High-entropy alloy and stainless steel sheet electron beam welding method

Abstract

The present application provides a high-entropy alloy and stainless steel metal plate electron beam welding method, which belongs to the technical field of vacuum welding, and solves the problems of stress concentration, heat residence time period and weld crack prone in the welding process of high-entropy alloy and stainless steel, comprising the following steps: step 1, determining the to-be-welded interface of high-entropy alloy and stainless steel metal plate; step 2, workpiece assembly; step 3, vacuum welding; step 4, completing welding and heat preservation, and taking out the welded workpiece. The present application has the advantages of simple process and easy implementation, compared with adding an intermediate metal layer or complex welding process control, the arc-shaped weld design of the present application is easy to process and implement, suitable for large-scale industrial production, and has high practicality and popularization value.

Description

Technical Field

[0001] This invention relates to an electron beam welding method for high-entropy alloys and stainless steel metal plates, belonging to the field of vacuum welding technology. Background Technology

[0002] In modern manufacturing, electron beam welding technology has been widely used to join various metallic materials. With the emergence of high-entropy alloys and their applications in engineering, research on related dissimilar metal welding technologies has become an important emerging research field. High-entropy alloys are ideal structural materials due to their excellent mechanical properties and corrosion resistance, but their production costs are high and production cycles are long. Therefore, exploring the structural design of welded joints between high-entropy alloys and other metals can further reduce product costs, improve production efficiency, and enhance product competitiveness, showing significant application potential in aerospace, automotive, and energy fields.

[0003] High-entropy alloys have attracted much attention due to their excellent comprehensive properties, especially the nanotwins and work hardening effects generated during deformation, which give them outstanding mechanical properties at both room temperature and low temperatures. They exhibit significant advantages in resistance to hydrogen embrittlement and fracture toughness, making them suitable for components requiring extreme low-temperature resistance. However, their complex manufacturing process and high cost limit their widespread application. In contrast, stainless steel possesses good corrosion resistance and mechanical properties, and is widely used in chemical, aerospace, and marine industries, offering a more economical price and similarly good low-temperature performance. Combining high-entropy alloys with stainless steel to manufacture structural components offers the advantage of higher cost-effectiveness for stainless steel, while high-entropy alloys can provide superior performance and environmental corrosion resistance in critical areas. This approach optimizes performance while reducing costs, further promoting the application of high-entropy alloys in industrial settings.

[0004] High-entropy alloys and stainless steel differ significantly in their thermophysical properties and material composition, particularly in their coefficients of thermal expansion and specific heat capacity. This makes them prone to stress concentration during welding, and the compositional differences can also lead to poor metallurgical compatibility. Therefore, during electron beam welding, the combined effect of these factors can cause stress concentration in the weld area, leading to crack formation and reducing the mechanical properties and reliability of the weld joint. Furthermore, electron beam welding involves a rapid cooling rate, and high-entropy alloys are highly sensitive to cooling rates; rapid cooling can trigger weld cracks. Therefore, it is essential to control the cooling process by appropriately extending the high-temperature dwell time of the weld to suppress welding stress and reduce cracking. Slow cooling is generally achieved by reducing the welding speed. Improving metallurgical compatibility typically involves adding metal layers, which requires extensive process exploration and material testing, making the process complex and impractical. To address this, the present invention proposes an electron beam welding method for high-entropy alloys and stainless steel plates. By employing an arc-shaped structure, the method effectively alleviates stress concentration, increases the high-temperature dwell time of the weld, reduces the cooling rate, and improves the weld performance. At the same time, the mechanically stabilizing structure also enhances the reliability of the weld. Summary of the Invention

[0005] This invention addresses the problems of stress concentration, short heat dwell time, and easy cracking in the weld during the welding of high-entropy alloys and stainless steel. It proposes an electron beam welding method for high-entropy alloys and stainless steel plates, specifically including:

[0006] Step 1: Prepare high-entropy alloy and stainless steel metal plates of the same size, and process a continuous arc-shaped welding interface on the high-entropy alloy and stainless steel metal plates.

[0007] Step 2: Grind the interface to be welded with sandpaper, and then perform ultrasonic cleaning on the ground high-entropy alloy and stainless steel metal plates. Wipe the ultrasonically cleaned high-entropy alloy and stainless steel metal plates with organic solvent, and blow dry immediately after wiping.

[0008] Step 3: Align and assemble the high-entropy alloy and stainless steel metal plates after wiping them. Fix the assembled high-entropy alloy and stainless steel metal plates on the welding fixture and place them in the vacuum chamber of the electron beam welding machine. Turn on the multi-stage vacuum system to evacuate the vacuum until the pressure in the vacuum chamber of the electron beam welding machine reaches the preset value.

[0009] Step 4: Turn on the electron gun high voltage system, adjust the focusing current, position the focusing position on the flat plate surface, select the corresponding welding parameters, and control the electron beam to weld the high entropy alloy and stainless steel metal plate along the arc weld seam. After welding, keep it warm in the vacuum chamber.

[0010] Step 5: After the heat preservation is completed, remove the workpiece and complete the electron beam welding of the high-entropy alloy and stainless steel.

[0011] Preferably, in step 1, each adjacent semi-circular arc interface between the high-entropy alloy and the stainless steel metal plate is tangent, and the arc-shaped interfaces to be welded between the high-entropy alloy and the stainless steel metal plate have the same dimensions.

[0012] Preferably, in step 2, the sandpaper used for polishing has a mesh size of 1000-2000, the ultrasonic cleaning frequency is 20kHz, the cleaning time is 5 minutes, and the organic solvent is petroleum ether.

[0013] Preferably, the preset pressure value in step 3 is 5×10 -2 Pa.

[0014] Preferably, in step 4, the welding voltage is 60kV, the welding current is 5-20mA, and the holding time is 15min.

[0015] The beneficial effects of this invention are:

[0016] (1) This invention is suitable for welding high-entropy alloys and stainless steel with a thickness of 2-8mm. By adopting an arc weld design, compared with a straight weld, the arc weld significantly increases the contact area of ​​the joint interface, making the welded part more solid and improving the strength and stability of the welded joint.

[0017] (2) The full-curve structure of the arc weld helps to disperse the stress generated during the welding process. Compared with the traditional straight weld, the arc weld can naturally guide the stress distribution, thereby avoiding stress concentration caused by the difference in thermophysical properties of dissimilar metals and reducing the risk of crack formation.

[0018] (3) The arc-shaped structure of the present invention creates a mechanical stabilizing effect in the weld, improving the crack resistance and service reliability of the weld. Even if cracks occur locally in the joint, the curved weld can limit the propagation of the cracks and enhance the crack resistance of the weld. In this way, even if minor defects occur, the joint can still maintain its basic connection function, increasing safety and reliability.

[0019] (4) The process of the present invention is simple and easy to implement. Compared with the addition of an intermediate metal layer or complex welding process control, the arc weld design of the present invention is easy to process and implement, and is suitable for large-scale industrial production. It has high practicality and promotion value. Attached Figure Description

[0020] Figure 1 A schematic flowchart of an electron beam welding method for high-entropy alloys and stainless steel plates provided by the present invention;

[0021] Figure 2 This is an assembly diagram illustrating the electron beam welding process between high-entropy alloys and stainless steel provided by the present invention.

[0022] Figure 3 A detailed dimension drawing of the arc weld between high-entropy alloy and stainless steel, measuring 150mm × 40mm × 2mm, provided for this invention;

[0023] Figure 4 A detailed dimension drawing of the arc weld between high entropy alloy and stainless steel with dimensions of 300mm×80mm×4mm provided for this invention;

[0024] Figure 5 The present invention provides a detailed dimension drawing of an arc-shaped weld seam of high-entropy alloy and stainless steel with dimensions of 600mm×160mm×6mm. Detailed Implementation

[0025] Specific implementation method one: Combining Figure 1-3 This implementation method is described as follows: Figure 1 As shown, the steps of the electron beam welding method for high-entropy alloys and stainless steel plates described in this embodiment include:

[0026] S1: Determine the welding interface between the high-entropy alloy and the stainless steel sheet;

[0027] In this embodiment, a high-entropy alloy and stainless steel metal plate with dimensions of 150mm × 40mm × 2mm is used, such as Figure 3 As shown, a semi-arc interface with a major axis of 10mm and a minor axis of 5mm is machined on the interface to be welded. Each adjacent semi-arc interface between the high-entropy alloy and the stainless steel metal plate is tangent. The arc interface dimensions of the high-entropy alloy and the stainless steel metal plate are completely consistent. The mating surfaces of the two plates after processing should match each other and be smooth and flat. For different sizes of plates, the dimensions of the arc interface can be adjusted accordingly.

[0028] This embodiment adopts an arc-shaped weld design, which significantly increases the contact area of ​​the joint interface compared to a straight weld, making the welded part more robust and improving the strength and stability of the welded joint.

[0029] S2: Workpiece assembly;

[0030] S201: Use 1000-2000# sandpaper to polish the interface to be welded to remove contaminants such as oxides and rust until the interface is bright.

[0031] S202: Perform ultrasonic cleaning on the polished high-entropy alloy and stainless steel plates to be welded. The ultrasonic cleaning frequency is 20kHz and the cleaning time is 5 minutes to remove contaminants such as oil and sewage stains. Then wipe the interface to be welded with petroleum ether or other organic solvents and blow dry immediately after wiping.

[0032] S203: As Figure 2 As shown, the wiped high-entropy alloy and stainless steel metal plates are assembled to ensure that the interfaces to be welded on the metal plates are aligned and overlapped.

[0033] S3: Vacuum welding;

[0034] S301: The assembled high-entropy alloy and stainless steel metal plates are clamped and fixed on the welding fixture. After fixing, the fixture and metal plates are placed in the vacuum chamber of the electron beam welding machine, and the multi-stage vacuum system is turned on to evacuate.

[0035] S302: When the vacuum level of the vacuum chamber reaches 5×10 -2 At Pa, turn on the electron gun high voltage system, adjust the focusing current, position the focusing position on the flat plate surface, select appropriate welding parameters, and control the electron beam to weld high-entropy alloys and stainless steel along the arc weld seam.

[0036] In this embodiment, the full-curve structure of the arc-shaped weld helps to disperse the stress generated during welding. Compared to traditional straight welds, the arc-shaped weld can naturally guide stress distribution, thereby avoiding stress concentration problems caused by differences in the thermophysical properties of dissimilar metals, reducing the risk of crack formation. Furthermore, the arc-shaped structure creates a mechanical stabilizing effect within the weld, improving its crack resistance and service reliability. Even if localized cracks occur in the joint, the curved weld can limit crack propagation, enhancing the weld's crack resistance. Thus, even with minor defects, the joint can still maintain its basic connection function, increasing safety and reliability.

[0037] S4: Complete welding and maintain heat, then remove the welded workpiece;

[0038] After welding, the workpiece is kept in a vacuum chamber for 10 to 20 minutes before being removed.

[0039] Specific Implementation Method Two: Combining Figure 1 , Figure 2 and Figure 4 This embodiment will be described as follows: Figure 1 As shown, the steps of the electron beam welding method for high-entropy alloys and stainless steel plates described in this embodiment include:

[0040] S1: Determine the welding interface between the high-entropy alloy and the stainless steel sheet;

[0041] This embodiment prepares a high-entropy alloy and stainless steel metal plate with dimensions of 300mm × 80mm × 4mm, such as Figure 4 As shown, a semi-arc interface with a major axis of 40mm and a minor axis of 20mm is machined on the interface to be welded. Each adjacent semi-arc interface is tangent to each other. The arc interface dimensions of the two plates are completely consistent. The mating surfaces of the two plates after machining match each other and are smooth and flat.

[0042] S2: Workpiece assembly;

[0043] S201: Use 1000-2000# sandpaper to polish the interface to be welded to remove contaminants such as oxides and rust until the interface is bright.

[0044] S202: Perform ultrasonic cleaning on the polished high-entropy alloy and stainless steel plates to be welded. The ultrasonic cleaning frequency is 20kHz and the cleaning time is 5 minutes to remove contaminants such as oil and sewage stains. Then wipe the interface to be welded with petroleum ether or other organic solvents and blow dry immediately after wiping.

[0045] S203: As Figure 2 As shown, the wiped high-entropy alloy and stainless steel metal plates are assembled to ensure that the interfaces to be welded on the metal plates are aligned and overlapped.

[0046] S3: Vacuum welding;

[0047] S301: The assembled high-entropy alloy and stainless steel metal plates are clamped and fixed on the welding fixture. After fixing, the fixture and metal plates are placed in the vacuum chamber of the electron beam welding machine, and the multi-stage vacuum system is turned on to evacuate.

[0048] S302: When the vacuum level of the vacuum chamber reaches 5×10 -2 At Pa, turn on the electron gun high voltage system, adjust the focusing current, position the focusing position on the flat plate surface, set the welding voltage to 60kV and the welding current to 5-20mA, ensure that the weld is fully penetrated and there is no obvious concavity or convexity, and control the electron beam to weld high-entropy alloys and stainless steel along the arc weld.

[0049] S4: Complete welding and maintain heat, then remove the welded workpiece;

[0050] After welding, the workpiece is kept at a temperature of 15 minutes in a vacuum chamber before being removed.

[0051] Specific implementation method three: Combining Figure 1 , Figure 2 and Figure 5 This embodiment will be described as follows: Figure 1 As shown, the steps of the electron beam welding method for high-entropy alloys and stainless steel plates described in this embodiment include:

[0052] S1: Determine the welding interface between the high-entropy alloy and the stainless steel sheet;

[0053] This embodiment prepares a high-entropy alloy and stainless steel metal plate with dimensions of 600mm × 160mm × 6mm, such as Figure 5 As shown, a semi-arc interface with a major axis of 40mm and a minor axis of 20mm is machined on the interface to be welded. Each adjacent semi-arc interface is tangent to each other. The arc interface dimensions of the two plates are completely consistent. The mating surfaces of the two plates after machining match each other and are smooth and flat.

[0054] S2: Workpiece assembly;

[0055] S201: Use 1000-2000# sandpaper to polish the interface to be welded to remove contaminants such as oxides and rust until the interface is bright.

[0056] S202: Perform ultrasonic cleaning on the polished high-entropy alloy and stainless steel plates to be welded. The ultrasonic cleaning frequency is 20kHz and the cleaning time is 5 minutes to remove contaminants such as oil and sewage stains. Then wipe the interface to be welded with petroleum ether or other organic solvents and blow dry immediately after wiping.

[0057] S203: As Figure 2 As shown, the wiped high-entropy alloy and stainless steel metal plates are assembled to ensure that the interfaces to be welded on the metal plates are aligned and overlapped.

[0058] S3: Vacuum welding;

[0059] S301: The assembled high-entropy alloy and stainless steel metal plates are clamped and fixed on the welding fixture. After fixing, the fixture and metal plates are placed in the vacuum chamber of the electron beam welding machine, and the multi-stage vacuum system is turned on to evacuate.

[0060] S302: When the vacuum level of the vacuum chamber reaches 5×10 -2 At Pa, turn on the electron gun high voltage system, adjust the focusing current, position the focusing position on the flat plate surface, set the welding voltage to 60kV and the welding current to 5-20mA, ensure that the weld is fully penetrated and there is no obvious concavity or convexity, and control the electron beam to weld high-entropy alloys and stainless steel along the arc weld.

[0061] S4: Complete welding and maintain heat, then remove the welded workpiece;

[0062] After welding, the workpiece is kept at a temperature of 15 minutes in a vacuum chamber before being removed.

[0063] In summary, the present invention has a simple process and is easy to implement. Compared with adding an intermediate metal layer or controlling the welding process through complex means, the arc weld design of the present invention is easy to process and implement, and is suitable for large-scale industrial production. It has high practicality and promotion value.

[0064] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make some modifications or alterations to the above-disclosed technical content to create equivalent embodiments without departing from the scope of the present invention. Any simple modifications, equivalent substitutions, and improvements made to the above embodiments without departing from the scope of the present invention, based on the technical essence of the present invention and within the spirit and principles of the present invention, shall still fall within the protection scope of the present invention.

Claims

1. A method for electron beam welding of a high-entropy alloy to a stainless steel metal plate, characterized in that, The steps of the electron beam welding method for high-entropy alloys and stainless steel plates include: Step 1: Prepare high-entropy alloy and stainless steel metal plates of the same size, and process a continuous arc-shaped welding interface on the high-entropy alloy and stainless steel metal plates. Step 1: Each adjacent semi-circular arc interface between the high-entropy alloy and the stainless steel metal plate is tangent, and the arc-shaped welding interface dimensions of the high-entropy alloy and the stainless steel metal plate are consistent, in order to avoid stress concentration caused by the difference in thermophysical properties of dissimilar metals, reduce the risk of crack formation, and even if cracks occur, limit the propagation of cracks and enhance the crack resistance of the weld. Step 2: Grind the interface to be welded with sandpaper, and then perform ultrasonic cleaning on the ground high-entropy alloy and stainless steel metal plates. Wipe the ultrasonically cleaned high-entropy alloy and stainless steel metal plates with organic solvent, and blow dry immediately after wiping. Step 3: Align and assemble the high-entropy alloy and stainless steel metal plates after wiping them. Fix the assembled high-entropy alloy and stainless steel metal plates on the welding fixture and place them in the vacuum chamber of the electron beam welding machine. Turn on the multi-stage vacuum system to evacuate the vacuum until the pressure in the vacuum chamber of the electron beam welding machine reaches the preset value. Step 4: Turn on the electron gun high voltage system, adjust the focusing current, position the focusing position on the flat plate surface, select the corresponding welding parameters, and control the electron beam to weld the high entropy alloy and stainless steel metal plate along the arc weld seam. After welding, keep it warm in the vacuum chamber. In step 4, the welding voltage is 60 kV, the welding current is 5~20mA, and the holding time is 15min. Step 5: After the heat preservation is completed, remove the workpiece and complete the electron beam welding of the high-entropy alloy and stainless steel.

2. The electron beam welding method for high-entropy alloys and stainless steel plates according to claim 1, characterized in that, In step 2, the sandpaper used for polishing is 1000-2000 grit, the ultrasonic cleaning frequency is 20kHz, the cleaning time is 5 minutes, and the organic solvent is petroleum ether.

3. The electron beam welding method for high-entropy alloys and stainless steel plates according to claim 1, characterized in that, The preset pressure value in step 3 is 5×10 -2 Pa.

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