A method of integrated electric arc additive manufacturing a through-part and a through-part

Abstract

The application relates to a method for integrally manufacturing an electric arc additive manufacturing through member and the through member, and belongs to the electric arc additive manufacturing field.The method comprises the following steps: according to a three-dimensional model diagram of the through member, electric arc additive manufacturing is carried out by using low-alloy high-strength steel wire materials to obtain a through member with consistent structure and size of the three-dimensional model diagram; the through member comprises an integrally-formed through member body and flanges connected to two ends of the through member body.The method can integrally manufacture a through member with a complex shape, and can additionally manufacture a certain width of flange or skirt at the connecting position of the manufactured through member and a connecting plate, so that when the through member is connected with the connecting plate, the corner weld connection at the connecting plate can be changed into flat weld connection, the welding difficulty during the connection of the through member is greatly reduced, and the stress change caused by the asymmetric welding of the corner weld is reduced.

Description

Technical Field

[0001] This invention relates to the field of electric arc additive manufacturing technology, and in particular to a method for integrated electric arc additive manufacturing of a through-hole component and the through-hole component itself. Background Technology

[0002] With the development of the shipbuilding industry and the increasing demands for maritime rights, higher requirements have been placed on the material properties and structural component manufacturing processes of ships and marine engineering platforms. Among these, through-hole components are mainly used in the shipbuilding field for pressure or non-pressure pipeline connections. They are connecting components between pipelines and ships to facilitate the flow of liquid or gas media, enabling various pipelines to drain, transport, collect, or vent air.

[0003] However, the current manufacturing process for through-hole components still mainly relies on machining of forgings to reduce material usage. When connecting through-hole components to plates or annular pipes, the plates or annular pipes must first be cut and then connected to the through-hole components with fillet welds. This process has problems such as long construction time and low manufacturing accuracy. In particular, it is difficult to process ultra-thick pipe structures and it is difficult to control the accuracy of butt welds. Furthermore, asymmetrical fillet welds can easily cause stress changes. Summary of the Invention

[0004] Based on the above analysis, the present invention aims to provide a method and a through-hole component for integrated arc additive manufacturing, in order to solve the problems of high welding difficulty and easy induction of welding stress when the through-hole component manufactured by traditional methods is connected to the connecting plate.

[0005] On one hand, embodiments of the present invention provide a method for integrated arc additive manufacturing of a through-hole component, comprising: based on a three-dimensional model drawing of the through-hole component, arc additive manufacturing is performed using low-alloy high-strength steel wire to obtain a through-hole component with structural dimensions consistent with the three-dimensional model drawing; the through-hole component includes an integrally formed through-hole component body and flanges connected to both ends of the through-hole component body; wherein, the low-alloy high-strength steel wire comprises, by mass percentage: C: 0.03~0.10%, Si: 0.4~0.8%, Mn: 1.50~2.20%, Ni: 2.7~3.5%, Cr: 0.50~0.80%, Mo: 0.50~1.00%, V: ≤0.001%, Ti: ≤0.05%, Sn: 0.01~0.03%, Cu: ≤0.015%, P: ≤0.008%, S: ≤0.008%, O: ≤0.005%, N: ≤0.005%, H: ≤0.001%, with Fe as the balance.

[0006] Furthermore, based on the three-dimensional model of the through-hole component, arc additive manufacturing is performed using low-alloy high-strength steel wire, including the following steps:

[0007] Fix the substrate;

[0008] The 3D model of the penetrating part is imported into the control system of the arc additive manufacturing equipment. The control system automatically performs slicing, layering, and scanning path planning on the penetrating part.

[0009] Set the process parameters for arc additive manufacturing;

[0010] Using filament, arc additive manufacturing is performed on a substrate according to process parameters and scanning path to obtain a through-hole component;

[0011] The through-hole component is machined and shaped.

[0012] Furthermore, in arc additive manufacturing, the wire feeding speed is controlled at 3.0–9.0 m / min, and the scanning speed is controlled at 0.20–0.35 m / min.

[0013] Furthermore, in arc additive manufacturing, the arc voltage is controlled at 21V to 27V, and the current is controlled at 180A to 280A, with the current changing synchronously with the wire feeding speed.

[0014] Furthermore, in arc additive manufacturing, the dry elongation of the filament is controlled to be 12~18mm.

[0015] Furthermore, arc additive manufacturing is performed using a cold metal transition-pulse mode.

[0016] Furthermore, the surface of the filament has a coating, the composition of which includes NiSO4, NiCl2, H3BO3 and TiO2.

[0017] Furthermore, in the coating, the ratio of NiSO4, NiCl2, H3BO3, and TiO2 is 7~8:3~5:2~4:1~3.

[0018] On the other hand, an embodiment of the present invention provides a through-hole component, which is prepared by the method described in the above embodiment; the through-hole component includes an integrally formed through-hole component body and flanges connected to both ends of the through-hole component body, the flanges being used to connect to a connecting plate or a pipe.

[0019] Furthermore, the yield strength of the penetrating component is ≥800MPa, the tensile strength is ≥850MPa, and the low-temperature impact absorption energy at -50℃ is ≥80J.

[0020] Compared with the prior art, the present invention can achieve at least one of the following beneficial effects:

[0021] 1. This invention uses electric arc additive manufacturing to produce through-hole components, which can integrally manufacture through-hole components with complex shapes. At the same time, a flange or skirt of a certain width is added at the connection position between the manufactured through-hole component and the connecting plate to connect with the connecting plate or pipe through the flange or skirt. Compared with traditional manufacturing methods, the manufactured through-hole component and the connecting plate or pipe can be connected by butt welding, thereby changing the fillet weld connection at the connection to a flat weld connection, which greatly reduces the welding manufacturing difficulty when connecting through-hole components, and can also reduce stress changes caused by asymmetry in fillet weld welding.

[0022] 2. This invention uses low-alloy high-strength steel wire for arc additive manufacturing. The wire has a low carbon content, which can significantly reduce the crack sensitivity of the prepared through-hole component. By adding Cr and Mo, dispersed carbide precipitation can be formed, thereby improving the strength and toughness of the through-hole component. At the same time, by adding a very small amount of alloying elements such as Ti and V, the carbide content of the through-hole component during the arc additive manufacturing process is increased, thereby refining the grains and further improving the strength and toughness of the through-hole component.

[0023] 3. The low-alloy high-strength steel wire of the present invention contains the alloying element Sn. SnO2 is formed at the local corrosion sites during the service of the penetrator, which inhibits the corrosion of the matrix. In the later corrosion process, the content of the dense α-FeOOH product is increased, which plays a good barrier role and improves the corrosion resistance of the penetrator. At the same time, a small amount of Cu element is also added to the wire. Cu element can be deposited on the surface of the penetrator to form a rust layer with protective properties, which improves the corrosion resistance of the penetrator.

[0024] 4. This invention uses coated wire for arc additive manufacturing, which greatly reduces molten pool spatter during the arc additive manufacturing process.

[0025] In this invention, the above-described technical solutions can be combined with each other to achieve more preferred combinations. Other features and advantages of this invention will be set forth in the following description, and some advantages may become apparent from the description or be learned by practicing the invention. The objects and other advantages of this invention can be realized and obtained through the details specifically pointed out in the description and drawings. Attached Figure Description

[0026] The accompanying drawings are for illustrative purposes only and are not intended to limit the invention. Throughout the drawings, the same reference numerals denote the same parts.

[0027] Figure 1 This is a schematic diagram of the structure of a through member according to some embodiments of the present invention.

[0028] Figure 2 A schematic diagram of welding a through-hole component and a connecting plate prepared by a conventional method.

[0029] Figure 3 This is a schematic diagram of the welding of a through member to a connecting plate or pipe according to some embodiments of the present invention.

[0030] Figure 4 This is a schematic diagram of the structural dimensions of the through-hole component in Embodiment 1 of the present invention.

[0031] Figure 5 This is a microstructure diagram of the penetrating component in Embodiment 1 of the present invention.

[0032] Figure 6 This is a surface morphology diagram of the rust layer on the penetrating component in Embodiment 1 of the present invention.

[0033] Figure 7 This is a local corrosion morphology diagram of the penetrating component in Embodiment 1 of the present invention.

[0034] Explanation of reference numerals in the attached figures:

[0035] 10. Penetrating component; 11. Penetrating component body; 12. Flange; 20. Connecting plate; 30. Connecting plate or pipe; 40. Fillet weld; 50. Flat weld. Detailed Implementation

[0036] Preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings, which form part of this application and are used together with the embodiments of the present invention to illustrate the principles of the present invention, but are not intended to limit the scope of the present invention.

[0037] Embodiments of the present invention provide a method for integrated arc additive manufacturing of a penetrating component, comprising: based on a three-dimensional model drawing of the penetrating component, performing arc additive manufacturing using low-alloy high-strength steel wire to obtain a penetrating component with structural dimensions consistent with the three-dimensional model drawing; such as Figure 1 As shown, the through-piece 10 includes an integrally formed through-piece body 11 and flanges 12 connected to both ends of the through-piece body 11.

[0038] This invention utilizes arc additive manufacturing to produce through-hole components, enabling the efficient and integrated fabrication of complex-shaped components. Simultaneously, a flange or skirt of a certain width is additively manufactured at the connection point between the through-hole component and the connecting plate, facilitating connection to the connecting plate or pipe. Compared to traditional manufacturing methods, the produced through-hole component and connecting plate can be connected via a butt joint, optimizing the fillet weld connection at the connecting plate into a flat weld connection. This significantly reduces welding difficulty and minimizes stress variations caused by asymmetrical fillet welds, resulting in high-quality welds.

[0039] Specifically, such as Figure 2As shown, when the through-piece is prepared using the traditional method, the obtained through-piece 10 is cylindrical. In order to connect it to the connecting plate or pipe, a flange 12 needs to be welded to one end of the through-piece 10 and a connecting plate 20 needs to be welded to the other end. All the welds are fillet welds 40. This welding method is difficult to process, has great difficulty in controlling the accuracy of the weld, and is prone to stress changes due to the asymmetry of the fillet weld.

[0040] like Figure 3 As shown, the through-hole component 10 is prepared by arc additive manufacturing according to the present invention, and flanges 12 of a certain width can be integrally additively manufactured at both ends of the cylindrical through-hole component body 11. When installing the through-hole component 10, the flanges 12 can be connected to the connecting plate or pipe 30. The flanges 12 and the connecting plate or pipe 30 can be butt welded, thereby optimizing the fillet weld 40 at the weld joint into a flat weld 50, which greatly reduces the welding difficulty and welding stress.

[0041] In some embodiments, the low-alloy high-strength steel wire used in arc additive manufacturing comprises, by mass percentage: C: 0.03–0.10%, Si: 0.4–0.8%, Mn: 1.50–2.20%, Ni: 2.7–3.5%, Cr: 0.50–0.80%, Mo: 0.50–1.00%, V: ≤0.001%, Ti: ≤0.05%, Sn: 0.01–0.03%, Cu: ≤0.015%, P: ≤0.008%, S: ≤0.008%, O: ≤0.005%, N: ≤0.005%, H: ≤0.001%, with Fe as the balance.

[0042] The low-alloy high-strength steel wire of this invention has a low C content, which can significantly reduce the crack sensitivity of the penetrating component. By adding appropriate amounts of Cr and Mo, dispersed carbide precipitation can be formed, thereby improving the strength and toughness of the penetrating component. At the same time, by adding a very small amount of alloying elements such as Ti and V, the carbide content of the penetrating component during the arc additive manufacturing process is increased, thereby refining the grains and further improving the strength and toughness of the penetrating component.

[0043] Specifically, carbon (C) is a strong solid solution strengthening element in wire materials, which can significantly improve the yield strength of high-strength steel. Excessive C content leads to a greater tendency for cracking during the arc-welded additive manufacturing process; a C content exceeding 0.2% results in excessively high strength, significantly reducing its low-temperature impact toughness; while insufficient C content is detrimental to the solid solution strengthening effect. Therefore, to ensure resistance to intense heat accumulation and reduce cracking tendency during the arc-welded wire additive manufacturing process of through-hole components, this invention designs the C content in the wire material to be 0.03~0.10%.

[0044] As an alloying element in steel, silicon (Si) typically constitutes a fraction of no less than 0.4% by mass. It significantly improves the steel's elastic limit, yield strength, and yield-to-tensile ratio. Simultaneously, Si enhances the hardenability of steel, resulting in a higher content of strengthened microstructure. However, in arc additive manufacturing, the heating and cooling rates of the molten pool are rapid. Excessive Si content can lead to a decrease in toughness. Therefore, the Si content should not be too high, ideally controlled between 0.4% and 0.8%.

[0045] The main functions of manganese (Mn) are deoxidation and desulfurization. In this invention, Mn, in combination with silicon (Si) for deoxidation, enhances the deoxidation and desulfurization effects, thereby reducing the size and content of inclusions in high-strength steel. Considering the adverse effects of Mn on the strength and plasticity of penetrating parts, the Mn content is controlled between 1.50% and 2.20%.

[0046] Ni is an austenite stabilizing element that promotes the formation of more martensite / bainite mixed microstructure in high-strength steel at room temperature, resulting in significant microstructural strengthening and improved toughness. However, when the Ni content exceeds 4%, it can easily lead to the formation of combined bainite microstructure in through-hole components, causing unstable toughness. Therefore, the Ni content is controlled between 2.5% and 3.5%.

[0047] Both Cr and Mo are ferrite-forming elements, which can lower the critical phase transformation temperature from austenite to ferrite, reduce the diffusion capacity of C, and improve the hardenability of weld metal. Furthermore, Cr can increase the steel's resistance to uniform corrosion. When Cr and Mo coexist, they can form dispersed carbide precipitation, thus significantly improving the strength and toughness of the steel. However, excessive Cr content can cause brittleness in through-hole components and reduce toughness.

[0048] Trace amounts of V and Ti can refine the grain size in steel and form carbides with C, resulting in precipitation strengthening. Ti can form fine, dispersed titanium carbide in steel, refining the martensite and bainite structures and providing precipitation strengthening. Under the heat accumulation of arc additive manufacturing, both V and Ti precipitate carbides in situ, forming fine, dispersed heterogeneous phases that provide nucleation sites for refining acicular ferrite and martensite structures, significantly improving the strength and toughness of through-hole components. However, excessive V and Ti content will lower the martensitic transformation temperature range, promote bainitic transformation, form granular bainite, and reduce the toughness of the steel. Therefore, the V content should be controlled to ≤0.001%, and the Ti content to ≤0.05%.

[0049] A small amount of Sn can combine with oxygen to form SnO2 during the service life of the penetrating component, inhibiting corrosion. In later stages of corrosion, it forms a composite corrosion product of SnO2, Fe, α-FeOOH, and graphite (SnO2-MG), creating a good barrier effect and significantly improving the long-term corrosion resistance of low-alloy high-strength steel. However, its content should not be too high, as excessive content will form large oxide particles at grain boundaries and within grains, reducing the mechanical properties and toughness of the penetrating component. Therefore, its content should be controlled between 0.01% and 0.03%.

[0050] Specifically, when the penetrating component contains a small amount of Sn, it will first form Sn(OH)2 in an acidic environment. This unstable phase transforms into Sn(OH)4, which then dehydrates to form SnO2. The entire corrosion cycle of the penetrating component can be divided into three stages: initial corrosion, intermediate corrosion, and late corrosion. The initial corrosion stage mainly focuses on the protective effect of the initial corrosion products on the easily corroded areas of the alloy steel. The late corrosion stage mainly focuses on the protective effect of the formed composite corrosion products on the steel substrate. In a corrosive environment, a large amount of H... + and C1 - On the substrate surface, the SnO2 phase accumulates at grain boundaries and high-energy grain boundaries. As the corrosion reaction proceeds, a stable SnO2-MG composite product phase forms on the substrate surface, inhibiting corrosion behavior and improving corrosion resistance. In the final corrosion stage, the SnO2-MG composite product becomes denser and more stable. The thickness of the composite product remains basically unchanged in the later stage of corrosion, and the corrosion resistance tends to stabilize and decreases.

[0051] Cu (Cu) can stabilize the austenite phase and can replace Ni in steel, reducing its content and significantly contributing to cost savings. Simultaneously, Cu can significantly improve the resistance of steel to uniform corrosion. Cu can deposit on the steel surface, thus inhibiting anodic dissolution; it can also form a protective rust layer (Cu₂O, CuO, CuCl) on the surface of low-carbon steel, improving the corrosion resistance of through-hole components. However, excessive Cu content can reduce the plasticity and toughness of steel, causing "hot brittleness," meaning cracking is likely to occur during high-temperature forging. Furthermore, controlling the Cu content in marine steel helps improve the radiation resistance of steel materials. Therefore, considering all factors, the Cu content should be controlled to ≤0.015%.

[0052] In some embodiments, the mass percentages of Cr and Mo in the high-strength steel wire satisfy Cr / Mo = 0.8~1.6. In this invention, appropriate Mo and Cr mass fractions affect the composition of carbides (M2C), thereby reducing the mismatch between carbides and the matrix, allowing the carbides to be more dispersed in the matrix, and thus improving the corrosion resistance and toughness of the penetrating component.

[0053] In some embodiments, the mass percentages of Cu and Sn in the high-strength steel wire satisfy Cu / Sn≥0.5. Cu and Sn have a synergistic effect, improving the corrosion resistance of the steel. Cu promotes the initiation of localized pitting corrosion but inhibits its propagation, while Sn promotes pitting growth but inhibits its initiation. When the mass fraction ratio of Cu / Sn is approximately Cu / Sn≥0.5, the corrosion rate of the steel can be significantly reduced.

[0054] Preferably, the high-strength steel wire comprises, by mass percentage: C: 0.05–0.07%, Si: 0.4–0.6%, Mn: 1.50–1.80%, Ni: 2.7–3.5%, Cr: 0.50–0.60%, Mo: 0.70–0.90%, V: 0.001%, Ti: 0.05%, Sn: 0.03%, Cu: ≤0.015%, P: ≤0.008%, S: ≤0.008%, O: ≤0.005%, N: ≤0.005%, H: ≤0.001%, with Fe as the balance.

[0055] In some embodiments, the diameter of the low-alloy high-strength steel wire is 1.2 mm or 1.6 mm.

[0056] In some embodiments, arc additive manufacturing using low-alloy high-strength steel wire is performed based on a three-dimensional model of the through-hole, including the following steps:

[0057] (1) Fix the substrate to ensure that it does not loosen;

[0058] (2) Import the three-dimensional model of the penetrating part into the control system of the arc additive manufacturing equipment. The control system automatically performs slicing and layering and scanning path planning for the penetrating part.

[0059] (3) Set the process parameters for arc additive manufacturing;

[0060] (4) Using the above-mentioned wire material, and following the above-mentioned process parameters and the planned scanning path, arc additive manufacturing is performed on the substrate to obtain a through-hole component;

[0061] (5) Machining the through-parts to make them meet the requirements for further welding, so that the through-parts can be connected to the connecting plate or pipe by welding.

[0062] During additive manufacturing, the forming condition of the shaped component surface can be monitored in real time. If poor forming occurs, the process parameters can be adjusted in a timely manner based on experience to improve the surface quality of the shaped component.

[0063] In some embodiments, arc additive manufacturing equipment, such as the Fonnis CMT welding machine, can be used for arc additive manufacturing. The substrate material used in arc additive manufacturing is 800MPa grade low-alloy high-strength steel, and the plate thickness can be 15~30mm. When fixing the substrate, it can be fixed on the eight-axis linkage base of the arc additive manufacturing equipment to ensure that it does not become loose.

[0064] In some embodiments, employing a cold metal transition-pulse mode for arc additive manufacturing can minimize heat input, reduce heat accumulation during the additive manufacturing process, and prevent the grain size of the through-part from becoming coarser due to severe heat accumulation.

[0065] In some embodiments, the protective gas in arc additive manufacturing is Ar + 5% CO2 or 100% Ar.

[0066] In some embodiments, in arc additive manufacturing, the wire feed speed is controlled to be 3.0–9.0 m / min, and the scanning speed is 0.20–0.35 m / min. A faster scanning speed results in a finer microstructure and higher strength in the through-hole, but poorer toughness; a higher wire feed speed results in a larger melt flow rate and a higher current, leading to a coarser microstructure in the through-hole, which is detrimental to both strength and toughness. For example, the wire feed speeds are 3.0 m / min, 4.0 m / min, 5.0 m / min, 6.0 m / min, 7.0 m / min, 8.0 m / min, and 9.0 m / min; and the scanning speeds are 0.20 m / min, 0.25 m / min, 0.30 m / min, and 0.35 m / min.

[0067] In some embodiments, in arc additive manufacturing, the arc voltage is controlled to be 21V–27V, the current to be 180A–280A, and the arc voltage correction is 0. The arc additive manufacturing process employs unified control, meaning the current and wire feed speed change synchronously.

[0068] In some embodiments, in arc additive manufacturing, the wire elongation is controlled to be 12-18 mm, for example, 12 mm, 13 mm, 14 mm, 15 mm, 16 mm, 17 mm, or 18 mm. Preferably, the elongation is 15 mm. In arc additive manufacturing, a suitable elongation can ensure the stability of the arc, thereby improving the forming quality. Excessive elongation can easily lead to increased molten pool spatter, reducing material utilization and causing molten pool instability; insufficient elongation may result in arc instability, affecting the forming quality.

[0069] This invention optimizes the process parameters in arc additive manufacturing within the above-mentioned range, enabling the production of penetrating parts with uniform and fine microstructure, high strength, and high toughness.

[0070] In some embodiments, the surface of the filament used in arc additive manufacturing has a coating comprising NiSO4, NiCl2, H3BO3, and TiO2. The coating on the filament surface of the present invention, containing the above-mentioned components, improves the process adaptability of the filament and significantly reduces molten pool spatter during arc additive manufacturing.

[0071] Preferably, the ratio of NiSO4, NiCl2, H3BO3, and TiO2 in the coating on the wire surface is 7~8:3~5:2~4:1~3. NiSO4 and NiCl2 primarily help eliminate oil contamination in the molten pool during arc additive manufacturing and improve the wettability of the molten pool. H3BO3 and TiO2 mainly improve the stability and smoothness of the welding wire during feeding, thereby reducing molten pool spatter.

[0072] In some embodiments, the low-alloy high-strength steel wire used in arc additive manufacturing can be obtained by the following preparation method:

[0073] S1, Vacuum induction melting of raw materials to obtain molten steel;

[0074] S2, the molten steel is poured into electrode rods;

[0075] S3, vacuum consumable arc melting of electrode rods, followed by casting to obtain rod ingots;

[0076] S4, forging the bar ingot, rolling the forged bar ingot in multiple passes to prepare wire rod;

[0077] S5, the wire rod is annealed and then water-cooled;

[0078] S6, the wire rod is drawn to produce wire.

[0079] This invention employs a "dual vacuum" melting method in the preparation of high-strength steel wire, namely vacuum induction melting and vacuum consumable electric arc furnace melting, to maximize the high-purity smelting of high-strength steel and the quality of the wire. Compared with electroslag remelting, the method of this invention has higher precision in controlling oxygen, nitrogen, and sulfur elements, and can better reduce the content and size of inclusions such as oxides and sulfides, thereby improving the toughness of the penetrating component.

[0080] In step S1, a vacuum induction furnace can be used to perform initial melting of the raw materials to obtain molten steel. To ensure that the content of impurity elements in the molten steel is low, the vacuum level is controlled to be ≤10Pa during vacuum induction melting.

[0081] In step S2, vacuum casting is used when pouring molten steel to prevent oxygenation and ensure that the oxygen content in the cast electrode rod is low.

[0082] In some embodiments, the tapping temperature of the molten steel is 1640~1650℃ during casting to ensure the smoothness of the casting process. Too high or too low a tapping temperature is not conducive to the smoothness of casting.

[0083] In step S3, after machining the electrode rod to remove the oxide scale, it is then subjected to vacuum arc melting to avoid introducing impurities into the rod. This invention further deoxidizes and denitrifies the electrode rod through vacuum arc melting, resulting in highly clean rod ingots. It can control the oxygen and nitrogen content in the wire to below 0.005% and the sulfur content to below 0.008%, further reducing the content and size of inclusions such as oxides and sulfides, thereby improving the toughness of the through-hole component.

[0084] In some embodiments, the electrode rod can be fed into a vacuum arc furnace for secondary vacuum melting. During melting, the voltage can be adjusted to 30~40V and the current to 2~6kA to ensure that the melting furnace has a suitable temperature, so that the molten steel has good fluidity, enhances the stirring effect of the molten pool, helps to remove impurities and gases in the molten pool, and improves the purity of the ingot.

[0085] In step S4, the bar ingot is first heated and held at 1050~1200℃ for 2~3 hours to homogenize the ingot and ensure the uniformity of the internal structure of the material, which facilitates subsequent forging. Then, the bar ingot is forged, and the final forging temperature is controlled to be ≥950℃. After forging, it is air-cooled. For example, the bar ingot can be forged into a bar with a diameter of 50mm.

[0086] In some embodiments, the forged bar stock can be rolled in multiple passes at 850~1050°C to obtain wire rod. For example, it can be rolled into wire rod with a diameter of 8 mm.

[0087] In step S5, when annealing the wire rod, the annealing temperature is 1100~1200℃ and the annealing time is 1~2h. Holding at this temperature can further ensure the uniformity of the internal structure of the wire rod.

[0088] In step S6, the wire rod is first pickled to remove surface oxide scale. After washing and drying, it undergoes a coating treatment. This coating treatment forms a phosphate-based thin film on the surface of the wire rod. This porous film allows for better lubrication, resulting in an effective lubricating film during drawing, reducing friction, wear, and cracking, and improving wear resistance. After the coating treatment, the wire rod is dried at a temperature of 100-150°C.

[0089] The coated wire rod is drawn, and online annealing is performed during the drawing process at a temperature of 1100~1200℃. Online annealing reduces the hardness and strength of the wire rod, making it easier to draw. After multiple drawing passes, the wire rod can be produced into wires with a diameter of 1.2mm or 1.6mm.

[0090] In some embodiments, the preparation method further includes step S7, which involves coating the prepared wire with a coating comprising NiSO4, NiCl2, H3BO3, and TiO2. This invention improves the process adaptability of the wire by coating it with a coating containing the aforementioned components, and significantly reduces molten pool spatter during arc additive manufacturing.

[0091] Embodiments of the present invention also provide a penetrating member for conveying liquid or gaseous media in a ship. The penetrating member is prepared using the method described in the above embodiments. Figure 1 As shown, the through-piece 10 includes an integrally formed through-piece body 11 and flanges 12 connected to both ends of the through-piece body 11. The flanges 12 are used to connect to a connecting plate or a pipe.

[0092] In embodiments of the present invention, the through-hole component obtained by arc additive manufacturing using the above-mentioned wire has a yield strength ≥800MPa, a tensile strength ≥850MPa, and a low-temperature impact absorption energy of -50℃ ≥50J.

[0093] The following examples further illustrate the arc additive manufacturing method for the penetrating component of the present invention.

[0094] Example 1

[0095] The method for manufacturing a penetrating component by electric arc additive manufacturing in this embodiment includes:

[0096] (1) Fix a 600×600×30mm low alloy high strength steel plate (plate thickness 30mm) on the eight-axis linkage base of the arc additive manufacturing equipment (the equipment is a Funnis Advance welding machine) to ensure that it does not loosen.

[0097] (2) As Figure 4 The through-part graphic shown (the dimensions of each part in the figure are in mm) is imported into the control system of the arc additive manufacturing equipment to automatically complete the slicing, layering, and path planning.

[0098] (3) Set the process parameters for arc additive manufacturing: adopt cold metal transfer (CMT) + pulse (P) mode, current is 240A, arc voltage is 25V, scanning speed is 0.35m / min, wire feed speed is 7.0m / min, dry extension is 15mm, arc voltage correction is 0, and protective gas is Ar + 5% CO2.

[0099] (4) Additive manufacturing begins with low-alloy high-strength steel wire. The low-alloy high-strength steel wire comprises, by mass percentage: C: 0.05%, Si: 0.5%, Mn: 1.80%, Ni: 3.0%, Cr: 0.63%, Mo: 0.6%, V: 0.001%, Ti: 0.03%, Sn: 0.02%, Cu: 0.015%, P: ≤0.008%, S: ≤0.008%, O: ≤0.005%, N: ≤0.005%, H: ≤0.001%, with Fe as the balance. The coating composition on the surface of the wire includes NiSO4, NiCl2, H3BO3, and TiO2 in a ratio of 8:4:3:2.

[0100] (5) After the additive manufacturing is completed, the obtained through part is shaped by machining to meet the requirements of further welding.

[0101] Samples were taken from the obtained penetrating section along the direction parallel to the scanning path to prepare tensile specimens and low-temperature impact toughness specimens.

[0102] like Figure 5 As shown in the microstructure diagram of the penetrating component, dispersed vanadium carbide, titanium carbide and other carbides can be observed, which is beneficial for refining grains and improving the strength and toughness of the penetrating component.

[0103] After a period of service, a rust layer forms on the surface of the penetrating component, such as... Figure 6 As shown. Scanning electron microscopy was used to irradiate localized rust layers on the surface of the penetrating component to obtain the localized corrosion morphology, as shown. Figure 7 As shown, a large number of dense SnO2-MG composite products exist in the corrosion area on the surface of the penetrating part, which inhibits further corrosion behavior of the penetrating part.

[0104] Example 2

[0105] The method for manufacturing a penetrating component by electric arc additive manufacturing in this embodiment includes:

[0106] (1) Fix a 600×600×30mm low alloy high strength steel plate (plate thickness 30mm) on the eight-axis linkage base of the arc additive manufacturing equipment (the equipment is a Funnis Advance welding machine) to ensure that it does not loosen.

[0107] (2) As Figure 4 The through-piece graphic shown is imported into the control system of the arc additive manufacturing equipment, which automatically completes slicing, layering, and path planning.

[0108] (3) Set the process parameters for arc additive manufacturing: adopt cold metal transfer (CMT) + pulse (P) mode, current is 220A, arc voltage is 24V, scanning speed is 0.30m / min, wire feed speed is 6.0m / min, dry extension is 16mm, arc voltage correction is 0, and protective gas is Ar + 5% CO2.

[0109] (4) Additive manufacturing begins with low-alloy high-strength steel wire. The low-alloy high-strength steel wire comprises, by mass percentage: C: 0.10%, Si: 0.6%, Mn: 2.00%, Ni: 3.5%, Cr: 0.80%, Mo: 0.90%, V: 0.001%, Ti: 0.05%, Sn: 0.02%, Cu: 0.015%, P: ≤0.008%, S: ≤0.008%, O: ≤0.005%, N: ≤0.005%, H: ≤0.001%, with Fe as the balance. The coating composition on the surface of the wire includes NiSO4, NiCl2, H3BO3, and TiO2 in a ratio of 7:5:2:1.

[0110] (5) After the additive manufacturing is completed, the obtained through part is shaped by machining to meet the requirements of further welding.

[0111] Example 3

[0112] The method for manufacturing a penetrating component by electric arc additive manufacturing in this embodiment includes:

[0113] (1) Fix a 600×600×30mm low alloy high strength steel plate (plate thickness 30mm) on the eight-axis linkage base of the arc additive manufacturing equipment (the equipment is a Funnis Advance welding machine) to ensure that it does not loosen.

[0114] (2) As Figure 4 The through-piece graphic shown is imported into the control system of the arc additive manufacturing equipment, which automatically completes slicing, layering, and path planning.

[0115] (3) Set the process parameters for arc additive manufacturing: adopt cold metal transfer (CMT) + pulse (P) mode, current is 200A, arc voltage is 23V, scanning speed is 0.30m / min, wire feed speed is 5.0m / min, dry extension is 14mm, arc voltage correction is 0, and protective gas is 100%Ar.

[0116] (4) Additive manufacturing begins with low-alloy high-strength steel wire. The low-alloy high-strength steel wire comprises, by mass percentage: C: 0.03%, Si: 0.4%, Mn: 2.20%, Ni: 2.70%, Cr: 0.50%, Mo: 0.50%, V: 0.001%, Ti: 0.04%, Sn: 0.03%, Cu: 0.015%, P: ≤0.008%, S: ≤0.008%, O: ≤0.005%, N: ≤0.005%, H: ≤0.001%, with Fe as the balance. The wire surface has no coating.

[0117] (5) After the additive manufacturing is completed, the obtained through part is shaped by machining to meet the requirements of further welding.

[0118] Example 4

[0119] The difference between this embodiment and Embodiment 1 is that the scanning speed is 0.20 m / min, the wire feeding speed is 3.0 m / min, the current is 180 A, and the arc voltage is 21 V in the arc additive manufacturing.

[0120] Example 5

[0121] The difference between this embodiment and Embodiment 1 is that the scanning speed is 0.35 m / min, the wire feeding speed is 9.0 m / min, the current is 280 A, and the arc voltage is 27 V in the arc additive manufacturing.

[0122] Example 6

[0123] The difference between this embodiment and Embodiment 1 is that the 800MPa grade high-strength steel wire for arc additive manufacturing comprises, by mass percentage: C: 0.06%, Si: 0.5%, Mn: 1.70%, Ni: 3.3%, Cr: 0.6%, Mo: 0.7%, V: 0.001%, Ti: 0.05%, Sn: 0.03%, Cu: 0.015%, P: ≤0.008%, S: ≤0.008%, O: ≤0.005%, N: ≤0.005%, H: ≤0.001%, with Fe as the balance.

[0124] Comparative Example 1

[0125] The difference from Example 1 is that in the arc additive manufacturing process of this comparative example, the scanning speed is 0.5 m / min, the wire feeding speed is 9.5 m / min, the current is 285 A, and the arc voltage is 27 V.

[0126] Comparative Example 2

[0127] The difference from Example 1 is that in the arc additive manufacturing process of this comparative example, the scanning speed is 0.15 m / min, the wire feeding speed is 2.5 m / min, the current is 170 A, and the arc voltage is 20 V.

[0128] Comparative Example 3

[0129] The difference from Example 1 is that the dry extension is 20 mm in the arc additive manufacturing process of this comparative example.

[0130] Comparative Example 4

[0131] The difference from Example 1 is that the dry extension is 10 mm in the arc additive manufacturing process of this comparative example.

[0132] Comparative Example 5

[0133] The difference from Example 1 is that the filament used in this comparative example does not contain Sn.

[0134] Comparative Example 6

[0135] The difference from Example 1 is that the wire used in this comparative example does not contain Cu.

[0136] Comparative Example 7

[0137] The difference from Example 1 is that the Sn content in the filament of this comparative example is excessive, at 0.04%.

[0138] Comparative Example 8

[0139] The difference from Example 1 is that the Cu content in the filament of this comparative example is excessive, at 0.02%.

[0140] Comparative Example 9

[0141] The difference from Example 1 is that the filament used in this comparative example does not contain V.

[0142] Comparative Example 10

[0143] The difference from Example 1 is that the filament used in this comparative example does not contain Ti.

[0144] Comparative Example 11

[0145] The difference from Example 1 is that the V content in the comparative example filament is excessive, at 0.002%.

[0146] Comparative Example 12

[0147] The difference from Example 1 is that the Ti content in the filament of this comparative example is excessive, at 0.06%.

[0148] The composition of the low-alloy high-strength steel wire used in each embodiment and comparative example is shown in Table 1. The process parameters for arc additive manufacturing in each embodiment and comparative example are shown in Table 2.

[0149] Table 1. Fiber composition (wt.%) of each embodiment and comparative example

[0150]

[0151] Table 2. Process parameters of the arc additive manufacturing apparatus in each embodiment and comparative examples 1-4

[0152]

[0153] For each embodiment and comparative example, tensile and toughness specimens were selected along the direction parallel to the scanning path for the through-hole component, and tensile and low-temperature impact toughness tests were conducted. The test results are shown in Table 3.

[0154] As shown in Table 3, the process parameters in the electric arc additive manufacturing process in Examples 1 to 6 were set within a suitable range, and the elements of the wire used were also within a suitable range, so that the prepared penetrating parts had excellent mechanical properties and corrosion resistance, with a yield strength of over 800 MPa, a tensile strength of over 859 MPa, a low-temperature impact absorption energy of over 80KV2 at -50℃, and an annual average corrosion rate of less than 0.45mm / a.

[0155] The scanning speed and wire feeding speed in Comparative Examples 1 and 2 were not within the appropriate process range, resulting in defects in the forming process of arc additive manufacturing, and the strength and toughness of the through parts deteriorated.

[0156] In Comparative Examples 3 and 4, the excessive or insufficient elongation of the molten pool during the arc additive manufacturing process caused instability in the molten pool and voltage fluctuations. As a result, the strength and toughness of the final through-hole component were reduced compared to Example 1.

[0157] Comparative Examples 5 and 6, lacking Sn or Cu elements, exhibited relatively poor corrosion resistance. Comparative Examples 7 and 8, with excessively high Sn or Cu content, resulted in reduced low-temperature impact absorption energy, i.e., decreased toughness. Comparative Examples 9 and 10, lacking V or Ti, resulted in reduced dispersed carbides in the penetrating parts, leading to decreased yield strength and low-temperature impact absorption energy. Comparative Examples 11 and 12, with excessively high V or Ti content, while showing improved yield strength and tensile strength compared to Example 1, exhibited decreased impact toughness.

[0158] Table 3 Mechanical properties and corrosion resistance of the penetration components in each embodiment

[0159]

[0160] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for integrated electric arc additive manufacturing of a through-hole component, characterized in that, include: Based on the three-dimensional model of the penetrating component, low-alloy high-strength steel wire is used for arc additive manufacturing to obtain a penetrating component with the same structural dimensions as the three-dimensional model. The through-hole component includes an integrally formed through-hole component body and flanges connected to both ends of the through-hole component body; The low-alloy high-strength steel wire comprises, by mass percentage: C: 0.03–0.10%, Si: 0.4–0.8%, Mn: 1.50–2.20%, Ni: 2.7–3.5%, Cr: 0.50–0.80%, Mo: 0.50–1.00%, V: ≤0.001%, Ti: ≤0.05%, Sn: 0.01–0.03%, Cu: ≤0.015%, P: ≤0.008%, S: ≤0.008%, O: ≤0.005%, N: ≤0.005%, H: ≤0.001%, with Fe as the balance.

2. The method according to claim 1, characterized in that, The process of arc additive manufacturing using low-alloy high-strength steel wire based on the three-dimensional model of the through-hole component includes the following steps: Fix the substrate; The three-dimensional model of the penetrating component is imported into the control system of the arc additive manufacturing equipment, and the control system automatically performs slicing, layering and scanning path planning on the penetrating component. Set the process parameters for the electric arc additive manufacturing; Using the aforementioned filament, and following the aforementioned process parameters and scanning path, arc additive manufacturing is performed on the substrate to obtain the through-hole component; The through-hole component is machined and shaped.

3. The method according to claim 2, characterized in that, In the aforementioned electric arc additive manufacturing, the wire feeding speed is controlled to be 3.0–9.0 m / min, and the scanning speed is controlled to be 0.20–0.35 m / min.

4. The method according to claim 3, characterized in that, In the electric arc additive manufacturing process, the arc voltage is controlled to be 21V to 27V and the current is 180A to 280A, and the current changes synchronously with the wire feeding speed.

5. The method according to claim 2, characterized in that, In the electric arc additive manufacturing process, the dry elongation of the filament is controlled to be 12~18mm.

6. The method according to claim 1, characterized in that, Arc additive manufacturing is performed using a cold metal transition-pulse mode.

7. The method according to any one of claims 1-6, characterized in that, The surface of the filament has a coating, the composition of which includes NiSO4, NiCl2, H3BO3 and TiO2.

8. The method according to claim 7, characterized in that, In the coating, the ratio of NiSO4, NiCl2, H3BO3, and TiO2 is 7~8:3~5:2~4:1~3.

9. A penetrating member, characterized in that, The through-piece is prepared by the method according to any one of claims 1-8; the through-piece includes an integrally formed through-piece body and flanges connected to both ends of the through-piece body, the flanges being used to connect to a connecting plate or a pipe.

10. The penetrating member according to claim 9, characterized in that, The through-hole component has a yield strength ≥800MPa, a tensile strength ≥850MPa, and an impact absorption energy of -50℃ ≥80J.

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