A method for preparing aluminum alloy welding wire containing rare earth elements

Abstract

The present application relates to the technical field of aluminum alloy welding wire, and specifically discloses a method for preparing aluminum alloy welding wire containing rare earth elements, comprising the following steps: smelting aluminum ingots, zinc ingots, magnesium ingots, copper ingots and aluminum-containing intermediate alloys containing Cr, Ti, Ce, Si, Mn, La, Fe, functional component A and functional component B respectively, and then performing fine treatment, and then casting to obtain welding wire rod blanks, and then drawing to obtain welding wire wire blanks, and then performing annealing treatment; then continuous drawing, peeling and cleaning after completion, and then drying to obtain aluminum alloy welding wire containing rare earth elements; functional component A is composed of Sr, Sm and Pr; functional component B is composed of Nd, Bi and Ca. In the process of melting and solidification of the aluminum alloy welding wire containing rare earth elements obtained by the present application, even if it is affected by the external environment and produces too fast cooling, the raw materials of each element can be more fully diffused and evenly distributed, and it is not easy to produce more brittle cracks near the solidification line.

Description

Technical Field

[0001] The present application relates to the technical field of aluminum alloy welding wires, and more specifically, to a method for preparing aluminum alloy welding wires containing rare earth elements. Background Art

[0002] Aluminum alloy welding wire is an important welding material used for welding aluminum and its alloys. Its main component is aluminum. After a series of process treatments, it forms a thin and long welding wire. Aluminum alloy welding wire has excellent electrical conductivity and thermal conductivity, which enables the heat to be quickly transferred to the welding part during welding, thereby improving welding efficiency. At the same time, the composition of aluminum alloy welding wire is pure, and the quality of the joint after welding is high. It also has good corrosion resistance and strength, which can meet the needs of different working environments. Therefore, aluminum alloy welding wire is widely used in aerospace, automobile manufacturing, architectural decoration, power equipment and other fields.

[0003] When processing aluminum alloy welding wire, in order to improve its performance, it is usually necessary to add some rare earth elements; rare earth elements can improve welding performance, refine grains, reduce pores and crack defects during welding, thereby improving the strength and toughness of welded joints; they can also react with gases such as hydrogen and non-metallic elements to generate high-melting-point compounds, effectively remove gases and impurities in the weld, and further improve welding quality. At the same time, the addition of rare earth elements can significantly improve the strength and toughness of aluminum alloy welding wire, prevent it from corroding in a humid environment, and extend the service life of the weld.

[0004] With respect to the above-mentioned related technologies, the inventors believe that, during the welding process, the aluminum alloy welding wire containing rare earths liquefies due to the high temperature to form a liquid phase with a low melting point. During the solidification process, if these liquid phases are affected by the external environment and cool too quickly, the various elemental raw materials contained therein are often unable to fully diffuse and form a uniform distribution, which in turn causes the structure near the solidification line to be too brittle and prone to more brittle cracks.

[0005] Therefore, it is urgent to propose a solution to solve the above technical problems. Summary of the invention

[0006] In order to prevent the aluminum alloy welding wire containing rare earth elements from generating many brittle cracks near the solidification line under excessively fast cooling conditions during welding applications and to ensure the stability of the weld, the present application provides a method for preparing aluminum alloy welding wire containing rare earth elements.

[0007] The present application provides a method for preparing an aluminum alloy welding wire containing rare earth elements, which adopts the following technical solution:

[0008] A method for preparing an aluminum alloy welding wire containing rare earth elements comprises the following steps:

[0009] (1) melting aluminum ingots, zinc ingots, magnesium ingots, copper ingots, and aluminum-containing master alloys containing Cr, Ti, Ce, Si, Mn, La, Fe, functional component A, and functional component B, respectively, to obtain a mixed solution;

[0010] (2) performing fine treatment on the mixed solution obtained in step (1) to obtain a refined solution;

[0011] (3) casting the solution obtained in step (2) to obtain a welding wire rod blank, drawing the same to obtain a welding wire blank, and then annealing the same;

[0012] (4) continuously drawing the annealed welding wire blank obtained in step (3), peeling and cleaning the wire blank after the drawing, and drying the wire blank to obtain an aluminum alloy welding wire containing rare earth elements;

[0013] Among them, the aluminum alloy welding wire containing rare earth elements includes the following components in terms of mass percentage:

[0014] Zn 0.6-1.2%;

[0015] Mg 3-6%;

[0016] Cu 0.01-0.1%;

[0017] Cr 0.1-0.4%;

[0018] Ti 0.1-0.2%;

[0019] Ce 0.15-0.25%;

[0020] Si 0.05-0.2%;

[0021] Mn 0.05-0.2%;

[0022] La 0.01-0.05%;

[0023] Fe 0.15-0.3%;

[0024] Functional component A 0.4-0.8%;

[0025] Functional component B 2-3%;

[0026] Impurities ≤ 0.15%;

[0027] The balance is Al;

[0028] The functional component A is composed of Sr, Sm and Pr, and the mass ratio of Sr, Sm and Pr is 1:(9-11):(3-5);

[0029] The functional component B consists of Nd, Bi and Ca, and the mass ratio of Nd, Bi and Ca is (4-5):1:(30-40).

[0030] By adopting the above technical scheme, in the functional component A, Sr can make the organizational structure of the molten aluminum alloy welding wire containing rare earth elements change from coarse needle shape to fine and uniform fiber shape during the solidification process; Sm can not only reduce the porosity of the weld, but also promote the uniform and stable distribution of the raw materials of each element during the cooling and solidification process of the aluminum alloy welding wire containing rare earth elements; Pr can bring about the grain refinement effect, and make the aluminum alloy welding wire containing rare earth elements keep its grain boundary stable and its grain distribution more uniform during the transformation from molten liquid to solidified state; at the same time, the synergy between Sr, Sm and Pr makes it difficult for the aluminum alloy welding wire containing rare earth elements to produce more brittle cracks near the solidification line under too fast cooling conditions during the welding application process, thereby ensuring the stability of the weld.

[0031] Among the functional components B, Nd has a better effect on the grain refinement of the weld, and can improve the tissue distribution of the aluminum alloy welding wire containing rare earth elements after being melted during the solidification process; Bi can lower the melting point of the aluminum alloy welding wire containing rare earth elements, reduce the adverse effects of too fast cooling to a certain extent, and improve the wettability, so that the aluminum alloy welding wire containing rare earth elements can spread quickly and evenly after melting; Ca can improve the density of the weld, reduce the formation of pores, and make it easier for the aluminum alloy welding wire containing rare earth elements to cover and fill the welding part after melting; at the same time, the synergy between Nd, Bi and Ca makes it difficult for the aluminum alloy welding wire containing rare earth elements to produce more brittle cracks near the solidification line under too fast cooling conditions during the welding application process, thereby ensuring the stability of the weld.

[0032] Finally, the present application mainly utilizes the combination between functional component A and functional component B, which can bring about a compound synergistic effect, so that during the melting and solidification process of the aluminum alloy welding wire containing rare earth elements, even if it is affected by the external environment and cools too quickly, the raw materials of each element can be diffused more fully and form a uniform distribution, and it is not easy to produce many brittle cracks near the solidification line, so that excellent and stable welds can be obtained.

[0033] Moreover, the above preparation steps are few, the process is simple, and it is convenient for large-scale industrial production. At the same time, the above operation is relatively simple for the use of raw materials, especially for the use of raw materials containing functional component A and functional component B. Only through one-pot mixing and processing, functional component A and functional component B can play an excellent and stable coordination effect in the subsequent product application process, thereby obtaining an aluminum alloy welding wire containing rare earth elements with better application quality.

[0034] Preferably, in the functional component A, the mass ratio of Sr, Sm and Pr is 1:10:3.5.

[0035] By adopting the above technical scheme, when Sr, Sm and Pr in the above mass ratio are used to form the functional component A, they have a better coordination effect with each other and a more significant synergistic effect, so that the aluminum alloy welding wire containing rare earth elements has better overall stability during the welding application process, even if it is affected by the external environment and cooled too quickly, and is not prone to more brittle cracks.

[0036] Preferably, in the functional component B, the mass ratio of Nd, Bi and Ca is 4.5:1:36.

[0037] By adopting the above technical scheme, when Nd, Bi and Ca in the above mass ratio are used to form the functional component B, they have a better coordination effect with each other and a more significant synergistic effect, so that the aluminum alloy welding wire containing rare earth elements has better overall stability during the welding application process, even if it is affected by the external environment and cooled too quickly, and is not prone to more brittle cracks.

[0038] Preferably, the mass ratio of the functional component A to the functional component B is 0.24:1.

[0039] By adopting the above technical scheme, functional component A and functional component B can form a relatively complete and sufficient coordination, and the synergistic effect brought about is also more significant, so that the aluminum alloy welding wire containing rare earth elements has a stronger ability to resist the excessive cooling caused by the external environment during the melting and solidification process, and the combination of each element raw material is tighter and the distribution is more even, which makes it less likely to produce more brittle cracks, thereby obtaining a better quality weld.

[0040] Preferably, in step (1), the smelting temperature is 720-800°C and the smelting time is 2-3h.

[0041] By adopting the above technical scheme, if the melting temperature is low and the melting time is too short, the welding quality caused by the application of aluminum alloy welding wire containing rare earth elements will be poor, and the weld will be prone to defects such as cracks and pores; if the melting temperature is high and the melting time is too long, it is easy to produce metal particles that are too large or too small, and even cause molten particle inclusions during welding, thereby reducing the welding quality; and the selection of the above melting temperature and melting time can obtain a better melting effect.

[0042] Preferably, in step (2), the refining temperature is 800-880°C and the refining time is 20-30 min.

[0043] By adopting the above technical scheme, refining can remove impurities and oxides, improve the purity of the aluminum alloy, and improve the physical and chemical properties of the aluminum alloy during the preparation of aluminum alloy welding wire containing rare earth elements; and the selection of the above refining temperature and refining time can obtain better refining effect, which is conducive to obtaining aluminum alloy welding wire containing rare earth elements of better quality.

[0044] Preferably, in step (2), an inert gas is introduced during the refining process, and the inert gas is any one of nitrogen and argon or a mixture of the two in any mass ratio.

[0045] By adopting the above technical solution, inert gas is introduced, and the above process of bubbles is utilized to bring out hydrogen to achieve the degassing effect, and to bring out oxidized impurities to the surface of the smelting liquid, which is beneficial to the subsequent slag removal, thereby achieving the effect of enhanced refining; nitrogen and argon are non-toxic, non-corrosive, and relatively low in price, and the effects they bring are also the most excellent.

[0046] Preferably, in step (3), the diameter of the welding wire rod blank is 7-9 mm, and the diameter of the welding wire blank is 3-5 mm; and in step (4), the diameter of the aluminum alloy welding wire containing rare earth elements is 1.2-1.6 mm.

[0047] By adopting the above technical solution, drawing is a common forming process used to change the shape and size of the material. In the preparation process of aluminum alloy welding wire containing rare earth elements, the selection of the above diameter can obtain a better graded drawing effect, which is conducive to the reasonable control of deformability and ensures the uniformity and stability of the combination of various element components, thereby obtaining aluminum alloy welding wire containing rare earth elements of better quality.

[0048] Preferably, step (3) is specifically configured as follows: the solution obtained in step (2) is cast to obtain a welding wire rod blank, which is then drawn to obtain a welding wire blank after being kept at 160-200°C for 18-20 hours, and then annealed at a temperature of 360-420°C for 2-3 hours.

[0049] By adopting the above technical solution, the aluminum alloy has high thermal conductivity and thermal expansion coefficient, but is also easily affected by oxidation. The heat preservation operation at the above temperature can make the aluminum alloy deform evenly during the initial drawing process, which is beneficial to prevent the occurrence of cracks; at the same time, the selection and combination of the above annealing temperature and time can achieve better elimination of internal stress and improvement of organizational structure, which is beneficial to subsequent processing, thereby ensuring that the final quality of aluminum alloy welding wire containing rare earth elements is better.

[0050] In summary, this application has the following beneficial effects:

[0051] The present application uses a functional component A composed of Sr, Sm and Pr, and a functional component B composed of Nd, Bi and Ca, and through the synergistic effect of the compounding between the functional components A and B, it is possible to make the aluminum alloy welding wire containing rare earth elements diffuse more fully and form a uniform distribution during the melting and solidification process even if it is affected by the external environment and cools too quickly, and it is not easy to produce many brittle cracks near the solidification line, so that a weld with excellent and stable quality can be obtained. DETAILED DESCRIPTION

[0052] The present application is further described in detail below in conjunction with embodiments and comparative examples.

[0053] Unless otherwise specified, the raw materials used in the embodiments and comparative examples of the present application are commercially available.

[0054] Example

[0055] Example 1

[0056] A method for preparing an aluminum alloy welding wire containing rare earth elements comprises the following steps:

[0057] (1) melting aluminum ingots, zinc ingots, magnesium ingots, copper ingots and aluminum-containing master alloys containing Cr, Ti, Ce, Si, Mn, La, Fe, functional component A and functional component B respectively at a melting temperature of 760° C. for 2.5 h to obtain a mixed solution;

[0058] (2) performing a refining treatment on the mixed solution obtained in step (1), wherein the refining temperature is 840° C. and the refining time is 25 min to obtain a refined solution;

[0059] (3) The melt obtained in step (2) is cast to obtain a welding wire rod blank having a diameter of 8 mm, and is kept at 180° C. for 19 h to obtain a welding wire blank having a diameter of 4 mm, and then annealed at 390° C. for 2.5 h;

[0060] (4) The annealed welding wire blank obtained in step (3) is continuously drawn, peeled and cleaned, and then dried to obtain an aluminum alloy welding wire containing rare earth elements with a diameter of 1.4 mm.

[0061] Note: Functional component A is composed of Sr, Sm and Pr, and the mass ratio of Sr, Sm and Pr is 1:10:3.5; functional component B is composed of Nd, Bi and Ca, and the mass ratio of Nd, Bi and Ca is 4.5:1:36; in step (2), an inert gas is introduced during the refining process, and the inert gas is argon; and the aluminum alloy welding wire containing rare earth elements, in terms of mass percentage, includes components and their corresponding mass percentages as shown in Table 1.

[0062] Example 2-3

[0063] A method for preparing an aluminum alloy welding wire containing rare earth elements, which is different from Example 1 in that the aluminum alloy welding wire containing rare earth elements includes components and their corresponding mass percentages as shown in Table 1.

[0064] Table 1 Components and their corresponding mass percentages (%) of the aluminum alloy welding wire containing rare earth elements in Examples 1-3

[0065] raw material Example 1 Example 2 Example 3 Zn 0.9 0.6 1.2 Mg 4.5 3 6 Cu 0.05 0.01 0.1 Cr 0.25 0.1 0.4 Ti 0.15 0.1 0.2 Ce 0.2 0.15 0.25 Si 0.125 0.05 0.2 Mn 0.125 0.05 0.2 La 0.03 0.01 0.05 Fe 0.225 0.15 0.3 Functional component A 0.6 0.4 0.8 Functional component B 2.5 2 3 Impurities 0.1 0.12 0.11 Al margin margin margin

[0066] Example 4

[0067] A method for preparing an aluminum alloy welding wire containing rare earth elements, which is different from Example 1 in that the functional component A consists of Sr, Sm and Pr, and the mass ratio of Sr, Sm and Pr is 1:9:3.

[0068] Example 5

[0069] A method for preparing an aluminum alloy welding wire containing rare earth elements, which is different from Example 1 in that the functional component A consists of Sr, Sm and Pr, and the mass ratio of Sr, Sm and Pr is 1:11:5.

[0070] Example 6

[0071] A method for preparing an aluminum alloy welding wire containing rare earth elements, which is different from Example 1 in that the functional component A consists of Sr, Sm and Pr, and the mass ratio of Sr, Sm and Pr is 1:10:4.

[0072] Example 7

[0073] A method for preparing an aluminum alloy welding wire containing rare earth elements, which is different from Example 1 in that functional component B consists of Nd, Bi and Ca, and the mass ratio of Nd, Bi and Ca is 4:1:30.

[0074] Example 8

[0075] A method for preparing an aluminum alloy welding wire containing rare earth elements, which is different from Example 1 in that functional component B consists of Nd, Bi and Ca, and the mass ratio of Nd, Bi and Ca is 5:1:40.

[0076] Example 9

[0077] A method for preparing an aluminum alloy welding wire containing rare earth elements, which is different from Example 1 in that functional component B consists of Nd, Bi and Ca, and the mass ratio of Nd, Bi and Ca is 4.5:1:35.

[0078] Example 10

[0079] A method for preparing an aluminum alloy welding wire containing rare earth elements, which is different from Example 1 in that the total mass percentage of functional component A and functional component B remains unchanged, and the mass ratio of the two is adjusted to 0.24:1.

[0080] Embodiment 11

[0081] A method for preparing an aluminum alloy welding wire containing rare earth elements, which is different from Example 1 in that, in step (1), the melting temperature is 720° C. and the melting time is 3 hours.

[0082] Example 12

[0083] A method for preparing an aluminum alloy welding wire containing rare earth elements, which is different from Example 1 in that, in step (1), the smelting temperature is 800° C. and the smelting time is 2 h.

[0084] Example 13

[0085] A method for preparing an aluminum alloy welding wire containing rare earth elements, which is different from Example 1 in that, in step (2), the refining temperature is 800° C. and the refining time is 30 min.

[0086] Embodiment 14

[0087] A method for preparing an aluminum alloy welding wire containing rare earth elements, which is different from that of Example 1 in that, in step (2), the refining temperature is 880° C. and the refining time is 20 min.

[0088] Embodiment 15

[0089] A method for preparing an aluminum alloy welding wire containing rare earth elements, which is different from Example 1 in that in step (3), the diameter of the welding wire rod blank is 7 mm, and the diameter of the welding wire blank is 3 mm; in step (4), the diameter of the aluminum alloy welding wire containing rare earth elements is 1.2 mm.

[0090] Example 16

[0091] A method for preparing an aluminum alloy welding wire containing rare earth elements, which is different from Example 1 in that in step (3), the diameter of the welding wire rod blank is 9 mm, and the diameter of the welding wire blank is 5 mm; in step (4), the diameter of the aluminum alloy welding wire containing rare earth elements is 1.6 mm.

[0092] Embodiment 17

[0093] A method for preparing an aluminum alloy welding wire containing rare earth elements, which is different from Example 1 in that the melt obtained in step (2) is cast to obtain a welding wire rod blank, which is then drawn to obtain a welding wire blank after being kept at 160° C. for 20 hours, and then annealed at 360° C. for 3 hours.

[0094] Embodiment 18

[0095] A method for preparing an aluminum alloy welding wire containing rare earth elements, which is different from Example 1 in that the melt obtained in step (2) is cast to obtain a welding wire rod blank, which is then drawn to obtain a welding wire blank after being kept at 200°C for 18 hours, and then annealed at 420°C for 2 hours.

[0096] Comparative Example

[0097] Comparative Example 1

[0098] A method for preparing an aluminum alloy welding wire containing rare earth elements, which is different from Example 1 in that the components used do not contain functional component A.

[0099] Comparative Example 2

[0100] A method for preparing an aluminum alloy welding wire containing rare earth elements, which is different from Example 1 in that the components used do not contain functional component B.

[0101] Comparative Example 3

[0102] A method for preparing an aluminum alloy welding wire containing rare earth elements, which is different from Example 1 in that the components used do not contain functional component A and functional component B.

[0103] Comparative Example 4

[0104] A method for preparing an aluminum alloy welding wire containing rare earth elements, which is different from Example 1 in that the functional component A does not contain Sr.

[0105] Comparative Example 5

[0106] A method for preparing an aluminum alloy welding wire containing rare earth elements, which is different from Example 1 in that the functional component A does not contain Sm.

[0107] Comparative Example 6

[0108] A method for preparing an aluminum alloy welding wire containing rare earth elements, which is different from Example 1 in that functional component A does not contain Pr.

[0109] Comparative Example 7

[0110] A method for preparing an aluminum alloy welding wire containing rare earth elements, which is different from Example 1 in that functional component B does not contain Nd.

[0111] Comparative Example 8

[0112] A method for preparing an aluminum alloy welding wire containing rare earth elements, which is different from Example 1 in that functional component B does not contain Bi.

[0113] Comparative Example 9

[0114] A method for preparing an aluminum alloy welding wire containing rare earth elements, which is different from Example 1 in that functional component B does not contain Ca.

[0115] Performance testing

[0116] Test samples: The aluminum alloy welding wire containing rare earth elements obtained by applying the method for preparing aluminum alloy welding wire containing rare earth elements in Example 1-18 is used as test sample 1-18, and the aluminum alloy welding wire containing rare earth elements obtained by applying the method for preparing aluminum alloy welding wire containing rare earth elements in Comparative Example 1-9 is used as control sample 1-9.

[0117] Test method: automatic welding method is adopted, welding speed is 300mm / min, welding test plate is Q235 (300mm×200mm×20mm), and the surface of the test plate is ground and polished. The length of each weld is 250mm. After welding, the temperature of the test plate is controlled within 100℃ for the next welding, and the distance between each weld is 10mm. During welding, the welding current is 180A, the welding voltage is 25V, the dry extension length is 20mm unchanged, and the argon gas flow is 20L / min.

[0118] In a working environment with a temperature of 25°C, using aluminum alloy welding wire containing rare earth elements, the surface crack rate was tested according to the requirements of standard GB / T4675.1-1984 "Weldability Test Slanted Y-Groove Welding Crack Test Method", and the surface crack rate value was M.

[0119] In a working environment with a temperature of 5°C, using aluminum alloy welding wire containing rare earth elements, the surface crack rate was tested according to the requirements of standard GB / T4675.1-1984 "Weldability Test Oblique Y-Groove Welding Crack Test Method", and the surface crack rate value was N.

[0120] Then calculate the surface crack growth rate, surface crack growth rate = (N-M) / M. The smaller the surface crack growth rate, the stronger the ability of the aluminum alloy welding wire containing rare earth elements to resist the excessive cooling caused by the external environment during welding application, and the less likely it is to produce more brittle cracks.

[0121] After completing the above tests on test samples 1-18 and control samples 1-9, the test results are recorded in Table 2 accordingly.

[0122] Table 2 Test results of test samples 1-18 and control samples 1-9

[0123] sample Crack growth rate (%) Test sample 1 12.8 Test sample 2 13.5 Test sample 3 13.1 Test sample 4 13.9 Test sample 5 13.4 Test sample 6 12.9 Test sample 7 13.6 Test sample 8 13.7 Test sample 9 13.0 Test sample 10 12.3 Test sample 11 13.2 Test sample 12 13.8 Test sample 13 14.3 Test sample 14 13.5 Test sample 15 14.2 Test sample 16 14.0 Test sample 17 14.1 Test sample 18 14.4 Control sample 1 47.6 Control sample 2 45.2 Control sample 3 68.9 Control sample 4 31.8 Control sample 5 32.0 Control sample 6 31.7 Control sample 7 31.0 Control sample 8 30.8 Control sample 9 31.3

[0124] It can be seen from Example 1 and Comparative Examples 1-3 and Table 2 that by using functional component A composed of Sr, Sm and Pr, and functional component B composed of Nd, Bi and Ca, and through the compounding synergistic effect between functional component A and functional component B, the crack growth rate can be significantly reduced, indicating that in the process of melting and solidification of the aluminum alloy welding wire containing rare earth elements, even if it is affected by the external environment and produces too fast cooling, it is not easy to produce more brittle cracks, and a weld with excellent quality and stability can be obtained. If any one of functional component A and functional component B is applied alone to the aluminum alloy welding wire containing rare earth elements, although the crack growth rate can be reduced, the effect is limited, and the sum of the corresponding effects brought by the two alone is far less than the excellent effect brought by the compounding of the two. It can be seen that the combination of functional component A and functional component B can bring a significant improvement effect of 1+1>2. Combined with Comparative Examples 4-9 and Table 2, it can be seen that when one of the components in functional component A or functional component B is missing, the corresponding effect of the coordination between functional component A and functional component B will be significantly reduced, indicating that Sr, Sm and Pr in functional component A and Nd, Bi and Ca in functional component B are the basis for ensuring that functional component A and functional component B have an excellent compound synergistic effect, and none of them can be missing.

[0125] It can be seen from Example 1 and Examples 4-6 and Table 2 that when the functional component A is composed of Sr, Sm and Pr in a mass ratio of 1: (9-11): (3-5), it can cooperate with the functional component B to exert an excellent and stable effect. Among them, when the mass ratio of Sr, Sm and Pr is 1:10:3.5, the crack growth rate of the aluminum alloy welding wire containing rare earth elements obtained by the above test is relatively low.

[0126] It can be seen from Example 1 and Examples 7-9 and Table 2 that when the functional component B is composed of Nd, Bi and Ca in a mass ratio of (4-5):1:(30-40), it can cooperate with the functional component S to exert an excellent and stable effect. Among them, when the mass ratio of Nd, Bi and Ca is 4.5:1:36, the crack growth rate of the aluminum alloy welding wire of rare earth elements obtained by the above test is relatively low.

[0127] It can be seen from Examples 1-3 and 10 and Table 2 that the mass ratio of functional component A to functional component B is 0.24:1, and the synergistic effect brought about is also quite significant, so that the aluminum alloy welding wire containing rare earth elements has a stronger ability to resist excessive cooling caused by the external environment during the melting and solidification process, and is less likely to produce more brittle cracks.

[0128] It can be seen from Example 1 and Examples 11-18 and Table 2 that in the preparation of aluminum alloy welding wire containing rare earth elements, the parameter control in each operation process described above can ensure that a stable and better combination state is formed between the components, thereby obtaining an aluminum alloy welding wire containing rare earth elements with better application quality.

[0129] This specific embodiment is merely an explanation of the present application and is not a limitation of the present application. After reading this specification, those skilled in the art may make modifications to the present embodiment without any creative contribution as needed, but such modifications are protected by the patent law as long as they are within the scope of the claims of the present application.

Claims

1. A method for preparing an aluminum alloy welding wire containing rare earth elements, characterized in that: The following steps are involved: (1) melting aluminum ingots, zinc ingots, magnesium ingots, copper ingots, and aluminum-containing master alloys containing Cr, Ti, Ce, Si, Mn, La, Fe, functional component A, and functional component B, respectively, to obtain a mixed solution; (2) performing fine treatment on the mixed solution obtained in step (1) to obtain a refined solution; (3) The solution obtained in step (2) is cast to obtain a welding wire rod blank, which is then drawn to obtain a welding wire blank after being kept at 160-200°C for 18-20 hours, and then annealed at 360-420°C for 2-3 hours; (4) continuously drawing the annealed welding wire blank obtained in step (3), peeling and cleaning the wire blank after the drawing, and drying the wire blank to obtain an aluminum alloy welding wire containing rare earth elements; Among them, the aluminum alloy welding wire containing rare earth elements includes the following components in terms of mass percentage: Zn 0.6-1.2%; Mg 3-6%; Cu 0.01-0.1%; Cr 0.1-0.4%； Ti 0.1-0.2%; Ce 0.15-0.25%; Si 0.05-0.2%; Mn 0.05-0.2%; La 0.01-0.05%; Fe 0.15-0.3%; Functional component A 0.4-0.8%; Functional component B 2-3%; Impurities ≤ 0.15%; The balance is Al; The functional component A is composed of Sr, Sm and Pr, and the mass ratio of Sr, Sm and Pr is 1:(9-11):(3-5); The functional component B consists of Nd, Bi and Ca, and the mass ratio of Nd, Bi and Ca is (4-5):1:(30-40); In step (1), the smelting temperature is 720-800°C and the smelting time is 2-3h; In step (2), the refining temperature is 800-880°C, the refining time is 20-30 min, and an inert gas is introduced during the refining process. The inert gas is any one of nitrogen and argon or a mixture of the two in any mass ratio; In step (3), the diameter of the welding wire rod blank is 7-9 mm, and the diameter of the welding wire blank is 3-5 mm; in step (4), the diameter of the aluminum alloy welding wire containing rare earth elements is 1.2-1.6 mm.

2. The method for preparing an aluminum alloy welding wire containing rare earth elements according to claim 1, characterized in that: In the functional component A, the mass ratio of Sr, Sm and Pr is 1:10:3.

5.

3. The method for preparing an aluminum alloy welding wire containing rare earth elements according to claim 1, characterized in that: In the functional component B, the mass ratio of Nd, Bi and Ca is 4.5:1:

36.

4. The method for preparing an aluminum alloy welding wire containing rare earth elements according to claim 1, characterized in that: The mass ratio of the functional component A to the functional component B is 0.24:1.