Preparation method of aluminum alloy foaming welding wire

Abstract

The invention provides a preparation method of an aluminum alloy foaming welding wire, which belongs to the technical field of aluminum alloy welding wire production, and is characterized in that after an aluminum alloy matrix is smelted, a foaming stabilizer and a high-temperature foaming body are added step by step, and the porous welding wire is prepared through the processes of stirring and mixing, rapid cooling and casting, homogenizing annealing, multi-pass extrusion, drawing and the like. By means of the technical scheme, rapid filling and connection of the weld joint area after welding of the aluminum alloy material can be achieved, and the weld joint filling area presents a typical porous morphology; direct welding of the light porous aluminum alloy material is achieved, solidification of a weld joint area is avoided, and lightweight design is facilitated; welding foaming filling of a metal component cavity is achieved, due to foaming of a molten pool, the cavity filling efficiency can be greatly improved, and the formed metal component is endowed with the functional characteristics of damping vibration attenuation and the like; the porous aluminum alloy additive manufacturing welding wire can be used as an additive manufacturing welding wire and can be directly used for additive preparation forming of porous aluminum alloy materials.

Description

Technical Field

[0001] This invention relates to the field of aluminum alloy welding technology, and more particularly to a method for preparing aluminum alloy foamed welding wire. Background Technology

[0002] With the high-quality development of aerospace, rail transportation, and new energy vehicles, aluminum alloys have become the preferred material in modern industry due to their excellent specific strength, corrosion resistance, and ease of processing. Welding, as the core process for forming aluminum alloy parts, directly affects the service performance and safety reliability of the products. Fusion welding is currently the main process for aluminum alloy welding due to its economy and efficiency. It is a welding process that uses heat sources such as electric arcs, lasers, and electron beams to melt metal materials such as welding rods or welding wires to fill the weld seam and achieve metallurgical bonding of aluminum alloys.

[0003] Welding wire is an indispensable material for aluminum alloy fusion welding. However, due to the constraints of welding technology and conditions, traditional welding wire has several problems that urgently need to be solved in the welding process: First, traditional welding wire requires multiple welding passes for wide welds, resulting in low welding efficiency, large structural deformation, and a high tendency for coarsening of the base metal grains. Second, the welds formed by traditional welding wire are solid welds with a density close to that of aluminum alloys, which is not conducive to the lightweight design of parts under specific working conditions, especially for connecting aluminum alloy plates or structures with special functional designs such as lattice structures or porous features. Third, when traditional welding wire is used in arc additive manufacturing, the lightweight design and functional control of the part structure can only be achieved through structural optimization and adjustment. It cannot directly utilize the inherent properties of the welding wire metal to achieve functional characteristics such as weld damping, vibration reduction, sound insulation, and electromagnetic shielding.

[0004] Therefore, there is an urgent need to develop a special aluminum alloy foamed welding wire that can achieve foaming and filling during the fusion welding process, effectively solving the welding problems of lightweight lattice structures or porous aluminum alloy structural components. The newly developed aluminum alloy foamed welding wire must meet the requirements of low price and large-scale industrial production. Summary of the Invention

[0005] To overcome the shortcomings of existing technologies, this invention provides a method for preparing aluminum alloy foamed welding wire.

[0006] This invention is achieved through the following technical solution: a method for preparing aluminum alloy foamed welding wire, comprising the following steps: Step (1) Aluminum molten metal smelting: Add the aluminum alloy matrix with the preset chemical composition into the smelting furnace, heat and melt it. After all the furnace charge has melted, stir and remove the slag. Step (2) Adding foaming stabilizer: Transfer the molten aluminum alloy to the tundish and adjust the temperature of the molten aluminum alloy to 1.1 ~ 1.2 T. 熔Add a foaming stabilizer to the molten aluminum alloy and perform a first stirring and mixing process for 3 to 10 minutes; T 熔 This refers to the melting point temperature of the aluminum alloy matrix. Step (3) Add high-temperature foaming material: Adjust the temperature of the aluminum alloy melt to T 熔 ~ 1.1 T 熔 The high-temperature foam is added to the aluminum alloy melt and then stirred and mixed for a second time for 0.5 to 4 minutes. Step (4) Rapid cooling: After the second stirring and mixing is completed, the aluminum alloy melt in the tundish is poured into the metal mold, and cooling water is passed through to cool the mold to form a welding wire rod billet; Step (5) Homogenization annealing: Heat the welding wire rod blank to 0.65~0.75 T. 熔 Perform homogenization annealing, holding time 2 ~ 10 h; Step (6) Blank extrusion: The homogenized and annealed welding wire rod blank is extruded through multiple passes to obtain welding wire wire rod blank with a diameter of φ5~8 mm; Step (7) First annealing: The extruded welding wire rod blank is subjected to a first heating annealing at a temperature of 0.75 ~ 0.85 T. 熔 ; Step (8) Drawing into wire: The above-mentioned annealed welding wire rod blank is continuously drawn using a wire drawing machine to obtain a welding wire blank with a diameter of φ3 ~ 4 mm; Step (9) Secondary annealing: The welding wire blank is heated and annealed a second time at a temperature of 0.72 ~ 0.82T. 熔 ; Step (10) Finished product drawing: The annealed welding wire blank is drawn into finished products to obtain aluminum alloy foamed welding wire finished products with diameters of φ1.2, 1.6, 2.0, 3.2 and 4.0 mm; Step (11) Cleaning and drying: The finished aluminum alloy foamed welding wire is ultrasonically cleaned and then dried with hot air. Step (12) Wire Coiling and Packaging: The dried aluminum alloy foamed welding wire is continuously coiled and vacuum-packed.

[0007] As a preferred embodiment, the aluminum alloy matrix in step 1 is an Al-Cu aluminum alloy, an Al-Mg aluminum alloy, an Al-Si aluminum alloy, an Al-Mg-Si aluminum alloy, or an Al-Zn-Mg-Cu aluminum alloy, and the total mass fraction of alloying elements in the aluminum alloy foamed welding wire does not exceed 20%.

[0008] As a preferred embodiment, the foaming stabilizer in step 2 includes two types of substances: the first type is one or any combination of Ca and Mg metallic elements, with an addition amount of 0.1 to 4.0 wt.%; the second type is one or any combination of Al2O3, ZrO2, SiC, TiC, and B4C particulate additives with high melting points, with a particle size of 300 to 1000 mesh, and an addition amount of 0.5 to 3.0 wt.%.

[0009] As a preferred option, the stirring method is one or any combination of mechanical stirring, ultrasonic stirring, and electromagnetic stirring.

[0010] As a preferred embodiment, the amount of high-temperature foam added is 0.5 ~ 4 wt.%, and the high-temperature foam is composed of two types of substances: foaming agent and carrier particles. The foaming agent and carrier particles are mixed by ball milling process, with a ball-to-material ratio of 3:1 ~ 10:1, a ball milling speed of 200 ~ 1000 r / min, and a ball milling time of 2 ~ 12 h.

[0011] Furthermore, the foaming agent is a carbonate of CaCO3, MgCO3, or CaMg(CO3)2 that releases CO2 upon thermal decomposition, and a metal hydride of TiH2, MgH2, or CaH2 that releases H2 upon thermal decomposition, wherein the particle size of the foaming agent is 100-500 mesh; the carrier particles are one or any combination of plastically deformable Al, Cu, Mg, and their alloy particles, wherein the particle size of the carrier particles is 80-400 mesh.

[0012] As a preferred embodiment, the metal mold in step 4 is a cavity with an inner diameter between φ100 and 200 mm and an inner height between 300 and 500 mm. Cooling water channels with an inner diameter between φ8 and 15 mm are evenly distributed inside the cavity wall of the metal mold. The inlet temperature of the cooling water is 5℃ to 20℃ and the inlet pressure is between 0.3 and 0.8 MPa.

[0013] As a preferred embodiment, the extrusion ratio of each pass in the multi-pass extrusion in step 6 is 8% to 16%, and the extrusion temperature of the welding wire rod billet is 0.67 to 0.77 T. 熔 .

[0014] As a preferred option, step 8 involves using one or any combination of solid lubricants such as calcium stearate, barium stearate, zinc stearate, aluminum stearate, and sodium stearate to obtain the drawn wire.

[0015] As a preferred embodiment, the temperature of the ultrasonic cleaning liquid in step 11 is 45℃~60℃, the temperature of the hot air for drying is 70℃~80℃, and the drying air velocity is 0.5~3 m / s.

[0016] Compared with existing aluminum alloy welding wires, the present invention can achieve rapid filling and connection of the weld area after welding aluminum alloy materials, and the weld filling area exhibits a typical porous morphology. Compared with existing aluminum alloy welding wires, this invention can realize the direct welding of lightweight porous aluminum alloy materials, avoid the solidification of the weld area, and contribute to lightweight design. This invention can realize the welding foam filling of metal component cavities. Due to the foaming of the molten pool, the cavity filling efficiency can be greatly improved, and the metal component after forming can be endowed with functional characteristics such as damping and vibration reduction. This invention can be used as an additive manufacturing welding wire, and can be used to directly prepare porous aluminum alloy materials through additive manufacturing.

[0017] Additional aspects and advantages of the invention will become apparent in the following description or may be learned by practice of the invention. Attached Figure Description

[0018] The above and / or additional aspects and advantages of the present invention will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which: Figure 1 This is a flowchart of the preparation process of the present invention; Figure 2 This is a schematic diagram of the cross-section of aluminum alloy foamed welding wire; Figure 3 A schematic diagram of filling the weld seam with the aluminum alloy foamed welding wire of the present invention. Detailed Implementation

[0019] To better understand the above-mentioned objectives, features, and advantages of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be noted that, unless otherwise specified, the embodiments and features described in these embodiments can be combined with each other.

[0020] Many specific details are set forth in the following description in order to provide a full understanding of the invention. However, the invention may also be practiced in other ways different from those described herein, and therefore the scope of protection of the invention is not limited to the specific embodiments disclosed below.

[0021] The following is combined with Figures 1 to 3 The method for preparing aluminum alloy foamed welding wire according to embodiments of the present invention will be described in detail.

[0022] like Figure 1 As shown, this invention proposes a method for preparing aluminum alloy foamed welding wire, comprising the following steps: Example 1 A method for preparing aluminum alloy foamed welding wire includes the following steps: Step (1) Aluminum molten metal melting: Add the aluminum alloy matrix with the preset chemical composition to the melting furnace, heat and melt it. After all the furnace charge has melted, stir and clean the slag. The aluminum alloy matrix is ​​an Al-Cu series aluminum alloy, and the total mass fraction of alloy elements in the aluminum alloy foamed welding wire is 10%.

[0023] Step (2) Adding foaming stabilizer: Transfer the molten aluminum alloy to the tundish and adjust the temperature of the molten aluminum alloy to 1.1 T. 熔 Add a foaming stabilizer to the molten aluminum alloy and perform a first stirring and mixing process for 3 minutes; T 熔 The melting point temperature of the aluminum alloy matrix is ​​given. The foaming stabilizer consists of two types of substances: the first type is elemental Ca metal, with an addition amount of 0.1 wt.%; the second type is particulate Al2O3 with a particle size of 350 mesh, with an addition amount of 0.8 wt.%.

[0024] Step (3) Add high-temperature foaming material: Adjust the temperature of the aluminum alloy melt to T 熔 The high-temperature foam was added to the aluminum alloy melt and mixed a second time for 1 minute. The amount of high-temperature foam added was 0.5 wt.%, and the high-temperature foam consisted of two types of substances: a foaming agent and carrier particles. The foaming agent and carrier particles were mixed using a ball milling process with a ball-to-material ratio of 3:1, a ball milling speed of 500 r / min, and a ball milling time of 2 hours. The foaming agent refers to a single foaming agent or any combination of several foaming agents that can thermally decompose to produce gas under high-temperature conditions. The foaming agent was CaCO3 and TiH2, and the particle size of the foaming agent was 100 mesh. The carrier particles were any combination of plastically deformable Al and Cu, and the particle size of the carrier particles was 80 mesh.

[0025] Step (4) Rapid cooling: After the second stirring and mixing, the aluminum alloy melt in the tundish is poured into the metal mold, and cooling water is passed through to cool the mold to form a welding wire rod-shaped billet; the metal mold is a cavity with an inner diameter of φ100 mm and an inner height of 300 mm. Cooling water channels with an inner diameter of φ8 mm are evenly distributed in the cavity wall of the metal mold. The inlet temperature of the cooling water is 10℃ and the inlet pressure is between 0.3MPa.

[0026] Step (5) Homogenization annealing: Heat the welding wire rod blank to 0.65T 熔 Perform homogenization annealing and hold for 2 hours; Step (6) Billet Extrusion: The homogenized and annealed welding wire rod billet is extruded through multiple passes to obtain a welding wire wire rod billet with a diameter of φ5mm; the extrusion ratio of each pass in the multiple extrusion is 8%, and the extrusion temperature of the welding wire rod billet is 0.67T. 熔 .

[0027] Step (7) First annealing: The extruded welding wire rod blank is subjected to a first heating annealing at a temperature of 0.75T. 熔 ; Step (8) Wire drawing: The above-mentioned annealed wire rod blank is continuously drawn using a wire drawing machine to obtain a wire blank with a diameter of φ3 mm; calcium stearate solid lubricant is used for wire drawing.

[0028] Step (9) Secondary annealing: The welding wire blank is heated and annealed a second time at a temperature of 0.72T. 熔 ; Step (10) Finished product drawing: The annealed welding wire blank is drawn into a finished product to obtain aluminum alloy foamed welding wire with a diameter of φ1.2 mm; Step (11) Cleaning and drying: The aluminum alloy foamed welding wire is ultrasonically cleaned and then dried with hot air; the temperature of the ultrasonic cleaning liquid is 45℃, the temperature of the hot air for drying is 70℃, and the drying wind speed is 0.5 m / s.

[0029] Step (12) Wire Coiling and Packaging: The dried aluminum alloy foamed welding wire is continuously coiled and vacuum-packed.

[0030] Example 2 A method for preparing aluminum alloy foamed welding wire includes the following steps: Step (1) Aluminum liquid smelting: Add the aluminum alloy matrix with the preset chemical composition to the smelting furnace, heat and melt it. After all the furnace charge has melted, stir and clean the slag. The aluminum alloy matrix is ​​an Al-Mg series aluminum alloy, and the total mass fraction of alloy elements in the aluminum alloy foamed welding wire is 12%.

[0031] Step (2) Adding foaming stabilizer: Transfer the molten aluminum alloy to the tundish and adjust the temperature of the molten aluminum alloy to 1.1 T. 熔 Add a foaming stabilizer to the molten aluminum alloy and perform a first stirring and mixing process for 5 minutes; T 熔 The melting point temperature of the aluminum alloy matrix is ​​given. The foaming stabilizer consists of two types of substances: the first type is elemental Ca metal, with an addition amount of 0.5 wt.%; the second type is particulate ZrO2 with a particle size of 300 mesh, with an addition amount of 0.5 wt.%.

[0032] Step (3) Add high-temperature foaming material: Adjust the temperature of the aluminum alloy melt to T 熔The high-temperature foam was added to the aluminum alloy melt and mixed a second time for 2 minutes. The amount of high-temperature foam added was 1.0 wt.%. The high-temperature foam consisted of two types of substances: a foaming agent and carrier particles. The foaming agent and carrier particles were mixed using a ball milling process with a ball-to-material ratio of 5:1, a ball milling speed of 200 r / min, and a ball milling time of 5 hours. The foaming agent refers to a single foaming agent or any combination of several foaming agents that can thermally decompose to produce gas under high-temperature conditions. The foaming agent was a carbonate of MgCO3 that releases CO2 through thermal decomposition and a metal hydride of MgH2 that releases H2 through thermal decomposition. The particle size of the foaming agent was 200 mesh. The carrier particles were any combination of plastically deformable Al and Cu, with a particle size of 100 mesh.

[0033] Step (4) Rapid cooling: After the second mixing is completed, the aluminum alloy melt in the intermediate ladle is poured into the metal mold and cooling water is passed through to cool the mold to form a welding wire rod-shaped billet; the metal mold is a cavity with an inner diameter of φ100 mm and an inner height of 300 mm. Cooling water channels with an inner diameter of φ10 mm are evenly distributed in the cavity wall of the metal mold. The inlet temperature of the cooling water is 10℃ and the inlet pressure is between 0.5MPa.

[0034] Step (5) Homogenization annealing: Heat the welding wire rod blank to 0.65T 熔 Perform homogenization annealing and hold for 3 hours; Step (6) Billet Extrusion: The homogenized and annealed welding wire rod billet is extruded through multiple passes to obtain a welding wire wire rod billet with a diameter of φ6mm; the extrusion ratio of each pass in the multiple extrusion is 10%, and the extrusion temperature of the welding wire rod billet is 0.67T. 熔 .

[0035] Step (7) First annealing: The extruded welding wire rod blank is subjected to a first heating annealing at a temperature of 0.80 T. 熔 ; Step (8) Wire drawing: The above-mentioned annealed wire rod blank is continuously drawn using a wire drawing machine to obtain a wire blank with a diameter of φ3 mm; calcium stearate solid lubricant is used for wire drawing.

[0036] Step (9) Secondary annealing: The welding wire blank is heated and annealed a second time at a temperature of 0.75T. 熔 ; Step (10) Finished product drawing: The annealed welding wire blank is drawn into a finished product to obtain aluminum alloy foamed welding wire with a diameter of φ1.6 mm; Step (11) Cleaning and drying: The aluminum alloy foamed welding wire is ultrasonically cleaned and then dried with hot air; the temperature of the ultrasonic cleaning liquid is 50℃, the temperature of the hot air for drying is 70℃, and the drying wind speed is 0.5 m / s.

[0037] Step (12) Wire Coiling and Packaging: The dried aluminum alloy foamed welding wire is continuously coiled and vacuum-packed.

[0038] Example 3 A method for preparing aluminum alloy foamed welding wire includes the following steps: Step (1) Aluminum liquid smelting: Add the aluminum alloy matrix with the preset chemical composition to the smelting furnace, heat and melt it. After all the furnace charge has melted, stir and clean the slag. The aluminum alloy matrix is ​​an Al-Si aluminum alloy, and the total mass fraction of alloying elements in the aluminum alloy foamed welding wire is 10%.

[0039] Step (2) Adding foaming stabilizer: Transfer the molten aluminum alloy to the tundish and adjust the temperature of the molten aluminum alloy to 1.1 T. 熔 A foaming stabilizer was added to the molten aluminum alloy, and the mixture was stirred for the first time for 6 minutes; T 熔 The melting point temperature of the aluminum alloy matrix is ​​given. The foaming stabilizer consists of two types of substances: the first type is elemental Mg metal, with an addition amount of 1.0 wt.%; the second type is particulate Al2O3 with a particle size of 200 mesh, with an addition amount of 1.0 wt.%.

[0040] Step (3) Add high-temperature foaming material: Adjust the temperature of the aluminum alloy melt to 1.1T. 熔 The high-temperature foam was added to the aluminum alloy melt and mixed a second time for 0.5 min. The amount of high-temperature foam added was 0.5 wt.%, and the high-temperature foam consisted of two types of substances: a foaming agent and carrier particles. The foaming agent and carrier particles were mixed using a ball milling process with a ball-to-material ratio of 4:1, a ball milling speed of 500 r / min, and a ball milling time of 5 h. The foaming agent refers to a single foaming agent or any combination of several foaming agents that can thermally decompose to produce gas under high-temperature conditions. The foaming agent was a carbonate of CaMg(CO3)2 that releases CO2 through thermal decomposition and a metal hydride of TiH2 that releases H2 through thermal decomposition. The particle size of the foaming agent was 400 mesh. The carrier particles were any combination of plastically deformable Al and Mg, and the particle size of the carrier particles was 300 mesh.

[0041] Step (4) Rapid cooling: After the second mixing is completed, the aluminum alloy melt in the tundish is poured into the metal mold and cooling water is passed through to cool the mold to form a welding wire rod-shaped billet; the metal mold is a cavity with an inner diameter of φ200 mm and an inner height of 500 mm. Cooling water channels with an inner diameter of φ15 mm are evenly distributed in the cavity wall of the metal mold. The inlet temperature of the cooling water is 20℃ and the inlet pressure is between 0.8MPa.

[0042] Step (5) Homogenization annealing: Heat the welding wire rod blank to 0.75T熔 Perform homogenization annealing and hold for 5 hours; Step (6) Billet Extrusion: The homogenized and annealed welding wire rod billet is extruded through multiple passes to obtain a welding wire wire rod billet with a diameter of φ8mm; the extrusion ratio of each pass in the multiple extrusion is 10%, and the extrusion temperature of the welding wire rod billet is 0.77T. 熔 .

[0043] Step (7) First annealing: The extruded welding wire rod blank is subjected to a first heating annealing at a temperature of 0.85 T. 熔 ; Step (8) Wire drawing: The above-mentioned annealed wire rod blank is continuously drawn using a wire drawing machine to obtain a wire blank with a diameter of φ4 mm; calcium stearate solid lubricant is used for wire drawing.

[0044] Step (9) Secondary annealing: The welding wire blank is heated and annealed a second time at a temperature of 0.8 T. 熔 ; Step (10) Finished product drawing: The annealed welding wire blank is drawn into a finished product to obtain aluminum alloy foamed welding wire with a diameter of φ2.0 mm; Step (11) Cleaning and drying: The aluminum alloy foamed welding wire is ultrasonically cleaned and then dried with hot air; the temperature of the ultrasonic cleaning liquid is 60℃, the temperature of the hot air for drying is 75℃, and the drying wind speed is 3 m / s.

[0045] Step (12) Wire Coiling and Packaging: The dried aluminum alloy foamed welding wire is continuously coiled and vacuum-packed.

[0046] Example 4 A method for preparing aluminum alloy foamed welding wire includes the following steps: Step (1) Aluminum liquid smelting: Add the aluminum alloy matrix with the preset chemical composition into the smelting furnace, heat and melt it. After all the furnace charge has melted, stir and clean the slag. The aluminum alloy matrix is ​​an Al-Mg-Si aluminum alloy, and the total mass fraction of alloying elements in the aluminum alloy foamed welding wire is 15%.

[0047] Step (2) Adding foaming stabilizer: Transfer the molten aluminum alloy to the tundish and adjust the temperature of the molten aluminum alloy to 1.2 T. 熔 Add a foaming stabilizer to the molten aluminum alloy and perform a first stirring and mixing process for 10 minutes; T 熔 The melting point temperature of the aluminum alloy matrix is ​​given. The foaming stabilizer consists of two types of substances: the first type is elemental Mg metal, with an addition amount of 3.0 wt.%; the second type is TiC particulate additive with a particle size of 500 mesh, with an addition amount of 3.0 wt.%.

[0048] Step (3) Add high-temperature foaming material: Adjust the temperature of the aluminum alloy melt to 1.1T. 熔 High-temperature foaming material was added to the aluminum alloy melt and mixed a second time for 2.0 min. The amount of high-temperature foaming material added was 2.0 wt.%, and the high-temperature foaming material consisted of two types of substances: foaming agent and carrier particles. The foaming agent and carrier particles were mixed by ball milling at a ball-to-material ratio of 8:1, a ball milling speed of 1000 r / min, and a ball milling time of 10 h. The foaming agent refers to a single foaming agent or any combination of several foaming agents that can thermally decompose to produce gas under high-temperature conditions. The foaming agent was a carbonate of CaMg(CO3)2 that releases CO2 through thermal decomposition and a metal hydride of CaH2 that releases H2 through thermal decomposition. The particle size of the foaming agent was 100 mesh. The carrier particles were any combination of plastically deformable Al and Mg, and the particle size of the carrier particles was 400 mesh.

[0049] Step (4) Rapid cooling: After the second mixing is completed, the aluminum alloy melt in the intermediate ladle is poured into the metal mold and cooling water is passed through to cool the mold to form a welding wire rod-shaped billet; the metal mold is a cavity with an inner diameter of φ100 mm and an inner height of 300 mm. Cooling water channels with an inner diameter of φ10 mm are evenly distributed in the cavity wall of the metal mold. The inlet temperature of the cooling water is 10℃ and the inlet pressure is between 0.5MPa.

[0050] Step (5) Homogenization annealing: Heat the welding wire rod blank to 0.7T. 熔 Perform homogenization annealing and hold at the temperature for 10 hours; Step (6) Billet Extrusion: The homogenized and annealed welding wire rod billet is extruded through multiple passes to obtain a welding wire wire rod billet with a diameter of φ7mm; the extrusion ratio of each pass in the multiple extrusion is 16%, and the extrusion temperature of the welding wire rod billet is 0.67T. 熔 .

[0051] Step (7) First annealing: The extruded welding wire rod blank is subjected to a first heating annealing at a temperature of 0.80 T. 熔 ; Step (8) Wire drawing: The above-mentioned annealed wire rod blank is continuously drawn using a wire drawing machine to obtain a wire blank with a diameter of φ4 mm; calcium stearate solid lubricant is used for wire drawing.

[0052] Step (9) Secondary annealing: The welding wire blank is heated and annealed a second time at a temperature of 0.8 T. 熔 ; Step (10) Finished product drawing: The annealed welding wire blank is drawn into a finished product to obtain aluminum alloy foamed welding wire with a diameter of φ3.2 mm; Step (11) Cleaning and drying: The aluminum alloy foamed welding wire is ultrasonically cleaned and then dried with hot air; the temperature of the ultrasonic cleaning liquid is 55℃, the temperature of the hot air for drying is 80℃, and the drying wind speed is 1 m / s.

[0053] Step (12) Wire Coiling and Packaging: The dried aluminum alloy foamed welding wire is continuously coiled and vacuum-packed.

[0054] Example 5 A method for preparing aluminum alloy foamed welding wire includes the following steps: Step (1) Aluminum liquid smelting: Add the aluminum alloy matrix with the preset chemical composition into the smelting furnace, heat and melt it. After all the furnace charge has melted, stir and clean the slag. The aluminum alloy matrix is ​​an Al-Zn-Mg-Cu series aluminum alloy, and the total mass fraction of alloy elements in the aluminum alloy foamed welding wire is 10%.

[0055] Step (2) Adding foaming stabilizer: Transfer the molten aluminum alloy to the tundish and adjust the temperature of the molten aluminum alloy to 1.2 T. 熔 A foaming stabilizer was added to the molten aluminum alloy, and the mixture was stirred for the first time for 8 minutes; T 熔 The melting point temperature of the aluminum alloy matrix is ​​given. The foaming stabilizer consists of two types of substances: the first type is elemental Ca metal, with an addition amount of 4.0 wt.%; the second type is B4C particulate additive with a particle size of 1000 mesh, with an addition amount of 2.0 wt.%.

[0056] Step (3) Add high-temperature foaming material: Adjust the temperature of the aluminum alloy melt to T 熔 High-temperature foaming material was added to the aluminum alloy melt and mixed a second time for 4.0 min. The amount of high-temperature foaming material added was 4.0 wt.%, and the high-temperature foaming material consisted of two types of substances: foaming agent and carrier particles. The foaming agent and carrier particles were mixed by ball milling at a ball-to-material ratio of 10:1, a ball milling speed of 800 r / min, and a ball milling time of 8 h. The foaming agent refers to a single foaming agent or any combination of several foaming agents that can thermally decompose to produce gas under high-temperature conditions. The foaming agent was a carbonate of CaMg(CO3)2 that releases CO2 through thermal decomposition and a metal hydride of CaH2 that releases H2 through thermal decomposition. The particle size of the foaming agent was 500 mesh. The carrier particles were any combination of plastically deformable Al and Cu, and the particle size of the carrier particles was 400 mesh.

[0057] Step (4) Rapid cooling: After the second stirring and mixing, the aluminum alloy melt in the intermediate ladle is poured into the metal mold, and cooling water is passed through to cool the mold to form a welding wire rod-shaped billet; the metal mold is a cavity with an inner diameter of φ100 mm and an inner height of 500 mm. Cooling water channels with an inner diameter of φ10 mm are evenly distributed in the cavity wall of the metal mold. The inlet temperature of the cooling water is 10℃ and the inlet pressure is between 0.5 MPa.

[0058] Step (5) Homogenization annealing: Heat the welding wire rod blank to 0.7T. 熔 Perform homogenization annealing and hold for 10 hours; Step (6) Billet Extrusion: The homogenized and annealed welding wire rod billet is extruded through multiple passes to obtain a welding wire wire rod billet with a diameter of φ7mm; the extrusion ratio of each pass in the multiple extrusion is 16%, and the extrusion temperature of the welding wire rod billet is 0.77T. 熔 .

[0059] Step (7) First annealing: The extruded welding wire rod blank is subjected to a first heating annealing at a temperature of 0.80 T. 熔 ; Step (8) Wire drawing: The above-mentioned annealed wire rod blank is continuously drawn using a wire drawing machine to obtain a wire blank with a diameter of φ4 mm; calcium stearate solid lubricant is used for wire drawing.

[0060] Step (9) Secondary annealing: The welding wire blank is heated and annealed a second time at a temperature of 0.8 T. 熔 ; Step (10) Finished product drawing: The annealed welding wire blank is drawn into a finished product to obtain aluminum alloy foamed welding wire with a diameter of φ4.0 mm; Step (11) Cleaning and drying: The aluminum alloy foamed welding wire is ultrasonically cleaned and then dried with hot air; the temperature of the ultrasonic cleaning liquid is 50℃, the temperature of the hot air for drying is 80℃, and the drying wind speed is 1 m / s.

[0061] Step (12) Wire Coiling and Packaging: The dried aluminum alloy foamed welding wire is continuously coiled and vacuum-packed.

[0062] Results and Discussion Table 1. Aluminum alloy foamed welding wires prepared using different embodiments. Table 2. Experimental results of aluminum alloy flux using different aluminum alloy foamed welding wires prepared according to the examples. Table 2 shows different welding wires prepared with different diameters, including 1.2 mm, 1.6 mm, 2.0 mm, 3.2 mm, and 4.0 mm. Compared with existing aluminum alloy welding wires, this invention enables rapid filling and connection of aluminum alloy weld areas, and the weld filling area exhibits a typical porous morphology. The average size of the pores in the weld area (0.8 ~ 2.5 mm) and the porosity (43% ~ 73%) are affected by the high-temperature foam in the aluminum alloy foamed welding wire and the welding process parameters. The porous weld area allows the aluminum alloy foamed welding wire to be directly applied to the welding and forming of porous aluminum alloy materials, avoiding the solid weld that occurs after forming with traditional aluminum alloy welding wires. Using the examples, “surfacing” on the aluminum alloy surface yields a lightweight foamed layer with a porous morphology that is well bonded to the aluminum alloy matrix, with a load-bearing strength of 6.5 ~ 20.5 MPa. The porous surface structure can endow metal components with damping and vibration reduction functional properties. The aluminum alloy foamed welding wire of the embodiment can be used as an additive manufacturing welding wire to realize the additive preparation and forming of porous aluminum alloy materials and improve production efficiency.

[0063] In the description of this invention, the term "a plurality of" refers to two or more. Unless otherwise explicitly defined, the terms "upper," "lower," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. The terms "connection," "installation," "fixing," etc., should be interpreted broadly. For example, "connection" can be a fixed connection, a detachable connection, or an integral connection; it can be a direct connection or an indirect connection through an intermediate medium. For those skilled in the art, the specific meaning of the above terms in this invention can be understood according to the specific circumstances.

[0064] In the description of this specification, the terms "one embodiment," "some embodiments," "specific embodiment," etc., refer to a specific feature, structure, material, or characteristic described in connection with that embodiment or example, which is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0065] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for preparing aluminum alloy foamed welding wire, characterized in that... This includes the following steps: Step (1) Aluminum molten metal smelting: Add the aluminum alloy matrix with the preset chemical composition into the smelting furnace, heat and melt it. After all the furnace charge has melted, stir and remove the slag. Step (2) Adding foaming stabilizer: Transfer the molten aluminum alloy to the tundish and adjust the temperature of the molten aluminum alloy to 1.1 ~ 1.2 T. 熔 Add a foaming stabilizer to the molten aluminum alloy and perform a first stirring and mixing process for 3 to 10 minutes; T 熔 This refers to the melting point temperature of the aluminum alloy matrix. Step (3) Add high-temperature foaming material: Adjust the temperature of the aluminum alloy melt to T 熔 ~ 1.1 T 熔 The high-temperature foam is added to the aluminum alloy melt and then stirred and mixed for a second time for 0.5 to 4 minutes. Step (4) Rapid cooling: After the second stirring and mixing is completed, the aluminum alloy melt in the tundish is poured into the metal mold, and cooling water is passed through to cool the mold to form a welding wire rod billet; Step (5) Homogenization annealing: Heat the welding wire rod blank to 0.65~0.75 T. 熔 Perform homogenization annealing, holding time 2 ~ 10 h; Step (6) Blank extrusion: The homogenized and annealed welding wire rod blank is extruded through multiple passes to obtain welding wire wire rod blank with a diameter of φ5~8mm; Step (7) First annealing: The extruded welding wire rod blank is subjected to a first heating annealing at a temperature of 0.75 ~ 0.85 T. 熔 ; Step (8) Drawing into wire: The above-mentioned annealed welding wire rod blank is continuously drawn using a wire drawing machine to obtain a welding wire blank with a diameter of φ3 ~ 4 mm; Step (9) Secondary annealing: The welding wire blank is heated and annealed a second time at a temperature of 0.72 ~ 0.82 T. 熔 ; Step (10) Finished product drawing: The annealed welding wire blank is drawn into finished products to obtain aluminum alloy foamed welding wire finished products with diameters of φ1.2, 1.6, 2.0, 3.2 and 4.0 mm; Step (11) Cleaning and drying: The finished aluminum alloy foamed welding wire is ultrasonically cleaned and then dried with hot air. Step (12) Wire Coiling and Packaging: The dried aluminum alloy foamed welding wire is continuously coiled and vacuum-packed.

2. The method for preparing aluminum alloy foamed welding wire according to claim 1, characterized in that... The aluminum alloy matrix in step (1) is one or any combination of Al-Cu aluminum alloy, Al-Mg aluminum alloy, Al-Si aluminum alloy, Al-Mg-Si aluminum alloy, and Al-Zn-Mg-Cu aluminum alloy, and the total mass fraction of alloying elements in the aluminum alloy foamed welding wire does not exceed 20%.

3. The method for preparing aluminum alloy foamed welding wire according to claim 1, characterized in that... The foaming stabilizer in step (2) includes two types of substances: the first type is one or any combination of Ca and Mg metal elements, with an addition amount of 0.1 to 4.0 wt.%; the second type is one or any combination of Al2O3, ZrO2, SiC, TiC, and B4C particles with high melting points, with a particle size of 300 to 1000 mesh, and an addition amount of 0.5 to 3.0 wt.%.

4. The method for preparing aluminum alloy foamed welding wire according to claim 1, characterized in that... The stirring method is one or any combination of mechanical stirring, ultrasonic stirring, and electromagnetic stirring.

5. The method for preparing aluminum alloy foamed welding wire according to claim 1, characterized in that... The high-temperature foam is added at a rate of 0.5 to 4 wt.%, and the high-temperature foam is composed of two types of substances: foaming agent and carrier particles. The foaming agent and carrier particles are mixed by ball milling, with a ball-to-material ratio of 3:1 to 10:1, a ball milling speed of 200 to 1000 r / min, and a ball milling time of 2 to 12 h.

6. The method for preparing aluminum alloy foamed welding wire according to claim 5, characterized in that, The foaming agent is a carbonate of CaCO3, MgCO3, or CaMg(CO3)2 that releases CO2 upon thermal decomposition, and a metal hydride of TiH2, MgH2, or CaH2 that releases H2 upon thermal decomposition. The particle size of the foaming agent is 100-500 mesh. The carrier particles are one or any combination of plastically deformable Al, Cu, Mg, and their alloy particles. The particle size of the carrier particles is 80-400 mesh.

7. The method for preparing aluminum alloy foamed welding wire according to claim 1, characterized in that... The metal mold in step (4) is a cavity with an inner diameter between φ100 and 200 mm and an inner height between 300 and 500 mm. Cooling water channels with an inner diameter of φ8 to 15 mm are evenly distributed inside the cavity wall of the metal mold. The inlet temperature of the cooling water is 5℃ to 20℃ and the inlet pressure is between 0.3 and 0.8 MPa.

8. The method for preparing aluminum alloy foamed welding wire according to claim 1, characterized in that... In step (6), the extrusion ratio of each pass in the multi-pass extrusion is 8% to 16%, and the extrusion temperature of the welding wire rod billet is 0.67 to 0.77 T. 熔 .

9. The method for preparing aluminum alloy foamed welding wire according to claim 1, characterized in that... In step (8), the solid lubricant used to draw the wire is one or any combination of calcium stearate, barium stearate, zinc stearate, aluminum stearate, and sodium stearate.

10. The method for preparing aluminum alloy foamed welding wire according to claim 1, characterized in that... The temperature of the ultrasonic cleaning liquid in step 11 is 45℃ ~ 60℃, the temperature of the hot air for drying is 70℃ ~ 80℃, and the drying air velocity is 0.5 ~ 3 m / s.

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