A method for forming a connection region

Abstract

The present application discloses a method for forming a connection area. The forming method includes the following steps: obtaining a first part process model; performing a splitting process on the first part process model to obtain a first split part and a second split part; there is a connection area between the first split part and the second split part; based on the connection area, obtaining the maximum thickness of the connection area; obtaining a laser powder feeding device; based on the laser powder feeding device, obtaining the powder focus height, powder feeding angle, and cladding head radius of the laser powder feeding device; based on the powder focus height, powder feeding angle, cladding head radius, and the maximum thickness of the connection area, obtaining gradient groove parameters; based on the gradient groove parameters, performing gradient groove machining on the connection area of the first part process model to obtain a connection area simulation model; performing laser powder feeding machining based on the connection area model to obtain a target connection area.

Description

Technical Field

[0001] The present application relates to the technical field of additive manufacturing, and particularly relates to a forming method for a connection region. Background Art

[0002] With the proposal of the integrated design of aircraft and the continuous increase in the size and load capacity of aircraft, the manufacturing demand for large-sized complex components is becoming stronger and stronger. In order to manufacture large-sized complex parts, currently, the laser additive connection split part forming technology is used to solve problems such as limited forming size and large forming deformation of equipment.

[0003] The laser additive connection split part forming technology is a derivative of the laser melting deposition forming technology, which can achieve controllable microstructure morphology in the connection area and minimize the heat affected zone, and solves the problem of the thickness limitation of the connecting parts in the traditional connection method. However, the connection area obtained by printing with existing laser powder feeding 3D printing equipment cannot meet the application requirements. Summary of the Invention

[0004] The main purpose of the present application is to provide a forming method for a connection region, aiming to solve the technical problem that the connection region obtained by printing with existing laser powder feeding 3D printing equipment cannot meet the application requirements.

[0005] To solve the above technical problem, the present application proposes: A forming method for a connection region, comprising the following steps:

[0006] Obtain a first part process model;

[0007] Perform split processing on the first part process model to obtain a first split part and a second split part; wherein there is a connection region between the first split part and the second split part; based on the connection region, obtain the maximum thickness of the connection region;

[0008] Obtain a laser powder feeding device; based on the laser powder feeding device, obtain the powder focus height, powder feeding angle, and cladding head radius of the laser powder feeding device;

[0009] Based on the powder focus height, the powder feeding angle, the cladding head radius, and the maximum thickness of the connection region, obtain gradient groove parameters; wherein the gradient groove parameters include the number of gradient grooves, the gradient transition width, the gradient groove thickness, and the gradient groove angle;

[0010] Based on the gradient groove parameters, perform gradient groove machining on the connection region of the first part process model to obtain a connection region simulation model; perform laser powder feeding machining based on the connection region model to obtain a target connection region.

[0011] As some alternative embodiments of the present application, obtaining the gradient groove parameters based on the powder coke height, the powder feeding angle, the radius of the cladding head, and the maximum thickness of the connection area includes:

[0012] Comparing the powder coke height with the maximum thickness of the connection area to obtain a comparison result;

[0013] Based on the comparison result, the powder feeding angle, the radius of the cladding head, and the maximum thickness of the connection area, obtaining the gradient groove parameters.

[0014] As some alternative embodiments of the present application, if the powder coke height is greater than the maximum thickness of the connection area, the number of gradient grooves is 2, the gradient transition width ≤ 5 mm, and the thickness of the first gradient groove does not exceed one-half of the maximum thickness of the connection area.

[0015] As some alternative embodiments of the present application, if the powder coke height is less than or equal to the maximum thickness of the connection area, the thickness of the first gradient groove connected ≤ 10 mm, and the thickness of the remaining gradient grooves ≤ (powder coke height - 5) mm.

[0016] As some alternative embodiments of the present application, if the powder coke height is less than or equal to the maximum thickness of the connection area, the number of gradient grooves is obtained through the following relational expression:

[0017] Number of gradient grooves > (h - h 1 ) / (H - 5) + 1

[0018] where h represents the maximum thickness of the connection area, H represents the powder coke height, and the h 1 represents the thickness of the first gradient groove connected.

[0019] As some alternative embodiments of the present application, if the powder coke height is less than or equal to the maximum thickness of the connection area, the groove angle β of the first gradient groove connected is 50° - 70°; the groove angle β of other gradient grooves x is: powder feeding angle θ < β x ≤ 45°.

[0020] As some alternative embodiments of the present application, if the powder coke height is less than or equal to the maximum thickness of the connection area, the gradient transition width L of the first gradient groove connected ≤ 5 mm, and the gradient transition width L of other gradient grooves x ≥ maximum radius R of the cladding head - (powder coke height H - 5) * tan β n-1 ; where the β n-1 refers to the groove angle of the nth gradient groove.

[0021] As some alternative embodiments of the present application, before obtaining the first part process model, it includes:

[0022] Based on the application scenario, obtain the part target simulation model;

[0023] Perform simplification processing and thickening processing on the part target simulation model to obtain the first part process model.

[0024] As some alternative embodiments of the present application, the performing simplification processing and thickening processing on the part target simulation model to obtain the first part process model includes:

[0025] After deleting the small features of the part target simulation model, thicken each part surface by ≥5 mm to obtain the first part process model.

[0026] As some alternative embodiments of the present application, the performing gradient groove machining on the connection area of the first part process model based on the gradient groove parameters to obtain the connection area simulation model; performing laser powder feeding machining based on the connection area model to obtain the target connection area includes:

[0027] Perform gradient groove machining on the connection area of the first part process model based on the gradient groove parameters to obtain the connection area simulation model;

[0028] Based on the groove angles of several gradient grooves in the connection area simulation model, obtain the laser powder feeding energy density values of the several gradient grooves;

[0029] Based on the laser powder feeding energy density values, obtain the forming process parameters of the several gradient grooves;

[0030] Perform laser powder feeding machining based on the forming process parameters to obtain the target connection area.

[0031] As some alternative embodiments of the present application, the energy density value is obtained through the following relational expression:

[0032] VED = P / (VHD)

[0033] Wherein, VED represents the energy density value, P represents the laser power, V represents the scanning speed, H represents the layer thickness, and D represents the scanning pitch.

[0034] Since existing laser powder feeding 3D printing devices usually use coaxial powder feeding as the main method, and the powder focus height of the laser coaxial powder feeding cladding head is generally fixed, within 20 - 80 mm for example. Therefore, when laser powder feeding is performed on a relatively thick connection area, the expected effect cannot be achieved. Specifically, the grooves of the connection area are mainly "V" type and "X" type. So, when the groove angle of the connection area is too small, during the laser powder feeding process, the gas at the bottom of the groove cannot overflow, resulting in the gas being trapped in the connection area to form pore defects after solidification, and further leading to poor connection performance of the formed connection area. If the groove angle of the connection area is too large, it will result in a larger connection area and excessive deposition during laser powder feeding, and deformation is likely to occur in the connection area after solidification. Therefore, in view of the above technical problems, the embodiment of the present application proposes a forming method for the connection area, that is: obtaining a first part process model; performing a split process on the first part process model to obtain a first split part and a second split part; there is a connection area between the first split part and the second split part; based on the connection area, obtaining the maximum thickness of the connection area; obtaining a laser powder feeding device; based on the laser powder feeding device, obtaining the powder focus height, powder feeding angle, and cladding head radius of the laser powder feeding device; based on the powder focus height, powder feeding angle, cladding head radius, and the maximum thickness of the connection area, obtaining gradient groove parameters; wherein the gradient groove parameters include the number of gradient grooves, gradient transition width, gradient groove thickness, and gradient groove angle; based on the gradient groove parameters, performing gradient groove machining on the connection area of the first part process model to obtain a connection area simulation model; performing laser powder feeding processing based on the connection area model to obtain a target connection area. It can be seen that the technical solution described in the embodiment of the present application performs special calculations on the number of grooves, groove height, and groove angle of the connection area based on the powder focus height of the cladding head, thus solving the technical problem of limited thickness of the connection area. On the other hand, by processing according to the calculated gradient groove parameters of the present application, technical problems such as pore defects at the bottom of the connection area or easy deformation after forming can be effectively solved. Moreover, after obtaining different gradient groove parameters in the embodiment of the present application, the energy density values are calculated for different gradient grooves, so that different energy density values are applied to different gradient grooves during laser powder feeding, thereby effectively improving the connection strength of the connection area. Description of the Drawings

[0035] Figure 1 is a flowchart of the forming method for the connection area described in the embodiment of the present application;

[0036] Figure 2 is a structural schematic diagram where the powder focus height is greater than the maximum thickness of the connection area described in the embodiment of the present application;

[0037] Figure 3It is a schematic structural view of the powder coke height in the embodiment of the present application being less than the maximum thickness of the connection area;

[0038] wherein, R is the radius of the cladding head, and the β 1 is the first groove angle, the β 2 is the second groove angle, the β 3 is the third groove angle, θ is the powder feeding angle, H is the powder coke height, h is the maximum thickness of the connection area, and L is the width of the connection area. Specific Embodiments

[0039] It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0040] With the proposal of the overall aircraft design and the continuous increase in the size and load capacity of the aircraft, the manufacturing demand for large-sized complex components is becoming stronger and stronger. In order to manufacture large-sized complex parts, currently, the laser additive connection of split parts forming technology is used to solve problems such as limited forming size and large forming deformation of equipment.

[0041] The laser additive connection of split parts forming technology is a derivative of the laser melting deposition forming technology, which can realize controllable tissue morphology in the connection area and minimize the heat affected zone, and solve the problem of thickness limitation of connecting parts in traditional connection methods. However, the connection area obtained by printing with existing laser powder feeding 3D printing equipment cannot meet the application requirements.

[0042] Based on the above technical problems, as Figure 1 shown, the embodiment of the present application proposes: a connection area forming method, including the following steps:

[0043] Step S10, obtaining a first part process model.

[0044] In specific applications, the first part process model is a process digital model obtained by simplifying and thickening the part target model; that is, before obtaining the first part process model, it includes: obtaining a part target simulation model based on the application scenario; simplifying and thickening the part target simulation model to obtain the first part process model. In specific applications, the above operations can be performed using CATIA modeling software.

[0045] In specific applications, the simplifying and thickening the part target simulation model to obtain the first part process model includes: after deleting the small features of the part target simulation model, thickening each part surface by ≥5 mm to obtain the first part process model. Specifically, the small features include deleting fillets, small holes, etc., and filling and solidifying after deleting complex curved surfaces such as concave surfaces and chamfers.

[0046] Step S20: Split the first part process model to obtain a first split part and a second split part; there is a connection area between the first split part and the second split part; based on the connection area, obtain the maximum thickness of the connection area.

[0047] In specific applications, it is necessary to select a suitable area to split the first part process model to obtain a first split part and a second split part; and the connection area between the first split part and the second split part is generally symmetrically distributed. It should be noted that the first split part and the second split part are completed by laser powder feeding forming according to a mature process.

[0048] Step S30: Obtain a laser powder feeding device; based on the laser powder feeding device, obtain the powder focus height, powder feeding angle, and cladding head radius of the laser powder feeding device.

[0049] In specific applications, since the powder focus height, powder feeding angle, and cladding head radius of the 3D laser powder feeding device are fixed, before obtaining the gradient groove parameters, first measure the powder focus height and powder feeding angle of the actually used 3D laser powder feeding device to obtain the powder focus height, powder feeding angle, and cladding head radius of the laser powder feeding device, and calculate the gradient groove parameters based on the powder focus height and the powder feeding angle.

[0050] Step S40: Based on the powder focus height, the powder feeding angle, the cladding head radius, and the maximum thickness of the connection area, obtain gradient groove parameters; wherein, the gradient groove parameters include the number of gradient grooves, the gradient transition width, the gradient groove thickness, and the gradient groove angle.

[0051] In specific applications, step S40 of obtaining the gradient groove parameters based on the powder focus height, the powder feeding angle, the cladding head radius, and the maximum thickness of the connection area includes:

[0052] Step S41: Compare the powder focus height with the maximum thickness of the connection area to obtain a comparison result.

[0053] In specific applications, the powder focus height and the maximum thickness of the connection area may be in the following two situations. The first situation is that the powder focus height is greater than the maximum thickness of the connection area; the second situation is that the powder focus height is less than or equal to the maximum thickness of the connection area; therefore, here the powder focus height is compared with the maximum thickness of the connection area to obtain a comparison result, and based on the comparison result, the powder feeding angle, the cladding head radius, and the maximum thickness of the connection area, the gradient groove parameters are obtained, as described in step S42.

[0054] Step S42: Obtain gradient groove parameters based on the comparison result, the powder feeding angle, the radius of the cladding head, and the maximum thickness of the connection area.

[0055] In specific applications, the gradient groove parameters include the number of gradient grooves, the gradient transition width, the thickness of the gradient groove, and the gradient groove angle.

[0056] In the first case, as Figure 2 shown, that is, if the height of the powder coke is greater than the maximum thickness of the connection area, the number of gradient grooves is 2, the gradient transition width ≤ 5 mm, and the thickness of the first gradient groove does not exceed one - half of the maximum thickness of the connection area.

[0057] In the second case, as Figure 3 shown, that is, if the height of the powder coke is less than or equal to the maximum thickness of the connection area, then:

[0058] 1) The thickness of the first gradient groove for connection ≤ 10 mm, and the thickness of the remaining gradient grooves ≤ (height of powder coke - 5) mm.

[0059] 2) The number of gradient grooves is obtained through the following relational expression:

[0060] Number of gradient grooves > (h - h 1 ) / (H - 5) + 1

[0061] where h represents the maximum thickness of the connection area, H represents the height of the powder coke, and h 1 represents the thickness of the first gradient groove for connection.

[0062] 3) The groove angle β of the first gradient groove for connection is 50° - 70°; the groove angle β of other gradient grooves x is: powder feeding angle θ < β x ≤ 45°.

[0063] 4) The gradient transition width L of the first gradient groove for connection ≤ 5 mm, and the gradient transition width L of other gradient grooves x ≥ maximum radius R of the cladding head - (height of powder coke H - 5) * tanβ n-1 ; where β n-1 refers to the groove angle of the nth gradient groove.

[0064] Step S50: Based on the gradient groove parameters, perform gradient groove machining on the connection area of the first part process model to obtain a connection area simulation model; perform laser powder feeding machining based on the connection area model to obtain the target connection area.

[0065] In a specific application, the step S50 of performing gradient grooving on the connection area of the first part process model based on the gradient grooving parameters to obtain a connection area simulation model; and performing laser powder feeding processing based on the connection area model to obtain a target connection area, includes: performing gradient grooving on the connection area of the first part process model based on the gradient grooving parameters to obtain a connection area simulation model; obtaining the laser powder feeding energy density values of a plurality of gradient grooves based on the groove angles of the plurality of gradient grooves in the connection area simulation model; obtaining the forming process parameters of the plurality of gradient grooves based on the laser powder feeding energy density values; and performing laser powder feeding processing based on the forming process parameters to obtain a target connection area.

[0066] In a specific application, the energy density value is obtained through the following relational expression:

[0067] VED = P / (VHD)

[0068] Wherein, the VED represents the energy density value, the P represents the laser power, the V represents the scanning speed, the H represents the layer thickness, and the D represents the scanning pitch.

[0069] As can be seen from the above description, since existing laser powder feeding 3D printing devices usually use coaxial powder feeding as the main method, and the powder focus height of the laser coaxial powder feeding cladding head is generally fixed, within 20 - 80 mm for example. Therefore, when laser powder feeding is performed on a relatively thick connection area, the expected effect cannot be achieved. Specifically, the grooves of the connection area are mainly "V" - shaped and "X" - shaped. So when the groove angle of the connection area is too small, during the laser powder feeding process, the gas at the bottom of the groove cannot escape, resulting in gas being trapped in the connection area after solidification, forming pore defects, and further leading to poor connection performance of the formed connection area. If the groove angle of the connection area is too large, it will result in a larger connection area and an excessive deposition amount during laser powder feeding, and deformation is likely to occur in the connection area after solidification. Therefore, in view of the above - mentioned technical problems, the embodiment of the present application proposes a forming method for the connection area, that is: obtaining a first part process model; performing a split process on the first part process model to obtain a first split part and a second split part; where there is a connection area between the first split part and the second split part; based on the connection area, obtaining the maximum thickness of the connection area; obtaining a laser powder feeding device; based on the laser powder feeding device, obtaining the powder focus height, powder feeding angle, and cladding head radius of the laser powder feeding device; based on the powder focus height, powder feeding angle, cladding head radius, and the maximum thickness of the connection area, obtaining gradient groove parameters; where the gradient groove parameters include the number of gradient grooves, gradient transition width, gradient groove thickness, and gradient groove angle; based on the gradient groove parameters, performing gradient groove processing on the connection area of the first part process model to obtain a connection area simulation model; performing laser powder feeding processing based on the connection area model to obtain a target connection area. It can be seen that the technical solution of the embodiment of the present application performs special calculations on the number of grooves, groove height, and groove angle of the connection area based on the powder focus height of the cladding head, thereby solving the technical problem of limited thickness of the connection area. On the other hand, processing through the gradient groove parameters calculated in the present application can effectively solve technical problems such as the existence of pore defects at the bottom of the connection area or easy deformation after forming. Furthermore, after obtaining different gradient groove parameters in the embodiment of the present application, the energy density values are calculated for different gradient grooves, so that different energy density values are applied to different gradient grooves during laser powder feeding, thereby effectively improving the connection strength of the connection area.

[0070] The following specifically describes the forming method for the connection area of the present application with reference to specific embodiments:

[0071] Embodiment 1

[0072] In this embodiment, a frame - type part is selected for connection, and the specific implementation steps are as follows:

[0073] Step S1, obtaining a first part process model;

[0074] Step S2: Split the first part process model to obtain a first split part and a second split part; there is a connection area between the first split part and the second split part; based on the connection area, the maximum thickness h of the connection area is obtained as 60 mm;

[0075] Step S3: Obtain a laser powder feeding device; based on the laser powder feeding device, the powder focus height H of the laser powder feeding device is obtained as 25 mm, the powder feeding angle θ is 30°, and the radius R of the cladding head is 30 mm;

[0076] Step S4: Based on the powder focus height, the powder feeding angle, the radius of the cladding head, and the maximum thickness of the connection area, obtain gradient groove parameters; wherein, the gradient groove parameters include the number of gradient grooves, the gradient transition width, the gradient groove thickness, and the gradient groove angle; that is:

[0077] Since in the embodiment, the powder focus height H is less than the maximum thickness h of the connection area, it is the second case, that is, as Figure 3 shown; therefore:

[0078] 1). The thickness of the first gradient groove ≤ 10 mm, and the thickness of the remaining gradient grooves ≤ (H - 5) mm, that is, the thickness of the remaining gradient grooves ≤ 20 mm.

[0079] Therefore, set the thickness h of the first groove 1 to 10 mm, the thickness h of the second groove 2 to 20 mm, the thickness h of the third groove 3 to 20 mm, and the thickness h of the fourth groove 4 to 10 mm.

[0080] 2). The number of gradient grooves > (h - h 1 ) / (H - 5) + 1 = (60 - 10) / (25 - 5) + 1 = 3.5.

[0081] Therefore, set the number of gradient grooves to 4.

[0082] 3). The groove angle β of the first gradient groove is 50° - 70°, and is selected as 60°; the groove angle β of other gradient grooves x is: the powder feeding angle θ < β x ≤ 45°.

[0083] Therefore, set the first groove angle β 1 to 60°, the second groove angle β 2 to 40°, the third groove angle β 3 to 40°, and the fourth groove angle β 4Set to 35°.

[0084] 4), the gradient groove width L of the first gradient groove is ≤ 5 mm, and the gradient groove width L of other gradient grooves x ≥ the maximum radius R of the cladding head - (H - 5) * tanβ n-1 = 30 - (25 - 5) * tan40° = 13.2 mm.

[0085] Therefore, set the gradient groove width L of the first groove 1 to 5 mm, the gradient groove width L of the second groove 2 to 14 mm, the gradient groove width L of the third groove 3 to 14 mm, and the gradient groove width L of the fourth groove 4 to 14 mm.

[0086] Step S5: Based on the gradient groove parameters, perform gradient groove machining on the connection area of the first part process model, and perform fillet processing after machining. The fillet radius is 5 mm to obtain a connection area simulation model; based on the groove angles of several gradient grooves in the connection area simulation model, obtain the laser powder feeding energy density values of several gradient grooves; based on the laser powder feeding energy density values, obtain the forming process parameters of several gradient grooves; perform laser powder feeding processing based on the forming process parameters to obtain the target connection area.

[0087] In specific applications, the energy density value is obtained through the following relational expression:

[0088] VED = P / (VHD)

[0089] where, the VED represents the energy density value, the P represents the laser power, the V represents the scanning speed, the H represents the layer thickness, and the D represents the scanning spacing.

[0090] In this embodiment, the default process parameters of the laser powder feeding are: laser power P = 4 kW, scanning speed V = 16.7 mm / s, scanning spacing D = 3.5 mm, and layer thickness H = 1 mm. Since there are 3 groove angles, 3 energy densities are configured for the laser scanning profile parameters. In this embodiment, only the scanning speed is adjusted to adjust the energy density; the first groove is set with the default process parameters, and the profile energy density VED = P / (VHD) = 4000 / (16.7 * 3.5 * 1) = 68 J / mm 3 ; the profile energy density of the second and third grooves is 76 J / mm 3 , that is, the profile speed is reduced to 15 mm / s; the profile energy density of the fourth groove is 86 J / mm 3 , that is, the profile speed is reduced to 13.3 mm / s.

[0091] After setting the above process parameters, laser powder feeding connection is carried out. The finally obtained connection body has a small connection deformation and a high connection strength.

[0092] The above are only the preferred embodiments of the present application, and do not limit the patent scope of the present application. Any equivalent structure or equivalent process transformation made by using the content of the specification and drawings of the present application, or directly or indirectly applied to other related technical fields, shall be similarly included in the patent protection scope of the present application.

Claims

1. A method for forming a connection region, characterized in that, it includes the following steps: Obtain the first part process model; Perform a splitting process on the first part process model to obtain a first split part and a second split part; Wherein there is a connection region between the first split part and the second split part; Based on the connection region, obtain the maximum thickness of the connection region; Obtain a laser powder feeding device; Based on the laser powder feeding device, obtain the powder focus height, powder feeding angle, and cladding head radius of the laser powder feeding device; Based on the powder focus height, the powder feeding angle, the cladding head radius, and the maximum thickness of the connection region, obtain gradient groove parameters; wherein, the gradient groove parameters include the number of gradient grooves, the gradient transition width, the gradient groove thickness, and the gradient groove angle; Based on the gradient groove parameters, perform gradient groove machining on the connection region of the first part process model to obtain a connection region simulation model; based on the groove angles of several gradient grooves in the connection region simulation model, obtain the laser powder feeding energy density values of several gradient grooves; Based on the laser powder feeding energy density values, obtain the forming process parameters of several gradient grooves; perform laser powder feeding processing based on the forming process parameters to obtain the target connection region.

2. The connection region forming method according to claim 1, characterized in that, the obtaining of the gradient groove parameters based on the powder focus height, the powder feeding angle, the cladding head radius, and the maximum thickness of the connection region includes: Compare the powder focus height with the maximum thickness of the connection region to obtain a comparison result; Based on the comparison result, the powder feeding angle, the cladding head radius, and the maximum thickness of the connection region, obtain the gradient groove parameters.

3. The connection region forming method according to claim 2, characterized in that, if the powder focus height is greater than the maximum thickness of the connection region, the number of gradient grooves is 2, the gradient transition width ≤ 5 mm, and the thickness of the first gradient groove does not exceed one-half of the maximum thickness of the connection region.

4. The connection region forming method according to claim 2, characterized in that, if the powder focus height is less than or equal to the maximum thickness of the connection region, the thickness of the first gradient groove ≤ 10 mm, and the thickness of the remaining gradient grooves ≤ (powder focus height - 5) mm.

5. The connection region forming method according to claim 4, characterized in that, if the powder focus height is less than or equal to the maximum thickness of the connection region, the number of gradient grooves is obtained through the following relational expression: The number of gradient grooves > (h - h 1 ) / (H - 5) + 1 Among them, h represents the maximum thickness of the connection area, H represents the height of the pulverized coke, and the h 1 represents the thickness of the connection to the first gradient groove.

6. The connection region forming method according to claim 4, characterized in that, If the height of the pulverized coke is less than or equal to the maximum thickness of the connection area, the groove angle β of the first gradient groove for connection is 50° to 70°; the groove angle β of other gradient grooves x is: powder feeding angle θ < β x ≤ 45°.

7. The connection region forming method according to claim 4, characterized in that, If the height of the pulverized coke is less than or equal to the maximum thickness of the connection area, then the gradient transition width L of the first gradient groove for connection ≤ 5 mm, and the gradient transition width L of other gradient grooves x ≥ the maximum radius R of the cladding head - (the height H of the pulverized coke - 5) * tanβ n-1 ; where the β n-1 refers to the groove angle of the nth gradient groove.

8. The connection region forming method according to claim 1, characterized in that, before the obtaining of the first part process model, it includes: Based on the application scenario, obtain the part target simulation model; Perform a simplification process and a thickening process on the part target simulation model to obtain the first part process model.

9. The connection region forming method according to claim 8, characterized in that, Simplifying and thickening the target simulation model of the part to obtain a first part process model includes: After deleting the fine features of the target simulation model of the part, each part surface is thickened by ≥5 mm to obtain a first part process model.

10. The connection area forming method according to claim 1, characterized in that, the energy density value is obtained by the following relational expression: VED = P / (VHD) where VED represents the energy density value, P represents the laser power, V represents the scanning speed, H represents the layer thickness, and D represents the scanning pitch.

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