A method and system for calculating weld joint dilution

Abstract

The present disclosure belongs to the technical field of welding data processing, and provides a welding joint dilution rate calculation method and system, which acquires a metallographic photo of a welding joint, copies the contour of a weld and a fusion line on the metallographic photo, determines a groove size, draws the original shape of the joint at the corresponding position of the macro metallographic photo, calculates the cross-sectional area of the base metal melting into the welding joint and the cross-sectional area of the weld, and calculates the dilution rate of the welding joint. The present disclosure can directly measure the dilution rate, avoid many problems in indirect measurement, has good adaptability, is suitable for various groove types and various welding methods, and is helpful to promote the research and development of welding processes and the evaluation of joint quality.

Description

Technical Field

[0001] This disclosure belongs to the field of welding data processing technology, specifically relating to a method and system for calculating the dilution rate of welded joints. Background Technology

[0002] The statements in this section are merely background information relating to this disclosure and do not necessarily constitute prior art.

[0003] Dilution rate refers to the percentage of the weld cross-sectional area in which the base metal is melted into the weld. For example... Figure 1 As shown, when the compositions of materials A and B on both sides of the weld are different, the dilution rate caused by base material A is: D A =F A / (F A +F B +F1), the dilution rate caused by parent material B is: D B =F B / (F A +F B +F1).

[0004] When materials A and B on both sides of the weld have the same composition: the dilution rate caused by the base material is: D = (F A +F B ) / (F A +F B +F1).

[0005] In all fusion welded joints, a certain amount of base metal is melted by the welding heat source and mixed with the filler metal to form the weld. Because the composition of the filler metal differs from that of the base metal, the dilution rate caused by the base metal directly determines the composition of the weld, thus affecting the microstructure and properties of the weld metal.

[0006] It can be seen that dilution rate is an important concept in the field of welding technology, and it is particularly crucial for research areas such as dissimilar metal welding, weld overlay protection layer welding, new groove welding process testing, and the development of new welding processes. However, there is currently a lack of effective methods in the engineering and technical field for directly measuring dilution rate.

[0007] According to the inventor, there are currently two commonly used methods to indirectly determine the dilution rate of welded joints. The first is the elemental calculation method, which calculates the dilution rate by measuring the content of certain elements in the weld microstructure based on the differences in element content between the base metal and the filler metal.

[0008] This method has the following problems: First, it requires sophisticated equipment, such as scanning electron microscopes, to determine the elemental content in minute areas of the weld. Second, the elemental distribution is uneven across different areas of the weld, necessitating the selection of numerous micro-regions for measurement, which further increases cost and time. Third, both the base metal and filler metal experience some degree of element loss during welding, significantly reducing the measurement accuracy. Fourth, the method requires etching the sample to determine the weld area before subsequent elemental measurements can be performed; however, the etching process interferes with elemental determination, further affecting the method's accuracy.

[0009] For these reasons, elemental determination is not only less accurate (with an error of nearly 20%), but also more expensive, which is why this method has not been widely used.

[0010] The second method is the model calculation method. This method simplifies the weld shape and uses different algorithms such as genetic neural networks, Elman grid algorithm, response surface methodology, and statistical analysis to establish a model for calculating the dilution rate through process parameters such as welding current and welding speed. The dilution rate is calculated through a mathematical model.

[0011] However, this model has many shortcomings. For example, it does not consider the effect of filler metal and it is difficult to establish a direct relationship with the dilution rate. Using this model to study the relationship between heat input and dilution rate can easily lead to contradictory conclusions. In addition, the model collects basic data through simple welding tests and also verifies the model through welding tests. However, the welding process differs significantly from conventional welding processes. Therefore, this model is not applicable to most welding processes, nor to common bevel types, and it cannot be adjusted according to actual conditions such as misalignment and welding deformation.

[0012] For these reasons, the model-based calculation method has poor adaptability and low calculation accuracy, and therefore has not been widely used.

[0013] In summary, given the numerous shortcomings of the two calculation methods mentioned above, it is necessary to change our approach and develop a method for directly measuring the dilution rate of welded joints based on the definition of dilution rate. Summary of the Invention

[0014] To address the aforementioned problems, this disclosure proposes a method and system for calculating the dilution rate of welded joints. This disclosure solves the problems of difficulty and inaccuracy in calculating the dilution rate of welded joints, and can directly measure the dilution rate, avoiding many problems associated with indirect measurement. It has good applicability and can be adjusted according to the welding conditions.

[0015] According to some embodiments, the present disclosure adopts the following technical solutions:

[0016] A method for calculating the dilution rate of a welded joint includes the following steps:

[0017] Obtain metallographic images of the welded joint;

[0018] Copy the outline of the weld and its fusion line from a metallographic photograph;

[0019] Determine the bevel size and draw the original shape of the joint on the corresponding position in the macroscopic metallographic photograph;

[0020] Calculate the cross-sectional area of ​​the base metal melted into the weld joint and the cross-sectional area of ​​the weld, and calculate the dilution rate of the weld joint.

[0021] As an alternative implementation, the metallographic photograph is imported into computer-aided design software before tracing the outline of the weld and its fusion line on the metallographic photograph.

[0022] As a further implementation method, the magnification per unit length is determined, the size of the macroscopic metallographic photograph is adjusted, and after the macroscopic metallographic photograph is adjusted to the set scale, the outline of the weld and its fusion line is traced.

[0023] As an alternative implementation, the bevel size is determined, the original shape of the joint is plotted on the corresponding position in the macroscopic metallographic photograph, and the weld is divided into several closed areas.

[0024] As an alternative implementation, the cross-sectional area of ​​each closed region is calculated based on the weld seam, and then the cross-sectional area of ​​the base material fused into the weld joint and the cross-sectional area of ​​the weld are calculated.

[0025] As a further implementation, the principle for dividing the closed areas is that there is no overlap between the areas, and the sum of the closed areas is the outline area of ​​the entire joint shape.

[0026] The area whose cross-sectional area does not involve the fusion of the base material into the weld joint is treated as a separate area.

[0027] As an alternative implementation, if the joint exhibits angular deformation greater than a set value, the deformation angle of the joint is measured, and the original shape of the joint is rotated around a reference point in the direction of deformation based on this deformation angle.

[0028] A system for calculating the dilution rate of a welded joint, comprising:

[0029] The image receiving module is configured to acquire metallographic images of the welded joint;

[0030] The contour drawing module is configured to trace the contours of welds and their fusion lines on metallographic photographs.

[0031] The original shape drawing module is configured to determine the bevel size and draw the original shape of the joint on the corresponding position in the macroscopic metallographic photograph;

[0032] The calculation module is configured to calculate the cross-sectional area of ​​the base metal melted into the weld joint and the cross-sectional area of ​​the weld, and to calculate the dilution rate of the weld joint.

[0033] A computer-readable storage medium storing a plurality of instructions adapted for loading by a processor of a terminal device and executing steps in the method.

[0034] A terminal device includes a processor and a computer-readable storage medium, the processor being configured to implement instructions; the computer-readable storage medium being configured to store a plurality of instructions adapted to be loaded by the processor and executed in accordance with the steps of the method described therein.

[0035] Compared with the prior art, the beneficial effects of this disclosure are as follows:

[0036] This disclosure enables direct measurement of dilution rate, avoiding many problems associated with indirect measurement; it also has good adaptability, applicable to various bevel types and welding methods, and helps to promote welding process development and joint quality assessment.

[0037] This invention is simple to operate, has high calculation accuracy, and is flexible in operation. It can be adjusted according to actual conditions such as misalignment and welding deformation.

[0038] This disclosure streamlines, standardizes, and formalizes the dilution rate calculation process, effectively addressing issues such as the difficulty and inaccuracy in calculating the dilution rate of welded joints.

[0039] To make the above-mentioned objects, features and advantages of this disclosure more apparent and understandable, preferred embodiments are described below in detail with reference to the accompanying drawings. Attached Figure Description

[0040] The accompanying drawings, which form part of this disclosure, are used to provide a further understanding of this disclosure. The illustrative embodiments of this disclosure and their descriptions are used to explain this disclosure and do not constitute an undue limitation of this disclosure.

[0041] Figure 1 This is a schematic diagram illustrating the principle of dilution rate calculation;

[0042] Figure 2 This is a schematic diagram of the macroscopic metallographic photograph import CAD operation interface in Example 1;

[0043] Figure 3 This is a schematic diagram of the outline of the weld and its fusion line in Example 1;

[0044] Figure 4 This is a schematic diagram of the original shape of the connector in Example 1 drawn on a macroscopic metallographic photograph;

[0045] Figure 5This is a schematic diagram illustrating the calculation of the area of ​​each enclosed region in Example 1;

[0046] Figure 6 This is a schematic diagram of the macroscopic metallographic photograph import CAD operation interface in Example 2;

[0047] Figure 7 This is a schematic diagram of the outline of the weld and its fusion line in Example 2;

[0048] Figure 8 This is a schematic diagram of the original shape of the joint in Example 2 drawn on a macroscopic metallographic photograph;

[0049] Figure 9 This is a schematic diagram illustrating the calculation of the area of ​​each enclosed region in Example 2;

[0050] Figure 10 This is a schematic diagram of the macroscopic metallographic photograph import CAD operation interface in Example 3;

[0051] Figure 11 This is a schematic diagram of the outline of the weld and its fusion line in Example 3;

[0052] Figure 12 This is a schematic diagram of the original shape of the connector in Example 3 drawn on a macroscopic metallographic photograph;

[0053] Figure 13 This is a schematic diagram of the macroscopic metallographic photograph import CAD operation interface in Example 4;

[0054] Figure 14 This is a schematic diagram of the outline of the weld and its fusion line in Example 4;

[0055] Figure 15 This is a schematic diagram of the original shape of the joint in Example 4 drawn on a macroscopic metallographic photograph;

[0056] Figure 16 This is a flowchart of the process disclosed herein. Detailed implementation method:

[0057] The present disclosure will be further described below with reference to the accompanying drawings and embodiments.

[0058] It should be noted that the following detailed descriptions are illustrative and intended to provide further explanation of this disclosure. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure pertains.

[0059] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this disclosure. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms “comprising” and / or “including” are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0060] In this disclosure, terms such as "upper," "lower," "left," "right," "front," "back," "vertical," "horizontal," "side," and "bottom" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are merely relational terms determined for the convenience of describing the structural relationship of the various components or elements in this disclosure, and do not specifically refer to any component or element in this disclosure, nor should they be construed as limiting this disclosure.

[0061] In this disclosure, terms such as "fixed connection," "connected," and "linked" should be interpreted broadly, indicating a fixed connection, an integral connection, or a detachable connection; a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can determine the specific meaning of these terms in this disclosure based on the specific circumstances, and they should not be construed as limitations on this disclosure.

[0062] This disclosure provides a method for calculating the dilution rate of welded joints, such as... Figure 16 As shown, it includes:

[0063] Step 1: Obtain macroscopic metallographic images of the welded joint through metallographic testing.

[0064] Step 2: Import the macroscopic metallographic photographs into the interface of the computer-aided software (CAD is used as an example).

[0065] Step 3: Trace the outline of the weld and its fusion line.

[0066] Step 4: Determine the bevel size according to the welding process specification, draw the original shape of the joint (before welding) on ​​the corresponding position of the macroscopic metallographic photograph, and divide the area.

[0067] Step 5: Calculate the area of ​​each region of the welded joint in sequence, and calculate the cross-sectional area of ​​the base metal melted into it and the cross-sectional area of ​​the weld.

[0068] Step 6: Calculate the percentage of the cross-sectional area of ​​the base metal melted into the weld cross-sectional area to obtain the weld joint dilution rate.

[0069] The following provides a detailed description of different embodiments.

[0070] Example 1

[0071] The calculation process for the dilution rate of aluminum alloy laser filler wire welded fillet joints includes:

[0072] (1) Obtain macroscopic metallographic images of aluminum alloy laser filler wire welded joints by metallographic testing;

[0073] (2) Check the macroscopic metallographic photographs to determine whether the weld fusion line is clear and whether the scale is complete and accurate;

[0074] (3) Import the macroscopic metallographic images into the CAD operating interface, such as... Figure 2 As shown;

[0075] (4) Measure the size of the scale in the macro metallographic photograph in the CAD operation interface, determine the magnification per unit length, and reduce the macro metallographic photograph to the normal scale accordingly.

[0076] (5) Use the "spline curve" function in CAD software to trace the outline of the weld and its fusion line, such as... Figure 3 As shown;

[0077] (6) Based on the welding procedure specification, it was determined that the joint had no beveling and no gap. Accordingly, the original shape of the joint (before welding) was plotted on the corresponding position in the macroscopic metallographic photograph, and the weld was divided into F... A District, F B District, F1 District, such as Figure 4 As shown;

[0078] (7) F A The lines around the area merge to form a closed shape. Select this closed shape, right-click, and choose Properties - Geometry - Area to obtain F. A Area data of the district, such as Figure 5 As shown. F is obtained in the same way. B Area data for Zone F1 and Zone F. A District, F B The areas of Zone 1 and Zone 2 are 4.05 mm. 2 2.15mm 2 1.30mm 2 ;

[0079] (8) Apply the formula to calculate the dilution rate, and obtain D = (F A +F B ) / (F A +F B +F1)=(4.05+2.15) / (4.05+2.15+1.30)=82.67%.

[0080] Example 2

[0081] The calculation process for the dilution rate of aluminum alloy MIG welded butt joints includes:

[0082] (1) Obtain macroscopic metallographic images of aluminum alloy MIG welded joints by metallographic testing;

[0083] (2) Check the macroscopic metallographic photographs to determine whether the weld fusion line is clear and whether the scale is complete and accurate;

[0084] (3) Import the macroscopic metallographic images into the CAD operating interface, such as... Figure 6 As shown;

[0085] (4) Measure the size of the scale in the macro metallographic photograph in the CAD operation interface, determine the magnification per unit length, and reduce the macro metallographic photograph to the normal scale accordingly.

[0086] (5) Use the "spline curve" function in CAD software to trace the outline of the weld and its fusion line, such as... Figure 7 As shown;

[0087] (6) According to the welding procedure specification, the bevel dimensions of the joint are determined to be a double-sided 70° bevel, a 3mm gap, and a 0mm blunt edge. Based on this, the original shape of the joint (before welding) is drawn on the corresponding position in the macroscopic metallographic photograph, and the weld is divided into F... A District, F B District, F1 District, such as Figure 8 As shown;

[0088] (7) F A The lines around the area merge to form a closed shape. Select this closed shape, right-click, and choose Properties - Geometry - Area to obtain F. A Area data of the district, such as Figure 9 As shown. F is obtained in the same way. B Area data for Zone F1 and Zone F. A District, F B The areas of Zone 1 and Zone 2 are 2.83 mm. 2 2.13mm 2 28.14mm 2 ;

[0089] (8) Apply the formula to calculate the dilution rate, and obtain D = (F A +F B ) / (F A +F B +F1)=(2.83+2.13) / (2.83+2.13+28.14)=14.98%.

[0090] Example 3

[0091] Calculation process for dilution rate of aluminum alloy laser-MIG hybrid welding butt joint:

[0092] An example of adjustments made based on the melting condition of the base material.

[0093] (1) Obtain macroscopic metallographic images of the laser-MIG composite welded joint of aluminum alloy by metallographic testing;

[0094] (2) Check the macroscopic metallographic photographs to determine whether the weld fusion line is clear and whether the scale is complete and accurate;

[0095] (3) Import the macroscopic metallographic images into the CAD operating interface, such as... Figure 10 As shown;

[0096] (4) Measure the size of the scale in the macro metallographic photograph in the CAD operation interface, determine the magnification per unit length, and reduce the macro metallographic photograph to the normal scale accordingly.

[0097] (5) Use the "spline curve" function in CAD software to trace the outline of the weld and its fusion line, such as... Figure 11 As shown;

[0098] (6) According to the welding procedure specification, the bevel dimensions of the joint are determined to be a double-sided 20° bevel, 0mm gap, and 2mm blunt edge. Based on this, the original shape of the joint (before welding) is drawn on the corresponding position in the macroscopic metallographic photograph, and the weld and its surrounding area are divided into F... A District, F B Area, F1 area, F2 area, F C District, F D District, such as Figure 12 As shown. Where F C District, F D The area is the depression left by the welding heat source melting the base material. C District, F D The original base metal structure of the area has been fused into the weld, so these two areas also need to be measured according to the cross-sectional area of ​​the base metal fused into it;

[0099] (7) F A The lines around the area merge to form a closed shape. Select this closed shape, right-click, and choose Properties - Geometry - Area to obtain F. A Area data of the region. F is obtained using the same method. B Area, F1 area, F2 area, F C District, F D Area data for the district. F A District, F B Area, F1 area, F2 area, F C District, F D The area of ​​the region is 30.99 mm. 2 37.37mm 2 24.55mm 215.11mm 2 0.79mm 2 0.29mm 2 ;

[0100] (8) Apply the formula to calculate the dilution rate, and obtain D = (F A +F B +F C +F D ) / (F A +F B +F C +F D +F1+F2)=(30.99+37.37+0.79+0.29) /

[0101] (30.99+37.37+0.79+0.29+24.55+15.11)=63.65%.

[0102] Example 4

[0103] Dilution rate calculation for aluminum alloy MIG welding T-shaped butt joints (J-shaped bevel):

[0104] This embodiment is an example of adjustment based on the angular deformation of the welded joint.

[0105] (1) Obtain macroscopic metallographic images of aluminum alloy MIG welded joints by metallographic testing;

[0106] (2) Check the macroscopic metallographic photographs to determine whether the weld fusion line is clear and whether the scale is complete and accurate;

[0107] (3) Import the macroscopic metallographic images into the CAD operating interface, such as... Figure 13 As shown;

[0108] (4) Measure the size of the scale in the macro metallographic photograph in the CAD operation interface, determine the magnification per unit length, and reduce the macro metallographic photograph to the normal scale accordingly.

[0109] (5) Use the "spline curve" function in CAD software to trace the outline of the weld and its fusion line, such as... Figure 14 As shown;

[0110] (6) According to the welding procedure specification, the bevel of the joint is determined to be a J-shaped bevel. The dimensions of the J-shaped bevel are 5mm rounded corner, 25° bevel on one side, 2mm gap, 2mm blunt edge, and 2mm plateau. Based on this, the original shape of the joint (before welding) is drawn on the corresponding position of the macroscopic metallographic photograph. Because the T-shaped joint exhibits significant angular deformation, to ensure the accuracy of the calculation, the deformation angle of the T-shaped joint is measured in the CAD operation interface. The measured angular deformation is 5.1°. Based on this, the original shape of the joint (before welding) is rotated 5.1° around the reference point in the direction of deformation. After the original shape of the joint (before welding) is adjusted, the weld can be divided into F... A1 District, F A2 District, F B District, F C District, F1 District, such as Figure 15 As shown;

[0111] (7) F A1 The lines around the area merge to form a closed shape. Select this closed shape, right-click, and choose Properties - Geometry - Area to obtain F. A1 Area data of the region. F is obtained using the same method. A2 District, F B District, F C Area data for Zone F1 and Zone F. A1 District, F A2 District, F B District, F C The areas of Zone 1 and Zone 2 are 6.92 mm. 2 2.24mm 2 8.07mm 2 3.82mm 2 146.04mm 2 ;

[0112] (8) Apply the formula to calculate the dilution rate, and obtain D = (F A1 +F A2 +F B +F C ) / (F A1 +F A2 +F B +F C +F1)=(6.92+2.24+8.07+3.82) / (6.92+2.24+8.07+3.82+146.04)=12.60%.

[0113] The above description is merely a preferred embodiment of this disclosure and is not intended to limit this disclosure. Various modifications and variations can be made to this disclosure by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this disclosure should be included within the scope of protection of this disclosure.

[0114] While the specific embodiments of this disclosure have been described above in conjunction with the accompanying drawings, this is not intended to limit the scope of protection of this disclosure. Those skilled in the art should understand that various modifications or variations that can be made by those skilled in the art without creative effort based on the technical solutions of this disclosure are still within the scope of protection of this disclosure.

Claims

1. A method for calculating the dilution rate of a welded joint, characterized in that, Includes the following steps: Obtain metallographic images of the welded joint; Copy the outline of the weld and its fusion line from a metallographic photograph; Determine the bevel size and draw the original shape of the joint on the corresponding position in the macroscopic metallographic photograph; Calculate the cross-sectional area of ​​the base metal melted into the weld joint and the cross-sectional area of ​​the weld, and calculate the dilution rate of the weld joint; Determine the bevel size, draw the original shape of the joint on the corresponding position of the macroscopic metallographic photograph, and divide the weld into several closed areas; Based on the several closed regions divided by the weld, calculate the cross-sectional area of ​​each closed region, and then calculate the cross-sectional area of ​​the base material fused into the weld joint and the cross-sectional area of ​​the weld.

2. The method for calculating the dilution rate of a welded joint as described in claim 1, characterized in that, Before tracing the outline of the weld and fusion line on the metallographic photograph, import the metallographic photograph into computer-aided design software.

3. The method for calculating the dilution rate of a welded joint as described in claim 2, characterized in that, Determine the magnification per unit length, adjust the size of the macroscopic metallographic photograph, and after adjusting the macroscopic metallographic photograph to the set scale, trace the outline of the weld and its fusion line.

4. The method for calculating the dilution rate of a welded joint as described in claim 1, characterized in that, The principle for dividing the closed areas is that there is no overlap between the areas, and the sum of the closed areas is the outline area of ​​the entire joint shape. The area whose cross-sectional area does not involve the fusion of the base material into the weld joint is treated as a separate area.

5. The method for calculating the dilution rate of a welded joint as described in claim 1, characterized in that, If the joint exhibits angular deformation greater than the set value, measure the deformation angle of the joint, and based on this deformation angle, rotate the original shape of the joint around the reference point in the direction of deformation.

6. A system for calculating the dilution rate of a welded joint, characterized in that, include: The image receiving module is configured to acquire metallographic images of the welded joint; The contour drawing module is configured to trace the contours of welds and their fusion lines on metallographic photographs. The original shape drawing module is configured to determine the bevel size and draw the original shape of the joint on the corresponding position in the macroscopic metallographic photograph; The calculation module is configured to calculate the cross-sectional area of ​​the base metal melted into the weld joint and the cross-sectional area of ​​the weld, and to calculate the dilution rate of the weld joint. Determine the bevel size, draw the original shape of the joint on the corresponding position of the macroscopic metallographic photograph, and divide the weld into several closed areas; Based on the several closed regions divided by the weld, calculate the cross-sectional area of ​​each closed region, and then calculate the cross-sectional area of ​​the base material fused into the weld joint and the cross-sectional area of ​​the weld.

7. A computer-readable storage medium, characterized in that, It stores multiple instructions adapted for loading by the processor of a terminal device and executing the steps of the method according to any one of claims 1-5.

8. A terminal device, characterized in that, It includes a processor and a computer-readable storage medium, the processor being used to implement various instructions; the computer-readable storage medium being used to store a plurality of instructions adapted to be loaded by the processor and executed in the steps of the method of any one of claims 1-5.

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