Closed-loop laser welding assembly

Abstract

Systems, methods, and assemblies for forming or employing closed loop laser welds are described. The closed-loop laser welding may be formed by, for example, actuating a laser on a substrate at a first point to initiate the welding and scanning the laser along a start welding path, along a main welding path, and along an end welding path. The starting weld path is from a first point to a second point. The main weld path is from a second point to a third point. The end weld path is from a third point to a fourth point. The laser is scanned from the second spot to the third spot such that the weld bead of the main weld path defines an inner perimeter and an outer perimeter. The outer periphery defines a closed-loop laser weld. The first point and the fourth point are within the inner perimeter.

Description

Technical Field

[0001] The present disclosure relates to the field of welding, and more particularly, to systems and methods for laser welding lap joints. Background Art

[0002] Laser lap welding is used in the automotive industry to join parts. Laser weld shapes include line welds (e.g., a linear path), "C" welds (e.g., an arcuate path forming a section of a circle), and staple welds (e.g., a linear path with a section of a circle at both ends). Although staple welds are widely used, high stress concentrations may compromise the strength of the weld. Therefore, there is a need in the art to reduce the stress concentrations generated during laser welding. Summary of the invention

[0003] Systems, methods, and apparatus according to the present disclosure provide laser welding that uses a closed loop to optimize stress concentration. In some aspects, the closed-loop laser welding optimizes stress concentration using symmetrical loading conditions. In some additional or alternative aspects, the closed-loop laser welding optimizes stress concentration by placing the start and end points of the laser weld within a perimeter formed by a weld bead of the closed-loop laser weld. In some examples, the maximum principal stress of the closed-loop laser lap weld is reduced by 20% compared to a similar non-closed-loop laser lap weld.

[0004] Advantageously, the closed-loop laser welding according to the present disclosure can optimize the reliability and durability of laser lap joints. In addition, the closed-loop laser welding can reduce the welding steps required to bond substrates, the energy required to meet the performance indicators of the welded joints, the component density of the welded parts, and combinations thereof.

[0005] According to various aspects of the present disclosure, a method includes actuating a laser on a substrate at a first point to initiate welding and scanning the laser along a starting welding path, along a main welding path, and along an ending welding path. The starting welding path is from the first point to the second point. The main welding path is from the second point to the third point. The ending welding path is from the third point to the fourth point. The laser is scanned from the second point to the third point so that the weld bead of the main welding path defines an inner perimeter and an outer perimeter. The outer perimeter defines a closed-loop laser weld. The first point and the fourth point are within the inner perimeter.

[0006] According to a further aspect of the present disclosure, the closed-loop laser welding comprises a first rounded portion and a second rounded portion opposite to each other, and a first elongated portion and a second elongated portion opposite to each other. The first elongated portion connects a first end of the first rounded portion to a first end of the second rounded portion, and the second elongated portion connects a second end of the first rounded portion to a second end of the second rounded portion.

[0007] According to a further aspect of the present disclosure, the first elongated portion defines a length between a first end of the first rounded portion and a first end of the second rounded portion. The first rounded portion defines a first radius, and a ratio of the length between the rounded portions to the first radius is between 2 and 10.

[0008] According to a further aspect of the present disclosure, the first elongated portion defines a length between a first end of the first rounded portion and a first end of the second rounded portion, and the first rounded portion defines a first radius. A ratio of the length to the first radius is between 2.5 and 4.

[0009] According to a further aspect of the present disclosure, the first elongated portion defines a length between a first end of the first rounded portion and a first end of the second rounded portion, and the first rounded portion defines a first radius, and a ratio of the length to the first radius is between 2.5 and 3.2.

[0010] According to a further aspect of the present disclosure, the second point and the third point are located on the first elongated portion.

[0011] According to a further aspect of the present disclosure, the second point and the third point are located on the second elongated portion.

[0012] According to a further aspect of the present disclosure, the operating parameters of the laser include a first set of operating parameters for a starting welding path, a second set of operating parameters for a main welding path, and a third set of operating parameters for an ending welding path. The first set of operating parameters includes a ramp-up from a first laser power to a second laser power. The second set of operating parameters includes a second laser power. The third set of operating parameters includes a ramp-down from the second laser power to a third laser power.

[0013] According to further aspects of the present disclosure, the third laser power is lower than the first laser power.

[0014] According to various aspects of the present disclosure, a closed-loop laser weld includes a first rounded portion and a second rounded portion opposite to each other, a first elongated portion and a second elongated portion opposite to each other, and a first terminal portion and a second terminal portion. The first elongated portion connects a first end of the first rounded portion to a first end of the second rounded portion, and the second elongated portion connects a second end of the first rounded portion to a second end of the second rounded portion. The closed-loop laser weld is formed by scanning a laser on a substrate sequentially through the first terminal portion, a first portion of the first elongated portion, a first rounded portion, a second elongated portion, a second rounded portion, a second portion of the first elongated portion, and a second terminal portion.

[0015] According to a further aspect of the present disclosure, the first elongated portion defines a length between a first end of the first rounded portion and a first end of the second rounded portion, and the first rounded portion defines a first radius. A ratio of the length to the first radius is between 2 and 10.

[0016] According to a further aspect of the present disclosure, the first elongated portion defines a length between a first end of the first rounded portion and a first end of the second rounded portion, and the first rounded portion defines a first radius. A ratio of the length to the first radius is between 2.5 and 4.

[0017] According to a further aspect of the present disclosure, the first elongated portion defines a length between a first end of the first rounded portion and a first end of the second rounded portion, and the first rounded portion defines a first radius, and a ratio of the length to the first radius is between 2.5 and 3.2.

[0018] According to a further aspect of the present disclosure, the first terminal portion, the first portion of the first elongated portion, the second portion of the first elongated portion, and the second terminal portion meet at an intersection.

[0019] According to a further aspect of the present disclosure, scanning the laser over the substrate includes a first set of operating parameters for the first terminal portion, a second set of operating parameters for the first portion of the first elongated portion, the first rounded portion, the second elongated portion, the second rounded portion, and the second portion of the first elongated portion, and a third set of operating parameters for the second terminal portion. The first set of operating parameters includes a ramp-up from a first laser power to a second laser power. The second set of operating parameters includes the second laser power. The third set of operating parameters includes a ramp-down from the second laser power to a third laser power.

[0020] According to further aspects of the present disclosure, the third laser power is lower than the first laser power.

[0021] According to various aspects of the present disclosure, an assembly includes a first substrate, a second substrate, and a closed-loop laser weld that bonds the first substrate to the second substrate. The closed-loop laser weld includes a first rounded portion and a second rounded portion that are opposite to each other, a first elongated portion and a second elongated portion that are opposite to each other, and a first terminal portion and a second terminal portion. The first elongated portion connects the first end of the first rounded portion to the first end of the second rounded portion, and the second elongated portion connects the second end of the first rounded portion to the second end of the second rounded portion, thereby forming a perimeter. The first terminal portion and the second terminal portion are located within the perimeter. The closed-loop laser weld is formed by scanning a laser on the substrate through the first terminal portion, the first portion of the first elongated portion, the first rounded portion, the second elongated portion, the second rounded portion, the second portion of the first elongated portion, and the second terminal portion in sequence.

[0022] According to a further aspect of the present disclosure, in the assembly, the first elongated portion defines a length between a first end of the first rounded portion and a first end of the second rounded portion, and the first rounded portion defines a first radius, and a ratio of the length to the first radius is between 2.5 and 3.2.

[0023] According to a further aspect of the present disclosure, in the assembly, the first terminal portion, the first portion of the first elongated portion, the second portion of the first elongated portion, and the second terminal portion meet at an intersection.

[0024] According to a further aspect of the present disclosure, in the assembly, scanning the laser over the substrate includes a first set of operating parameters for the first terminal portion, a second set of operating parameters for the first portion of the first elongated portion, the first rounded portion, the second elongated portion, the second rounded portion, and the second portion of the first elongated portion, and a third set of operating parameters for the second terminal portion. The first set of operating parameters includes a ramp-up from a first laser power to a second laser power. The second set of operating parameters includes the second laser power. The third set of operating parameters includes a ramp-down from the second laser power to a third laser power.

[0025] The above features and advantages and other features and advantages of the present disclosure are readily apparent from the following detailed description of the best modes for carrying out the disclosure when taken in connection with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] The drawings are illustrative and are not intended to limit the subject matter defined by the claims. Exemplary aspects are discussed in the following detailed description and are shown in the accompanying drawings, in which:

[0027] Figure 1 shows an illustrative closed-loop laser welding according to various aspects of the present disclosure;

[0028] Figure 2 shows a second illustrative closed-loop laser welding according to various aspects of the present disclosure;

[0029] Figure 3 An example welding path for forming a closed loop laser weld according to various aspects of the present disclosure is shown;

[0030] Figure 4 An assembly employing exemplary closed-loop laser welding according to various aspects of the present disclosure is shown;

[0031] Figure 5 Shows Figure 4 A graph of simulation results of the maximum stress of an example weld in an assembly of;

[0032] Figure 6 Shows Figure 4 Part of the finite element analysis results on the principal stresses in the open-loop laser welding of the component;

[0033] Figure 7 It is shown that according to various aspects of the present disclosure, Figure 4Part of the finite element analysis results of the principal stresses on the first closed-loop laser weld of the component;

[0034] Figure 8 It is shown that according to various aspects of the present disclosure, Figure 4 Finite element analysis results of the second closed-loop laser welding principal stress in the component;

[0035] Fig. 9 It is shown that according to various aspects of the present disclosure, Figure 4 Finite element analysis results of the third closed-loop laser welding principal stress in the component; and

[0036] Fig.10 It is shown that according to various aspects of the present disclosure, Figure 4 An example method of forming a closed-loop laser weld in an assembly. DETAILED DESCRIPTION

[0037] The following detailed description is merely exemplary in nature and is not intended to limit the application and use. In addition, there is no intention to be bound by any expressed or implied theory presented in the foregoing technical field, background technology, summary of the invention or the following detailed description.

[0038] Figure 1 An illustrative closed loop laser weld 100 is shown. The closed loop laser weld 100 includes a weld bead 102 defining a radiused portion 104, an elongated portion 106, and a terminal portion 108, wherein the terminal portion 108 and one of the elongated portions 106 meet at an intersection 110. The weld bead 102 also defines an outer perimeter 112 and an inner perimeter 114. The radiused portion 104 has a radius of curvature R. The elongated portion 106 extends a length L between the radiused portions 104. The closed loop laser weld 100 shown has a ratio of length L to radius R of 4:1 (or simply 4).

[0039] The terminal portions 108 are disposed within the inner perimeter 114 of the closed-loop laser weld 100. Each terminal portion 108 is the start or end point of a weld path. While not being bound by theory, it is believed that disposing the terminal portions 108 within the inner perimeter 114 of the closed-loop laser weld 100 can optimize the strength of the closed-loop laser weld 100 by enhancing uniformity and performance control of portions of the weld bead 102 that are exposed to or experience stress concentrations. For example, the closed-loop laser weld 100 reduces the impact of weld defects associated with weld initiation and termination and asymmetric loading conditions on the weld bead 102.

[0040] Figure 2A second illustrative closed-loop laser weld 200 is shown. The closed-loop laser weld 200 includes a weld bead 202 defining a radiused portion 204, an elongated portion 206, and a terminal portion 208, wherein the terminal portion 208 and one of the elongated portions 206 meet at an intersection 210. The weld bead 202 also defines an outer perimeter 212 and an inner perimeter 214. The radiused portion 204 has a radius of curvature R. The elongated portion 206 has a length L extending between the radiused portions. The closed-loop laser weld 100 shown has a ratio of length L to radius R of 2.5:1 (or simply 2.5).

[0041] The terminal portions 208 are disposed within the inner perimeter 214 of the closed-loop laser weld 200. Each terminal portion 208 is a starting point or an end point of a welding path. Figure 1 Compared to the closed-loop laser weld 100 of FIG. 1 , the ratio of the length L to the radius R of the second closed-loop laser weld 200 has been reduced, and the size of the second terminal portion 208 can remain the same as the first terminal portion 108. In some aspects, the size and / or shape of the terminal portion is determined based on the width of the weld beads 102, 202.

[0042] Figure 3 An example welding path 300 for forming a closed loop laser weld is shown. The welding path 300 includes a starting welding path 302a, a main welding path 302b, and an ending welding path 302c (collectively referred to as "welding paths 302"). The starting welding path 302a follows a first terminal portion 308a and the ending welding path 302c follows a second terminal portion 308b.

[0043] The main welding path 302b forms a first rounded portion 304a and a second rounded portion 304b opposite to each other, and a first elongated portion 306a and a second elongated portion 306b opposite to each other. The first elongated portion 306a connects a first end 322a of the first rounded portion 304a to a first end 324a of the second rounded portion 304b, and the second elongated portion 306a connects a second end 322b of the first rounded portion 304a to a second end 324b of the second rounded portion 304b.

[0044] The main welding path is formed by scanning the laser on the substrate through the first terminal portion 308a, the first portion 309a of the first extension portion 306a, the first chamfered portion 304a, the second extension portion 306b, the second chamfered portion 304b, the second portion 309b of the first extension portion 306a and the second terminal portion 308b in sequence.

[0045] The laser on the substrate is actuated at the first point 310 to initiate welding, and the laser is scanned along the starting welding path 302a from the first point 310 to the second point 312 to form the first terminal portion 308a. Then, the laser is scanned along the main welding path 302b from the second point 312 to the third point 314, so that the weld bead of the main welding path forms a closed-loop laser weld. After the closed-loop laser weld is formed, the laser is scanned along the ending welding path 302c from the third point 314 to the fourth point 316 to form the second terminal portion 308b. The weld bead of the main welding path 302b defines an outer perimeter 318 and an inner perimeter 320. The first point 310 and the fourth point 316 are within the inner perimeter 320.

[0046] Each of the first rounded portion 304a and the second rounded portion 304b defines a radius R. Each of the first elongated portion 306a and the second elongated portion 306b defines a length L between the first rounded portion 304a and the second rounded portion 304b. In some aspects, the ratio of the length L to the radius R is between 2 and 10. In other aspects, the ratio of the length L to the radius R is between 2.5 and 4. In yet further aspects, the ratio of the length L to the radius R is between 2.5 and 3.2. Advantageously, as will be described with reference to Figure 5 As discussed, the ratio may be selected based on the expected maximum principal stress experienced by the weld.

[0047] In the illustrated example, the second point 312 and the third point 314 are co-located such that the starting weld path 302a, the main weld path 302b, and the ending weld path 302c have a common intersection point (eg, Figure 1 In some aspects, the third point 314 is located before the second point 312, and the operating parameters of the laser are selected to provide sufficient temperature and fluid flow to close the loop. In some aspects, the third point 314 is located after the second point 312, and the laser parameters used between the second point 312 and the third point 314 of each pass are selected to provide uniform material properties along the weld bead of the main weld 302b for the single pass portion and the overlap portion.

[0048] The operating parameters of the laser may be continuous or may be varied between one or more segments of the welding path 302 to achieve desired properties of the resulting weld bead 102. These parameters may include, for example, scan speed, scan pattern, laser power, laser power ramp profile, laser pulse characteristics, combinations thereof, and the like.

[0049] If the parameters remain constant, the material properties of the weld bead 102 may differ between the starting point (e.g., first point 310) of the starting weld path 302a, the ending point (e.g., fourth point 316) of the main weld path 302b, and the ending weld path 302c. For example, the base plate temperature, heating profile, and environment used to form the weld at the starting point will be different from those conditions used to form the weld along the main weld path 302 and the ending weld path 302c. In addition, the cooling profile and environment used to form the weld at the ending point will be different from the cooling profile and environment used to form the weld along the starting weld path 302a and the main weld path 302b. Advantageously, as described herein, disposing the terminal portion 308 within the inner perimeter 320 enhances the resulting weld by reducing the non-uniformity of the weld bead 102 exposed to external stresses.

[0050] Additionally, positioning the terminal portions 308a, 308b within the inner perimeter 320 optimizes control of the material properties of the weld bead 102 to supplement or provide uniformity along the main weld path 302b of the weld bead 102. For example, positioning the terminal portion 108 within the inner perimeter of the closed-loop laser weld 100 reduces the stress concentration experienced by the weld bead 102 resulting from the coupling of operating parameters used at the start and end points of the weld.

[0051] In some aspects, the laser is operated at a first set of operating parameters for the starting weld path 302a, a second set of operating parameters for the main weld path 302b, and a third set of operating parameters for the ending weld path 302c. For example, the laser parameters for the starting weld path 302a can be selected to ramp up from a first lower power setting to a second higher power setting before the laser reaches the intersection 110 (e.g., the second point 312) with the main weld path 302b. The laser can then be operated at the second higher power setting through the main weld path 302b until it reaches the intersection 110a a second time (e.g., the third point 314), where it continues to the ending weld path 302c. The laser parameters for the ending weld path 302c can ramp down from the second higher power setting to a third lower power setting to end the weld path 302. In some aspects, the third power setting is higher than the first power setting. In further aspects, the third power setting is lower than the first power setting.

[0052] Additionally or alternatively, design features of the terminal portion 308 may be selected to enhance the uniformity of stress distribution of the portion of the weld bead 102 corresponding to the main path 302b. For example, the starting point (e.g., the first point 310) and / or the shape of the starting path 302a may be selected to reduce differential conditions between the intersection point 110 and the remainder of the main path 302b at the beginning of the weld bead 102. Similarly, the ending point (e.g., the fourth point) and / or the shape of the ending path 302c may be selected to reduce differential conditions between the main path 302b and the intersection point 110 at the end of the weld bead 102. While not being bound by theory, it is believed that the symmetrical terminal portion 306 may further optimize stress performance on the weld bead 102.

[0053] Figure 4 An assembly 400 is shown that employs an example closed-loop laser weld 100. The closed-loop laser weld 100 bonds a first substrate 402 to a second substrate 404 to form the assembly 400. The substrates 402, 404 may be, for example, sheets of metal.

[0054] Figure 5 The maximum stress σ expressed as the ratio of length L to radius R for an example weld in assembly 400 is shown. max The graph includes a graph showing the maximum stress σ of closed-loop laser welding. max The trend line 502 is shown in Figure 5. It can be seen that the maximum stress σ of closed-loop laser welding max The increase is faster when the ratio is 2.5-4 than when the ratio is 4-10. Although not being bound by theory, it is believed that as the ratio of length L to radius R approaches zero (e.g., a circle), decreasing the ratio of length L to radius R can gradually optimize the stress on the weld.

[0055] The graph also includes point 504, which shows the maximum stress σ of the staple weld. max It can be seen that the maximum stress σ of the staple welding with a length L to radius R ratio of 10 is max The maximum stress σ of closed-loop laser welding with the same ratio of length L to radius R is about 192 MPa. max It is about 155Mpa, which is reduced by about 20%.

[0056] Figure 6 FIG. 6 is a portion of a finite element analysis result 600 of the principal stresses on an open-loop laser weld 602 having a staple configuration and a length L to radius R ratio of 10:1. Figure 4 As shown. The first sheet and the second sheet are each 150 mm long and 50 mm wide. The first substrate and the second substrate overlap by 40 mm. The open loop laser weld 602 is located at the center of the overlap area, with a length L of 25 mm and a radius R of 2.5 mm.

[0057] Maximum principal stress σ of 602 in open-loop laser welding max The maximum principal stress σ of open-loop laser welding 602 is 191.7Mpa. max The radiused portion of the staple, which is distributed about 180° from the elongated portion at point 604, is located halfway through the weld thickness. The principal stress σ decreases uniformly from a maximum at the center of the thickness to a minimum at each surface 606.

[0058] The interior of the elongated portion of the open loop laser weld 602 is subject to a principal stress of approximately 72.3 MPa extending between a point 608 at the end of the elongated portion and a point 610 at the center of the elongated portion.

[0059] Figure 7 FIG. 7 is a portion of a finite element analysis result 700 showing the principal stresses on a closed loop laser weld 702 with a length L to radius R ratio of 10:1. Figure 4 As shown. The first sheet and the second sheet are each 150 mm long and 50 mm wide. The first substrate and the second substrate overlap by 40 mm. The closed loop laser weld 702 is located at the center of the overlap area. The length L of the closed loop laser weld 702 is 25 mm and the radius R is 2.5 mm.

[0060] Maximum principal stress σ of 702 in closed-loop laser welding max The maximum principal stress σ of closed-loop laser welding 702 is 154.6Mpa. max Located on the side of the closed loop laser weld 702 with the terminal portion 308, in the middle of the weld thickness at the transition 704 from the elongated portion to the radiused portion. The principal stress σ decreases uniformly from a maximum at the center of the thickness to a minimum at each surface 706.

[0061] Point 708 near intersection 110 experiences a principal stress of approximately 119.4 MPa. The interior of the elongated portion opposite terminal portion 308 experiences a principal stress of approximately 57.8 MPa extending between point 710 at the end of the elongated portion and point 712 at the center of the elongated portion.

[0062] Figure 8 The finite element analysis results 800 of the principal stress on the closed loop laser weld 802 with a length L to radius R ratio of 4:1 are shown. The peel test model of the closed loop laser weld 802 is shown in FIG. Figure 4 As shown. The first sheet and the second sheet are each 150 mm long and 50 mm wide. The first substrate and the second substrate overlap by 40 mm. The closed-loop laser weld 802 is located at the center of the overlap region. The length L of the closed-loop laser weld 802 is 10 mm and the radius R is 2.5 mm.

[0063] Maximum principal stress σ of 802 in closed-loop laser weldingmax The maximum principal stress σ of closed-loop laser welding 802 is 149.5Mpa. max Located on the side of the closed loop laser weld 802 having the terminal portion 308, in the middle of the weld thickness at the transition 804 from the elongated portion to the radiused portion. The principal stress σ decreases uniformly from a maximum at the center of the thickness to a minimum at each surface 806.

[0064] Point 808 near intersection 110 experiences a principal stress of approximately 115.5 MPa. The interior of the elongated portion opposite terminal portion 308 experiences a principal stress of approximately 55.9 MPa extending between point 810 at the end of the elongated portion and point 812 at the center of the elongated portion.

[0065] Fig. 9 The finite element analysis results 900 of the principal stresses on a closed loop laser weld 902 with a length L to radius R ratio of 2.5:1 are shown. The model of the peel test of the closed loop laser weld 902 is as follows Figure 4 As shown. The first sheet and the second sheet are each 150 mm long and 50 mm wide. The first substrate and the second substrate overlap by 40 mm. The closed loop laser weld 902 is located at the center of the overlap area. The length L of the closed loop laser weld 902 is 6.25 mm and the radius R is 2.5 mm.

[0066] Maximum principal stress σ of 902 in closed-loop laser welding max The maximum principal stress σ of closed-loop laser welding 902 is 132.0Mpa. max Located on the side of the closed loop laser weld 902 having the terminal portion 308, in the middle of the weld thickness at the transition 904 from the elongated portion to the radiused portion. The principal stress σ decreases uniformly from a maximum at the center of the thickness to a minimum at each surface 906.

[0067] Point 908 near intersection 110 experiences a principal stress of approximately 101.9 MPa. The interior of the elongated portion opposite terminal portion 308 experiences a principal stress of approximately 49.2 MPa extending between point 910 at the end of the elongated portion and point 912 at the center of the elongated portion.

[0068] Fig.10An example method 1000 for forming a closed-loop laser weld is shown. The method 1000 begins at box 1002, where a laser on a substrate is actuated at a first point to initiate welding. The substrate may be, for example, the first substrate 402 or the second substrate 404. At box 1004, the laser is scanned along a starting weld path from the first point to the second point. At box 1006, the laser is scanned along a main weld path from the second point to a third point, such that the weld bead of the main weld path defines an inner perimeter and an outer perimeter. The first point is within the inner perimeter, and the outer perimeter defines a closed-loop laser weld. At box 1008, the laser is scanned along an ending weld path from the third point to a fourth point, the fourth point being within the inner perimeter.

[0069] Although the elongated portions are shown as linear segments, it is contemplated that other configurations, such as curved segments, may be used. In addition, although the terminal portions are shown as symmetrical, it is contemplated that they may be asymmetrical. In addition, although the intersection 110 is generally shown as a point, it is contemplated that a longer overlap portion may be used.

[0070] Although the welding path 302 is shown and described as a straight scan path, it is contemplated that other patterns or combinations thereof may be used (eg, sinusoidal or trochoidal scan paths).

[0071] Although the described aspects refer to laser welding, it is contemplated that other welding methods may be used. For example, closed loop laser welding 100 may be used in resistance welding and electron beam welding.

[0072] Embodiments of the present disclosure may be described herein according to functions and / or logic block components and various processing steps. It should be understood that such block components may be implemented by one or more hardware, software and / or firmware components configured to perform a specified function. For example, embodiments of the present disclosure may employ various integrated circuit components (e.g., memory elements, digital signal processing elements, logic elements, lookup tables, etc.), which may perform various functions under the control of one or more microprocessors or other control devices. In addition, those skilled in the art will appreciate that embodiments of the present disclosure may be practiced in conjunction with one or more systems, and the systems described herein are merely exemplary embodiments of the present disclosure.

[0073] As will be appreciated by those skilled in the art, the present disclosure is susceptible to various modifications and alternative forms, and some representative embodiments have been illustrated by way of example in the accompanying drawings and described in detail above. However, it should be understood that the novel aspects of the present disclosure are not limited to the specific forms shown in the accompanying drawings. On the contrary, the present disclosure encompasses modifications, equivalents, combinations, sub-combinations, permutations, groupings, and substitutions that fall within the scope and scheme of the present disclosure and are defined by the appended claims.

[0074] As used herein, unless the context clearly dictates otherwise: the words “and” and “or” shall be regarded as both conjunctions and disjuncts, unless the context clearly dictates otherwise; the word “all” means “any and all”; the word “any” means “any and all”; the word “include” means “including but not limited to”; and the singular forms “a”, “an” and “the” include plural referents and vice versa.

[0075] Unless explicitly or clearly indicated by the context (including the appended claims), the numerical values ​​of parameters (such as quantities or conditions) in this specification should be understood as being modified by the term "about", regardless of whether "about" actually appears before the numerical value. The numerical parameters set forth herein and in the appended claims are approximate values, which may vary depending on the desired properties sought to be obtained by the present disclosure. At the very least, and not attempting to limit the application of the doctrine of equivalents to the scope of the claims, each numerical parameter should at least be interpreted in light of the number of reported significant digits and by applying ordinary rounding techniques.

[0076] Approximate words such as “approximately,” “about,” “substantially,” and the like may be used herein to mean, for example, “at, close to, or nearly at,” “within 0-10% of,” “within an acceptable manufacturing tolerance,” or logical combinations thereof.

[0077] Although the scope and limits of the term "about" are readily understood by those of ordinary skill in the art, the term "about" indicates that the stated value or property allows for imprecision. If the imprecision provided by "about" is not understood in this ordinary sense in the art, then "about" at least indicates the variation that may result from ordinary methods of measuring and using such parameters. For example, if not otherwise understood in the art, the term "about" means within 10% (e.g., ±10%) of the stated value.

[0078] Although the scope and limits of the term "substantially" are readily understood by those of ordinary skill in the art, the term "substantially" indicates that a certain degree of imprecision is allowed for the stated value or property. If the imprecision provided by "about" is not understood in this ordinary sense in the art, then "about" at least indicates the variation that may result from the ordinary methods of measuring and using such parameters. For example, if not otherwise understood in the art, the term "substantially" means within 5% (e.g., ±5%) of the specified value.

[0079] It should be understood that the ranges provided herein include the stated range, the sub-ranges within the stated range, and every value within the stated range.

[0080] While the best modes for carrying out the disclosure have been described in detail, those familiar with the art to which this disclosure relates will recognize various alternative designs and embodiments for practicing the disclosure within the scope of the appended claims.

Claims

1. A method comprising: actuating a laser on the substrate at a first point to initiate welding; as well as scanning the laser along a starting welding path from the first point to a second point; scanning the laser along a main weld path from the second point to a third point such that a weld bead of the main weld path defines an inner perimeter and an outer perimeter, the first point being within the inner perimeter and the outer perimeter defining a closed loop laser weld; and The laser is scanned along a finishing weld path from the third point to a fourth point, the fourth point being within the inner perimeter.

2. The method according to claim 1, wherein: The closed-loop laser welding comprises: A first rounded portion and a second rounded portion that are opposite to each other; and A first elongated portion and a second elongated portion are opposite to each other, the first elongated portion connecting a first end of the first rounded portion to a first end of the second rounded portion, and the second elongated portion connecting a second end of the first rounded portion to a second end of the second rounded portion.

3. The method according to claim 2, wherein: The first elongated portion defines a length between the first end of the first rounded portion and the first end of the second rounded portion, and the first rounded portion defines a first radius, wherein a ratio of the length to the first radius is between 2 and 10.

4. The method according to claim 2, wherein: The first elongated portion defines a length between the first end of the first rounded portion and the first end of the second rounded portion, and the first rounded portion defines a first radius, wherein a ratio of the length to the first radius is between 2.5 and 4.

5. The method according to claim 2, wherein: The first elongated portion defines a length between the first end of the first rounded portion and the first end of the second rounded portion, and the first rounded portion defines a first radius, wherein a ratio of the length to the first radius is between 2.5 and 3.

2.

6. The method according to claim 5, wherein: The second point and the third point are on the first elongated portion.

7. The method according to claim 1, wherein: The operating parameters of the laser include: a first set of operating parameters for the initial welding path, the first set of operating parameters comprising a ramp-up from a first laser power to a second laser power; a second set of operating parameters for the main welding path, the second set of operating parameters including the second laser power; and A third set of operating parameters for the ending weld path includes a ramp down from the second laser power to a third laser power.

8. The method according to claim 7, wherein: The third laser power is lower than the first laser power.

9. A closed-loop laser welding method comprising: a first rounded portion and a second rounded portion opposite to each other; a first elongated portion and a second elongated portion opposing each other, the first elongated portion connecting a first end of the first rounded portion to a first end of the second rounded portion, and the second elongated portion connecting a second end of the first rounded portion to a second end of the second rounded portion, thereby forming a perimeter; as well as a first terminal portion and a second terminal portion located within said perimeter, Wherein, the closed-loop laser welding is formed by scanning the laser on the substrate through the first terminal part, the first part of the first extension part, the first chamfered part, the second extension part, the second chamfered part, the second part of the first extension part and the second terminal part in sequence.

10. A component comprising: a first substrate; a second substrate; as well as Closed-loop laser welding, the closed-loop laser welding bonding the first substrate to the second substrate, the closed-loop laser welding comprising: a first rounded portion and a second rounded portion opposite to each other; a first elongated portion and a second elongated portion opposing each other, the first elongated portion connecting a first end of the first rounded portion to a first end of the second rounded portion, and the second elongated portion connecting a second end of the first rounded portion to a second end of the second rounded portion, thereby forming a perimeter; and a first terminal portion and a second terminal portion located within said perimeter, Wherein, the closed-loop laser welding is formed by scanning the laser on the substrate through the first terminal part, the first part of the first extension part, the first chamfered part, the second extension part, the second chamfered part, the second part of the first extension part and the second terminal part in sequence.

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