An aluminum-clad titanium composite welding wire and its preparation method

Abstract

This invention discloses an aluminum-clad titanium composite welding wire, comprising a titanium rod and an aluminum sleeve covering the titanium rod. The cross-sectional area ratio of the aluminum sleeve to the titanium rod is 1:1 to 1.5. Furthermore, this invention provides a method for preparing the aluminum-clad titanium composite welding wire, in which a titanium raw material rod is placed inside an aluminum alloy sleeve, and aluminum-clad titanium composite welding wires of different diameters and composite ratios are prepared through hot extrusion, cold drawing, and annealing processes. The aluminum-clad titanium composite welding wire of this invention uses aluminum alloy as the outer cladding material. Aluminum alloy has low deformation resistance, which can reduce the tonnage requirement of equipment and save costs. Aluminum alloy has good oxidation resistance; the oxide film formed by the aluminum alloy at room temperature and high temperature air is dense, effectively preventing further surface oxidation. The resulting aluminum-clad titanium composite welding wire has good internal structure uniformity and performance consistency, ensuring good conductivity during welding, further promoting arc stability, and improving product yield.

Description

Technical Field

[0001] This invention belongs to the technical field of aluminum-clad titanium composite welding wire, specifically relating to an aluminum-clad titanium composite welding wire and its preparation method. Background Technology

[0002] TiAl intermetallic compounds exhibit both metallic and covalent bonds, giving them properties similar to both metals and ceramics. These include high melting point, low density, high elastic modulus, good high-temperature strength (700℃~900℃), flame retardancy, and oxidation resistance, making them a promising new type of lightweight, high-temperature resistant structural material with significant application prospects in aerospace and automotive fields. However, despite these advantages, many problems remain to be solved. For example, low room-temperature plasticity and difficulty in hot working are two of the most significant drawbacks of TiAl alloys, hindering their large-scale industrial application.

[0003] Arc additive manufacturing technology is a method for manufacturing three-dimensional solid components based on the layer-by-layer welding of materials. Compared with traditional subtractive manufacturing technologies such as casting and forging, this technology has advantages such as simple process flow, high material utilization, high forming efficiency, and the ability to manufacture various complex structures, making it particularly suitable for manufacturing complex TiAl alloy components. Three invention patents, with publication numbers CN110605462A, CN112139650A, and CN112139649A, all involve methods for preparing TiAl alloys by fused wire deposition. These three patents employ a dual-wire feeding method, using a dual-wire feeding mechanism that controls titanium and aluminum wires to prepare TiAl alloys. However, the dual-wire feeding mechanism increases both equipment cost and the complexity of the equipment's motion mechanism. During the deposition process, issues such as motion interference inevitably affect the metal deposition path, which is unfavorable for manufacturing complex metal components and has certain limitations. To address the high complexity of wire feeding systems, patent CN113523643A proposes a method for preparing Ti / Al composite wires for additive manufacturing of TiAl alloys. This method uses a titanium-clad aluminum approach, employing processes such as rotary forging and drawing to prepare Ti / Al composite wires for additive manufacturing. This solves the problem that TiAl alloys have poor room temperature plasticity, making them difficult to draw and form, thus hindering their application in additive manufacturing. The purpose of aluminum-clad titanium is still for additive manufacturing. By designing the wire ratio, it is melted using methods such as electric arc, laser, plasma, or electron beam, and uniformly mixed in the molten pool to form TiAl metal. Using the principles of additive manufacturing, TiAl metal parts can be directly manufactured (TiAl metal is difficult to plastically process and machine). Combining Ti and Al within a single wire facilitates better fusion. If two wires are fed together, two sets of wire feeding equipment are required, and the welding wires will not mix evenly in the molten pool. This patent also has the following problems: Since titanium alloy is used as the outer cladding layer, its deformation resistance is greater than that of aluminum alloy. This requires deformation processing, such as extrusion and drawing, to use equipment with larger tonnage, which increases equipment and energy costs. In order to further reduce the deformation resistance of titanium alloy, hot drawing is usually carried out under heated conditions. However, titanium alloy has a strong tendency to absorb hydrogen and oxidize at high temperatures, which can easily produce oxide scale on the surface of the product. The oxide components can easily cause serious quality problems in later use. To solve this problem, the patent proposes to carry out heat treatment in a vacuum furnace, which further increases the process cost. In addition, the rotary forging + drawing method is relatively primitive. Multiple annealing processes are required from billet to wire, making the process quite complicated.

[0004] To solve the above technical problems, it is necessary to provide an aluminum-clad titanium composite welding wire and its preparation method. Summary of the Invention

[0005] The technical problem to be solved by this invention is to provide an aluminum-clad titanium composite welding wire that addresses the shortcomings of the prior art. This aluminum-clad titanium composite welding wire uses aluminum alloy as the outer cladding material. Aluminum alloy has low deformation resistance, which can reduce the tonnage requirement of the equipment and save costs. Aluminum alloy also has good oxidation resistance; it forms a dense oxide film at room temperature and in high-temperature air, effectively preventing further surface oxidation.

[0006] To solve the above-mentioned technical problems, the present invention provides a technical solution as follows: an aluminum-clad titanium composite welding wire, characterized in that the composite welding wire comprises a titanium material rod and an aluminum material sleeve covering the titanium material rod, wherein the cross-sectional area ratio of the aluminum material sleeve to the titanium material rod is 1:1 to 1.5. The present invention selects aluminum alloy as the outer cladding material. Aluminum alloy has low deformation resistance, which can reduce the tonnage requirement of the equipment and save costs. Aluminum alloy has good oxidation resistance; the oxide film formed by aluminum alloy at room temperature and high temperature air is dense, effectively preventing further surface oxidation. By controlling the cross-sectional area ratio of the aluminum material sleeve to the titanium material rod, it is suitable for different application conditions.

[0007] The above-mentioned aluminum-clad titanium composite welding wire is characterized in that the titanium material rod is made of titanium, titanium-vanadium alloy, titanium-nickel alloy, titanium-molybdenum alloy, or titanium-niobium alloy; the aluminum material sleeve is made of aluminum, aluminum-copper alloy, aluminum-magnesium alloy, aluminum-magnesium-silicon alloy, or aluminum-zinc-magnesium-copper alloy. The final weld composition after arc welding can be achieved by changing the composition of the aluminum alloy or titanium alloy.

[0008] In addition, the present invention provides a method for preparing aluminum-clad titanium composite welding wire, characterized in that the method includes the following steps:

[0009] Step 1: The titanium raw material is sequentially machined and turned and polished to obtain a titanium raw material rod; the diameter of the titanium raw material rod is 3mm to 30mm and the length is 100mm to 200mm.

[0010] Step 2: The aluminum raw material is sequentially machined and turned and polished to obtain an aluminum raw material sleeve; the inner diameter of the aluminum raw material sleeve is 3mm to 30mm, the outer diameter is 50mm to 80mm, and the length is 100mm to 200mm.

[0011] Step 3: After loading the titanium raw material rod obtained in Step 1 into the aluminum raw material sleeve obtained in Step 2, seal and weld both ends to obtain the assembly blank.

[0012] Step 4: After heating the assembly blank obtained in Step 3, perform hot extrusion, and then saw cut to remove the uneven sections at both ends to obtain the aluminum-clad titanium composite wire blank.

[0013] Step 5: The aluminum-clad titanium composite wire blank obtained in Step 4 is subjected to successive drawing and annealing processes to obtain aluminum-clad titanium composite welding wire.

[0014] This invention employs a hot extrusion method, which allows titanium and aluminum to undergo a single hot processing step, causing atoms at their interface to diffuse, dissolve, or form metallic compounds, thereby improving bonding strength. On the other hand, extrusion can rapidly reduce the diameter and accelerate filament formation.

[0015] The above method is characterized in that the grinding in step one is to grind the outer surface of the titanium raw material rod with 2000# sandpaper.

[0016] The above method is characterized in that the grinding in step two involves grinding the inner surface of the aluminum raw material sleeve with 2000# sandpaper.

[0017] This invention uses 2000# sandpaper to polish the outer surface of the titanium raw material rod and the inner surface of the aluminum raw material sleeve to achieve a suitable roughness, resulting in a tight bond and easy integration into a single material.

[0018] The above method is characterized in that the hot extrusion temperature in step four is 400℃~550℃, and the extrusion ratio is 8~20:1. This invention controls the hot extrusion temperature to partially soften aluminum and titanium, facilitating extrusion. At this temperature, the extrusion resistance of aluminum is low, which helps in extrusion molding, reduces equipment load, forms a good interfacial bond, and achieves the purpose of reducing diameter.

[0019] The above method is characterized in that, in step five, stress-relief annealing is performed when the deformation is 40% to 60% during the drawing process. The stress-relief annealing temperature is 500℃ to 550℃, and the time is 60 min to 120 min. This invention utilizes stress-relief annealing when the deformation is 40% to 60% because this deformation range represents a limited deformation amount for the aluminum-clad titanium composite wire blank. If the processing deformation exceeds this range, the accumulated plastic deformation becomes too large, exceeding the maximum deformation, which can easily lead to problems such as difficulty in drawing and surface tearing. Therefore, annealing is necessary to soften the material before further processing.

[0020] Compared with the prior art, the present invention has the following advantages:

[0021] 1. The aluminum-clad titanium composite welding wire of the present invention uses aluminum alloy as the outer cladding material. Aluminum alloy has low deformation resistance, which can reduce the tonnage requirement of the equipment and save costs. Aluminum alloy has good oxidation resistance. The aluminum alloy forms a dense oxide film at room temperature and high temperature air, which effectively prevents further aggravation of surface oxidation.

[0022] 2. This invention places titanium raw material rods inside an aluminum alloy sleeve and prepares aluminum-clad titanium wires of different diameters and composite ratios through extrusion, rotary forging, and drawing processes. Heat treatment such as annealing is performed under non-vacuum conditions, further simplifying the processing steps and reducing manufacturing costs. After the product is processed, the oxide film can be removed by a single cleaning, which is easier than removing oxides from the surface of titanium alloys. Aluminum alloys have good fluidity. The extrusion process is used instead of rotary forging. The blank is extruded under the triaxial force of the extrusion cylinder, which quickly achieves large plastic deformation of the raw material and saves the manufacturing cycle.

[0023] 3. The aluminum-clad titanium composite welding wire of the present invention has a significant impact on the surface conductivity of the wire during both welding and arc additive manufacturing processes. The conductivity of aluminum alloy is much higher than that of titanium alloy. The use of aluminum-clad titanium model can effectively ensure good conductivity during the welding process, further promote the stability of the arc, and improve the product yield.

[0024] 4. Compared with the previously reported application methods using dual or multiple wires, the aluminum-clad titanium composite welding wire of the present invention reduces the complexity of equipment and saves costs. After being combined into a single wire, it is fed into the welding pool, which enables faster mutual dissolution and reduces the occurrence of uneven weld composition. The aluminum alloy, as the outer metal, improves conductivity, stabilizes the arc, and also improves weld quality.

[0025] The technical solution of the present invention will be further described in detail below through embodiments. Detailed Implementation

[0026] Example 1

[0027] This embodiment includes the following steps:

[0028] Step 1: The TA1 titanium raw material is sequentially machined and turned and polished to obtain a titanium raw material rod; the titanium raw material rod has a diameter of 10mm and a length of 150mm; it is turned and polished to obtain a certain surface roughness;

[0029] Step 2: The L01 aluminum raw material is sequentially machined and turned and polished to obtain an aluminum raw material sleeve; the inner diameter of the aluminum raw material sleeve is 10mm, the outer diameter is 60mm, and the length is 150mm; it is turned and polished with 2000# sandpaper to obtain a certain surface roughness;

[0030] Step 3: After loading the titanium raw material rod obtained in Step 1 into the aluminum raw material sleeve obtained in Step 2, seal and weld both ends to obtain the assembly blank.

[0031] Step 4: The assembled blank obtained in Step 3 is heated and then hot-extruded, and then sawn to obtain aluminum-clad titanium composite wire blank; the hot extrusion temperature is 400℃.

[0032] Step 5: The aluminum-clad titanium composite wire blank obtained in Step 4 is subjected to successive drawing and annealing treatments to obtain aluminum-clad titanium composite welding wire; when the drawing deformation is 20%, stress-relief annealing is performed in a vacuum furnace at a temperature of 500°C for 60 minutes.

[0033] Example 2

[0034] This embodiment includes the following steps:

[0035] Step 1: The titanium-vanadium alloy raw material is sequentially machined and turned and polished to obtain a titanium raw material rod; the titanium raw material rod has a diameter of 3mm and a length of 100mm; it is turned and polished to obtain a certain surface roughness;

[0036] Step 2: The aluminum-copper alloy raw material is sequentially machined and turned and polished to obtain an aluminum raw material sleeve; the inner diameter of the aluminum raw material sleeve is 3mm, the outer diameter is 50mm, and the length is 100mm; it is turned and polished with 2000# sandpaper to obtain a certain surface roughness;

[0037] Step 3: After loading the titanium raw material rod obtained in Step 1 into the aluminum raw material sleeve obtained in Step 2, seal and weld both ends to obtain the assembly blank.

[0038] Step 4: The assembly blank obtained in Step 3 is heated and then hot-extruded, and then sawn to obtain aluminum-clad titanium composite wire blank; the hot extrusion temperature is 500℃.

[0039] Step 5: The aluminum-clad titanium composite wire blank obtained in Step 4 is subjected to successive drawing and annealing treatments to obtain aluminum-clad titanium composite welding wire; when the drawing deformation is 25%, stress-relief annealing is performed in a vacuum furnace at a temperature of 530°C for 100 minutes.

[0040] Example 3

[0041] This embodiment includes the following steps:

[0042] Step 1: The titanium-nickel alloy raw material is sequentially machined and turned and polished to obtain a titanium raw material rod; the titanium raw material rod has a diameter of 30mm and a length of 200mm; it is turned and polished to obtain a certain surface roughness;

[0043] Step 2: The aluminum-magnesium alloy raw material is sequentially machined and turned and polished to obtain an aluminum raw material sleeve; the inner diameter of the aluminum raw material sleeve is 30mm, the outer diameter is 80mm, and the length is 200mm; it is turned and polished with 2000# sandpaper to obtain a certain surface roughness;

[0044] Step 3: After loading the titanium raw material rod obtained in Step 1 into the aluminum raw material sleeve obtained in Step 2, seal and weld both ends to obtain the assembly blank.

[0045] Step 4: The assembly blank obtained in Step 3 is heated and then hot-extruded, and then sawn to obtain aluminum-clad titanium composite wire blank; the hot extrusion temperature is 550℃.

[0046] Step 5: The aluminum-clad titanium composite wire blank obtained in Step 4 is subjected to successive drawing and annealing processes to obtain aluminum-clad titanium composite welding wire; when the drawing deformation is 30%, stress-relief annealing is performed in a vacuum furnace at a temperature of 550°C for 120 minutes.

[0047] Example 4

[0048] This embodiment includes the following steps:

[0049] Step 1: The titanium-molybdenum alloy raw material is sequentially machined and turned and polished to obtain a titanium raw material rod; the titanium raw material rod has a diameter of 20mm and a length of 130mm; it is turned and polished to obtain a certain surface roughness;

[0050] Step 2: The aluminum-magnesium-silicon alloy raw material is sequentially machined and turned and polished to obtain an aluminum raw material sleeve; the inner diameter of the aluminum raw material sleeve is 20mm, the outer diameter is 60mm, and the length is 130mm; it is turned and polished with 2000# sandpaper to obtain a certain surface roughness.

[0051] Step 3: After loading the titanium raw material rod obtained in Step 1 into the aluminum raw material sleeve obtained in Step 2, seal and weld both ends to obtain the assembly blank.

[0052] Step 4: The assembled blank obtained in Step 3 is heated and then hot-extruded, and then sawn to obtain aluminum-clad titanium composite wire blank; the hot extrusion temperature is 520℃.

[0053] Step 5: The aluminum-clad titanium composite wire blank obtained in Step 4 is subjected to successive drawing and annealing treatments to obtain aluminum-clad titanium composite welding wire; when the drawing deformation is 5%, stress-relief annealing is performed in a vacuum furnace at a temperature of 525°C for 80 minutes.

[0054] Example 5

[0055] This embodiment includes the following steps:

[0056] Step 1: The titanium-niobium alloy raw material is sequentially machined and turned and polished to obtain a titanium raw material rod; the titanium raw material rod has a diameter of 5mm and a length of 180mm; it is turned and polished to obtain a certain surface roughness;

[0057] Step 2: The aluminum-zinc-magnesium-copper alloy raw materials are sequentially machined and turned and polished to obtain an aluminum raw material sleeve; the inner diameter of the aluminum raw material sleeve is 5mm, the outer diameter is 70mm, and the length is 180mm; it is turned and polished with 2000# sandpaper to obtain a certain surface roughness.

[0058] Step 3: After loading the titanium raw material rod obtained in Step 1 into the aluminum raw material sleeve obtained in Step 2, seal and weld both ends to obtain the assembly blank.

[0059] Step 4: The assembly blank obtained in Step 3 is heated and then hot-extruded, and then sawn to obtain aluminum-clad titanium composite wire blank; the hot extrusion temperature is 420℃.

[0060] Step 5: The aluminum-clad titanium composite wire blank obtained in Step 4 is subjected to successive drawing and annealing treatments to obtain aluminum-clad titanium composite welding wire; when the drawing deformation is 25%, stress-relief annealing is performed in a vacuum furnace at a temperature of 510°C for 70 minutes.

[0061] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention in any way. Any simple modifications, alterations, and equivalent changes made to the above embodiments based on the inventive essence shall still fall within the protection scope of the present invention.

Claims

1. A method for preparing aluminum-clad titanium composite welding wire, characterized in that, The composite welding wire includes a titanium rod and an aluminum sleeve covering the titanium rod, wherein the cross-sectional area ratio of the aluminum sleeve to the titanium rod is 1:1 to 1.

5. The method for preparing the aluminum-clad titanium composite welding wire includes the following steps: Step 1: The titanium raw material is sequentially machined and turned and polished to obtain a titanium raw material rod; the diameter of the titanium raw material rod is 3mm~30mm and the length is 100mm~200mm. Step 2: The aluminum raw material is sequentially machined and turned and polished to obtain an aluminum raw material sleeve; the inner diameter of the aluminum raw material sleeve is 3mm~30mm, the outer diameter is 50mm~80mm, and the length is 100mm~200mm. Step 3: After loading the titanium raw material rod obtained in Step 1 into the aluminum raw material sleeve obtained in Step 2, seal and weld both ends to obtain the assembly blank. Step 4: Heat the assembly blank obtained in Step 3 and then perform hot extrusion, followed by sawing to obtain aluminum-clad titanium composite wire blank; Step 5: The aluminum-clad titanium composite wire blank obtained in Step 4 is subjected to successive drawing and annealing processes to obtain aluminum-clad titanium composite welding wire.

2. The method for preparing aluminum-clad titanium composite welding wire according to claim 1, characterized in that, The titanium material rod is made of titanium, titanium-vanadium alloy, titanium-nickel alloy, titanium-molybdenum alloy, or titanium-niobium alloy; the aluminum material sleeve is made of aluminum, aluminum-copper alloy, aluminum-magnesium alloy, aluminum-magnesium-silicon alloy, or aluminum-zinc-magnesium-copper alloy.

3. The method for preparing aluminum-clad titanium composite welding wire according to claim 1, characterized in that, The polishing described in step one involves polishing the outer surface of the titanium raw material rod with 2000# sandpaper.

4. The method for preparing aluminum-clad titanium composite welding wire according to claim 1, characterized in that, The grinding process described in step two involves using 2000# sandpaper to grind the inner surface of the aluminum raw material sleeve.

5. The method for preparing aluminum-clad titanium composite welding wire according to claim 1, characterized in that, The hot extrusion temperature in step four is 400℃~550℃, and the extrusion ratio is 8~20:

1.

6. The method for preparing aluminum-clad titanium composite welding wire according to claim 1, characterized in that, In step five, when the deformation is 40% to 60% during the drawing process, stress-relief annealing is performed at a temperature of 500℃ to 550℃ for a time of 60 to 120 minutes.