Tailored blank laser welding product with annular structure, machining method and hot stamping forming component of tailored blank laser welding product

Abstract

The invention discloses a tailored blank laser welding product with an annular structure, a machining method and a hot stamping forming component of the tailored blank laser welding product, the tailored blank laser welding product is provided with at least one pair of collinear welding seams, the two sides of the collinear welding seams are marked as a first part and a second part respectively, and the first part and the second part are provided with a main positioning hole and an auxiliary positioning hole respectively. The connecting line direction between the center of the main positioning hole and the circle center, closest to the center of the main positioning hole, of the auxiliary positioning hole is defined as the X direction, the direction perpendicular to the X direction is defined as the Y direction, and the collinear welding seam is parallel to the Y direction. The tailored blank laser welding product is subjected to hot stamping to obtain a hot stamping forming component, the component is provided with two characteristic holes, each characteristic hole is formed by machining a main positioning hole and an auxiliary positioning hole in the hot stamping process, any point in the two characteristic holes is selected to be connected into a straight line L, and the component is provided with a first welding seam and a second welding seam. And the acute space included angles between four straight lines formed by cross connection of the end points of the two welding seams and the straight line L are close to 90 degrees.

Description

Technical Field

[0001] The invention belongs to the technical field of tailor-made welding, and in particular relates to a laser tailor-made welding product with an annular structure, a processing method and a hot stamping formed component thereof. Background Art

[0002] At present, there are two main production paths for the welding methods of laser-welded products with ring structures: one is the welding path of single-process splicing using special tooling, and the other is the multi-process welding path without tooling. In order to reduce costs, shorten development cycles and improve project flexibility, the latter has become the first choice for technical and production personnel. This path adopts a multi-process welding method, each process completes a single weld, and finally completes the co-linear weld. Among them, the welding of the last two welds needs to make up for the accumulated deviations of all previous processes, which puts high demands on the welding process.

[0003] At least two collinear welds should be designed during the product design phase and welded as the last two welds in the welding process. In addition, during the welding process of non-collinear welds, errors will accumulate, eventually resulting in the two welding edges on the same side of the collinear weld not being collinear. Therefore, before welding the collinear welds, it is necessary to shear the welded pieces on both sides of the collinear welds to ensure that the welding edges are collinear, thereby minimizing the gap after the welding edges on both sides of the collinear welds are joined. However, during the production process, it was found that the contour of the annular structure laser-welded products was tested based on the main and secondary positioning holes on the pieces, and these positioning holes were not the reference for the previous welding and shearing positioning. Taking into account the deviations in the previous blanking and welding processes, the contour deviation of the finished product is often large, even up to ±5mm, which cannot meet the ±3mm requirement of the industry standard. Summary of the invention

[0004] In view of the above-mentioned deficiencies in the prior art, the present invention provides a linear laser welding product with an annular structure and a processing method thereof, as well as a laser welding component formed by hot stamping. The product is made by welding two corresponding parts through a colinear weld, and the corresponding parts are obtained by shearing the sheared parts. The present invention optimizes the product design and the processing method, which can significantly improve the contour dimensional accuracy of the final product of the tooling-free welding process and meet the high-precision requirements. Specifically, the distance deviation of the main and auxiliary positioning holes does not exceed 2mm, and the product contour deviation is not more than 3mm.

[0005] The technical solution of the present invention is:

[0006] The present invention provides a laser-welded product with an annular structure, which includes a number n of laser-welded welds:

[0007] Among them, 2≤n≤6,

[0008] The product has at least one pair of co-linear welds,

[0009] The two sides of the collinear weld are respectively marked as a first component and a second component, the first component and the second component are respectively provided with a main positioning hole and a secondary positioning hole, the direction of a line between the center of the main positioning hole and the center of a circle in the secondary positioning hole closest to the center of the main positioning hole is defined as an X direction, and a direction perpendicular to the X direction is defined as a Y direction;

[0010] The characteristic is that the collinear weld is parallel to the Y direction, and at this time, the hole distance deviation between the primary and secondary positioning holes is the smallest.

[0011] Preferably, there is no laser tailored weld between the main positioning hole or the auxiliary positioning hole and one of the welds of the collinear welds.

[0012] Preferably, there is a laser tailored weld between the main positioning hole or the auxiliary positioning hole and one of the collinear welds, and the weld is parallel to the Y direction.

[0013] Preferably, there is a straight line profile parallel to the X direction with a length greater than or equal to 30 mm on both the first component and the second component. The straight line profile is used in conjunction with the Y-direction mechanical limiter used during the welding stage of the collinear weld. During the welding stage of the collinear weld, the Y-direction positioning generally uses a mechanical limiter as the alignment reference of the components on both sides of the weld. The Y-direction mechanical limiter used above is the component that plays the role of the Y-direction limiter in the mechanical limiter method.

[0014] The pieces where the main positioning holes and the auxiliary positioning holes are located are recorded as positioning reference pieces. The design requirements for the above straight line profile position are:

[0015] When a straight line profile parallel to the X direction can be provided on the positioning reference sheet, the straight line profile is provided on the corresponding positioning reference sheet;

[0016] When a straight contour parallel to the X-direction cannot be set on the positioning reference sheet, the straight contour is set on the other side sub-sheet of the component that is connected to the corresponding positioning reference sheet through a non-collinear weld, and it is necessary to ensure that the angle between the corresponding non-collinear weld and the X-direction is the smaller one of the two non-collinear welds connected to the positioning reference sheet.

[0017] Preferably, there is no weld between the straight line profile and the corresponding main positioning hole or auxiliary positioning hole.

[0018] Preferably, the center of gravity of any of the first component and the second component intersects with the straight line drawn along the Y direction and the straight line contour on the component. During the welding process of the collinear weld, the component is transported along the Y direction, and the collision with the mechanical limit in the Y direction is likely to cause the sheet to rotate. In order to minimize this rotation, it is preferred to design at least one point on the straight line contour to be collinear with the center of gravity of the component where the straight line contour feature is located in the Y direction.

[0019] The present invention also provides a processing method for a laser-welded product having a ring structure, which is used for the above-mentioned laser-welded product, and the specific steps are as follows:

[0020] Step 1: Processing the first component and the second component;

[0021] Step 2: The edges to be welded of the first component and the second component are assembled to form a ring-shaped structure, and laser welding is performed along a straight line to form a laser welded product with a ring-shaped structure.

[0022] Preferably, in step 1, the colinear edges to be welded of the first component and the second component are obtained by shearing based on sheared pieces.

[0023] Preferably, of the collinear edges to be welded of the first component and the second component, one of the collinear edges to be welded of any component is a shearing reference edge, and the other collinear edge to be welded is a non-shearing reference edge, and a post-shearing platform in the X direction is provided on the sheet inside the non-shearing reference edge;

[0024] The shearing piece is provided with a pre-shearing platform in the X direction, a first shearing allowance platform in the X direction and a second shearing allowance platform in the X direction, the length of the first shearing allowance platform in the X direction is H1, the length of the second shearing allowance platform in the X direction is H2, and the length of H2 is greater than the length of H1;

[0025] The X-direction pre-shearing platform and the X-direction first shearing allowance platform are located on the sheet where the non-shearing reference edge is processed, and the X-direction second shearing allowance platform is located on the sheet where the shearing reference edge is processed; the side edge of the X-direction second shearing allowance platform on the outer side is the shearing positioning reference edge, and the shearing positioning reference edge is parallel to the shearing reference edge and the distance between them is H2;

[0026] After shearing along a shearing line colinear with the shearing reference edge, the second shearing allowance platform in the X-direction is sheared off, and the remaining parts of the pre-shearing platform in the X-direction and the first shearing allowance platform in the X-direction after shearing are the post-shearing platform in the X-direction of the corresponding first component or second component.

[0027] Preferably, the cutting reference edge meets the following requirements:

[0028] When the positioning reference sheet is the sheet where the collinear weld is located, the shear reference edge is the edge to be welded on the positioning reference sheet;

[0029] When the positioning reference sheet is a sheet where a non-collinear weld is located, if the positioning reference sheet is connected to other sheets through a Y-direction non-collinear weld, the shear reference edge is the edge to be welded of the sheet connected to the corresponding positioning reference sheet through a Y-direction non-collinear weld. That is, the sheet where the shear reference edge is located should be selected from the sheet where the edge to be welded of the collinear weld has a higher position accuracy in the X direction relative to the primary and secondary positioning holes, preferably shared with the positioning reference sheet, and secondly, the sheet where the shear reference is located and the positioning reference sheet are connected through a Y-direction weld.

[0030] Preferably, the pre-shearing platform and the first shearing margin platform parallel to the X-direction have a colinear X-direction straight line profile, and the point generated by the intersection of the corresponding X-direction straight line profile and the shearing line is the end point of the final edge to be welded.

[0031] Preferably, the length of the pre-shearing platform in the X direction is L 0 , L 0 Satisfies the following relationship:

[0032]

[0033] Wherein, a is the maximum deviation value of the weld on the corresponding first component or second component obtained in step 1, b is the safety margin, and the units of a and b are mm;

[0034] N is the number of welds on the corresponding first component or second component obtained in step 1, and N ≥ 1;

[0035] θ i is the angle between the i-th weld on the corresponding first component or second component obtained in step 1 and the X direction;

[0036] H2 and H1 satisfy the following relationship:

[0037] H1≥L0, and H2-H1≥5mm.

[0038] Even when the shear line on the sheet of the non-shearing reference edge moves in the X direction, the existence of the pre-shearing platform parallel to the X direction will not cause the intersection of the shear line and the contour edge to deviate in the Y direction, thus avoiding the shearing process introducing Y-direction deviation and causing more serious misalignment in the collinear weld welding process.

[0039] In order to ensure that the actual shear line position is the same as the designed position, the present invention sets the shear reference edge and the shear margin, and the shear margin of the sheet where the shear reference edge is designed to be greater than the shear margin of the sheet where the non-shear reference edge is located. When the shear reference edge is the edge to be welded on the positioning reference sheet, the above margin design can avoid the influence of the previous welding deviation on the shear progress of the non-shear reference edge. When the shear reference edge is the edge to be welded of the sheet connected to the positioning reference sheet by a Y-direction non-collinear weld, the previous welding deviation does not affect the X-direction distance.

[0040] Preferably, in step 2, the first component and the second component are both provided with a straight line profile parallel to the X-direction with a length greater than or equal to 30 mm, the straight line profile is offset against the Y-direction mechanical limit on the welding equipment to achieve Y-direction positioning and splicing to form a ring structure, and laser welding is performed along the straight line to form a laser welded product with a ring structure.

[0041] Preferably, step 1 also includes a design stage of the shearing piece. For the sheet where the shearing reference edge is located, the edge to be welded is translated outwardly along the X direction by a length H2. For the sheet where the non-shearing reference edge is located, the edge to be welded has a shearing front platform feature. At the same time, the outer side of the front platform is translated outwardly along the X direction by a length H1.

[0042] The present invention also provides a laser-welded hot stamping formed component with an annular structure, wherein the component is obtained by hot stamping the aforementioned linear laser-welded product with an annular structure. Hot stamping involves heating a blank to a temperature at which the microstructure of the steel is at least partially transformed into austenite, thereby forming the blank at a high temperature by stamping the blank, and quenching the formed part to obtain a microstructure with high strength.

[0043] Preferably, the microstructure is substantially martensitic, ie comprises at least 95% martensite and at most 5% bainite and / or ferrite by volume. More preferably, the microstructure is fully martensitic.

[0044] Preferably, the hot stamping formed component comprises a coating on at least one side of the steel substrate. More preferably, the coating is an aluminum alloy coating. The coating comprises aluminum and iron, and preferably also comprises silicon. During hot stamping, the aluminum alloy pre-coating layer and the steel diffuse inter-diffusion, and the coating after hot stamping comprises an inter-diffusion layer and an outer layer extending from the diffusion layer to the surface of the coating. The inter-diffusion layer is located at the innermost side of the coating, i.e., in contact with the steel substrate, and the outer layer generally comprises or consists of an inter-metallic compound of Fe, Al and possibly Si.

[0045] In the state of the welded part before stamping, the two collinear welds are located on the same straight line in the same plane. During the stamping process, the main and secondary positioning holes of the stamping basically maintain their relative positions unchanged, and the materials in other parts undergo plastic deformation to form a 3D structure. In this process, the weld will change from a straight line to a 3D curve, and the two endpoints of the two welds are approximately distributed on the same straight line. The collinear welds on the welded product become the corresponding first weld and second weld after stamping. In addition, after stamping, the main and secondary positioning holes on the welded product are squeezed by the positioning pins on the stamping die, which will produce a certain deformation. Often, a larger feature hole is cut on the hot stamping formed component around the corresponding positioning hole to eliminate the stamping deformation area of ​​the positioning hole, and the expansion distance generally does not exceed 8mm.

[0046] The beneficial effects of the present invention are:

[0047] (1) The present invention preferably designs the connection direction of the collinear weld to be perpendicular to the connection direction of the primary and secondary positioning holes, which helps to improve the distance accuracy of the primary and secondary positioning holes and reduce the X-direction positioning deviation;

[0048] (2) The present invention further designs that the first component and the second component have a straight line profile feature in the X direction, which is used in conjunction with the mechanical limit in the Y direction to help reduce the positioning deviation in the Y direction;

[0049] (3) The present invention selects a suitable edge to be welded as the shearing reference edge. The sheet where the shearing reference edge is located should be selected to have a high X-direction position accuracy of the edge to be welded relative to the primary and secondary positioning holes, and the X-direction pre-shearing platform and the first shearing margin platform have a collinear X-direction straight line profile feature, which helps to ensure the Y-direction position of the edge to be welded after shearing, avoids the Y-direction deviation introduced in the shearing process, and causes the misalignment of the collinear weld in the welding process to be more serious, thereby reducing the misalignment of the contours on both sides of the collinear weld in the Y direction;

[0050] (4) The present invention has specially designed the shearing piece for processing the parts of the collinear weld, requiring that the length of the second shearing margin platform in the X direction of the sheet where the shearing reference edge is located is greater than the length of the first shearing margin platform in the X direction of the sheet where the non-shearing reference edge is located, and the side edge of the second shearing margin platform on the outer side is the shearing positioning reference edge. During the shearing process, the shearing positioning reference edge is ensured to be the only part that fits the rear positioning baffle of the shearing machine, which helps to ensure that the actual shear line position is the position of the shearing reference edge;

[0051] (5) According to the design and processing method of the present invention, the distance deviation of the primary and secondary positioning holes of the laser-welded product can be controlled within ±2 mm, and the product contour deviation can be controlled within ±3 mm. BRIEF DESCRIPTION OF THE DRAWINGS

[0052] The present invention will be further described below in conjunction with the accompanying drawings and embodiments:

[0053] Figure 1 This is an enlarged schematic diagram of the primary and secondary positioning holes;

[0054] Figure 2 This is a schematic diagram of the calculation of the effect of misalignment on hole spacing tolerance zone D;

[0055] Figure 3 It is a schematic diagram of different design positions of the positioning part;

[0056] Figure 4 It is a schematic diagram of the platform after shearing in the X direction;

[0057] Figure 5 Schematic diagram of the shearing position;

[0058] Figure 6 This is a schematic diagram of the structure of the first component and the second component of Example 1;

[0059] Figure 7 is a schematic diagram of two shearing pieces of Example 1;

[0060] Figure 8 This is a schematic structural diagram of a product obtained by welding two components of Example 1 together in a collinear manner;

[0061] Fig. 9 This is a schematic diagram of a hot stamping component of Example 3;

[0062] Fig.10 A schematic diagram of a laser welded product corresponding to the hot stamping formed component of Example 3;

[0063] Fig.11 for Fig. 9 A schematic diagram of the right characteristic hole of the hot stamping formed component of Example 3;

[0064] Fig.12 for Fig. 9 Schematic diagram of the left characteristic hole of the hot stamping formed component in Example 3.

[0065] The markings in the figure are: 1. Main positioning hole; 2. Auxiliary positioning hole; 3. Mechanical limit in Y direction; 4. Positioning part; 5. Post-shearing platform in X direction; 6. Pre-shearing platform in X direction; 7. First shearing allowance platform in X direction; 8. Second shearing allowance platform in X direction. DETAILED DESCRIPTION

[0066] In order to make the purpose, technical scheme and advantages of the present invention clearer, the present invention is further described in detail below in conjunction with specific embodiments and with reference to the accompanying drawings. It should be understood that these descriptions are only exemplary and are not intended to limit the scope of the present invention. In addition, in the following description, the description of well-known structures and technologies is omitted to avoid unnecessary confusion of the concept of the present invention.

[0067] A laser-welded product with an annular structure has at least one pair of collinear welds and is manufactured by welding a first component and a second component on both sides of the pair of collinear welds along the collinear welds, wherein the components are manufactured by shearing corresponding shearing pieces.

[0068] A main positioning hole and a secondary positioning hole are respectively provided on the first component and the second component, and the sheets where the main positioning hole and the secondary positioning hole are located are both recorded as positioning reference sheets.

[0069] The direction of the line between the center of the main positioning hole and the center of the circle closest to the center of the auxiliary positioning hole is defined as the X direction, and the direction perpendicular to the line is defined as the Y direction. Generally, the main positioning hole is a round hole or a plum blossom hole with multiple symmetrically distributed notches on the circular edge, and the other auxiliary positioning hole is a waist-shaped hole. In actual use, the positioning hole may be squeezed and deformed by the positioning pin. In the final product, a larger square hole, round hole, or special-shaped hole can be cut around the contour of the positioning hole. Figure 1 As shown, the main positioning hole is a circular hole with one center, which is its center, and the auxiliary positioning hole is a waist-shaped hole with two centers. The X direction is the direction of the line connecting the center of the main positioning hole and the center of the auxiliary positioning hole close to the main positioning hole.

[0070] The distance between the center of the main positioning hole and the center of the secondary positioning hole on the side close to the main positioning hole is recorded as the hole distance. The hole distance is one of the important parameters of the laser welding product of the present invention. Under normal circumstances, the distance between the main and secondary positioning holes is about 1100mm, or even larger. If the hole distance deviation exceeds the tolerance range, the heated sheet during the stamping process will not be able to be put into the mold, which will lead to production line shutdown and economic losses. If the misalignment deviation in the welding process cannot be avoided, the impact of the misalignment deviation on the distance between the main and secondary positioning holes should be reduced.

[0071] The present invention requires that the direction of the line between the center of the main positioning hole and the center of the auxiliary positioning hole closest to the main positioning hole is perpendicular to the weld, at which time the hole distance deviation between the main and auxiliary positioning holes is minimal.

[0072] For the convenience of description, Figure 2 The secondary positioning long hole in the figure is simplified to a circle close to the main positioning hole. During the welding process of the collinear weld, the misalignment deviation is mainly along the straight line direction of the collinear weld, which is equivalent to taking the sheet where the main positioning hole is located as the reference, and moving the secondary positioning hole from the center of the circle along the collinear weld by the misalignment amount. The maximum misalignment amount is d, and the angle α between the moving direction and the X direction makes the hole spacing change from the designed L to L'. Figure 2As shown, assuming that the tolerance width of the hole spacing is D, this tolerance zone is the deviation between the maximum and minimum hole spacing when the auxiliary positioning hole is in all possible positions. All actual hole spacings L' can be projected to the X direction to form a triangle with hypotenuse L' and right angles L" and d. Because the designed hole spacing L is much larger than d, it is approximately considered that L'=L", then there is

[0073] D=L' max -L' min =L" max -L" min =2d·cosα

[0074] When cosα=0, that is, the angle α is 90°, D is the smallest, so the closer the collinear weld is to being parallel to the Y direction, the smaller the effect of the misalignment deviation on the distance between the primary and secondary locating holes.

[0075] During the welding stage of the collinear weld, it is necessary to eliminate the influence of the Y-direction deviation accumulated in the previous welding on the Y-direction positioning of the first component and the second component during the collinear weld. During the welding stage of the collinear weld, the Y-direction positioning uses a mechanical limiter as the alignment reference for the pieces on both sides of the collinear weld. The deviation of the contour edge in the Y-direction relative to the positioning hole that matches this limiter determines the positioning accuracy of the overall piece in the Y-direction. The Y-direction mechanical limiter is the component that plays the role of the Y-direction limiter in the mechanical limiter method.

[0076] The first component and the second component are both provided with a positioning portion used in conjunction with the Y-direction mechanical limiter, the positioning portion has a straight line profile feature in the X direction, and the length of the straight line profile is at least 30 mm.

[0077] Taking one of the components as an example, the position design requirements of the straight line profile in the X direction are as follows:

[0078] like Figure 3 As shown in A, when a straight line profile can be set on the positioning reference sheet, the straight line profile is set on the corresponding positioning reference sheet;

[0079] like Figure 3 As shown in B, when a straight contour cannot be set on the positioning reference sheet, the straight contour is set on the other side sheet connected to the positioning reference sheet through a non-collinear weld, and it is necessary to ensure that the angle between the corresponding non-collinear weld and the X-axis is the smaller angle of the two non-collinear welds connected to the positioning reference sheet.

[0080] Further preferably, Figure 3 As shown in C, at least one point on the straight contour is parallel to the line connecting the center of gravity of the component where the contour is located and the collinear weld, so that when the two components are moved, the components are not easy to rotate when they contact the Y-axis mechanical limit, ensuring process efficiency and accuracy. In addition, when the above design requirements are met, the deviation between this straight contour feature and the positioning hole in the Y direction is only the blanking deviation, with the highest accuracy.

[0081] The first component and the second component of the present invention are obtained by shearing corresponding shearing pieces. The commonly used shearing method is to pass the sheared sheet under the cutting edge of the shearing machine, and to fit the corresponding two edges to the positioning baffle behind the cutting edge to complete the shearing. The non-colinearity of the corresponding two edges will cause the shearing line direction to be non-parallel to the designed colinear weld line direction.

[0082] To this end, the present invention selects one of the two edges to be welded on the same component as a shear reference edge and the other as a non-shear reference edge. The sheet on the inner side of the edge to be welded corresponding to the non-shear reference edge is provided with an X-direction post-shearing platform, such as Figure 4 and Figure 6 shown.

[0083] The edge to be welded selected as the cutting reference edge must meet the following requirements:

[0084] When the positioning reference sheet is the sheet where the collinear weld is located, the shearing reference edge is the edge to be welded on the corresponding positioning reference sheet, that is, the edge to be welded and the corresponding primary or secondary positioning hole are located on the same sheet, which results in the highest accuracy;

[0085] When the positioning reference sheet is the sheet where the non-collinear weld is located, if the positioning reference sheet is connected to the sheet through a Y-direction non-collinear weld, then the shear reference edge is the edge to be welded of the sheet that is connected to the corresponding positioning reference sheet through a Y-direction non-collinear weld.

[0086] The first part and the second part are obtained by cutting the corresponding shearing pieces along the shearing line that is colinear with the shearing reference edge. The shearing position is as follows: Figure 5 The corresponding shearing piece is provided with a pre-shearing platform in the X direction, a first shearing allowance platform in the X direction and a second shearing allowance platform in the X direction. The length of the first shearing allowance platform in the X direction is H1, and the length of the second shearing allowance platform in the X direction is H2. H2 is the design shearing allowance of the sheet where the shearing reference edge is located, and H1 is the design shearing allowance of the sheet where the non-shearing reference edge is located.

[0087] The X-direction pre-shear platform and the X-direction first shear allowance platform are located at the material piece where the non-shearing reference edge is processed, the X-direction second shear allowance platform is located at the material piece where the shearing reference edge is processed, and the outer side of the X-direction second shear allowance platform is the shear positioning reference edge, which is parallel to the shearing reference edge.

[0088] The length of the platform before shearing in the X direction is L 0 , L 0 Satisfies the following relationship:

[0089]

[0090] Wherein, a is the maximum deviation value of the weld on the corresponding first component or second component, b is the safety margin, and the units of a and b are mm;

[0091] N is the number of welds on the corresponding first component or second component, and N ≥ 1;

[0092] θ i is the angle between the i-th weld on the corresponding first component or second component and the X direction. The weld portion mentioned above does not include the colinear weld corresponding to the colinear weld welding of the first component and the second component.

[0093] After the shearing piece is sheared along the shearing line that is colinear with the shearing reference edge, the second shearing allowance platform in the X direction is sheared off, and the shearing length is H2. The remaining part of the X-direction front shearing platform and the X-direction first shearing allowance platform after shearing is the X-direction rear shearing platform.

[0094] When actual shearing occurs, the shear line may intrude into the originally designed product. To ensure that the actual shear line position is the same as the designed position, the present invention designs a shear margin platform, thereby ensuring that the position of the to-be-welded edge of the actual collinear weld is fully controlled. The shear margin platform lengths H2 and H1 satisfy the following relationship:

[0095] H1≥L 0 , and H2-H1≥5mm.

[0096] Preferably, the X-direction pre-shearing platform of the shearing piece and the X-direction first shearing allowance platform have a collinear X-direction straight line profile, and the point generated by the intersection of the corresponding X-direction straight line profile and the shearing line is the end point of the final edge to be welded. Because the X-direction straight line segment has only one coordinate in the Y direction, no matter how the shearing line moves in the X direction, it will not affect the position of the endpoint in the Y direction, thereby ensuring the Y-direction position of the edge to be welded after shearing, that is, avoiding the shearing process introducing Y-direction deviation and aggravating the misalignment phenomenon in the collinear weld welding process.

[0097] During the production process, the actual position of the shear line on the sheet where the non-shearing reference edge is located will be offset to both sides. The shearing that is offset to the inside is absorbed by the front shearing platform on the shearing piece, and the shearing that is offset to the outside is absorbed by the first shearing allowance platform in the X direction, thus ensuring that all possible shear line positions are on the straight line contour in the X direction.

[0098] The processing method of the above-mentioned linear laser welding product with an annular structure comprises the following steps:

[0099] (1) Design and process each piece, complete the welding of all welds except a pair of collinear welds, and form a shear part;

[0100] (2) placing the shearing piece on a shearing machine for shearing to form a first component and a second component, wherein the shearing positioning reference edge is the only part that is in contact with the rear positioning baffle of the shearing machine during the shearing process, and the shearing length of the sheet where the shearing positioning reference edge is located is H2;

[0101] (3) The first component and the second component are welded along a common weld to form a linear laser welding product having a ring-shaped structure.

[0102] The present invention can significantly improve the contour dimensional accuracy of laser-welded products in a tooling-free welding process, with the distance deviation between the primary and secondary positioning holes not exceeding 2 mm, and the contour deviation of the product not exceeding 3 mm.

[0103] Example 1

[0104] like Figure 6-8 As shown, this embodiment provides a linear laser welding product with an annular structure and a shearing piece for processing the same. The first component and the second component are welded by a colinear weld to form a welded product, and the two shearing pieces are sheared to obtain corresponding components.

[0105] like Figure 8 As shown, the product of this embodiment has 5 welds, including a pair of collinear welds, and the angle between the line connecting the center of the main positioning hole and the center of the secondary positioning hole near the main positioning hole and the line connecting the collinear welds is 90°. The first component on the left side of the product is welded by 3 sub-sheets, one of which is the positioning reference sheet, and the other two are sheets where the edges of the collinear welds to be welded are located. The second component on the right side is welded by 2 sheets, one of which is both the positioning reference sheet and the sheet where the edges of the collinear welds to be welded are located.

[0106] like Figure 6 As shown, the first component and the second component of this embodiment are both provided with a positioning part used in conjunction with the Y-direction mechanical limiter, and the positioning part has a straight line profile feature in the X-direction, and the length is 30 mm. Specifically, on the first component on the left, the straight line profile of the positioning part in the X-direction is set on the positioning reference sheet where the secondary positioning hole is located, and on the second component on the right, the straight line profile of the positioning part in the X-direction is also set on the positioning reference sheet where the main positioning hole is located, and at least one point on the straight line profile of the positioning part in the X-direction is parallel to the centroid line of the component where the profile is located and the collinear weld. Figure 6 The enlarged views of C1 and C2 in FIG. 1 are enlarged views of the corresponding positioning parts.

[0107] for Figure 6 For the first component on the left side, the corresponding positioning reference sheet is the sheet where the non-collinear weld is located, and the shearing reference edge is the edge of the sheet to be welded that is connected to the corresponding positioning reference sheet through a Y-direction non-collinear weld. Figure 6For the second component on the right side, the corresponding positioning reference sheet is the sheet where the collinear weld is located. Therefore, the edge to be welded on the corresponding positioning reference sheet is selected as the shearing reference edge. Figure 6 The components on the left and right sides of the i The value of and the corresponding cosθ i The values ​​are shown in Table 1 below:

[0108] Table 1

[0109] <![CDATA[θ 1 ]]> <![CDATA[θ 2 ]]> <![CDATA[cosθ 1 ]]> <![CDATA[cosθ 2 ]]> First component 27° 90° 0.89 0.00 Second component 9° 0.99

[0110] The corresponding shear parts are Figure 7 As shown, an X-direction pre-shearing platform, an X-direction first shearing allowance platform and an X-direction second shearing allowance platform are provided thereon, the X-direction pre-shearing platform and the X-direction first shearing allowance platform are located on the sheet where the processing non-shearing reference edge is located, the X-direction second shearing allowance platform is located on the sheet where the processing shearing reference edge is located, and the X-direction pre-shearing platform and the corresponding X-direction first shearing allowance platform have a colinear X-direction straight line profile.

[0111] In the product of the present invention, the misalignment amount that may be produced by each non-collinear weld fluctuates within the range of ±2mm, and the negative sign represents the direction of the deviation. The corresponding maximum deviation value a=2mm. To prevent some abnormal situations from occurring, the safety margin is selected to be 5mm, that is, b=5mm. Therefore, the length L of the platform before shearing in the X direction is 0 The following conditions must be met:

[0112]

[0113] for Figure 7 The shearing piece corresponding to the first component on the left side has a platform length of 7 mm before shearing in the X direction, which satisfies L 0 ≥2*(cos27°+cos90°)+5. In addition, H1=7mm, H2=12mm.

[0114] for Figure 7 The shearing piece corresponding to the second part on the right side has a platform length of 7 mm before shearing in the X direction, which also satisfies L 0 ≥2*cos9°+5. In addition, H1=7mm, H2=12mm.

[0115] During the shearing process, the shearing piece will be sheared along the shearing line that is colinear with the shearing reference edge. The shearing length is H2, i.e. 12 mm. Therefore, the remaining platform length of the obtained component on the shearing reference side is 0 mm, i.e. the second shearing margin platform in the X direction is sheared off to form the shearing reference edge.

[0116] The remaining part of the X-direction pre-shearing platform and the X-direction first shearing allowance platform after shearing is the X-direction post-shearing platform of the corresponding first component or second component, and the X-direction post-shearing platform is located on the inner side of the formed non-shearing reference edge.

[0117] like Figure 8 As shown, for the first component on the left, when the accumulated misalignment deviation in the X direction is r=1.5 mm, the corresponding post-shearing platform length in the X direction is 5.5 mm.

[0118] For the second component on the right side, when the accumulated misalignment deviation in the X direction is r=-0.5 mm, the corresponding post-shearing platform length in the X direction is 7.5 mm.

[0119] Example 2

[0120] The processing method of the linear laser welding product with an annular structure of the above-mentioned embodiment 1 comprises the following steps:

[0121] (1) Design and process each piece, complete the welding of all welds except a pair of collinear welds, and form a shear part;

[0122] The shearing piece is provided with a pre-shearing platform in the X direction, a first shearing allowance platform in the X direction and a second shearing allowance platform in the X direction. The side edge of the second shearing allowance platform in the X direction on the outer side is the shearing positioning reference edge. The length of the pre-shearing platform in the X direction is 7 mm, the first shearing allowance platform in the X direction is 7 mm, and the second shearing allowance platform in the X direction is 12 mm.

[0123] (2) placing the shearing piece on a shearing machine for shearing to form a first component and a second component, wherein the shearing positioning reference edge is the only part that is in contact with the rear positioning baffle of the shearing machine during the shearing process, and the shearing length of the sheet where the shearing positioning reference is located is 12 mm; after the shearing is completed, the second shearing margin platform in the X direction of the shearing piece is sheared off, and the remaining parts of the X-direction pre-shearing platform and the X-direction first shearing margin platform after shearing are the X-direction post-shearing platform corresponding to the first component or the second component;

[0124] The X-direction pre-shearing platform and the corresponding X-direction first shearing allowance platform have a colinear X-direction straight line profile. During the shearing process, the actual position of the shearing line on the sheet where the non-shearing reference edge is located will be offset to both sides. The shearing that is offset to the inside is absorbed by the pre-shearing platform on the shearing piece, and the shearing that is offset to the outside is absorbed by the X-direction first shearing allowance platform, thereby ensuring that all possible shearing line positions are on the X-direction straight line profile.

[0125] (3) The first component and the second component obtained in step (2) are placed on a welding device for welding of a colinear weld. During the welding process, the straight line contour features on each component offset the Y-direction mechanical limit on the welding device to complete the positioning of the corresponding component in the Y direction.

[0126] Example 3

[0127] According to the design and processing scheme of the present invention, the following can be obtained: Fig.10 A linear laser welding product with an annular structure is shown in the figure. The welded product is subsequently processed by hot stamping and other processes, and a pair of collinear straight welds on the welded product become as follows after hot stamping. Fig. 9 The first and second welds of the 3D curve on the part shown, the endpoints of the first and second welds on the proximal side are defined as A and B respectively, and the distal endpoints are defined as A' and B'. The four endpoints are cross-connected to obtain four straight lines AB, A'B', AB' and A'B. After stamping, the main and auxiliary positioning holes on the welded product are squeezed by the positioning pins on the stamping die, which will produce a certain deformation. A larger characteristic hole is cut on the hot stamping formed component around the corresponding positioning hole to eliminate the stamping deformation area of ​​the positioning hole, and the enlarged distance is generally not more than 8mm.

[0128] In the actual automobile parts processing process, the characteristic holes on the A-pillar and the B-pillar correspond to the primary and secondary positioning holes of the original tailor-welded product. A point is randomly selected on the surface surrounded by the inner contour of the characteristic hole, and the distance between this point and the edge contour is greater than 8 mm. This embodiment calculates the offset of the straight weld of the weld after stamping through simulation, such as Fig. 9 As shown, the straight line L is obtained by connecting the two points of the two characteristic holes. The angles between the four straight lines formed by the intersection of the first weld and the second weld end points and L are 87°, 86°, 87°, and 87°, respectively, and the deviation from 90° is within 5°. The shortest distances between the corresponding L line end points in the characteristic holes on both sides and the internal contour of the holes are 20mm and 23.1mm, respectively, both greater than 8mm.

[0129] It should be understood that the above specific embodiments of the present invention are only used to illustrate or explain the principles of the present invention, and do not constitute a limitation of the present invention. Therefore, any modifications, equivalent substitutions, improvements, etc. made without departing from the spirit and scope of the present invention should be included in the protection scope of the present invention. In addition, the appended claims of the present invention are intended to cover all changes and modifications that fall within the scope and boundaries of the appended claims, or the equivalent forms of such scope and boundaries.

Claims

1. A laser-welded product with an annular structure, comprising n laser-welded welds: in, 2≤n≤6， The product has at least one pair of co-linear welds, The two sides of the collinear weld are respectively marked as a first component and a second component, the first component and the second component are respectively provided with a main positioning hole and a secondary positioning hole, the direction of a line between the center of the main positioning hole and the center of a circle in the secondary positioning hole closest to the center of the main positioning hole is defined as an X direction, and a direction perpendicular to the X direction is defined as a Y direction; The invention is characterized in that the collinear weld is parallel to the Y direction.

2. The laser welding product according to claim 1, characterized in that: There is no laser tailored weld between the main positioning hole or the auxiliary positioning hole and one of the welds of the collinear welds.

3. The laser welded product according to claim 1, characterized in that: There is a laser tailored weld between the main positioning hole or the auxiliary positioning hole and one of the collinear welds, and the weld is parallel to the Y direction.

4. The laser welded product according to any one of claims 1 to 3, characterized in that: Both the first component and the second component have a straight line profile parallel to the X direction with a length greater than or equal to 30 mm.

5. The laser welded product according to claim 4, characterized in that: There is no weld between the straight line profile and the corresponding main positioning hole or auxiliary positioning hole.

6. The laser welded product according to claim 4, characterized in that: A straight line drawn along the Y direction from the center of gravity of any one of the first component and the second component intersects a straight line contour on the component.

7. A hot stamping component with an annular structure, which is formed by hot stamping the laser welded product according to any one of claims 1 to 6, wherein the component has two characteristic holes, which are formed by the main and auxiliary positioning holes in the hot stamping process, and is characterized in that: The component has a first weld and a second weld, the endpoints of the first weld and the second weld on the proximal side are defined as A and B respectively, the distal endpoints are defined as A' and B', and a point is randomly selected from the two characteristic holes to connect them into a straight line L, and the acute angle between the straight line L and the straight lines AB, A'B', AB' and A'B is 80 to 90°.

8. The hot stamping component according to claim 7, wherein the endpoints of the straight line L are located in two corresponding holes of the characteristic holes and are any points that are more than 8 mm away from the edge.

9. The hot stamping formed component according to claim 7 or 8, characterized in that: The acute spatial angles formed by the straight line L and the straight lines AB, A'B', AB' and A'B are 85-90 degrees.

10. A method for processing a laser-welded product having a ring structure, for processing the laser-welded product according to any one of claims 1 to 6, the specific steps of which are: Step 1: Processing the first component and the second component; Step 2: The edges to be welded of the first component and the second component are assembled to form a ring-shaped structure, and laser welding is performed along a straight line to form a laser welded product with a ring-shaped structure.

11. The processing method according to claim 10, characterized in that: In step 1, the colinear edges to be welded of the first component and the second component are obtained by shearing based on the sheared pieces.

12. The processing method according to claim 11, wherein step 1 is characterized in that, of the collinear edges to be welded of the first component and the second component, one of the collinear edges to be welded of any component is a shearing reference edge, and the other collinear edge to be welded is a non-shearing reference edge, and a post-shearing platform in the X direction is provided on the sheet inside the non-shearing reference edge; The shearing piece is provided with a pre-shearing platform in the X direction, a first shearing allowance platform in the X direction and a second shearing allowance platform in the X direction, the length of the first shearing allowance platform in the X direction is H1, the length of the second shearing allowance platform in the X direction is H2, and the length of H2 is greater than the length of H1; The X-direction pre-shearing platform and the X-direction first shearing allowance platform are located on the sheet where the non-shearing reference edge is processed, and the X-direction second shearing allowance platform is located on the sheet where the shearing reference edge is processed; the side edge of the X-direction second shearing allowance platform on the outer side is the shearing positioning reference edge, and the shearing positioning reference edge is parallel to the shearing reference edge and the distance between them is H2; After shearing along a shearing line colinear with the shearing reference edge, the second shearing allowance platform in the X-direction is sheared off, and the remaining parts of the pre-shearing platform in the X-direction and the first shearing allowance platform in the X-direction after shearing are the post-shearing platform in the X-direction of the corresponding first component or second component.

13. The processing method according to claim 12, characterized in that: The length of the platform before shearing in the X direction is L0, and L0 satisfies the following relationship: Wherein, a is the maximum deviation value of the weld on the corresponding first component or second component obtained in step 1, b is the safety margin, and the units of a and b are mm; N is the number of welds on the corresponding first component or second component obtained in step 1, and N ≥ 1; θ i is the angle between the i-th weld on the corresponding first component or second component obtained in step 1 and the X direction; H2 and H1 satisfy the following relationship: H1≥L0, and H2-H1≥5mm.

14. The processing method according to claim 10, characterized in that: In step 2, the first component and the second component are both provided with a straight line profile parallel to the X-direction with a length greater than or equal to 30 mm. The straight line profile is offset against the Y-direction mechanical limit on the welding equipment to achieve Y-direction positioning and splicing to form a ring structure, and laser welding is performed along the straight line to form a laser welded product with a ring structure.

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