Method for the production of layered alloys based on electric arc additive manufacturing and magnesium alloy components

Abstract

The disclosure provides a layered alloy preparation method based on electric arc additive manufacturing and a magnesium alloy component, and relates to the technical field of electric arc additive manufacturing. The preparation method comprises the following steps: constructing a magnesium alloy model, performing slicing processing on the magnesium alloy model, performing path planning according to the result of the slicing processing, and inputting the parameter result of the path planning into an electric arc additive manufacturing device; preheating a magnesium alloy substrate, and installing a magnesium alloy wire to a wire feeding device; starting the electric arc additive manufacturing device and the wire feeding device, and performing an electric arc additive manufacturing deposition process based on a pulse mode on the magnesium alloy substrate to obtain a formed piece; and air cooling the formed piece to room temperature to obtain a magnesium alloy component; wherein, during the deposition process, the linear rise rate and the linear fall rate of the peak current are 900-1000 A / ms, the pulse peak current is 370-390 A, the pulse base current is 70-90 A, the wire feeding speed in the pulse cycle is 33-36 m / min, and the number of pulse cycles is 1-10. The disclosure can inhibit the formation of pore defects in the magnesium alloy additive manufacturing process.

Description

Technical Field

[0001] This disclosure relates to the field of electric arc additive manufacturing technology, and more specifically, to a method for preparing layered alloys and magnesium alloy components based on electric arc additive manufacturing. Background Technology

[0002] Magnesium alloys are highly promising lightweight materials for aerospace and other fields due to their excellent specific strength, specific stiffness, electromagnetic shielding properties, and recyclability. Currently, their manufacturing mainly relies on casting and deformation processes (such as hot rolling, hot extrusion, and forging). However, deformation processes suffer from high costs, easy oxidation, and difficulty in forming complex structures, while casting processes face challenges such as elemental segregation, coarse grains, and insufficient mechanical properties.

[0003] With the growing demand for high efficiency and high performance in the manufacturing industry, Wire and Arc Additive Manufacturing (WAAM) technology, or arc additive manufacturing for short, has provided a new approach for the preparation of large-size and complex magnesium alloy parts due to its advantages such as high material utilization and fast forming of complex structures.

[0004] Magnesium alloys produced by current electric arc additive manufacturing methods generally suffer from high porosity, which reduces the mechanical properties of the material and makes it difficult to meet industrial requirements.

[0005] It should be noted that the information disclosed in the background section above is only used to enhance the understanding of the background of this disclosure, and therefore may include information that does not constitute prior art known to those skilled in the art. Summary of the Invention

[0006] The purpose of this disclosure is to provide a method for preparing layered alloys based on electric arc additive manufacturing and magnesium alloy components, thereby overcoming, at least to some extent, the problem of porosity defects in magnesium alloy components.

[0007] According to a first aspect of this disclosure, a method for preparing magnesium alloy components based on arc additive manufacturing is provided, comprising: constructing a magnesium alloy model using modeling software, slicing the magnesium alloy model, performing path planning based on the slicing results, and inputting the path planning parameters into an arc additive manufacturing equipment; preheating a magnesium alloy substrate and installing magnesium alloy wire coils into a wire feeding device; starting the arc additive manufacturing equipment and the wire feeding device under a protective gas atmosphere, and performing a pulse-mode arc additive manufacturing deposition process on the magnesium alloy substrate to obtain a shaped part; and air-cooling the shaped part to room temperature to obtain a magnesium alloy component; wherein, in the pulse-mode arc additive manufacturing deposition process, the linear rise and fall rate of the peak current is 900~1000 A / ms, the pulse peak current is 370~390 A, the pulse base current is 70~90 A, the wire feeding speed within the pulse cycle is 33~36 m / min, and the number of pulse cycles is 1~10.

[0008] Optionally, the slice type in the slicing process is a planar slice.

[0009] Optionally, path planning includes a centerline path.

[0010] Optionally, preheating the magnesium alloy substrate includes preheating the magnesium alloy substrate using a heating plate.

[0011] Optionally, the preheating temperature is 120~180℃.

[0012] Optionally, a shielding gas can be introduced through the coaxial interface of the welding torch.

[0013] Optionally, the protective gas is argon, and the flow rate is 20 L / min to 25 L / min.

[0014] Optionally, the diameter of the magnesium alloy wire is 1.2 mm.

[0015] Alternatively, the magnesium alloy component may be an AZ80 magnesium alloy component, an AZ91 magnesium alloy component, or a VW82 magnesium alloy component.

[0016] According to a second aspect of this disclosure, a magnesium alloy component is provided, which is prepared using any of the above-described methods for preparing magnesium alloy components based on arc additive manufacturing.

[0017] In the embodiments of this disclosure, by precisely and collaboratively controlling multiple process parameters such as the linear rise and fall rate of the peak current within the pulse cycle, the pulse peak current, the pulse base current, the wire feed speed within the pulse cycle, and the number of pulse cycles, the dynamic behavior of the molten pool can be actively intervened. This allows for effective control of the molten pool stirring intensity, flow pattern, and solidification process, effectively promoting the escape of gas from the molten pool and suppressing its entrapment, thereby significantly inhibiting the formation of porosity defects during magnesium alloy additive manufacturing. The porosity of magnesium alloy components prepared using the method of this disclosure is significantly reduced, thereby improving the overall performance of the workpiece and solving the problems of high porosity and poor performance of magnesium alloy arc additive components in the prior art.

[0018] It should be understood that the above general description and the following detailed description are exemplary and explanatory only, and are not intended to limit this disclosure. Attached Figure Description

[0019] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this disclosure and, together with the description, serve to explain the principles of this disclosure. It is obvious that the drawings described below are merely some embodiments of this disclosure, and those skilled in the art can obtain other drawings based on these drawings without any inventive effort.

[0020] Figure 1 Metallographic images of magnesium alloy components not prepared using the pulse printing method of this disclosure are schematically shown.

[0021] Figure 2 A schematic diagram of the process principle of electric arc additive manufacturing used in this disclosure is shown.

[0022] Figure 3 A flowchart illustrating a method for preparing magnesium alloy components based on arc additive manufacturing according to an embodiment of the present disclosure is shown.

[0023] Figure 4 A physical image of the magnesium alloy component prepared according to Embodiment 1 of this disclosure is shown.

[0024] Figure 5 Metallographic images of the magnesium alloy component prepared according to Embodiment 1 of this disclosure are shown.

[0025] Figure 6 A physical image of the magnesium alloy component prepared according to Embodiment 2 of this disclosure is shown.

[0026] Figure 7 Metallographic images of the magnesium alloy component prepared according to Embodiment 2 of this disclosure are shown.

[0027] Figure 8 A physical image of the magnesium alloy component prepared according to Embodiment 3 of this disclosure is shown.

[0028] Figure 9 Metallographic images of the magnesium alloy component prepared according to Embodiment 3 of this disclosure are shown. Detailed Implementation

[0029] Exemplary embodiments will now be described more fully with reference to the accompanying drawings. However, these exemplary embodiments can be implemented in many forms and should not be construed as limited to the examples set forth herein; rather, these embodiments are provided to make this disclosure more comprehensive and complete, and to fully convey the concept of the exemplary embodiments to those skilled in the art. The described features, structures, or characteristics can be combined in any suitable manner in one or more embodiments. In the following description, numerous specific details are provided to give a full understanding of embodiments of this disclosure. However, those skilled in the art will recognize that the technical solutions of this disclosure can be practiced with one or more of these specific details omitted, or other methods, processes, steps, etc., can be employed. In other instances, well-known technical solutions are not shown or described in detail to avoid obscuring various aspects of this disclosure.

[0030] Furthermore, the accompanying drawings are merely illustrative of this disclosure and are not necessarily drawn to scale. The same reference numerals in the drawings denote the same or similar parts, and therefore repeated descriptions of them will be omitted. The flowcharts shown in the drawings are merely exemplary illustrations and do not necessarily include all steps. For example, some steps may be broken down, while others may be combined or partially combined; therefore, the actual order of execution may change depending on the specific circumstances.

[0031] Cold metal transition arc additive manufacturing (CMT-WAAM) technology has shown great potential in the preparation of magnesium alloys, but there are still problems in coordinating heat input and cooling rate, which can easily lead to defects such as coarse grains, increased porosity and uneven distribution of the second phase during the additive manufacturing process. Figure 1 The diagram schematically illustrates metallographic images of magnesium alloy components fabricated using several methods. These problems reduce the mechanical properties of the material, making it difficult to meet the current industrial requirements for high strength and high reliability in equipment manufacturing.

[0032] To improve the quality of magnesium alloy components, this disclosure provides a novel method for preparing magnesium alloy components based on arc additive manufacturing.

[0033] First, refer to Figure 2The process principle of arc additive manufacturing used in this embodiment will be explained. Magnesium alloy wire 21 is fed in through wire feeding system 22. Under the atmosphere of protective gas 25 provided by protective gas tank 23, nozzle 24 generates an electric arc 26 in response to the start of power supply 20. During the continuous feeding of magnesium alloy wire 21, a molten pool 27 is formed, and the deposition process of arc additive manufacturing is carried out, finally obtaining magnesium alloy component 28.

[0034] Figure 3 A flowchart illustrating a method for fabricating magnesium alloy components based on arc additive manufacturing according to an embodiment of this disclosure is shown schematically. (Reference) Figure 3 The method for preparing magnesium alloy components based on electric arc additive manufacturing according to the present disclosure may include the following steps: S32. Construct a magnesium alloy model using modeling software, slice the magnesium alloy model, perform path planning based on the slicing results, and input the path planning parameters into the arc additive manufacturing equipment.

[0035] This disclosure does not limit the slicing and path planning operations of the model in the additive manufacturing scenario. It is understood that, through step S32, relevant parameters for arc additive manufacturing of the magnesium alloy can be obtained, and these parameters can be input into the arc additive manufacturing equipment so that the equipment can perform process operations based on these parameters.

[0036] According to some embodiments of this disclosure, the slice type in the slicing process can be a planar slice, and the path planning can include a centerline path.

[0037] S34. Preheat the magnesium alloy substrate and install the magnesium alloy wire coil into the wire feeding device.

[0038] According to some embodiments of this disclosure, a heating plate can be used to preheat a magnesium alloy substrate. Specifically, the preheating temperature can be 120~180°C, for example, 150°C.

[0039] In addition, the diameter of the magnesium alloy wire in this embodiment is 1.2 mm.

[0040] S36. Under a protective gas atmosphere, start the arc additive manufacturing equipment and wire feeding equipment to perform a pulse-mode arc additive manufacturing deposition process on a magnesium alloy substrate to obtain a shaped part.

[0041] In an exemplary embodiment of this disclosure, the protective gas is introduced through the coaxial interface of the welding torch. Specifically, the protective gas is argon, and the flow rate is 20 L / min to 25 L / min.

[0042] In the pulse-mode-based arc additive manufacturing deposition process, the linear rise and fall rate of the peak current is 900~1000A / ms, the pulse peak current is 370~390A, the pulse base current is 70~90A, the wire feed speed within the pulse cycle is 33~36m / min, and the number of pulse cycles is 1~10.

[0043] The rise rate refers to the amount of change in current from the base current to the peak current per unit time, while the fall rate refers to the amount of change in current from the peak current to the base current per unit time.

[0044] S38. Air-cool the formed part to room temperature to obtain a magnesium alloy component.

[0045] The magnesium alloy components produced by this disclosure can be AZ80 magnesium alloy components, AZ91 magnesium alloy components, or VW82 magnesium alloy components.

[0046] Based on the preparation method of the above embodiments, an electric arc is used as a heat source. By precisely coordinating the control of five key process parameters, namely the pulse peak current, the pulse base current, the linear rise rate and fall rate of the peak current, the wire feeding speed within the pulse cycle, and the number of pulse cycles, the active and precise control of the stirring intensity of the molten pool, the solidification rate, and the heat input is achieved. This suppresses the generation of porosity defects from the source and ultimately significantly improves the comprehensive performance of magnesium alloy components.

[0047] By synergistically optimizing the aforementioned multiple parameters, precise control over the arc heat input and its distribution can be achieved. These parameters work together to influence the thermodynamic conditions of the molten pool, regulating its flow characteristics, temperature gradient, and solidification kinetics, promoting bubble escape, and thus significantly suppressing porosity. Ultimately, forming parts with extremely low porosity can be obtained during magnesium alloy additive manufacturing. Furthermore, the embodiments of this disclosure also involve in-situ air cooling of the component after forming to avoid residual stress, deformation, or cracking caused by non-uniform heat dissipation or excessively rapid cooling, further ensuring the uniformity, density, and mechanical properties of the component's microstructure.

[0048] On the one hand, the embodiment of this disclosure sets the pulse peak current to 370~390A, which can achieve rapid melting of the welding wire tip, prepare for subsequent droplet transfer, and at the same time heat and keep the molten pool warm, which helps to promote the fusion process and improve the forming quality.

[0049] On the other hand, in this embodiment, the pulse base current is set to 70~90A, which mainly serves to maintain stable arc combustion and achieve moderate cooling of the molten pool during the pulse interval. This helps to suppress heat accumulation and stabilize the droplet transition process, thereby reducing spatter and porosity formation and further improving the density and uniformity of the deposited layer structure.

[0050] On the other hand, in this embodiment, the wire feeding speed within the pulse cycle is set to 33~36m / min. This wire feeding speed, in coordination with the pulse current parameters, can ensure the stability of the droplet transition frequency, thereby effectively suppressing arc disturbance and molten pool splashing. This is an important process guarantee for obtaining low porosity and high density formed components.

[0051] In addition, in this embodiment, the number of pulse cycles is set to 1 to 10, which can achieve sufficient stirring of the molten pool, thereby effectively promoting the escape of bubbles, reducing porosity, and improving the compactness of the deposited layer.

[0052] This disclosure introduces a pulse mode into the CMT (Cold Metal Transfer) process. The electromagnetic stirring effect generated by the pulse can enhance the fluidity of the molten pool, thereby making the interlayer bonding of the material denser, effectively reducing defects such as porosity and incomplete fusion, and significantly improving the overall performance of magnesium alloy components.

[0053] By precisely coordinating and controlling parameters such as the linear rise / fall rate of the peak current, the pulse peak current, the base current, the wire feed speed within the pulse cycle, and the number of pulse cycles, optimized control of heat input can be achieved. Combined with the stirring behavior of the molten pool and the solidification process under pulse action, this helps promote bubble escape, thereby reducing the formation of porosity defects. During the pulse base phase, the heat input decreases sharply, accelerating molten pool cooling, effectively suppressing the precipitation of coarse second phases, and improving the uniformity of the microstructure. Simultaneously, with effective control of the pulse cycle, the uniformity of elemental distribution within the molten pool can be optimized, mitigating common anisotropy in manufacturing processes and significantly improving the consistency and stability of the formed parts' performance.

[0054] The scheme of Embodiment 1 of this disclosure will be described below.

[0055] Step one involves digitally modeling the AZ80 magnesium alloy component using 3D modeling software. The imported model is then sliced ​​and path-planned. After ensuring the slicing and path simulations are accurate, the model is sent to the arc additive manufacturing equipment for operation. The slicing type in the slicing process is planar slice, and the path planning includes a centerline path.

[0056] Step 2: Preheat the magnesium alloy substrate to 150°C using a heating plate.

[0057] Step 3: Install the AZ80 magnesium alloy coil wire with a diameter of 1.2mm into the wire feeding device, and at the same time, introduce argon gas with a flow rate of 20L / min through the coaxial interface of the welding torch.

[0058] Step four, set the parameters, specifically including: the linear rise rate and fall rate of the peak current are both 900A / ms, the pulse peak current is 370A, the pulse base current is 70A, the wire feeding speed within the pulse cycle is 33m / min, and the number of pulse cycles is 1.

[0059] Step 5: Start the arc additive manufacturing equipment and wire feeding equipment to perform arc additive manufacturing to obtain the shaped part.

[0060] Step 6: Allow the molded part to cool in situ until it reaches room temperature to obtain an AZ80 magnesium alloy component.

[0061] Figure 4 A physical image of a magnesium alloy component prepared according to Embodiment 1 of this disclosure is shown. Figure 4 As can be seen from the example, the AZ80 magnesium alloy component prepared in Example 1 has a dense interlayer bond and is free from defects such as pores and lack of fusion.

[0062] Figure 5 A metallographic image of the magnesium alloy component prepared according to Embodiment 1 of this disclosure is shown. Compared to Figure 1 The internal defects of the AZ80 magnesium alloy component prepared in Example 1 were significantly suppressed, especially the porosity was significantly reduced and the microcracks were almost eliminated. This result is attributed to the effective control of heat input and solidification behavior by the method disclosed herein, thereby successfully obtaining a dense magnesium alloy additive manufacturing component with controllable defects.

[0063] The scheme of Embodiment 2 of this disclosure will be described below.

[0064] Step one involves digitally modeling the AZ91 magnesium alloy component using 3D modeling software. The imported model is then sliced ​​and path-planned. After ensuring the slicing and path simulations are accurate, the model is sent to the arc additive manufacturing equipment for operation. The slicing type in the slicing process is planar slice, and the path planning includes a centerline path.

[0065] Step 2: Preheat the magnesium alloy substrate to 120°C using a heating plate.

[0066] Step 3: Install the AZ91 magnesium alloy coil wire with a diameter of 1.2mm into the wire feeding device, and at the same time introduce argon gas with a flow rate of 25L / min through the coaxial interface of the welding torch.

[0067] Step four, set the parameters, specifically including: the linear rise rate and fall rate of the peak current are both 950A / ms, the pulse peak current is 380A, the pulse base current is 80A, the wire feeding speed within the pulse cycle is 34m / min, and the number of pulse cycles is 5.

[0068] Step 5: Start the arc additive manufacturing equipment and wire feeding equipment to perform arc additive manufacturing to obtain the shaped part.

[0069] Step 6: Allow the molded part to cool in situ until it reaches room temperature to obtain an AZ91 magnesium alloy component.

[0070] Figure 6 A physical image of a magnesium alloy component prepared according to Embodiment 2 of this disclosure is shown. Figure 6 As can be seen from the example, the AZ91 magnesium alloy component prepared in Example 2 has a dense interlayer bond and is free from defects such as pores and lack of fusion.

[0071] Figure 7 A metallographic image of the magnesium alloy component prepared according to Embodiment 2 of this disclosure is shown. Compared to Figure 1 In Example 2, the internal defects of the AZ91 magnesium alloy component were significantly suppressed, especially the porosity was significantly reduced and the microcracks were almost eliminated. This result is attributed to the effective control of heat input and solidification behavior by the method disclosed herein, thereby successfully obtaining a dense magnesium alloy additive manufacturing component with controllable defects.

[0072] The scheme of Embodiment 3 of this disclosure will be described below.

[0073] Step one involves digitally modeling the VW82 magnesium alloy component using 3D modeling software. The imported model is then sliced ​​and path-planned. After ensuring the slicing and path simulations are accurate, the model is sent to the arc additive manufacturing equipment for operation. The slicing type in the slicing process is planar slice, and the path planning includes a centerline path.

[0074] Step 2: Preheat the magnesium alloy substrate to 180°C using a heating plate.

[0075] Step 3: Install the 1.2mm diameter VW82 magnesium alloy wire coil into the wire feeding device, and simultaneously introduce argon gas at a flow rate of 20L / min through the coaxial interface of the welding torch.

[0076] Step four, set the parameters, specifically including: the linear rise rate and fall rate of the peak current are both 1000A / ms, the pulse peak current is 390A, the pulse base current is 90A, the wire feeding speed within the pulse cycle is 36m / min, and the number of pulse cycles is 10.

[0077] Step 5: Start the arc additive manufacturing equipment and wire feeding equipment to perform arc additive manufacturing to obtain the shaped part.

[0078] Step 6: Allow the molded part to cool in situ until it reaches room temperature to obtain a VW82 magnesium alloy component.

[0079] Figure 8 A physical image of the magnesium alloy component prepared according to Embodiment 3 of this disclosure is shown. Figure 8 As can be seen from the example, the VW82 magnesium alloy component prepared in Example 3 has a dense interlayer bond and is free from defects such as pores and lack of fusion.

[0080] Figure 9A metallographic image of the magnesium alloy component prepared according to Embodiment 3 of this disclosure is shown. Compared to Figure 1 In Example 3, the internal defects of the VW82 magnesium alloy component were significantly suppressed, especially the porosity was significantly reduced and the microcracks were almost eliminated. This result is attributed to the effective control of heat input and solidification behavior by the method disclosed herein, thereby successfully obtaining a dense magnesium alloy additive manufacturing component with controllable defects.

[0081] It should be noted that although the steps of the method in this disclosure are described in a specific order in the accompanying drawings, this does not require or imply that the steps must be performed in that specific order, or that all the steps shown must be performed to achieve the desired result. Additional or alternative steps may be omitted, multiple steps may be combined into one step, and / or a step may be broken down into multiple steps.

[0082] Furthermore, the above figures are merely illustrative of the processes included in the method according to exemplary embodiments of this disclosure and are not intended to be limiting. It is readily understood that the processes shown in the above figures do not indicate or limit the temporal order of these processes. Additionally, it is readily understood that these processes may be executed synchronously or asynchronously, for example, in multiple modules.

[0083] Other embodiments of this disclosure will readily occur to those skilled in the art upon consideration of the specification and practice of the disclosure herein. This application is intended to cover any variations, uses, or adaptations of this disclosure that follow the general principles of this disclosure and include common knowledge or customary techniques in the art not disclosed herein. The specification and examples are to be considered exemplary only, and the true scope and spirit of this disclosure are indicated by the claims.

[0084] It should be understood that this disclosure is not limited to the precise structures described above and shown in the accompanying drawings, and various modifications and changes can be made without departing from its scope. The scope of this disclosure is limited only by the appended claims.

Claims

1. A method for preparing magnesium alloy components based on arc additive manufacturing, characterized in that, include: A magnesium alloy model is constructed using modeling software, the magnesium alloy model is sliced, path planning is performed based on the slicing results, and the path planning parameters are input into the arc additive manufacturing equipment. The magnesium alloy substrate is preheated, and the magnesium alloy wire is installed into the wire feeding device. Under a protective gas atmosphere, the arc additive manufacturing equipment and the wire feeding equipment are started to perform a pulse-mode arc additive manufacturing deposition process on the magnesium alloy substrate to obtain a shaped part. The formed part is air-cooled to room temperature to obtain a magnesium alloy component; In the pulse-mode-based arc additive manufacturing deposition process, the linear rise and fall rate of the peak current is 900~1000A / ms, the pulse peak current is 370~390A, the pulse base current is 70~90A, the wire feed speed within the pulse cycle is 33~36m / min, and the number of pulse cycles is 1~10.

2. The method for preparing magnesium alloy components according to claim 1, characterized in that, The slice type in the slicing process is planar slice.

3. The method for preparing magnesium alloy components according to claim 1, characterized in that, Path planning includes centerline paths.

4. The method for preparing magnesium alloy components according to claim 1, characterized in that, Preheating the magnesium alloy substrate includes: The magnesium alloy substrate is preheated using a heating plate.

5. The method for preparing magnesium alloy components according to claim 4, characterized in that, The preheating temperature is 120~180℃.

6. The method for preparing magnesium alloy components according to claim 1, characterized in that, The protective gas is introduced through the coaxial interface of the welding torch.

7. The method for preparing magnesium alloy components according to claim 1 or 6, characterized in that, The protective gas is argon, and the flow rate is 20L / min to 25L / min.

8. The method for preparing magnesium alloy components according to claim 1, characterized in that, The diameter of the magnesium alloy wire is 1.2 mm.

9. The method for preparing magnesium alloy components according to claim 1, characterized in that, The magnesium alloy component is an AZ80 magnesium alloy component, an AZ91 magnesium alloy component, or a VW82 magnesium alloy component.

10. A magnesium alloy component, characterized in that, The magnesium alloy component was prepared using the method for preparing magnesium alloy components based on electric arc additive manufacturing as described in any one of claims 1 to 9.

Images