness exceeds 1.3 times the weld thickness H, the molten pool will be broken through and a molten pool cannot be formed; like Greater than the weld thickness H, If the offset distance is less than the weld thickness H, the weld quality is poor and the offset distance d needs to be adjusted. like and If all values ​​are less than the weld thickness H, the molten pool will be arc-shaped. Depending on the actual welding requirements, you can choose to increase the power or maintain the status quo.

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