An aluminum alloy welding wire for fusion welding of 6-series aluminum alloy and its preparation method

Abstract

The present invention belongs to the technical field of aluminum alloy welding wires, and relates to an aluminum alloy welding wire for fusion welding of 6-series aluminum alloys and a preparation method thereof. The aluminum alloy welding wire comprises: Mg: 0.4 - 1.5 wt%; Si: 0.2 - 1.5 wt%; Zr: 0.1 - 0.3 wt%; Ti: 0.005 - 0.095 wt%; La and / or Ce: 0.0005 - 0.15 wt%; W1: 0.005 - 0.16 wt%, and the content of any one of Li, Na, K, Ca, Rb, Cs is less than 0.001 wt% respectively; the mass ratio of Mg to Si is 1 - 2:1; the balance is aluminum and inevitable impurity elements. Through alloying treatment, the sensitivity to hot cracks during welding is reduced, the comprehensive properties of the material are optimized and regulated, and it has excellent welding effects when welding 6-series aluminum alloys, can solve the problem of non-homogeneity between the weld and the base metal, and its formula is relatively economical.

Description

Technical Field

[0001] The present invention belongs to the technical field of aluminum alloy welding wires, and relates to an aluminum alloy welding wire for fusion welding of 6-series aluminum alloys and a preparation method thereof. Background Art

[0002] 6-series aluminum alloys (Al-Mg-Si series) are heat-treatable alloys mainly strengthened by the precipitation of Mg2Si phase. Because of their easy processing and forming, and good mechanical properties and corrosion resistance, this series of aluminum alloys are often used in occasions with lightweight and good strength requirements, such as some structural parts in the fields of architecture, automobiles, ships, etc., and the casings of some electronic devices.

[0003] During the material connection process of 6-series aluminum alloys, welding or riveting is often used. In the welding process, it is pursued that the weld and the base metal are as homogeneous as possible to obtain uniform composition and properties at the welded joint and ensure the stable service state of the material. However, a second phase with a low melting point will form at the end of solidification of 6-series aluminum alloys, and liquation cracks are likely to occur after welding. And the high heat input brought by welding makes the weld and the base metal in an over-aged state. These two reasons lead to high thermal crack sensitivity and low post-weld strength when traditional 6-series alloys are welded. Therefore, traditional 4-series (Al-Si series) or 5-series (Al-Mg series) welding wires are often used to weld 6-series aluminum alloys, but this will lead to inconsistent composition between the welded part of the material and the base metal, and then lead to large differences in the properties of various parts of the joint structure. At the same time, due to the compositional differences, it is not conducive to the subsequent recycling and reprocessing of aluminum alloys. For 6-series alloys with requirements for homogenization and high strength in welding, friction stir welding is often used, but it is difficult to apply this welding method to large-scale or complex structural parts.

[0004] Currently, there are also a few new welding wire inventions for the welding application of 6-series aluminum alloys. For example, in patent CN110977237A, while reducing the addition amount of transition elements Cu, Mn, and Cr on the basis of the Al-Mg system, Ti and Zr are added to prepare a welding wire for 6-series aluminum alloy templates; another example is in patent CN118002980A, Zr and Sc elements are added on the basis of the Al-Mg system to reduce welding liquation cracks and improve post-weld strength, and a welding wire for welding 6-series aluminum alloy extrusions is prepared. Most of these patents are still optimized and modified mainly based on the 4-series or 5-series, and cannot solve the problem of homogenization between the welding material and the base metal. Very few inventions are mainly designed for welding wires based on the Al-Mg-Si system, but add a large variety of chemical elements or high-unit-price chemical elements, which are difficult to manufacture and costly, and are not conducive to mass production or popularization and application.

[0005] Therefore, it is very necessary to develop a 6xxx series aluminum alloy welding wire with a weld composition similar to that of the 6xxx series aluminum alloy base material after welding, with an economical manufacturing cost and good welding effect. Summary of the Invention

[0006] To solve the problems existing in the welding of 6xxx series aluminum alloys in the prior art, the purpose of the present invention is to provide an aluminum alloy welding wire for the fusion welding of 6xxx series aluminum alloys to overcome the deficiencies of the prior art.

[0007] One object of the present invention is achieved by the following technical solutions:

[0008] An aluminum alloy welding wire for the fusion welding of 6xxx series aluminum alloys, the aluminum alloy welding wire comprising the following components in weight percentage:

[0009] Mg: 0.4 - 1.5 wt%; Si: 0.2 - 1.5 wt%; Zr: 0.1 - 0.3 wt%; Ti: 0.005 - 0.095 wt%;

[0010] La and / or Ce: 0.0005 - 0.15 wt%;

[0011] Trace element W1: 0.005 - 0.16 wt%, the trace element W1 being one or more of Cu, Mn, Cr, B, Sr;

[0012] The content of any one of the elements Li, Na, K, Ca, Rb, Cs is less than 0.001 wt% respectively;

[0013] The mass ratio of Mg to Si is 1 - 2:1;

[0014] The balance is aluminum and unavoidable impurity elements.

[0015] Preferably, the Si is 0.47 - 1.0 wt%.

[0016] Preferably, the trace element W1 is Cu, Mn, Cr, B and Sr.

[0017] Preferably, the weight percentages of Cu, Mn, Cr, B, Sr are 0.005 - 0.1 wt% respectively.

[0018] Preferably, the impurity elements include the following elements in weight percentage: Pb ≤ 0.015 wt%, Sb ≤ 0.015 wt%, Bi ≤ 0.015 wt%, Te ≤ 0.015 wt%, S ≤ 0.015 wt%, Fe ≤ 0.40 wt%, Zn ≤ 0.030 wt%.

[0019] Preferably, when the aluminum alloy welding wire welds a 6xxx series aluminum alloy substrate, the tensile strength of the weld is not less than 0.65 times the tensile strength of the 6xxx series aluminum alloy substrate.

[0020] Another object of the present invention is achieved by the following technical solution:

[0021] A preparation method of an aluminum alloy welding wire for melting welding of 6-series aluminum alloy, comprising the following steps:

[0022] (1) Mix the raw materials required for the aluminum alloy welding wire components and carry out melting and casting to form an aluminum alloy ingot;

[0023] (2) Process the aluminum alloy ingot into an extrusion ingot, and prepare a mother rod by hot extrusion;

[0024] (3) Obtain a bus bar after the first plastic processing of the mother rod;

[0025] (4) Carry out intermediate annealing on the bus bar, and then obtain a finished billet after the second plastic processing;

[0026] (5) The finished billet undergoes steps including peeling and packaging to obtain the final aluminum alloy welding wire.

[0027] Preferably, the alloy melting temperature in step (1) is 780 - 850 °C, and the casting temperature is 680 - 750 °C.

[0028] Preferably, the specific steps of step (1) include: aluminum is added in the form of industrial pure aluminum, and other additive elements are added in the form of aluminum-based master alloys, and are formulated according to the weight percentage of the formula; all raw materials are put into a melting and casting furnace, heated to the alloy melting temperature, after the alloy melts, add chloride salt for refining, then carry out argon purging and let stand for 5 - 30 min; after standing is completed, remove the melt scum, and then cool the melt to the casting temperature for casting to form an aluminum alloy ingot.

[0029] Preferably, in step (2), the aluminum alloy ingot is first subjected to homogenization annealing treatment, the annealing temperature is 500 - 570 °C, the holding time is 12 - 24 h, and then it is machined to obtain an extrusion ingot with appropriate specifications.

[0030] Preferably, in step (2), during the hot extrusion process, the preheating temperature of the extrusion cylinder and the extrusion die is 350 - 450 °C, and the extrusion temperature is 380 - 480 °C.

[0031] Preferably, the specification of the mother rod prepared by hot extrusion is Ф6 - Ф13 mm.

[0032] Preferably, the bus bar obtained after the first plastic processing of the mother rod has a specification of Ф2.0 - Ф4.2 mm.

[0033] Preferably, the annealing temperature for the intermediate annealing of the bus bar is 340 - 400 °C, and the holding time is 4 - 24 h.

[0034] Preferably, the annealed bus bar is subjected to a second plastic working to obtain a finished billet with a specification of Ф0.8-Ф4.0 mm.

[0035] The finished billet is peeled, polished, oiled, and then packaged separately. The packaging weight is 1-100 Kg to obtain the final aluminum alloy welding wire.

[0036] Compared with the prior art, the present invention has the following beneficial effects:

[0037] 1. The present invention conducts a modification design based on the Al-Mg-Si alloy system as the matrix to ensure the homogenization effect of the weld and the base metal after welding of the 6-series aluminum alloy: The welding of traditional 6-series aluminum alloys (Al-Mg-Si system) uses 4-series (Al-Si system) or 5-series (Al-Mg system) aluminum alloy welding wires. Due to the solid-liquid-solid state transformation between materials during welding and the extremely short change time, it is difficult for elements to diffuse for a long time and over a long distance. Further, during the cooling process after welding, the diffusion of elements in the solid state is more difficult than in the liquid state. Therefore, after welding the base metal with welding materials with a large composition difference, the composition, structure, and properties of the weld and the base metal are quite different, and it will further increase the recycling cost of the material. The Al-Mg-Si alloy welding wire provided by the present invention conducts a modification design based on the Al-Mg-Si alloy system as the matrix, so that the weld is also a 6-series aluminum alloy, which can solve the problem of non-homogenization between the weld and the base metal.

[0038] 2. The mass ratio of Mg to Si in the aluminum alloy welding wire of the present invention is 1-2:1, which can ensure the quantity of Mg2Si phase after welding of the welding material to meet the performance requirements:

[0039] In 6xxx series aluminum alloys, the main strengthening phase is the Mg2Si phase. To ensure that the strength of the material meets the requirements, it is necessary to first ensure that there is a sufficient number of Mg2Si phases inside the material. Since the relative atomic mass ratio of Mg and Si in the Mg2Si phase is Mg:Si = 1.73, theoretically, the mass ratio of Mg:Si should be controlled at around 1.73. However, in actual production, if elements such as Fe and Mn exist in the material, Si will be snatched, forming (Al,Fe,Mn,Si) phases, resulting in a reduction in the Si content available for forming Mg2Si phases and an excess of Mg elements. Consequently, the formed Mg2Si phases are reduced. When the Si in the material is in excess, the above situation can be avoided, and it can also reduce the adverse effects of some impurity elements on the material. Therefore, when only considering this situation, the Mg:Si mass ratio should be less than 1.73. During welding, the welding current can instantaneously raise the temperature of the solder and the melted part of the base material to several thousand degrees Celsius, and then rapidly cool and solidify. During this process, low melting point metals such as Mg are prone to volatilization, resulting in a lower Mg content in the post-weld material than in the original welding material. Due to the low Mg content, not enough Mg2Si phases can be formed, thereby causing the performance of the material to not meet the requirements. Therefore, when only considering this situation, the Mg:Si mass ratio should be greater than 1.73. When actually producing the solder, due to different requirements of customers for the performance and composition of the material, the contents of Mg2Si, impurities, and various trace elements will also be different. Therefore, it is necessary to flexibly adjust the contents and ratios of Mg and Si elements. Considering various factors comprehensively, the Mg:Si mass ratio of the present invention is 1 - 2:1, which can be used to meet the needs of various customers.

[0040] 3. By adding Zr and Ti elements, the present invention refines the grain size of the weld seam, inhibits the precipitation of low melting point second phases, and reduces the hot crack sensitivity of the 6xxx series aluminum alloy weld seam during welding:

[0041] The added Zr and Ti elements in the present invention will form several high-quality heterogeneous nucleation sites such as Al3Zr, Al3Ti, and Al3(Zr x , Ti 1-x ) in the melt. If B exists in the melt, heterogeneous nucleation sites such as TiB2 and ZrB2 will also be formed. These heterogeneous nucleation sites promote the refinement of grains in the weld seam structure and cause part of the columnar crystal region in the as-cast structure to transform into an equiaxed crystal region (as shown in Figure 1 ), optimize the co-deformation effect between the weld seam grains during solidification, and inhibit the penetration of Mg and Si elements between grain boundaries during material solidification, reducing the precipitation of low melting point phases at grain boundaries. The refinement of the material grains and the less precipitation of low melting point second phases at grain boundaries together reduce the hot crack sensitivity of the material during welding, and the weld seam surface is beautiful and crack-free (as shown in Figure 2 ).

[0042] However, when the addition amount of Ti and Zr elements in the material reaches a certain threshold, the grain size of the material changes slowly with the increase of the addition amount of Ti and Zr elements, and in particular, the excessive Ti element in the aluminum melt is easy to form a complex (Al, Fe, Mn, Cr, Ti) phase with elements such as Fe, Mn, and Cr. The phase is large in size and easy to aggregate. It is difficult to dissolve back into the matrix at high temperature, which has an adverse effect on the plastic processing process of the subsequent material. At the same time, the welding material has a genetic effect as the raw material during welding. When there are more such phases in the welding material, part of the phase will be retained in the weld, thereby deteriorating the material performance after welding. Therefore, in the present invention, Zr is used as the main refining element, Ti is used as an auxiliary refining element, and the addition amount of Zr and Ti elements is controlled to optimize the performance level of the material.

[0043] 4. The present invention optimizes the mechanical properties and high temperature thermal stability of the material by adding a certain amount of trace elements W1, namely one or more of Cu, Mn, Cr, B, and Sr, together with Ti and Zr:

[0044] The Cu element has the effect of supplementing solid solution strengthening in Al-Mg-Si alloys. Cu exists in the Al alloy matrix in the form of GP zone (Cu atom aggregation zone in the matrix). The GP zone is coherent with the matrix, which can improve the strength of the material in the non-aging state. At the same time, Cu can also improve the strength of the material during the aging process. Cu in some GP zones precipitates to form semi-coherent and incoherent phases with the matrix, such as Al2Cu phase, thereby improving the aging strength of the material. At the same time, Cu can also increase the dispersion of the precipitated phase of the material. Cu can form AlMgSi(Cu) phase together with Mg and Si to improve the precipitation strengthening effect of the material. In addition, Cu will also generate Fe-rich refractory phases such as Al7Cu2Fe in Al alloys together with the impurity element Fe to improve the high-temperature thermal stability of the material.

[0045] Mn and Cr also have the effect of supplementing solid solution strengthening in Al-Mg-Si alloys, which can further enhance the mechanical properties of the material. In addition, Mn, Cr and other elements will react with impurity Fe in aluminum alloys to generate Fe-rich refractory phases such as Al6 (Fe, Mn, Cr), spheroidizing the original Fe-rich phase morphology, reducing the adverse effects of impurity element Fe on the material, and optimizing material performance.

[0046] B has the effect of refining and removing impurities in aluminum alloys. B easily forms borides with various transition elements such as Mn, V, Ti, etc. The formed borides have the effect of refining the material and can improve the high-temperature thermal stability of the material. At the same time, B element can be added to react with some unnecessary impurity elements during smelting. Due to the difference in density between the product and the aluminum liquid, it can be effectively removed by static treatment during smelting, thereby purifying the aluminum liquid and improving the elongation, electrical conductivity, thermal conductivity and other properties of the material.

[0047] Sr has an extremely strong modification effect on Si in aluminum alloys. In materials with high Si content, even a Sr content of only 0.005 wt% can have a certain effect. During the solidification stage of the material, Sr atoms will aggregate around the Si phase and hinder the continued growth of the Si phase at the interface between Si and Al. It can change the cross-sectional morphology of the Si structure from long needle-like or plate-like shapes dozens of micrometers long to fine granular shapes less than one micrometer, and can effectively improve the conductivity and elongation performance of aluminum alloys with higher Si content. In the Al-Mg-Si system, if a large amount of excess Si needs to be added to the material due to special requirements, the relevant properties of the material can be improved by adding a certain amount of Sr.

[0048] However, when elements such as Cu, Mn, Cr, B, and Sr are in excess, refractory large intermetallic compounds are likely to appear in the melting and casting process. Moreover, excessive Mn and Cr will also seize Ti in the melt to form refractory aggregation phases, affecting the refinement effect of Ti on the material. These large refractory intermetallic compounds and aggregation phases will reduce the subsequent processing performance and welding performance of the material.

[0049] 5. The Al-Mg-Si alloy wire of the present invention, as a filler raw material for welding, can be heat-treated after welding to improve the overall performance of the weld and further optimize the homogenization effect of the weld and the base material:

[0050] The alloy of the present invention contains a certain amount of Mg and Si elements at the same time. Mg2Si phase can be precipitated through heat treatment aging. At the same time, the addition of Zr among the main modification elements and Cu and Mn among the trace elements can further improve the aging strength of the material. Compared with traditional 4-series and 5-series welding wires, it has the advantage that it can be heat-treated and strengthened together with the 6-series base material after welding. In addition to improving the overall performance, it can also make the tissue types of the weld and the base material as close as possible (as shown in Figure 3 、 4 ).

[0051] 6. In the present invention, an appropriate amount of La or Ce elements can be selectively added to purify impurity elements and refine the structure of the alloy system:

[0052] La and Ce, as the two most common elements in the lanthanide rare earths, have good impurity removal effects and can improve the conductivity of the material. When the generated compounds are at the grain boundaries of the material, they also have a certain refinement effect on the material and can improve the elongation of the material.

[0053] 7. The Al-Mg-Si welding wire of the present invention is more economical in cost compared with similar products, which is conducive to the production and application of the products:

[0054] The main modification elements are Ti and Zr. Compared with some other similar products that add expensive rare earths (such as Er, Y, etc.) or expensive metal elements (Sc, Ag, etc.), it makes the manufacturing cost lower while ensuring the performance.

[0055] 8. The preparation method of the aluminum alloy welding wire of the present invention includes: melting and casting to obtain an ingot, hot extrusion to obtain a mother rod, plastic processing to obtain a bus bar, obtaining a finished billet after annealing and re-plastic processing, and then obtaining the final aluminum alloy welding wire after peeling and packaging. By limiting the component elements and their contents, and then cooperating with an appropriate preparation method, an aluminum alloy welding wire with excellent mechanical properties and welding performance is finally obtained. Brief Description of the Drawings

[0056] Figure 1 Metallographic phase of the anodic film covering of the as-cast structure of the Al-Mg-Si-Zr-Ti alloy in Example 1 at 100 times magnification;

[0057] Figure 2 Macrograph of the weld bead surface after welding the 6061-T6 plate with the welding wire in Example 1;

[0058] Figure 3 Microstructure metallographic diagrams of different regions of the welded joint in the T6 state after welding the 6061-T6 plate with the welding wire in Example 1, where Figure 3 (A) in it is the metallographic phase diagram of the weld at 100 times magnification, Figure 3 (B) in it is the metallographic phase diagram of the fusion zone at 100 times magnification;

[0059] Figure 4 Hardness test results of the welded joint in different heat treatment states after welding the 6061-T6 plate with the welding wire in Example 1. Detailed Embodiments

[0060] The technical solutions of the present invention will be further described and illustrated below through specific embodiments and drawings. It should be understood that the specific embodiments described herein are only used to help understand the present invention and are not used for specific limitations of the present invention. And the drawings used in this article are only for better explaining the content disclosed by the present invention and do not have a limiting effect on the protection scope. If there is no special description, the raw materials used in the embodiments of the present invention are all common raw materials in the art, and the methods used in the embodiments are all conventional methods in the art.

[0061] Example 1

[0062] The chemical composition of an Al-Mg-Si alloy welding wire according to the present invention is by mass percentage: Mg: 0.54%, Si: 0.52%, Zr: 0.23%, Ti: 0.02%, Cu: 0.05%, Mn: 0.04%, Cr: 0.007%, B: 0.005%, Sr: 0.006%, La: 0.001%, Ce: 0.10%, the total sum of other impurity elements is less than 0.5%, and the balance is Al.

[0063] The Al-Mg-Si alloy welding wire is prepared by using industrial pure aluminum and intermediate alloys composed of corresponding elements and aluminum according to the following process:

[0064] (1) According to the weight percentage of the target composition, put industrial pure aluminum and Al-Mg, Al-Si, Al-Cu, Al-Mn, Al-Zr, Al-Ti, Al-B, Al-Ce intermediate alloys into a crucible for aluminum alloy melting and casting in proportion, raise the temperature to melt the pure aluminum and the intermediate alloys, the melting temperature is 820 °C, after all are melted, put in a chloride salt refining agent (the chloride salt refining agent used in this article is DCR-07A of Shenzhen Dingcheng Foundry Lubricating Materials, the same below), conduct slag removal treatment on the melt, then introduce high-purity argon gas to purge the aluminum liquid for 10 min, then let it stand for 15 min, conduct on-line detection and adjustment of the composition during the process, after the melt purging is completed, skim off the surface scum, cool the melt to 700 °C and then conduct casting to obtain an aluminum alloy ingot.

[0065] (2) After subjecting the aluminum alloy ingot to homogenization annealing treatment at 500 °C for 24 h, then prepare it into a cylindrical extrusion ingot through machining, and conduct extrusion of wire blanks on the extrusion ingot to obtain an aluminum alloy mother rod with a diameter of Ф12.0 mm, the temperature of the extrusion die and the extrusion cylinder is 380 °C, and the extrusion temperature is 420 °C.

[0066] (3) Conduct plastic processing on the aluminum alloy mother rod processed in step (2) to obtain a bus bar with a specification of Ф4.2 mm.

[0067] (4) Soften and anneal the aluminum alloy bus bar processed in step (3), and the annealing process is 380 °C / 4 h.

[0068] (5) Conduct plastic processing on the annealed bus bar processed in step (4), and the final finished product blank has a specification of Ф3.22 mm.

[0069] (6) After subjecting the finished product blank to peeling, polishing, and coating treatment, obtain a finished welding wire with a bright surface and a diameter of Φ3.2 mm; then conduct packaging on the finished welding wire, and the packaging weight is 5 Kg.

[0070] Figure 1The 100x metallographic structure of the anodic film of the as-cast structure of Al-Mg-Si-Zr-Ti in Example 1 was obtained by sampling the ingot sample and performing anodic film polarization metallographic testing. In the as-cast structure, part of the columnar crystal region was transformed into an equiaxed crystal region.

[0071] Example 2

[0072] The chemical composition of an Al-Mg-Si alloy welding wire of the present invention is by mass percentage: Mg: 0.83%, Si: 0.55%, Zr: 0.22%, Ti: 0.02%, Cu: 0.05%, Mn: 0.04%, Cr: 0.007%, B: 0.005%, Sr: 0.006%, La: 0.10%, Ce: 0.001%, and the total sum of other impurity elements is less than 0.5%, with the balance being Al.

[0073] The Al-Mg-Si alloy welding wire was prepared by using industrial pure aluminum and master alloys composed of corresponding elements and aluminum according to the following process:

[0074] (1) According to the weight percentage of the target composition, industrial pure aluminum and Al-Mg, Al-Si, Al-Cu, Al-Mn, Al-Zr, Al-Ti, Al-B, Al-La master alloys were proportionally put into a crucible for aluminum alloy melting and casting. The temperature was raised to melt the pure aluminum and master alloys. The melting temperature was 820°C. After all were melted, a chloride salt refining agent was added for slag removal treatment of the melt. Subsequently, high-purity argon gas was introduced for purging the aluminum liquid for 10 minutes, and then it was left standing for 15 minutes. During the process, on-line detection and adjustment of the composition were carried out. After the melt purging was completed, the surface scum was removed, and the melt was cooled to 700°C and then cast to obtain an aluminum alloy ingot.

[0075] (2) After the aluminum alloy ingot was subjected to homogenization annealing treatment at 500°C for 24 hours, it was further processed by machining to prepare a cylindrical extrusion ingot. The extrusion ingot was extruded into an aluminum alloy mother rod with a diameter of Ф10.0 mm. The temperature of the extrusion die and the extrusion cylinder was 400°C, and the extrusion temperature was 440°C.

[0076] (3) The aluminum alloy mother rod processed in step (2) was subjected to plastic processing to obtain a bus bar with a specification of Ф2.5 mm.

[0077] (4) The aluminum alloy bus bar processed in step (3) was softened and annealed, and the annealing process was 380°C / 4 h.

[0078] (5) The annealed bus bar processed in step (4) was subjected to plastic processing, and the final finished product blank had a specification of Ф1.62 mm.

[0079] (6) After subjecting the finished billet to peeling, polishing, and coating treatments, a finished welding wire with a diameter of Φ1.6 mm and a bright surface is obtained; then the finished welding wire is packaged, with a packaging weight of 9 Kg.

[0080] Example 3

[0081] The chemical composition of an Al-Mg-Si alloy welding wire of the present invention is by mass percentage: Mg: 1.21%, Si: 0.83%, Zr: 0.20%, Ti: 0.02%, Cu: 0.04%, Mn: 0.04%, Cr: 0.02%, B: 0.006%, Sr: 0.006%, La: 0.06%, Ce: 0.04%, and the total sum of other impurity elements is less than 0.5%, with the balance being Al.

[0082] An Al-Mg-Si alloy welding wire is prepared by using industrial pure aluminum and intermediate alloys composed of corresponding elements and aluminum according to the following process:

[0083] (1) According to the weight percentage of the target composition, industrial pure aluminum and Al-Mg, Al-Si, Al-Cu, Al-Mn, Al-Cr, Al-Zr, Al-Ti, Al-B, Al-La, and Al-Ce intermediate alloys are proportionally charged into a crucible for melting aluminum alloy castings. The temperature is raised to melt the pure aluminum and the intermediate alloys. The melting temperature is 820 °C. After all are melted, a chloride salt refining agent is added for slag removal treatment of the melt. Subsequently, high-purity argon gas is introduced for purging the aluminum liquid for 10 min, and then it is left standing for 15 min. During the process, on-line detection and adjustment of the composition are carried out. After the melt purging is completed, the surface scum is skimmed off, and the melt is cooled to 700 °C and then cast to obtain an aluminum alloy ingot.

[0084] (2) After subjecting the aluminum alloy ingot to homogenization annealing treatment at 500 °C for 24 h, it is then machined mechanically into a cylindrical extrusion ingot, and the extrusion ingot is extruded to prepare an aluminum alloy mother rod with a diameter of Ф10.0 mm. The temperature of the extrusion die and the extrusion cylinder is 400 °C, and the extrusion temperature is 440 °C.

[0085] (3) The aluminum alloy mother rod processed in step (2) is subjected to plastic processing to obtain a bus bar with a specification of Ф2.5 mm.

[0086] (4) The aluminum alloy bus bar processed in step (3) is softened and annealed, and the annealing process is 380 °C / 4 h.

[0087] (5) The annealed bus bar processed in step (4) is subjected to plastic processing, and the final specification of the finished billet is Ф1.22 mm.

[0088] (6) After subjecting the finished billet to peeling, polishing, and coating treatments, a finished welding wire with a diameter of Φ1.2 mm and a bright surface is obtained; then the finished welding wire is packaged, with the packaged weight being 7 Kg.

[0089] Example 4

[0090] The chemical composition of an Al-Mg-Si alloy welding wire of the present invention is by mass percentage: Mg: 1.34%, Si: 0.73%, Zr: 0.21%, Ti: 0.02%, Cu: 0.05%, Mn: 0.04%, Cr: 0.02%, B: 0.006%, Sr: 0.006%, La: 0.04%, Ce: 0.06%, and the total sum of other impurity elements is less than 0.5%, with the balance being Al.

[0091] The Al-Mg-Si alloy welding wire is prepared by using industrial pure aluminum and master alloys composed of corresponding elements and aluminum according to the following process:

[0092] (1) According to the weight percentages of the target components, industrial pure aluminum and Al-Mg, Al-Si, Al-Cu, Al-Mn, Al-Cr, Al-Zr, Al-Ti, Al-B, Al-La, and Al-Ce master alloys are proportionally charged into a crucible for melting aluminum alloys. The temperature is raised to melt the pure aluminum and the master alloys. The melting temperature is 820 °C. After all are melted, a chloride salt refining agent is added for slag removal treatment of the melt. Subsequently, high-purity argon gas is introduced for purging the aluminum liquid for 10 min, and then it is left standing for 15 min. During the process, on-line detection and adjustment of the composition are carried out. After the melt purging is completed, the surface scum is removed, and the melt is cooled to 700 °C and then cast to obtain an aluminum alloy ingot.

[0093] (2) After subjecting the aluminum alloy ingot to homogenization annealing treatment at 500 °C for 24 h, it is then machined mechanically into a cylindrical extrusion ingot. The extrusion ingot is extruded to prepare an aluminum alloy mother rod with a diameter of Ф10.0 mm. The temperature of the extrusion die and the extrusion cylinder is 400 °C, and the extrusion temperature is 440 °C.

[0094] (3) The aluminum alloy mother rod processed in step (2) is subjected to shaping processing to obtain a bus bar with a specification of Ф2.5 mm.

[0095] (4) The aluminum alloy bus bar processed in step (3) is softened and annealed, and the annealing process is 380 °C / 4 h.

[0096] (5) The annealed bus bar processed in step (4) is subjected to plastic processing, and the final finished billet specification is Ф1.22 mm.

[0097] (6) After subjecting the finished billet to peeling, polishing, and coating treatments, a finished welding wire with a diameter of Φ1.2 mm and a bright surface is obtained; then the finished welding wire is packaged, with a packaging weight of 7 Kg.

[0098] Example 5

[0099] The chemical composition of an Al-Mg-Si alloy welding wire of the present invention is by mass percentage: Mg: 1.01%, Si: 0.96%, Zr: 0.20%, Ti: 0.02%, Cu: 0.04%, Mn: 0.04%, Cr: 0.009%, B: 0.006%, Sr: 0.02%, La: 0.02%, Ce: 0.01%, and the total sum of other impurity elements is less than 0.5%, with the balance being Al.

[0100] The Al-Mg-Si alloy welding wire is prepared by using industrial pure aluminum and intermediate alloys composed of corresponding elements and aluminum according to the following process:

[0101] (1) According to the weight percentages of the target components, industrial pure aluminum and Al-Mg, Al-Si, Al-Sr, Al-Cu, Al-Mn, Al-Zr, Al-Ti, Al-B, Al-La, and Al-Ce intermediate alloys are proportionally charged into a crucible for aluminum alloy melting and casting, the temperature is raised to melt the pure aluminum and the intermediate alloys, the melting temperature is 820 °C, after all are melted, a chloride salt refining agent is added for slag removal treatment of the melt, then high-purity argon gas is introduced for purging the aluminum liquid for 10 min, then it is left standing for 15 min, on-line composition detection and adjustment are carried out during the process, after the melt purging is completed, the surface floating slag is removed, and the melt is cooled to 700 °C and then cast to obtain an aluminum alloy ingot.

[0102] (2) After subjecting the aluminum alloy ingot to homogenization annealing treatment at 500 °C for 24 h, it is then machined mechanically to prepare a cylindrical extrusion ingot, and the extrusion ingot is extruded to prepare an aluminum alloy mother rod with a diameter of Ф10.0 mm, the temperature of the extrusion die and the extrusion cylinder is 400 °C, and the extrusion temperature is 440 °C.

[0103] (3) The aluminum alloy mother rod processed in step (2) is subjected to shaping processing to obtain a bus bar with a specification of Ф2.5 mm.

[0104] (4) The aluminum alloy bus bar after step (3) is softened and annealed, and the annealing process is 380 °C / 4 h.

[0105] (5) The annealed bus bar processed in step (4) is subjected to plastic processing, and the final finished billet specification is Ф1.22 mm.

[0106] (6) After subjecting the finished billet to peeling, polishing, and coating treatments, a finished welding wire with a diameter of Φ1.2 mm and a bright surface is obtained; then the finished welding wire is packaged, with a packaging weight of 7 Kg.

[0107] Example 6

[0108] The chemical composition of an Al-Mg-Si alloy welding wire of the present invention is, by mass percentage: Mg: 0.55%, Si: 0.47%, Zr: 0.24%, Ti: 0.02%, Cu: 0.05%, Mn: 0.04%, Cr: 0.007%, B: 0.005%, Sr: 0.007%, La: 0.03%, Ce: 0.02%, and the total sum of other impurity elements is less than 0.5%, with the balance being Al.

[0109] The Al-Mg-Si alloy welding wire is prepared by using industrial pure aluminum and master alloys composed of corresponding elements and aluminum according to the following process:

[0110] (1) According to the weight percentages of the target components, industrial pure aluminum and Al-Mg, Al-Si, Al-Cu, Al-Mn, Al-Zr, Al-Ti, Al-B, Al-La, and Al-Ce master alloys are proportionally charged into a crucible for aluminum alloy melting and casting. The temperature is raised to melt the pure aluminum and the master alloys. The melting temperature is 800 °C. After all are melted, a chloride salt refining agent is added for slag removal treatment of the melt. Subsequently, high-purity argon gas is introduced for purging the aluminum liquid for 5 minutes, and then it is left standing for 15 minutes. During the process, on-line component detection and adjustment are carried out. After the melt purging is completed, the surface scum is skimmed off, and the melt is cooled to 720 °C and then cast to obtain an aluminum alloy ingot.

[0111] (2) After subjecting the aluminum alloy ingot to homogenization annealing treatment at 540 °C for 16 h, it is then machined mechanically to prepare a cylindrical extrusion ingot. The extrusion ingot is extruded to prepare an aluminum alloy mother rod with a diameter of Ф7.5 mm. The temperature of the extrusion die and the extrusion cylinder is 400 °C, and the extrusion temperature is 450 °C.

[0112] (3) The aluminum alloy mother rod processed in step (2) is subjected to plastic processing to obtain a bus bar with a specification of Ф2.5 mm.

[0113] (4) The aluminum alloy bus bar processed in step (3) is softened and annealed, and the annealing process is 380 °C / 4 h.

[0114] (5) The annealed bus bar processed in step (4) is subjected to plastic processing, and the final specification of the finished billet is Ф1.22 mm.

[0115] (6) After subjecting the finished billet to peeling, polishing, and coating treatments, a finished welding wire with a diameter of Φ1.2 mm and a bright surface is obtained; then the finished welding wire is packaged, with a packaging weight of 40 Kg.

[0116] Example 7

[0117] The chemical composition of an Al-Mg-Si alloy welding wire of the present invention is, by mass percentage: Mg: 0.67%, Si: 0.59%, Zr: 0.27%, Ti: 0.07%, Cu: 0.09%, Mn: 0.05%, Cr: 0.005%, B: 0.008%, Sr: 0.006%, La: 0.002%, Ce: 0.001%, and the total sum of other impurity elements is less than 0.5%, with the balance being Al.

[0118] The Al-Mg-Si alloy welding wire is prepared by using industrial pure aluminum and master alloys composed of corresponding elements and aluminum according to the following process:

[0119] (1) According to the weight percentages of the target components, industrial pure aluminum and Al-Mg, Al-Si, Al-Cu, Al-Mn, Al-Zr, and Al-5Ti-B master alloys are proportionally charged into a crucible for aluminum alloy melting and casting, the temperature is raised to melt the pure aluminum and the master alloys, the melting temperature is 820 °C, after all are melted, a chloride salt refining agent is added for slag removal treatment of the melt, then high-purity argon gas is introduced for purging the aluminum liquid for 5 min, then it is left standing for 15 min, in-process on-line composition detection and adjustment are carried out, after the melt purging is completed, the surface floating slag is removed, the melt is cooled to 720 °C and then cast to obtain an aluminum alloy ingot.

[0120] (2) After subjecting the aluminum alloy ingot to homogenization annealing treatment at 540 °C for 16 h, it is then machined into a cylindrical extrusion ingot through mechanical processing, and the aluminum alloy mother rod with a diameter of Ф12.0 mm is prepared by extruding the extrusion ingot, the temperature of the extrusion die and the extrusion cylinder is 400 °C, and the extrusion temperature is 470 °C.

[0121] (3) The aluminum alloy mother rod processed in step (2) is subjected to shaping processing to obtain a bus bar with a specification of Ф4.2 mm.

[0122] (4) The aluminum alloy bus bar processed in step (3) is softened and annealed, and the annealing process is 380 °C for 4 h.

[0123] (5) The annealed bus bar processed in step (4) is subjected to plastic processing, and the final finished billet specification is Ф3.22 mm.

[0124] (6) After subjecting the welding wire finished billet to peeling, polishing, and coating treatments, a finished welding wire with a diameter of Φ3.2 mm and a bright surface is obtained; then the finished welding wire is packaged, with a packaging weight of 5 Kg.

[0125] Example 8

[0126] The chemical composition of an Al-Mg-Si alloy welding wire of the present invention is by mass percentage: Mg: 0.68%, Si: 0.58%, Zr: 0.25%, Ti: 0.095%, Cu: 0.07%, Mn: 0.04%, Cr: 0.008%, B: 0.009%, Sr: 0.006%, La: 0.07%, Ce: 0.04%; the total sum of other impurity elements is less than 0.5%, and the balance is Al.

[0127] The Al-Mg-Si alloy welding wire is prepared by the following process using industrial pure aluminum and master alloys composed of corresponding elements and aluminum:

[0128] (1) According to the weight percentage of the target composition, put industrial pure aluminum and Al-Mg, Al-Si, Al-Cu, Al-Mn, Al-Zr, Al-5Ti-B, Al-La, Al-Ce master alloys into a crucible for aluminum alloy melting and casting in proportion, raise the temperature to melt the pure aluminum and master alloys, the melting temperature is 820 °C. After all are melted, put in a chloride salt refining agent for slag removal treatment of the melt. Subsequently, introduce high-purity argon for purging the aluminum liquid for 5 minutes, then let it stand for 10 minutes. During the process, on-line detection and adjustment of the composition are carried out. After the melt purging is completed, skim off the surface scum, cool the melt to 720 °C and then carry out casting to obtain an aluminum alloy ingot.

[0129] (2) After subjecting the aluminum alloy ingot to homogenization annealing treatment at 540 °C for 16 h, then prepare it into a cylindrical extrusion ingot through machining. Extrude the extrusion ingot to obtain an aluminum alloy mother rod with a diameter of Ф12.0 mm. The temperature of the extrusion die and the extrusion cylinder is 400 °C, and the extrusion temperature is 470 °C.

[0130] (3) Carry out cold plastic processing on the aluminum alloy mother rod processed in step (2) and draw it to obtain a specification of Ф2.5 mm.

[0131] (4) Soften and anneal the aluminum alloy bus bar processed in step (3), and the annealing process is 380 °C / 4 h.

[0132] (5) Carry out plastic processing on the annealed bus bar processed in step (4), and the final finished product blank specification is Ф1.62 mm.

[0133] (6) After subjecting the finished product blank of the welding wire to peeling, polishing, and coating treatments, obtain a finished welding wire with a bright surface of Ф1.6 mm; then carry out packaging on the finished welding wire, and the packaging weight is 7 Kg.

[0134] Example 9

[0135] The chemical composition of an Al-Mg-Si alloy welding wire of the present invention is by mass percentage: Mg: 0.57%, Si: 0.51%, Zr: 0.22%, Ti: 0.007%, Cu: 0.03%, Mn: 0.006%, Cr: 0.006%, B: 0.005%, Sr: 0.006%, La: 0.06%, Ce: 0.002%, the total sum of other impurity elements is less than 0.5%, and the balance is Al.

[0136] The Al-Mg-Si alloy welding wire is prepared by the following process using industrial pure aluminum and master alloys composed of corresponding elements and aluminum:

[0137] (1) According to the weight percentage of the target composition, put industrial pure aluminum and Al-Mg, Al-Si, Al-Cu, Al-Mn, Al-Zr, Al-Ti, Al-B, Al-La master alloys into a crucible for aluminum alloy melting and casting in proportion, raise the temperature to melt the pure aluminum and master alloys, the melting temperature is 820 °C, after all are melted, put in a chloride salt refining agent to carry out slag removal treatment of the melt, then introduce high-purity argon for purging the aluminum liquid for 10 min, then let it stand for 15 min, conduct on-line detection and adjustment of the composition during the process, after the melt purging is completed, skim off the surface scum, cool the melt to 700 °C and then carry out casting to obtain an aluminum alloy ingot.

[0138] (2) After carrying out homogenization annealing treatment on the aluminum alloy ingot at 500 °C / 24 h, then prepare it into a cylindrical extrusion ingot through machining, and carry out extrusion of wire blanks on the extrusion ingot to obtain an aluminum alloy mother rod with a diameter of Ф12.0 mm, the temperature of the extrusion die and the extrusion cylinder is 380 °C, and the extrusion temperature is 420 °C.

[0139] (3) Carry out plastic processing on the aluminum alloy mother rod processed in step (2) to obtain a bus bar with a specification of Ф4.2 mm.

[0140] (4) Soften and anneal the aluminum alloy bus bar processed in step (3), and the annealing process is 380 °C / 4 h.

[0141] (5) Carry out plastic processing on the annealed bus bar processed in step (4), and the final finished product blank has a specification of Ф3.22 mm.

[0142] (6) After carrying out peeling, polishing, and coating treatment on the finished product blank, obtain a finished welding wire with a bright surface and a diameter of Φ3.2 mm; then carry out packaging of the finished welding wire, and the packaging weight is 5 Kg.

[0143] Example 10

[0144] The chemical composition of an Al-Mg-Si alloy welding wire of the present invention is by mass percentage: Mg: 0.55%, Si: 0.52%, Zr: 0.21%, Ti: 0.007%, Cu: 0.03%, Mn: 0.007%, Cr: 0.005%, B: 0.006%, Sr: 0.006%, La: 0.002%, Ce: 0.05%, the total sum of other impurity elements is less than 0.5%, and the balance is Al.

[0145] The Al-Mg-Si alloy welding wire is prepared by the following process using industrial pure aluminum and master alloys composed of corresponding elements and aluminum:

[0146] (1) According to the weight percentages of the target components, put industrial pure aluminum and master alloys of Al-Mg, Al-Si, Al-Cu, Al-Mn, Al-Zr, Al-Ti, Al-B, and Al-Ce into a crucible for aluminum alloy melting and casting in proportion, raise the temperature to melt the pure aluminum and master alloys, the melting temperature is 820 °C. After all are melted, add a chloride salt refining agent to conduct slag removal treatment on the melt. Subsequently, introduce high-purity argon gas to purge the aluminum liquid for 10 min, then let it stand for 15 min. During the process, conduct on-line composition detection and adjustment. After the melt purging is completed, skim off the surface scum, cool the melt to 700 °C and then conduct casting to obtain an aluminum alloy ingot.

[0147] (2) After subjecting the aluminum alloy ingot to homogenization annealing treatment at 500 °C for 24 h, then prepare it into a cylindrical extrusion ingot through machining. Conduct extrusion of wire blanks on the extrusion ingot to obtain an aluminum alloy mother rod with a diameter of Ф12.0 mm. The temperature of the extrusion die and the extrusion cylinder is 380 °C, and the extrusion temperature is 420 °C.

[0148] (3) Conduct plastic processing on the aluminum alloy mother rod obtained in step (2) to obtain a specification of Ф4.2 mm.

[0149] (4) Soften and anneal the aluminum alloy bus bar obtained in step (3), and the annealing process is 380 °C / 4 h.

[0150] (5) Conduct plastic processing on the annealed bus bar processed in step (4), and the final finished product blank has a specification of Ф3.22 mm.

[0151] (6) After subjecting the finished product blank to peeling, polishing, and coating treatments, obtain a finished welding wire with a bright surface of Ф3.2 mm; then conduct packaging on the finished welding wire, and the packaging weight is 5 Kg.

[0152] Example 11

[0153] The chemical composition of an Al-Mg-Si alloy welding wire of the present invention is by mass percentage: Mg: 0.57%, Si: 0.54%, Zr: 0.21%, Ti: 0.005%, Cu: 0.03%, Mn: 0.006%, Cr: 0.007%, B: 0.006%, Sr: 0.005%, Ce: 0.08%, La: 0.05%, the total sum of other impurity elements is less than 0.5%, and the balance is Al.

[0154] The Al-Mg-Si alloy welding wire is prepared by using industrial pure aluminum and master alloys composed of corresponding elements and aluminum according to the following process:

[0155] (1) According to the weight percentages of the target components, put industrial pure aluminum and Al-Mg, Al-Si, Al-Cu, Al-Mn, Al-Zr, Al-Ti, Al-B, Al-(La,Ce) master alloys into a crucible for aluminum alloy melting and casting in proportion, raise the temperature to melt the pure aluminum and master alloys, the melting temperature is 820 °C. After all are melted, put in a chloride salt refining agent to perform slag removal treatment on the melt. Subsequently, introduce high-purity argon gas to purge the aluminum liquid for 10 min, then let it stand for 15 min. During the process, conduct on-line detection and adjustment of the composition. After the melt purging is completed, skim off the surface scum, cool the melt to 700 °C and then perform casting to obtain an aluminum alloy ingot.

[0156] (2) After subjecting the aluminum alloy ingot to homogenization annealing treatment at 500 °C for 24 h, then prepare it into a cylindrical extrusion ingot through machining. Extrude the extrusion ingot to obtain an aluminum alloy mother rod with a diameter of Ф12.0 mm. The temperature of the extrusion die and the extrusion cylinder is 380 °C, and the extrusion temperature is 420 °C.

[0157] (3) Perform plastic processing on the aluminum alloy mother rod processed in step (2) to obtain a bus bar with a specification of Ф4.2 mm.

[0158] (4) Soften and anneal the aluminum alloy bus bar obtained in step (3), and the annealing process is 380 °C / 4 h.

[0159] (5) Perform plastic processing on the annealed bus bar processed in step (4), and the final finished product blank has a specification of Ф3.22 mm.

[0160] (6) After subjecting the finished product blank to peeling, polishing, and coating treatments, obtain a finished welding wire with a bright surface and a diameter of Φ3.2 mm; then package the finished welding wire, and the packaging weight is 5 Kg.

[0161] Comparative Example 1

[0162] The difference between Comparative Example 1 and Example 4 is that the chemical composition of the alloy wire in Comparative Example 1 is by mass percentage: Mg: 0.72%, Si: 1.36%, Zr: 0.22%, Ti: 0.02%, Cu: 0.06%, Mn: 0.04%, Cr: 0.02%, B: 0.008%, Sr: 0.006%, La: 0.04%, Ce: 0.05%, the total sum of other impurity elements is less than 0.5%, and the balance is Al. The preparation method is the same as that of Example 4.

[0163] Comparative Example 2

[0164] The difference between Comparative Example 2 and Example 4 is that the chemical composition of the alloy wire in Comparative Example 2 is by mass percentage: Mg: 1.48%, Si: 0.59%, Zr: 0.22%, Ti: 0.02%, Cu: 0.05%, Mn: 0.05%, Cr: 0.02%, B: 0.007%, Sr: 0.007%, La: 0.04%, Ce: 0.06%, the total sum of other impurity elements is less than 0.5%, and the balance is Al. The preparation method is the same as that of Example 4.

[0165] Comparative Example 3

[0166] The difference between Comparative Example 3 and Example 2 is that the chemical composition of the alloy wire in Comparative Example 3 is by mass percentage: Mg: 1.0%, Si: 0.38%, Zr: 0.22%, Ti: 0.02%, Cu: 0.05%, Mn: 0.04%, Cr: 0.006%, B: 0.008%, Sr: 0.007%, La: 0.11%, Ce: 0.001%, the total sum of other impurity elements is less than 0.5%, and the balance is Al. The preparation method is the same as that of Example 2.

[0167] Comparative Example 4

[0168] The difference between Comparative Example 4 and Example 1 is that the chemical composition of the alloy wire in Comparative Example 4 is by mass percentage: Mg: 1.8%, Si: 1.6%, Zr: 0.22%, Ti: 0.02%, Cu: 0.05%, Mn: 0.05%, Cr: 0.007%, B: 0.005%, Sr: 0.008%, La: 0.001%, Ce: 0.09%, the total sum of other impurity elements is less than 0.5%, and the balance is Al. The preparation method is the same as that of Example 1.

[0169] Comparative Example 5

[0170] The difference between Comparative Example 5 and Example 1 is that the chemical composition of the alloy wire in Comparative Example 5 is as follows by mass percentage: Mg: 0.3%, Si: 0.18%, Zr: 0.23%, Ti: 0.02%, Cu: 0.05%, Mn: 0.04%, Cr: 0.008%, B: 0.008%, Sr: 0.006%, La: 0.001%, Ce: 0.10%, the total sum of other impurity elements is less than 0.5%, and the balance is Al. The preparation method is the same as that of Example 1.

[0171] Comparative Example 6

[0172] The difference between Comparative Example 6 and Example 3 is that the chemical composition of the alloy wire in Comparative Example 6 is as follows by mass percentage: Mg: 1.22%, Si: 0.84%, Zr: 0.05%, Ti: 0.02%, Cu: 0.05%, Mn: 0.04%, Cr: 0.02%, B: 0.006%, Sr: 0.007%, La: 0.06%, Ce: 0.04%, the total sum of other impurity elements is less than 0.5%, and the balance is Al. The preparation method is the same as that of Example 3.

[0173] Comparative Example 7

[0174] The difference between Comparative Example 7 and Example 3 is that the chemical composition of the alloy wire in Comparative Example 7 is as follows by mass percentage: Mg: 1.19%, Si: 0.81%, Zr: 0.42%, Ti: 0.02%, Cu: 0.04%, Mn: 0.04%, Cr: 0.02%, B: 0.008%, Sr: 0.006%, La: 0.05%, Ce: 0.04%, the total sum of other impurity elements is less than 0.5%, and the balance is Al. The preparation method is the same as that of Example 3.

[0175] Comparative Example 8

[0176] The difference between Comparative Example 8 and Example 5 is that the chemical composition of the alloy wire in Comparative Example 8 is as follows by mass percentage: Mg: 1.04%, Si: 0.97%, Zr: 0.21%, Ti: 0.15%, Cu: 0.04%, Mn: 0.04%, Cr: 0.007%, B: 0.006%, Sr: 0.02%, La: 0.02%, Ce: 0.01%, the total sum of other impurity elements is less than 0.5%, and the balance is Al. The preparation method is the same as that of Example 5.

[0177] Comparative Example 9

[0178] The difference between Comparative Example 9 and Example 7 is that the chemical composition of the alloy wire in Comparative Example 9 is by mass percentage: Mg: 0.68%, Si: 0.57%, Zr: 0.27%, Ti: 0.06%, Cu: 0.16%, Mn: 0.05%, Cr: 0.005%, B: 0.007%, Sr: 0.006%, La: 0.002%, Ce: 0.001%, the total sum of other impurity elements is less than 0.5%, and the balance is Al. The preparation method is the same as that of Example 7.

[0179] Comparative Example 10

[0180] The difference between Comparative Example 10 and Example 7 is that the chemical composition of the alloy wire in Comparative Example 10 is by mass percentage: Mg: 0.70%, Si: 0.58%, Zr: 0.26%, Ti: 0.07%, Cu: 0.08%, Mn: 0.15%, Cr: 0.006%, B: 0.008%, Sr: 0.005%, La: 0.002%, Ce: 0.002%, the total sum of other impurity elements is less than 0.5%, and the balance is Al. The preparation method is the same as that of Example 7.

[0181] Comparative Example 11

[0182] The difference between Comparative Example 11 and Example 7 is that the chemical composition of the alloy wire in Comparative Example 11 is by mass percentage: Mg: 0.67%, Si: 0.58%, Zr: 0.27%, Ti: 0.08%, Cu: 0.09%, Mn: 0.05%, Cr: 0.17%, B: 0.009%, Sr: 0.006%, La: 0.002%, Ce: 0.001%, the total sum of other impurity elements is less than 0.5%, and the balance is Al. The preparation method is the same as that of Example 7.

[0183] Industrial pure aluminum and Al-Mg, Al-Si, Al-Cu, Al-Mn, Al-Cr, Al-Zr, Al-5Ti-B master alloys were put into a crucible for aluminum alloy melting and casting in proportion, and the others were the same as in Example 7.

[0184] Comparative Example 12

[0185] The difference between Comparative Example 12 and Example 7 is that the chemical composition of the alloy wire in Comparative Example 12 is by mass percentage: Mg: 0.66%, Si: 0.59%, Zr: 0.27%, Ti: 0.08%, Cu: 0.09%, Mn: 0.04%, Cr: 0.007%, B: 0.15%, Sr: 0.006%, La: 0.001%, Ce: 0.001%, the total sum of other impurity elements is less than 0.5%, and the balance is Al. The preparation method is the same as that of Example 7.

[0186] Comparative Example 13

[0187] The difference between Comparative Example 13 and Example 7 is that the chemical composition of the alloy wire in Comparative Example 13 by mass percentage is: Mg: 0.67%, Si: 0.55%, Zr: 0.25%, Ti: 0.08%, Cu: 0.07%, Mn: 0.05%, Cr: 0.005%, B: 0.008%, Sr: 0.16%, La: 0.002%, Ce: 0.001%, and the total sum of other impurity elements is less than 0.5%, with the balance being Al. The preparation method is the same as that of Example 7.

[0188] Industrial pure aluminum and Al-Mg, Al-Si, Al-Cu, Al-Mn, Al-Sr, Al-Zr, Al-5Ti-B master alloys were put into a crucible for aluminum alloy melting and casting in proportion, and the others were the same as in Example 7.

[0189] Comparative Example ER4043 is a φ3.2mm aluminum alloy straight bar product produced by Ningbo BoWei Alloy Precision Fine Wire Co., Ltd.

[0190] Table 1 Performance table of aluminum alloy welding wires prepared in examples and comparative examples

[0191]

[0192] TIG welding tests were carried out on the Al-Mg-Si welding wires prepared in the above examples and comparative examples. The base metal was 6061-T6 plate with a thickness of 6mm. The base metal was butted with a V-shaped groove. The mechanical properties of the welded joints after welding are shown in Table 2:

[0193] Table 2 Mechanical properties of welded joints after TIG welding 6061-T6 plates with the welding wires of examples and comparative examples

[0194]

[0195] Figure 2 It is the macroscopic state diagram of the weld bead surface after welding the 6061-T6 plate with the welding wire of Example 1. The weld surface is beautiful and crack-free. Figure 3 It is the metallographic diagram of the microstructure in different regions of the welded joint after welding the 6061-T6 plate with the welding wire of Example 1, where Figure 3 in (A) is the 100-fold metallographic diagram of the weld seam, Figure 3 in (B) is the 100-fold metallographic diagram of the fusion zone; it can be seen that the tissue types of the weld seam and the base metal are relatively close. Figure 4Test results of the hardness (HV5) of the welded joints of the wire for Example 1 after welding 6061-T6 plates under different heat treatment conditions; where the as-welded original state is the state without any heat treatment after welding, the as-welded aged state is the state after artificial aging heat treatment (205°C / 150 min, air cooling) after welding, and the as-welded T6 state refers to the state after a complete T6 heat treatment cycle (solution treatment: 540°C / 1 h, water cooling; aging: 205°C / 150 min, air cooling) after welding. From Figure 4 it can be seen that after this type of wire product is applied to 6061-T6 plates, different post-weld heat treatment processes can regulate and optimize the mechanical properties of the welded joint. In particular, by using post-weld T6 heat treatment, the overall hardness value of the welded joint can be significantly increased.

[0196] As can be seen from Table 1, the Al-Mg-Si alloy wire prepared by the present invention has good welding performance. When using the same welding method, compared with the traditional ER4043 wire selected for welding 6-series alloys, the strength of the welded joint after welding is better. Moreover, different addition amounts of Mg and Si and their mass ratios, as well as the variation of the addition amounts of different modification and microalloying elements within a certain range, can regulate the mechanical properties of the solder and its welded joint, and can meet the different requirements of customers for the composition and performance of the solder to a certain extent.

[0197] As can be seen from Comparative Examples 1-3, too high or too low mass ratio of Mg:Si has an adverse effect on the properties of the wire and the material after welding. Too much excess Mg hardens the material and harms the elongation of the material, while too much excess Si reduces the mechanical properties of the material. In Comparative Example 4, the contents of Mg and Si are on the high side, and the mechanical properties of the wire and the material after welding are high, but the elongation is on the low side; in Comparative Example 5, the contents of Mg and Si are on the low side, but the mechanical properties of the wire and the material after welding are too low to meet the general performance requirements.

[0198] In Comparative Example 6, the content of Zr is on the low side, the mechanical properties of the wire and the material after welding are on the low side, and welding hot cracks are likely to occur during actual operation, making welding difficult; in Comparative Example 7, the content of Zr is on the high side, the mechanical properties of the wire and the material after welding are improved, but the elongation is reduced significantly. In Comparative Example 8, the addition amount of Ti is too much, and the mechanical properties of the wire and the material after welding are improved, but the elongation is reduced significantly.

[0199] In Comparative Examples 9-13, the addition amounts of trace elements are too much. After the contents of Cu, Mn, Cr, and B are excessive, the mechanical properties of the wire and the material after welding are improved, but the elongation is reduced significantly. After the content of Sr is excessive, the mechanical properties of the wire and the material after welding are reduced, making it difficult to meet the general application requirements.

[0200] Aspects, embodiments, and features of the present invention should be considered illustrative in all respects and not limiting of the present invention, the scope of which is defined only by the claims. Without departing from the spirit and scope of the claimed invention, those skilled in the art will appreciate other embodiments, modifications, and uses.

[0201] In the preparation method of the present invention, the order of each step is not limited to the recited order. For those of ordinary skill in the art, without creative efforts, changes in the sequence of each step are also within the protection scope of the present invention. In addition, two or more steps or operations can be carried out simultaneously.

[0202] Finally, it should be noted that the specific embodiments described herein are only examples of the present invention and do not limit the implementation manner of the present invention. Those skilled in the technical field to which the present invention pertains can make various modifications or supplements to the described specific embodiments or use similar methods for substitution. It is not necessary and impossible to list all implementation manners here. And these obvious changes or variations derived from the essential spirit of the present invention still fall within the protection scope of the present invention. Interpreting them as any additional limitation is contrary to the spirit of the present invention.

Claims

1. An aluminum alloy welding wire for melting welding of 6 series aluminum alloys, characterized in that: The aluminum alloy welding wire comprises the following components in weight percentage: Mg: 0.4~1.01wt%; Si: 0.2~0.59wt%; Zr: 0.1~0.3wt%; Ti: 0.005~0.095wt%; La and / or Ce: 0.0005~0.1wt%; Cu: 0.005~0.1wt%; Mn: 0.005~0.1wt%; Cr: 0.005~0.02wt%; B: 0.005~0.009wt%; Sr: 0.005~0.1wt%; the content of any one of Li, Na, K, Ca, Rb, Cs is less than 0.001wt%; The mass ratio of Mg to Si is 1~2:1; The balance is aluminum and unavoidable impurity elements; The method for preparing the aluminum alloy welding wire for 6 series aluminum alloy melting welding comprises the following steps: (1) Mix the raw materials required for the aluminum alloy welding wire components and melt and cast to form an aluminum alloy ingot. The melting temperature is 780~850℃ and the casting temperature is 680~750℃; (2) The aluminum alloy ingot is first subjected to homogenization annealing treatment at a temperature of 500-570°C for a holding time of 12-24 hours, and then mechanically processed to obtain an extruded ingot with suitable specifications, and a mother rod is prepared by hot extrusion; (3) The mother bar is processed by the first plastic processing to obtain the mother bar; (4) The busbar undergoes intermediate annealing and then undergoes a second plastic processing to obtain the finished blank; (5) The finished blank is subjected to steps including peeling and packaging to obtain the final aluminum alloy welding wire.

2. The aluminum alloy welding wire for 6 series aluminum alloy melting welding according to claim 1, characterized in that: The Si is 0.47-0.58 wt %.

3. The aluminum alloy welding wire for 6 series aluminum alloy melting welding according to claim 1, characterized in that: The impurity elements include the following elements in weight percentage: Pb≤0.015wt%, Sb≤0.015wt%, Bi≤0.015wt%, Te≤0.015wt%, S≤0.015wt%, Fe≤0.40wt%, and Zn≤0.030wt%.

4. The method for preparing an aluminum alloy welding wire for 6 series aluminum alloy melting welding according to claim 1, characterized in that: The following steps are involved: (1) The raw materials required for the aluminum alloy welding wire components are mixed and melted to form an aluminum alloy ingot, with a melting temperature of 780~850℃ and a casting temperature of 680~750℃; (2) The aluminum alloy ingot is first subjected to homogenization annealing treatment at a temperature of 500-570°C for a holding time of 12-24 hours, and then mechanically processed to obtain an extruded ingot with suitable specifications, and a mother rod is prepared by hot extrusion; (3) The mother bar is processed by the first plastic processing to obtain the mother bar; (4) The busbar undergoes intermediate annealing and then undergoes a second plastic processing to obtain the finished blank; (5) The finished blank is subjected to steps including peeling and packaging to obtain the final aluminum alloy welding wire.

5. The preparation method according to claim 4, characterized in that: In step (2), during the hot extrusion process, the preheating temperature of the extrusion barrel and the extrusion die is 350-450°C, and the extrusion temperature is 380-480°C.

6. The preparation method according to claim 4, characterized in that: The specifications of the mother rod are Ф6~Ф13mm.

7. The preparation method according to claim 4, characterized in that: The specifications of the busbar are Ф2.0-Ф4.2mm.

8. The preparation method according to claim 4, characterized in that: The specifications of the finished billet are Ф0.8-Ф4.0mm.

9. The preparation method according to claim 4, characterized in that: The annealing temperature of the busbar for intermediate annealing is 340~400℃, and the holding time is 4~24h.

Images