A method for welding titanium and its alloys to steel or stainless steel.

Abstract

A welding method for titanium and its alloys to steel or stainless steel is disclosed. The titanium and its alloys are metallurgically bonded to steel or stainless steel through a mixed-element alloy, and this metallurgical bonding is achieved through argon arc welding. The chemical composition of the mixed-element alloy is as follows: copper 20%–80%, nickel 1%–70%, iron 1%–20%, carbon 0.001%–0.2%, cobalt 0.02%–0.3%, manganese 0.5%–2.0%, and zinc 0.1%–30%. The process of this invention is manual argon arc welding with filler wire. The welding process is simple and easy to implement. The mixed-element alloy welding wire used for the transition layer contains no Be or Ti components. The welding process requires no special control and does not form brittle intermetallic compounds. This method can weld composite materials of titanium alloys with different shapes and complex curved surfaces to steel or stainless steel.

Description

Technical Field

[0001] This invention belongs to the field of explosive processing technology for metal composite materials, specifically relating to a welding method for titanium and its alloys with steel or stainless steel. Background Technology

[0002] Titanium alloys, with their excellent mechanical properties and good corrosion resistance, are favored by designers and engineers in many fields. However, the high price of titanium alloys and their poor weldability with other metals limit their application range. With the development of metallurgical technology, the production capacity of titanium alloys has increased significantly, and the price of titanium alloys has dropped considerably, providing an economic basis for their widespread application. For a long time, the processing of composite materials of titanium alloys with other metals, especially carbon steel / stainless steel, has been hampered by the fact that titanium and iron easily form brittle intermetallic compounds, making it impossible to combine the two metals using traditional fusion welding methods. Explosive bonding is an ideal process technology for metallurgically bonding titanium and its alloys with steel or stainless steel. However, explosive bonding technology is suitable for processing simple planar composite materials. For complex curved surfaces or point and line composites of two metals, explosive bonding is either ineffective or prohibitively expensive. Currently, composite plates made of rolled titanium alloys and steel or stainless steel have also been developed. However, this process directly rolls titanium and steel or stainless steel together, completing the bonding of the two metals under high temperature, high pressure, and long-term conditions. This inevitably leads to the diffusion and combination of titanium and iron atoms, forming a brittle intermetallic compound layer, resulting in poor bonding strength and reliability. This is specifically manifested in the following three aspects:

[0003] 1. Existing technologies mainly focus on the traditional explosive bonding and the newly developed rolling bonding technologies to achieve the metallurgical bonding of titanium alloys with steel or stainless steel. These technologies can only achieve large-area bonding in simple planar or curved surfaces. They cannot be used for complex bonding surfaces, especially in small areas.

[0004] 2. Existing technologies have also emerged that use brazing to bond titanium alloys with steel or stainless steel. However, due to the low melting point of the brazing filler material (Ti25.5Zr24.4Cu39.7Ni10.4) and the limitations of the process, this technology is not easy to use widely.

[0005] 3. Existing technologies also include a process method that directly uses a high-entropy alloy welding wire (composed of the following components by atomic percentage: Ti 8-12%, Fe 15-18%, Be 30-33%, Ni 20-24%, Cu 20-24%) to perform TIG welding.

[0006] To address the bonding challenges between titanium alloys and other metals, a technique involving a transition layer and brazing has been proposed. The core of this technique is using brazing filler metal to isolate the titanium alloy from other metals (such as carbon steel or stainless steel), thus preventing the formation of brittle intermetallic compounds. However, brazing typically involves a low-melting-point mixture that melts under certain stable conditions, wetting the surfaces of the titanium alloy and other metals (such as carbon steel or stainless steel). After cooling or pressurized solidification, a bond is formed between the titanium alloy and the other metal. Clearly, the implementation of this bonding process is significantly limited by certain environmental and environmental conditions. Summary of the Invention

[0007] To address the aforementioned problems, this invention provides a welding method for titanium and its alloys with steel or stainless steel. The method effectively solves the welding connection problem between dissimilar metals such as titanium and its alloys and steel or stainless steel. It employs argon arc welding, welding a mixed metallic element alloy material as a transition layer between the titanium alloy and carbon steel or stainless steel, thereby forming a composite material with three metallurgically bonded layers. This achieves the fusion welding bond between the titanium alloy and carbon steel or stainless steel. The technical solution adopted is as follows:

[0008] A welding method for titanium and its alloys to steel or stainless steel, wherein titanium and its alloys are alloyed with steel or stainless steel through metallurgical bonding of mixed metallic elements, and the metallurgical bonding is achieved by argon arc welding.

[0009] The alloy of mixed metallic elements has the following chemical composition: copper content of 20% to 80%, nickel content of 1% to 70%, iron content of 1% to 20%, carbon content of 0.001% to 0.2%, cobalt content of 0.02% to 0.3%, manganese content of 0.5% to 2.0%, and zinc content of 0.1% to 30%.

[0010] The above-mentioned method for welding titanium and its alloys to steel or stainless steel, further...

[0011] Step 1: Weld the mixed element alloy welding wire onto the surface of steel or stainless steel to obtain a welded joint with a mixed element alloy as a transition layer.

[0012] Step 2: On the surface with the mixed element alloy as the transition layer obtained in Step 1, the welding quality of the transition layer is confirmed by PT method, and the absence of defects is considered as qualified.

[0013] Step 3: On the surface of the transition layer that has passed the inspection in Step 2, titanium and its alloy welding wires are welded using manual argon arc welding. The welding thickness is determined according to the required thickness of the titanium alloy.

[0014] Step 4: After completing the argon arc welding in Step 3 and ensuring the titanium alloy layer thickness meets the requirements, polish and grind the titanium alloy layer, then perform PT inspection again. If there are no defects, it is considered qualified. Then perform UT inspection to confirm that there is no delamination at the welded area.

[0015] Furthermore, in the above-mentioned welding method of titanium and its alloys to steel or stainless steel, in step one, the thickness of the alloy of mixed metal elements is not less than 2 mm.

[0016] The above-mentioned welding method for titanium and its alloys to steel or stainless steel further includes the following process parameters for argon arc welding of the transition layer alloy to carbon steel or stainless steel: welding current 110A~180A, welding voltage 12V~20V, welding speed 10cm / min~20cm / min, and argon flow rate 10 L / min~20L / min.

[0017] The above-mentioned welding method for titanium and its alloys to steel or stainless steel further includes the following process parameters for argon arc welding of titanium and its alloys to the transition layer: welding current 90A~140A, welding voltage 10V~20V, welding speed 14cm / min~20cm / min, and argon flow rate 10 L / min~20L / min.

[0018] The above-mentioned welding method of titanium and its alloys with steel or stainless steel further includes the steel or stainless steel being: SA516Gr70 / SA516Gr60 / Q345R / Q245R / S30403(8) / S31603(8) or corresponding forging plates.

[0019] The above-mentioned welding method of titanium and its alloys to steel or stainless steel further specifies that the titanium and its alloys are: TA1 / TA2 / TA8 / TA9 / TA10 or SB265Gr.1 / SB265Gr.2 / SB265Gr.7 / SB265Gr.11 plates.

[0020] Compared with existing technologies, this invention employs a manual argon arc welding process, which is simple and easy to implement. The mixed-element alloy welding wire used for the transition layer contains no Be or Ti components, and the welding process requires no special control, preventing the formation of brittle intermetallic compounds. It can weld and connect titanium alloys of different shapes and complex curved surfaces with composite materials of steel or stainless steel. Attached Figure Description

[0021] Figure 1 This is a cross-sectional schematic diagram of the present invention;

[0022] Among them, 1-titanium alloy layer, 2-mixed element alloy transition layer, 3-steel or stainless steel layer. Detailed Implementation

[0023] The invention will be further described with reference to the accompanying drawings.

[0024] like Figure 1 The invention illustrates a welding method for titanium and its alloys with steel or stainless steel, wherein the titanium and its alloys are metallurgically bonded to the steel or stainless steel through an alloy of mixed metallic elements, and the metallurgical bond is achieved by argon arc welding.

[0025] The alloy of mixed metallic elements has the following chemical composition: copper content of 20% to 80%, nickel content of 1% to 70%, iron content of 1% to 20%, carbon content of 0.001% to 0.2%, cobalt content of 0.02% to 0.3%, manganese content of 0.5% to 2.0%, and zinc content of 0.1% to 30%.

[0026] The specific implementation steps are as follows:

[0027] Step 1: Using manual argon arc welding, weld the mixed element alloy welding wire (2) onto the surface of steel or stainless steel (3) with a welding thickness of 2mm to obtain a welded joint with a mixed element alloy as a transition layer. At this time, the alloy composition detection value of the welded transition layer is:

[0028] Fe: 0.8%, Mn: 1.0%, Ni: 31.0%, Cu: 67.1%, others: 0.1%.

[0029] Step 2: On the surface with the mixed element alloy as the transition layer obtained in Step 1, the welding quality of the transition layer is confirmed by PT method, and the absence of defects is considered as qualified;

[0030] Step 3: On the surface of the transition layer that has passed the inspection in Step 2, the titanium and its alloy (1) welding wire is welded by manual argon arc welding. The welding thickness is determined according to the thickness requirement of the titanium alloy.

[0031] Step 4: After completing the argon arc welding in Step 3 and ensuring the titanium alloy layer thickness meets the requirements, polish and grind the titanium alloy layer, then perform PT inspection again. If there are no defects, it is considered qualified. Then perform UT inspection to confirm that there is no delamination at the welded area.

[0032] In step one: the steel or stainless steel is: SA 516Gr70 / SA516Gr60 / Q345R / Q245R / S30403(8) / S31603(8) or the corresponding forging plate.

[0033] In step three: titanium and its alloys are: TA1 / TA2 / TA8 / TA9 / TA10 or SB265Gr.1 / SB265Gr.2 / SB265Gr.7 / SB265Gr.11 plates.

Claims

1. A method of welding titanium and its alloys to steel or stainless steel, characterized in that: Titanium and its alloys are metallurgically combined with steel or stainless steel through metal mixed element alloy welding wire, and the metallurgical combination is realized through the welding mode of argon arc welding; The metal mixed element alloy welding wire has the following chemical component content: the content of copper is 20%-80%, the content of nickel is 1%-70%, the content of iron is 1%-20%, the content of carbon is 0.001%-0.2%, the content of cobalt is 0.02%-0.3%, the content of manganese is 0.5%-2.0%, and the content of zinc is 0.1%-30%. The specific steps are as follows: Step one: the metal mixed element alloy welding wire is welded on the surface of steel or stainless steel to obtain a welded joint with a mixed element alloy transition layer; Step two: the transition layer is welded by using the PT mode to confirm the welding quality of the transition layer, and no defect is qualified; Step three: the titanium and its alloys are welded by using the manual argon arc welding mode on the surface of the transition layer qualified in step two, and the welding thickness is determined according to the thickness of the titanium alloy; Step four: after the argon arc welding in step three is completed and the thickness of the titanium alloy layer meets the needs, the titanium alloy layer is polished and ground, and then the PT inspection is performed again, and no defect is qualified, and then the UT inspection is performed to confirm that the welding position is qualified without delamination.

2. The method of welding titanium and its alloys to steel or stainless steel according to claim 1, characterized in that: In step one, the thickness of the metal mixed element alloy transition layer is not less than 2 mm.

3. The method of welding titanium and its alloys to steel or stainless steel according to claim 1, characterized in that: The process parameters of the argon arc welding of the transition layer alloy and the carbon steel or stainless steel are as follows: the welding current is 110A-180A, the welding voltage is 12V-20V, the welding speed is 10cm / min-20cm / min, and the argon gas flow is 10 L / min-20L / min.

4. The method of welding titanium and its alloys to steel or stainless steel according to claim 1, characterized in that: The process parameters of the argon arc welding of the titanium and its alloys and the transition layer are as follows: the welding current is 90A-140A, the welding voltage is 10V-20V, the welding speed is 14cm / min-20cm / min, and the argon gas flow is 10 L / min-20L / min.

5. The method of welding titanium and its alloys to steel or stainless steel according to claim 1, characterized in that: The steel or stainless steel is SA 516Gr70 / SA516Gr60 / Q345R / Q245R / S30403 / S31603 or corresponding forged plate material.

6. The method of welding titanium and its alloys to steel or stainless steel according to claim 1, characterized in that: The titanium and its alloys are TA1 / TA2 / TA8 / TA9 / TA10 or SB265Gr.1 / SB265Gr.2 / SB265Gr.7 / SB265Gr.11 plate material.

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