Method for predicting composition of submerged arc weld metal and use thereof

Abstract

This invention relates to the field of welding technology, and more specifically, to a method for predicting the composition of submerged arc welding weld metal and its application. The method involves obtaining the mass percentage M of the element to be predicted in the molten droplet. droplet ; Calculate Δ droplet Δ droplet =(M droplet -M el )×(1-d); Calculate Δ WM‑O Δ WM‑Mn and Δ WM‑Si Δ WM‑O =0.61874×Δ droplet +0.05013, Δ WM‑Mn =1.0959×Δ droplet -0.11298, Δ WM‑Si =0.706×Δ droplet -0.01031; Calculate M N M N =M BM ×d+M el ×(1-d); Calculate the predicted mass percentage content P of the submerged arc weld metal elements. WM =Δ WM +M N This method provides a high degree of accuracy in predicting the composition of the weld metal.

Description

Technical Field

[0001] This invention relates to the field of welding technology, and more specifically, to a method for predicting the composition of submerged arc welding weld metal and its application. Background Technology

[0002] Submerged arc welding (SAW) is a welding method that uses an electric arc between a molten welding wire and a metal workpiece to heat and melt the metal. Unlike other arc welding methods, the arc in SAW burns under a protective layer composed of molten slag (molten flux) and granular flux. The slag not only protects the molten pool from harmful gases such as oxygen and nitrogen in the air, but also prevents alloy burn-off, purifies the molten pool (absorbing inclusions, dephosphorizing and desulfurizing), stabilizes the arc, and makes the welding process stable. The protective and purifying effects of the slag contribute to the production of defect-free weld metal. Furthermore, due to the intense chemical reactions between the slag, the molten pool, and the arc plasma, the flux has a significant regulatory effect on the composition of the weld metal, thereby influencing its microstructure and mechanical properties.

[0003] The composition of submerged arc weld metal is significantly regulated by the flux components. Specifically, the oxygen (O) content in the weld metal should be controlled between 0.02 wt.% and 0.05 wt.%. Excessive O content reduces the hardness and low-temperature impact toughness of the weld metal and increases the likelihood of porosity, negatively impacting mechanical properties. Conversely, insufficient O content prevents the formation of acicular ferrite within the weld, resulting in lower low-temperature impact toughness.

[0004] Si and Mn are fundamental alloying elements in weld metal. Studies have shown that the Si content is typically controlled below 0.6 wt.%, as excessively high Si content leads to a decrease in the low-temperature impact toughness and ductility of the weld metal. When the Mn content is in the range of 0.6 wt.% to 1.8 wt.%, increasing the Mn content promotes the formation of acicular ferrite in the weld metal and reduces the volume fraction of polygonal ferrite and side-lamellar ferrite. Therefore, controlling the composition of the weld metal is crucial for strengthening the microstructure and properties of welded joints.

[0005] In the actual production and research and development of submerged arc welding joints, the control of weld microstructure and properties is often achieved through orthogonal experiments. This requires the compositional analysis of a large number of weld microstructures obtained from the experiments, which consumes a great deal of economic and time costs.

[0006] In existing technologies, methods for predicting weld metal composition are mainly based on thermodynamic calculations using welding and steelmaking databases. However, data specifically for submerged arc welding (SAW) is generally lacking, and these methods cannot fully adapt to the characteristics of SAW, resulting in significant discrepancies between the predicted and actual chemical composition of SAW weld metal.

[0007] Therefore, it is of great significance to provide a method for predicting the composition of submerged arc welding weld metal.

[0008] In view of this, the present invention is hereby proposed. Summary of the Invention

[0009] The primary objective of this invention is to provide a method for predicting the composition of submerged arc welding weld metal. By collecting molten droplets and obtaining reliable basic data for weld composition prediction, the method improves the accuracy and convenience of weld composition prediction, effectively reduces the cost of weld metal composition testing, avoids a large number of actual welding experiments and corresponding composition testing work, and improves production and R&D efficiency.

[0010] The second objective of this invention is to provide a method for predicting the composition of submerged arc welding weld metal and its application in the preparation of flux and weldment.

[0011] In order to achieve the above-mentioned objectives of the present invention, the following technical solution is adopted:

[0012] This invention first provides a method for predicting the composition of submerged arc welding weld metal, comprising the following steps:

[0013] A molten droplet is obtained, and its chemical composition is analyzed to obtain the mass percentage M of the element to be predicted in the molten droplet. droplet The flux used to form the droplets comprises the following components by mass percentage: CaO 10wt.%–55wt.%, SiO2 40wt.% and MnO 5wt.%–50wt.%; the element to be predicted includes at least one of O, Mn and Si.

[0014] Calculate the degree Δ of the predicted element in the flux transitioning into the molten droplet. droplet Δ droplet =(M droplet -M el )×(1-d), where M el d represents the mass percentage of the element to be predicted in the welding wire, and d is the dilution ratio.

[0015] Calculate the degree Δ of the predicted element in the flux transitioning into the weld metal. WM Δ WM Including Δ WM-O Δ WM-Mn and Δ WM-Si , where Δ WM-O =0.61874×Δ droplet +0.05013, Δ WM-Mn =1.0959×Δ droplet -0.11298, Δ WM-Si =0.706×Δdroplet -0.01031;

[0016] Calculate the nominal composition M of the weld metal N M N =M BM ×d+M el ×(1-d), where M BM The mass percentage of the element to be predicted in the parent material;

[0017] Calculate the predicted mass percentage of elemental composition P in the submerged arc weld metal. WM P WM =Δ WM +M N ;

[0018] Wherein, the Δ is calculated droplet The M N and the P WM During the process, the corresponding mass percentage of the element to be predicted is substituted into the equation.

[0019] Furthermore, a droplet collection device is used to collect the cooled droplets.

[0020] Furthermore, the droplet collection device includes a cooling component and a metal conductive component.

[0021] Furthermore, d = 0.5 to 0.7.

[0022] Further, d = diluted base metal cross-sectional area / weld metal cross-sectional area.

[0023] Furthermore, the welding wire includes at least one of CHW-S80 welding wire, H10Mn2 welding wire, H10Mn2q welding wire, and H08Mn2MoA welding wire.

[0024] Furthermore, the base material includes steel.

[0025] Furthermore, the steel includes at least one of EH36 steel, EH420 steel, EH460 steel, and EH550 steel.

[0026] Furthermore, the error of the method for predicting the composition of submerged arc weld metal is ≤0.02wt.%.

[0027] The present invention also provides the application of the method for predicting the composition of submerged arc welding weld metal in the preparation of flux and weldment.

[0028] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0029] (1) The method for predicting the composition of submerged arc weld metal provided by the present invention has a high accuracy rate in predicting the chemical composition of submerged arc weld metal.

[0030] (2) The method for predicting the composition of submerged arc welding weld metal provided by the present invention is simple, convenient and efficient, which can improve production and R&D efficiency and reduce costs. Attached Figure Description

[0031] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0032] Figure 1 This is a three-dimensional structural schematic diagram of the droplet collection device provided by the present invention;

[0033] Figure 2 This is a top view of the molten droplet obtained in Example 1 of the present invention. Detailed Implementation

[0034] The technical solution of the present invention will be clearly and completely described below with reference to the accompanying drawings and specific embodiments. However, those skilled in the art will understand that the embodiments described below are some embodiments of the present invention, but not all embodiments, and are only used to illustrate the present invention, and should not be regarded as limiting the scope of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention. Where specific conditions are not specified in the embodiments, conventional conditions or conditions recommended by the manufacturer shall be followed. Where the manufacturers of reagents or instruments are not specified, they are all conventional products that can be purchased commercially.

[0035] Unless otherwise specified, in this invention, terms such as "first aspect," "second aspect," "third aspect," and "fourth aspect" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or quantity, nor should they be construed as implicitly indicating the importance or quantity of the indicated technical features. Moreover, terms such as "first," "second," "third," and "fourth" serve only as a non-exhaustive enumeration and should be understood not to constitute a closed limitation on quantity.

[0036] Unless otherwise specified, the terms "comprising" and "including" as used in this invention can be open-ended or closed-ended. For example, "comprising" and "including" can mean that other components not listed may also be included, or that only the listed components may be included.

[0037] Unless otherwise specified, in this invention, "one or more" or "at least one" refers to any one, any two, or any two or more of the listed items. "Several" refers to any two or more.

[0038] In a first aspect, the present invention provides a method for predicting the composition of submerged arc welding weld metal, comprising the following steps:

[0039] (1) Obtain a molten droplet and perform chemical composition analysis on the molten droplet to obtain the mass percentage M of the element to be predicted in the molten droplet. droplet The element to be predicted includes at least one of O, Mn, and Si.

[0040] Understandably, the analysis of the chemical composition of the molten droplets selects elements from the oxides contained in the flux, including but not limited to O, Mn, and Si. Other elements are determined by the combination of the welding wire and the base material, exhibiting no special changes, and therefore do not require detection; their calculation method is the same as that for the nominal composition.

[0041] In some specific implementations, chemical composition analysis is performed on the molten droplet to obtain the mass percentage M of O element in the molten droplet. droplet-O The mass percentage of Mn element in the molten droplet M droplet-Mn and the mass percentage of Si in the molten droplet M droplet-Si .

[0042] The flux used to form the droplets comprises the following components in mass percentage: CaO 10 wt.% to 55 wt.%, SiO2 40 wt.%, and MnO 5 wt.% to 50 wt.%.

[0043] The CaO, by mass percentage, includes, but is not limited to, any one of 10 wt.%, 20 wt.%, 30 wt.%, 40 wt.%, 50 wt.%, and 55 wt.%, or any range between any two; the MnO, by mass percentage, includes, but is not limited to, any one of 5 wt.%, 10 wt.%, 20 wt.%, 30 wt.%, 40 wt.%, and 50 wt.%, or any range between any two.

[0044] (2) Calculate the degree of transition Δ of the element to be predicted in the flux into the molten droplet. droplet , where Δ droplet =(M droplet -M el )×(1-d), where M el d represents the mass percentage of the element to be predicted in the welding wire, and d is the dilution ratio.

[0045] In some specific implementations, chemical composition analysis is performed on the welding wire to obtain the mass percentage M of the oxygen element in the welding wire. el-O The mass percentage of Mn element in the welding wire el-Mn The mass percentage of Si element in the welding wire, M el-Si .

[0046] It is understandable that calculating Δ droplet When substituting these values, the mass percentages of O, Mn, and Si elements are respectively used. For example, Δ droplet-O =(M droplet-O -M el-O )×(1-d);

[0047] Δ droplet-Mn =(M droplet-Mn -M el-Mn )×(1-d);

[0048] Δ droplet-Si =(M droplet-Si -M el-Si )×(1-d).

[0049] (3) Calculate the degree Δ of the predicted element in the flux transitioning into the weld metal. WM .

[0050] It is understandable that the degree of transition Δ of the predicted element in the flux into the weld metal is... WM The basic model formula is Δ WM =a(z)×Δ droplet +b(y), where a(z) and b(y) are functions representing the relationship between the molten droplet and the composition of the weld metal, respectively, and the functions are affected by the composition of the flux.

[0051] In submerged arc welding, elemental transition mainly occurs in the droplet stage. After the droplet falls into the molten pool, it is diluted, and then the next stage of elemental transition occurs at the slag-metal interface. Therefore, there is a certain proportional relationship between the droplet composition and the weld metal composition.

[0052] For the flux composition range defined in this invention, Δ WM Including Δ WM-O Δ WM-Mn and Δ WM-Si Their respective prediction models are:

[0053] Δ WM-O =0.61874×Δ droplet-O +0.05013;

[0054] Δ WM-Mn =1.0959×Δ droplet-Mn -0.11298;

[0055] Δ WM-Si =0.706×Δ droplet-Si -0.01031.

[0056] (4) Calculate the nominal composition M of the weld metal. N M N =M BM ×d+M el ×(1-d), where M BM This represents the mass percentage of the element to be predicted in the parent material.

[0057] In some specific implementations, chemical composition analysis is performed on the parent material to obtain the mass percentage M of O element in the parent material. BM-O The mass percentage of Mn element in the parent material BM-Mn The mass percentage of Si element in the parent material M BM-Si .

[0058] It is understandable that calculating M N When substituting these values, substitute the mass percentages of O, Mn, and Si elements respectively. For example, M... N-O =M BM-O ×d+M el-O ×(1-d);

[0059] M N-Mn =M BM-Mn ×d+M el-Mn ×(1-d);

[0060] M N-Si =M BM-Si ×d+M el-Si ×(1-d).

[0061] (5) Calculate the predicted mass percentage of metal elements in the submerged arc weld, P. WM P WM =Δ WM +M N .

[0062] It is understandable that calculating P WM When substituting these values, substitute the mass percentages of O, Mn, and Si elements respectively. For example, P WM-O =Δ WM-O +M N-O ;

[0063] P WM-Mn =Δ WM-Mn +M N-Mn ;

[0064] P WM-Si =Δ WM-Si +MN-Si .

[0065] This allows us to obtain the predicted mass percentage content of O, Mn, and Si elements in the submerged arc weld metal.

[0066] The method for predicting the chemical composition of submerged arc weld metal provided by this invention collects molten droplets and obtains the mass percentage content data of the element to be predicted in the molten droplets, and substitutes the data into the weld metal composition prediction model for calculation. The accuracy of predicting the chemical composition of submerged arc weld metal is high.

[0067] Furthermore, the method for predicting the chemical composition of submerged arc welding weld metal provided by this invention is simple and convenient, which can effectively reduce the detection cost of weld metal composition, avoid a large number of actual welding experiments and corresponding composition detection work, and improve production and R&D efficiency.

[0068] In some specific implementations, a droplet collection device is used to collect the cooled droplets.

[0069] Among these methods, using a droplet collection device to collect droplets, combined with composition prediction methods, can further improve the accuracy of predicting the chemical composition of submerged arc welding weld metal.

[0070] In some specific embodiments, the droplet collection device includes a cooling component and a conductive metal component. The cooling component is disposed at the lower end of the conductive metal component.

[0071] The droplet collection device can collect submerged arc welding droplets, and because the droplets are rapidly cooled, the collected droplets retain the reaction results in the arc cavity.

[0072] In some specific implementations, the cooling component is a water tank, see [link / reference]. Figure 1 As shown, the water tank is equipped with an inlet pipe and an outlet pipe, and the water tank contains cooling water.

[0073] In some specific implementations, the metallic conductive component is a copper plate.

[0074] The water tank has the function of storing circulating cooling water, the copper plate has the function of facilitating the conduction of electric arc and is different from the welding wire matrix, making it easy to calculate the composition change, and the installation of water inlet and outlet pipes facilitates the circulating cooling water to fully cool the copper plate.

[0075] In some specific embodiments, the droplet collection device further includes a welding machine for performing submerged arc welding.

[0076] In this invention, the droplet collection process is similar to the actual submerged arc welding process, but a droplet collection device is used instead of the welding steel plate. The droplet collection process is as follows: After the welding machine is turned on, the high temperature of the welding arc melts the welding wire and condenses it at the tip of the welding wire, while simultaneously melting the flux covering the copper plate. The welding wire melts and falls, and the flux components after melting and decomposition transition into droplets during the falling process. The droplets fall onto the copper plate, exchange heat with the circulating cooling water, and rapidly cool and solidify on the copper plate, such as... Figure 1 As shown, the above process does not form a molten pool.

[0077] In some specific implementations, any existing droplet collection device can be used for droplet collection, such as the device for collecting submerged arc welding droplets and characterizing arc plasma disclosed in patent CN114354282A, but it is not limited to this.

[0078] In some specific implementations, d = 0.5 to 0.7 includes, but is not limited to, any one of 0.5, 0.53, 0.55, 0.57, 0.6, 0.63, 0.65, 0.68, 0.7, or a range between any two.

[0079] The dilution ratio d depends on the ratio of the cross-sectional area of ​​the cladding metal to the cross-sectional area of ​​the molten pool metal in the weld.

[0080] In some specific implementations, the value of the dilution ratio d can be determined based on experience or big data background.

[0081] In some specific embodiments, the dilution ratio d = the cross-sectional area of ​​the diluted base material / the cross-sectional area of ​​the weld metal, that is, the ratio of the area of ​​the metal below the molten pool to the area of ​​the cladding metal above the molten pool.

[0082] In some specific embodiments, the welding wire includes at least one of CHW-S80 welding wire, H10Mn2 welding wire, H10Mn2q welding wire, and H08Mn2MoA welding wire.

[0083] In some specific embodiments, the base material includes steel.

[0084] In some specific embodiments, the steel includes at least one of EH36 steel, EH420 steel, EH460 steel, and EH550 steel.

[0085] In some specific embodiments, the error of the method for predicting the composition of submerged arc weld metal is ≤0.02 wt.%.

[0086] Secondly, the present invention provides the application of the above-mentioned method for predicting the composition of submerged arc welding weld metal in the preparation of flux and weldment.

[0087] Among them, welded parts refer to welded parts, that is, workpieces formed by welding.

[0088] The method for predicting the composition of submerged arc welding weld metal provided by this invention can regulate the composition of weld metal, enhance the microstructure and properties of welded joints, and is of great significance to the production and research and development of fluxes and weldments.

[0089] The embodiments of the present invention will be described in detail below with reference to examples. However, those skilled in the art will understand that the following examples are for illustrative purposes only and should not be considered as limiting the scope of the invention. Unless otherwise specified in the examples, conventional conditions or conditions recommended by the manufacturer are followed. Reagents or instruments whose manufacturers are not specified are all commercially available conventional products.

[0090] Example 1

[0091] The flux used in this embodiment is made from the following components by mass percentage: 30 wt.% CaO, 40 wt.% SiO2, and 30 wt.% MnO.

[0092] The partial composition of the H10Mn2 welding wire used in this embodiment is shown in Table 1 below.

[0093] Table 1. Elemental content of H10Mn2 welding wire

[0094] Content (wt.%) 0.08 0.0193 1.6391 0.0081 0.047 0.041 0.021 0.0028

[0095] The partial composition of the EH36 steel (base material) used in this embodiment is shown in Table 2 below.

[0096] Table 2. Elemental Contents of EH36 Steel

[0097] Content (wt.%) 0.12 0.137 1.5 0.0001 0.03 0.01 0.02

[0098] The method for predicting the composition of submerged arc welding weld metal provided in this embodiment includes the following steps:

[0099] (1) The molten droplet collection device disclosed in patent CN114354282A is used to collect cooled molten droplets. The molten droplet collection process is as follows: After the welding machine is turned on, the high temperature of the welding arc melts the welding wire and condenses it at the tip of the welding wire, while simultaneously melting the flux covering the copper plate. The welding wire melts and falls, and the flux components after melting and decomposition transition into molten droplets during the falling process. The molten droplets fall onto the copper plate, exchange heat with the circulating cooling water, and rapidly cool and solidify on the copper plate. The above process does not form a molten pool.

[0100] The top view of the molten droplet obtained in this embodiment is as follows: Figure 2 As shown.

[0101] (2) The chemical composition of the molten droplet was analyzed, and the content of O (mass percentage) was 0.1465 wt.%, the content of Mn (mass percentage) was 2.3323 wt.%, and the content of Si (mass percentage) was 0.2432 wt.%. The remaining elements are the combination of the welding wire and the base material, and are not affected by the composition of the flux. They have no special changes and do not need to be detected.

[0102] The oxygen content was determined using a LECO ONH836 instrument (oxygen, nitrogen, and hydrogen analyzer). The Mn and Si contents were determined using a Perkin Elmer Optima 8300 DVICPOES instrument (inductively coupled plasma atomic emission spectrometer).

[0103] Samples used for droplet composition analysis were taken directly, while samples used for weld composition analysis were taken from the center of the weld metal.

[0104] (3) Substitute the droplet composition into the weld metal composition prediction model. The calculation process is as follows:

[0105] (a) Calculate the ratio of the cross-sectional area of ​​the cladding metal to the cross-sectional area of ​​the molten pool metal in the weld, obtaining a dilution ratio d = 0.5143. Then, substitute the measured elemental content of the molten droplets into the formula Δ. droplet =(M droplet -M el )×(1-d):

[0106] Δ droplet-O =(M droplet-O -M el-O )×(1-d)=(0.1465wt.%-0.0081wt.%)×(1-0.5143)=

[0107] 0.0672 wt.%;

[0108] Δ droplet-Mn =(M droplet-Mn -M el-Mn )×(1-d)=(2.3323wt.%-1.6391wt.%)×(1-0.514

[0109] 3) = 0.3364 wt.%;

[0110] Δ droplet-Si =(M droplet-Si -M el-Si )×(1-d)=(0.2432wt.%-0.0193wt.%)×(1-0.5143)=

[0111] 0.1087 wt.%.

[0112] (b) Calculate the degree of transition Δ of the element to be predicted in the flux into the weld metal. WM :

[0113] Δ WM-O =0.61874×Δ droplet-O +0.05013=0.61874×0.0672wt.%+0.05013=0.09

[0114] 17wt.%;

[0115] Δ WM-Mn =1.0959×Δ droplet-Mn -0.11298=1.0959×0.3364wt.% -0.11298=0.2557

[0116] wt.%;

[0117] Δ WM-Si =0.706×Δ droplet-Si -0.01031=0.706×0.1087wt.% -0.01031=0.0664wt.%.

[0118] (c) Calculate the nominal composition M of the weld metal N M N =M BM ×d+M el ×(1-d):

[0119] M N-O =M BM-O ×d+M el-O ×(1-d)=0.0001wt.%×0.5143+0.0081wt.%×(1-0.514

[0120] 3) = 0.004 wt.%;

[0121] M N-Mn =M BM-Mn ×d+M el-Mn ×(1-d)=1.5wt.%×0.5143+1.6391wt.%×(1-0.514

[0122] 3) = 1.5676 wt.%;

[0123] M N-Si =M BM-Si ×d+M el-Si ×(1-d)=0.137wt.%×0.5143+0.0193wt.%×(1-0.514

[0124] 3) = 0.0798 wt.%.

[0125] (d) Calculate the predicted mass percentage of elemental composition P of the submerged arc weld metal. WM P WM =Δ WM +M N :

[0126] P WM-O =Δ WM-O +M N-O =0.0917wt.%+0.004wt.%=0.0957wt.%;

[0127] P WM-Mn =Δ WM-Mn +M N-Mn =0.2557wt.%+1.5676wt.%=1.8233wt.%;

[0128] P WM-Si =Δ WM-Si +M N-Si =0.0664wt.%+0.0798wt.%=0.1462wt.%.

[0129] That is, the mass percentage of O element predicted by the submerged arc welding weld metal composition prediction method provided in this embodiment is 0.0957 wt.%, the mass percentage of Mn element is 1.8233 wt.%, and the mass percentage of Si element is 0.1462 wt.%.

[0130] To verify the accuracy of the above prediction method, the chemical composition of the weld was analyzed (using the same instrument used to analyze the chemical composition of the molten droplets). The results showed that the mass percentage of O in the weld was 0.0947 wt.%, the mass percentage of Mn was 1.81 wt.%, and the mass percentage of Si was 0.1288 wt.%.

[0131] Example 2

[0132] The flux used in this embodiment is made from the following components by mass percentage: 10 wt.% CaO, 40 wt.% SiO2, and 50 wt.% MnO.

[0133] The partial composition of the CHW-S80 welding wire used in this embodiment is shown in Table 3 below.

[0134] Table 3. Elemental content of CHW-S80 welding wire

[0135] Content (wt.%) 0.084 0.18 1.75 0.0024 0.450 2.80 0.510

[0136] The partial composition content of the EH550 steel (base material) used in this embodiment is shown in Table 4 below.

[0137] Table 4. Elemental Contents of EH550 Steel

[0138] Content (wt.%) 0.047 0.21 1.34 0.0011 0.169 1.68 0.204

[0139] The method for predicting the composition of submerged arc welding weld metal provided in this embodiment includes the following steps:

[0140] (1) The molten droplet collection device disclosed in patent CN114354282A is used to collect cooled molten droplets. The molten droplet collection process is as follows: After the welding machine is turned on, the high temperature of the welding arc melts the welding wire and condenses it at the tip of the welding wire, while simultaneously melting the flux covering the copper plate. The welding wire melts and falls, and the flux components after melting and decomposition transition into molten droplets during the falling process. The molten droplets fall onto the copper plate, exchange heat with the circulating cooling water, and rapidly cool and solidify on the copper plate. The above process does not form a molten pool.

[0141] (2) The chemical composition of the molten droplet was analyzed, and the content of O (mass percentage) was 0.2090 wt.%, the content of Mn (mass percentage) was 2.6537 wt.%, and the content of Si (mass percentage) was 0.4528 wt.%. The remaining elements are the combination of the welding wire and the base material, and are not affected by the composition of the flux. They have no special changes and do not need to be detected.

[0142] The oxygen content was determined using a LECO ONH836 instrument (oxygen, nitrogen, and hydrogen analyzer). The Mn and Si contents were determined using a Perkin Elmer Optima 8300 DVICPOES instrument (inductively coupled plasma atomic emission spectrometer).

[0143] Samples used for droplet composition analysis were taken directly, while samples used for weld composition analysis were taken from the center of the weld metal.

[0144] (3) Substitute the droplet composition into the weld metal composition prediction model. The calculation process is as follows:

[0145] (a) Calculate the ratio of the cross-sectional area of ​​the cladding metal to the cross-sectional area of ​​the molten pool metal in the weld, obtaining a dilution ratio d = 0.5267. Then, substitute the measured elemental content of the molten droplets into the formula Δ. droplet =(M droplet -M el )×(1-d):

[0146] Δ droplet-O =(M droplet-O -M el-O )×(1-d)=(0.2090wt.%-0.0024wt.%)×(1-0.5267)=

[0147] 0.0978 wt.%;

[0148] Δ droplet-Mn =(M droplet-Mn -M el-Mn )×(1-d)=(2.6537wt.%-1.75wt.%)×(1-0.5267)=

[0149] 0.4277 wt.%;

[0150] Δ droplet-Si =(M droplet-Si -M el-Si )×(1-d)=(0.4528wt.%-0.18wt.%)×(1-0.5267)=0.

[0151] 1291 wt.%.

[0152] (b) Calculate the degree of transition Δ of the element to be predicted in the flux into the weld metal. WM :

[0153] Δ WM-O =0.61874×Δ droplet-O +0.05013=0.61874×0.0978wt.%+0.05013=0.110

[0154] 6wt.%;

[0155] Δ WM-Mn =1.0959×Δ droplet-Mn -0.11298=1.0959×0.4277wt.% -0.11298=0.3558

[0156] wt.%;

[0157] Δ WM-Si =0.706×Δ droplet-Si -0.01031=0.706×0.1291wt.% -0.01031=0.0808wt.%.

[0158] (c) Calculate the nominal composition M of the weld metal N M N =M BM ×d+M el ×(1-d):

[0159] M N-O =M BM-O ×d+M el-O ×(1-d)=0.0011wt.%×0.5267+0.0024wt.%×(1-0.526

[0160] 7) = 0.0017 wt.%;

[0161] M N-Mn =M BM-Mn ×d+M el-Mn ×(1-d)=1.34wt.%×0.5267+1.75wt.%×(1-0.5267)

[0162] = 1.5341 wt.%;

[0163] M N-Si =M BM-Si ×d+M el-Si ×(1-d)=0.21wt.%×0.5267+0.18wt.%×(1-0.5267)=0

[0164] 0.1958 wt.%.

[0165] (d) Calculate the predicted mass percentage of elemental composition P of the submerged arc weld metal. WM P WM =Δ WM +M N :

[0166] P WM-O =Δ WM-O +M N-O =0.1106wt.%+0.0017wt.%=0.1123wt.%;

[0167] P WM-Mn =Δ WM-Mn +M N-Mn =0.3558wt.%+1.5341wt.%=1.8899wt.%;

[0168] P WM-Si =Δ WM-Si +M N-Si =0.0808wt.%+0.1958wt.%=0.2766wt.%.

[0169] That is, the mass percentage of O element predicted by the submerged arc welding weld metal composition prediction method provided in this embodiment is 0.1123 wt.%, the mass percentage of Mn element is 1.8899 wt.%, and the mass percentage of Si element is 0.2766 wt.%.

[0170] To verify the accuracy of the above prediction method, the chemical composition of the weld was analyzed. The results showed that the mass percentage of O in the weld was 0.1036 wt.%, the mass percentage of Mn was 1.8741 wt.%, and the mass percentage of Si was 0.2594 wt.%.

[0171] Therefore, it can be seen that the element content values ​​predicted by the submerged arc welding weld metal composition prediction method provided by the present invention deviate from the actual values ​​by less than ±0.02 wt.%.

[0172] In summary, the method for predicting the composition of submerged arc weld metal provided by this invention is accurate, simple in procedure, and highly efficient. It solves the problems of high time and labor costs in the composition exploration process in actual production and R&D, and avoids the deviation problems of traditional prediction methods. Therefore, the method and apparatus for predicting the composition of submerged arc weld metal provided by this invention can be effectively applied to the welding of submerged arc welded steel plates.

[0173] Although the present invention has been illustrated and described with specific embodiments, it should be understood that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; those skilled in the art should understand that modifications can be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein, without departing from the spirit and scope of the present invention; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention; therefore, this means that all such substitutions and modifications that fall within the scope of the present invention are included in the appended claims.

Claims

1. A method for predicting the composition of submerged arc weld metal, characterized in that, Includes the following steps: A molten droplet is obtained, and its chemical composition is analyzed to obtain the mass percentage M of the element to be predicted in the molten droplet. droplet The flux used to form the droplets comprises the following components by mass percentage: CaO 10wt.%–55wt.%, SiO2 40wt.% and MnO 5wt.%–50wt.%; the element to be predicted includes at least one of O, Mn and Si. Calculate the degree Δ of the predicted element in the flux transitioning into the molten droplet. droplet Δ droplet =(M droplet -M el )×(1-d), where M el d represents the mass percentage of the element to be predicted in the welding wire, and d is the dilution ratio. Calculate the degree Δ of the predicted element in the flux transitioning into the weld metal. WM Δ WM Including Δ WM-O Δ WM-Mn and Δ WM-Si , where Δ WM-O =0.61874×Δ droplet +0.05013, Δ WM-Mn =1.0959×Δ droplet -0.11298, Δ WM-Si =0.706×Δ droplet -0.01031; Calculate the nominal composition M of the weld metal N M N =M BM ×d+M el ×(1-d), where M BM The mass percentage of the element to be predicted in the parent material; Calculate the predicted mass percentage of elemental composition P in the submerged arc weld metal. WM P WM =Δ WM +M N ; Wherein, the Δ is calculated droplet The M N and the P WM During the process, the corresponding mass percentage of the element to be predicted is substituted into the equation.

2. The method for predicting the composition of submerged arc weld metal according to claim 1, characterized in that, The cooled molten droplets are collected using a droplet collection device.

3. The method for predicting the composition of submerged arc weld metal according to claim 2, characterized in that, The droplet collection device includes a cooling component and a metal conductive component.

4. The method for predicting the composition of submerged arc weld metal according to claim 1, characterized in that, The value of d is 0.5 to 0.

7.

5. The method for predicting the composition of submerged arc weld metal according to claim 1, characterized in that, The value of d is the cross-sectional area of ​​the diluted base material divided by the cross-sectional area of ​​the weld metal.

6. The method for predicting the composition of submerged arc weld metal according to claim 1, characterized in that, The welding wire includes at least one of CHW-S80 welding wire, H10Mn2 welding wire, H10Mn2q welding wire and H08Mn2MoA welding wire.

7. The method for predicting the composition of submerged arc weld metal according to claim 1, characterized in that, The base material includes steel.

8. The method for predicting the composition of submerged arc weld metal according to claim 7, characterized in that, The steel includes at least one of EH36 steel, EH420 steel, EH460 steel, and EH550 steel.

9. The method for predicting the composition of submerged arc weld metal according to claim 1, characterized in that, The error of the method for predicting the composition of submerged arc weld metal is ≤0.02 wt.%.

10. The application of the method for predicting the composition of submerged arc welding weld metal as described in any one of claims 1 to 9 in the preparation of flux and weldment.

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