Method for preparing beryllium-aluminum composite material by using beryllium waste material as raw material through electric arc additive manufacturing

Abstract

The invention relates to a method for preparing a beryllium-aluminum composite material, in particular to a method for preparing a beryllium-aluminum composite material by taking a beryllium waste material as a raw material through electric arc additive manufacturing. The problems that existing waste beryllium resources are difficult to recycle, and beryllium oxide in beryllium waste reduces the beryllium-aluminum interface bonding strength are solved. According to the method, beryllium oxide is removed through variable-polarity alternating-current arcs, interface beryllium oxide is removed through synergistic cathode atomization and electron cloud reduction of variable-polarity currents, the cathode atomization effect at the negative polarity stage preferentially acts on an oxide layer, and high-energy electron currents impact and crush the surface beryllium oxide through kinetic energy; under the action of an alternating electric field, high-density electron cloud of the arc plasma decomposes residual beryllium oxide through a reduction reaction, finally clean metallurgical bonding of the beryllium-aluminum interface is achieved, and the interface bonding strength of the beryllium-aluminum composite material is improved. The beryllium-aluminum composite material welding wire prepared by using the waste beryllium as the raw material reduces the dependence on beryllium primary mineral resources. And the preparation period is short, near-net forming is achieved, and the material utilization rate is increased.

Description

Technical Field

[0001] This invention relates to a method for preparing beryllium-aluminum composite materials. Background Technology

[0002] Beryllium resources are limited and difficult to mine. Using beryllium-aluminum composites is more resource-efficient than using metallic beryllium, meeting the application needs of national defense, military, and aerospace, and can replace metallic beryllium in most fields. Currently, the price of beryllium-aluminum composites remains high. From a raw material perspective, beryllium powder, as a rare metal resource, has limited reserves and is difficult to mine, directly leading to its high price. Against this backdrop, beryllium waste, as a potential resource, has received increasing attention.

[0003] These beryllium wastes originate from various production processes, such as processing scraps, discarded parts, and chips. However, because beryllium is a reactive metal, it generates a large amount of beryllium oxide during processing, making it difficult to recycle. From a materials performance perspective, the inherent beryllium oxide layer on the surface of beryllium powder significantly degrades interfacial bonding performance. Calculation results show that the adhesion work of the BeO-Al interface (0.09 J / m²) is only 5% of that of a clean Be-Al interface (1.78 J / m²). Furthermore, the presence of interfacial beryllium oxide reduces the interfacial bonding strength between beryllium and aluminum in beryllium / aluminum composites, directly causing premature fracture of the composite under tensile loads due to interfacial debonding. However, existing processes cannot effectively eliminate the negative impact of interfacial beryllium oxide. Therefore, a method for recycling waste beryllium to prepare high-performance beryllium-aluminum composites is urgently needed. Summary of the Invention

[0004] To address the difficulties in recycling existing waste beryllium resources and the problem that beryllium oxide in beryllium waste reduces the interfacial bonding strength between beryllium and aluminum, this invention proposes a method for preparing beryllium-aluminum composite materials using beryllium waste as raw material and employing arc additive manufacturing.

[0005] The present invention describes a method for preparing beryllium-aluminum composite materials using beryllium waste as raw material via arc additive manufacturing, which is carried out according to the following steps:

[0006] 1. Select beryllium-aluminum composite welding wire and perform surface deoxidation and cleaning;

[0007] The beryllium-aluminum composite welding wire is made of an aluminum matrix and beryllium particle reinforcement.

[0008] The beryllium particle reinforcement is beryllium waste;

[0009] The volume fraction of beryllium particle reinforcement in the beryllium-aluminum composite welding wire is 30%-70%.

[0010] 2. Clean the substrate before deposition and then preheat the substrate;

[0011] The method for cleaning the substrate is as follows: first, remove oxides and oil stains from the substrate surface, and then clean the substrate surface with anhydrous ethanol or acetone.

[0012] The substrate is preheated at a temperature of 200-300℃;

[0013] 3. Beryllium aluminum composite material was prepared by layer-by-layer deposition using arc additive manufacturing in an inert gas atmosphere. A variable polarity AC waveform power supply was selected. After each layer was deposited, the beryllium aluminum composite material was allowed to cool down to 80-150℃ before the next layer was deposited.

[0014] The process parameters for arc additive manufacturing are as follows: wire extension: 10-15mm, wire feed speed: 2-8m / min, welding torch movement speed: 0.2-0.8m / min; the positive polarity ratio of the variable polarity AC waveform is 40-80%, the peak current of the AC waveform is 100-150A, the voltage is 18-25V, and the polarity change frequency of the variable polarity AC waveform is 50-200Hz. The welding torch movement speed is matched with the welding wire diameter and current to ensure stable droplet transfer.

[0015] The present invention has the following beneficial effects:

[0016] 1. This invention employs a variable polarity alternating current arc to remove beryllium oxide. The variable polarity current removes the interfacial beryllium oxide through synergistic cathode atomization and electron cloud reduction: During one cycle of the variable polarity alternating current arc, when the beryllium or beryllium-aluminum interface is connected to the negative electrode of the power supply (the negative polarity stage), a large number of positively charged gas ions (mainly argon ions Ar) are released. + Under the acceleration of the electric field, the beryllium or beryllium-aluminum interface is bombarded with extremely high kinetic energy to produce a cathode atomization effect, which preferentially acts on the oxide layer. The high-energy electron flow breaks the surface beryllium oxide through kinetic energy impact. Under the action of the alternating electric field, the high-density electron cloud of the arc plasma decomposes the residual beryllium oxide through reduction reaction, and finally achieves clean metallurgical bonding of the beryllium-aluminum interface, improving the interfacial bonding strength of the beryllium-aluminum composite material.

[0017] 2. This invention uses beryllium-aluminum composite welding wire prepared from waste beryllium as raw material and performs arc additive manufacturing, which effectively reduces the dependence on primary beryllium mineral resources.

[0018] 3. This invention utilizes the rapid solidification characteristics of additive manufacturing to refine the grain structure of beryllium aluminum composite materials, thereby simultaneously improving strength and plasticity.

[0019] 4. This invention has low requirements for the size and morphology of beryllium and does not require the beryllium waste to have high sphericity and good flowability.

[0020] 5. Compared with the traditional beryllium aluminum composite material preparation process, the present invention can prepare components of different shapes without molds, with a short preparation cycle, and can achieve near-net-shape forming of components, greatly improving material utilization and significantly reducing the price of beryllium aluminum components. Attached Figure Description

[0021] Figure 1 This is a photograph of the transmission structure of the beryllium aluminum composite material prepared in Example 1. Detailed Implementation

[0022] The technical solution of the present invention is not limited to the specific embodiments listed below, but also includes any reasonable combination of the specific embodiments.

[0023] Specific Implementation Method 1: This implementation method for preparing beryllium-aluminum composite materials using beryllium waste as raw material via arc additive manufacturing is carried out according to the following steps:

[0024] 1. Select beryllium-aluminum composite welding wire and perform surface deoxidation and cleaning;

[0025] The beryllium-aluminum composite welding wire is made of an aluminum matrix and beryllium particle reinforcement.

[0026] The beryllium particle reinforcement is beryllium waste;

[0027] The volume fraction of beryllium particle reinforcement in the beryllium-aluminum composite welding wire is 30%-70%.

[0028] 2. Clean the substrate before deposition and then preheat the substrate;

[0029] The method for cleaning the substrate is as follows: first, remove oxides and oil stains from the substrate surface, and then clean the substrate surface with anhydrous ethanol or acetone.

[0030] The substrate is preheated at a temperature of 200-300℃;

[0031] 3. Beryllium aluminum composite material was prepared by layer-by-layer deposition using arc additive manufacturing in an inert gas atmosphere. A variable polarity AC waveform power supply was selected. After each layer was deposited, the beryllium aluminum composite material was allowed to cool down to 80-150℃ before the next layer was deposited.

[0032] The process parameters for arc additive manufacturing are as follows: wire extension: 10-15mm, wire feed speed: 2-8m / min, welding torch movement speed: 0.2-0.8m / min; the positive polarity ratio of the variable polarity AC waveform is 40-80%, the peak current of the AC waveform is 100-150A, the voltage is 18-25V, and the polarity change frequency of the variable polarity AC waveform is 50-200Hz. The welding torch movement speed is matched with the welding wire diameter and current to ensure stable droplet transfer.

[0033] 1. This embodiment uses a variable polarity alternating current arc to remove beryllium oxide. The variable polarity current removes the interfacial beryllium oxide through synergistic cathode atomization and electron cloud reduction: During one cycle of the variable polarity alternating current arc, when the beryllium or beryllium-aluminum interface is connected to the negative electrode of the power supply in the negative polarity phase, a large number of positively charged gas ions (mainly argon ions Ar) are generated. + Under the acceleration of the electric field, the beryllium or beryllium-aluminum interface is bombarded with extremely high kinetic energy to produce a cathode atomization effect, which preferentially acts on the oxide layer. The high-energy electron flow breaks the surface beryllium oxide through kinetic energy impact. Under the action of the alternating electric field, the high-density electron cloud of the arc plasma decomposes the residual beryllium oxide through reduction reaction, and finally achieves clean metallurgical bonding of the beryllium-aluminum interface, improving the interfacial bonding strength of the beryllium-aluminum composite material.

[0034] 2. This embodiment uses beryllium-aluminum composite welding wire prepared from waste beryllium as raw material and performs arc additive manufacturing, which effectively reduces the dependence on primary beryllium mineral resources.

[0035] 3. This embodiment utilizes the rapid solidification characteristics of additive manufacturing to refine the grain structure of beryllium aluminum composite materials and simultaneously improve their strength and plasticity.

[0036] 4. This embodiment has low requirements for the size and morphology of beryllium, and does not require the beryllium waste to have high sphericity and good flowability.

[0037] 5. Compared with the traditional beryllium aluminum composite material preparation process, this embodiment can prepare components of different shapes without molds, with a short preparation cycle, and can achieve near-net-shape forming of components, greatly improving material utilization and significantly reducing the price of beryllium aluminum components.

[0038] Specific Implementation Method Two: This implementation method differs from Specific Implementation Method One in that the preparation method of the beryllium aluminum composite welding wire in step one is as follows:

[0039] Step (1): Preparation of beryllium / aluminum composite material

[0040] Beryllium / aluminum composites were prepared using a self-venting pressure infiltration method.

[0041] ① After the beryllium particle reinforcement and aluminum matrix are mixed evenly, they are loaded into a steel mold and pressed into a preform. The pressing pressure is 80-110kN and the holding time is 2-4min. Then the steel mold containing the preform is placed in a preheating furnace and preheated at 510-560℃ for 2h.

[0042] ② Melt the aluminum substrate at a temperature of 820-860℃ to obtain liquid aluminum, and then pour the liquid aluminum into the steel mold that was preheated in step ①;

[0043] ③ Apply a pressure of 20-35MPa to the pressure head and move it downward at a speed of 5mm / min. Hold the pressure at 20-35MPa for 3-4 minutes, and then cool it with circulating water to obtain a beryllium / aluminum composite material.

[0044] Step (2): Preheating of beryllium / aluminum composite material and hot extrusion die

[0045] First, preheat the beryllium / aluminum composite material to a temperature of 400℃-600℃, and then hold it at a temperature of 400℃-600℃ for 0.5h-6h; the hot extrusion die is held at a temperature 10℃-50℃ lower than the preheating temperature of the beryllium / aluminum composite material for 0.5h-6h.

[0046] Step (3): Hot extrusion preparation of beryllium / aluminum composite rods

[0047] The preheated beryllium / aluminum composite material is loaded into a hot extrusion die and hot extruded using a press at a rate of 30-120 mm / min to obtain multiple beryllium / aluminum composite material rods in one operation.

[0048] In the extrusion die, the extrusion nozzle is a multi-hole extrusion nozzle with a hole diameter of 3mm-10mm and a number of holes of 2-10; the diameter of the preheated beryllium / aluminum composite material is 34-36mm;

[0049] Step (4): Annealing treatment of beryllium / aluminum composite rods

[0050] The beryllium / aluminum composite rods obtained in step three are heated to 200-600℃ and then kept at 200-600℃ for 0.5-6 hours.

[0051] Step (5): Hot spinning forging to prepare beryllium / aluminum composite filaments

[0052] Beryllium / aluminum composite bars are subjected to multi-pass rotary forging using a rotary forging machine. The multi-pass rotary forging process is as follows: the rotary forging temperature is 200-600℃, the deformation per pass is 1%-10%, the feed rate is 10-200mm / min, the rotary forging frequency is 10-100Hz, and annealing is performed after each rotary forging pass at the same temperature as the rotary forging temperature for 19-21min.

[0053] Specific Implementation Method 3: This implementation method differs from Specific Implementation Method 1 or 2 in that the cleaning in step 1 uses anhydrous ethanol.

[0054] Specific Implementation Method Four: This implementation method differs from one of the specific implementation methods one to three in that the particle size of the beryllium particle reinforcement in the beryllium aluminum composite welding wire described in step one is 10μm-800μm.

[0055] Specific Implementation Method Five: This implementation method differs from one of the specific implementation methods one to four in that the composition of the aluminum matrix in step one is: Mg 0.01-0.05wt%, Si 0.01-0.25%, Fe 0.01-0.4%, Mn 0.01-0.02%, Cu 0.01-0.04%, O 0.05-0.5%, with the balance being Al.

[0056] Specific Implementation Method Six: This implementation method differs from one of the specific implementation methods one to five in that the diameter of the beryllium aluminum composite welding wire in step one is 1-1.6mm.

[0057] Specific Implementation Method Seven: This implementation method differs from Specific Implementation Methods One to Six in that the composition of the beryllium waste in Step One is: O 0.01-8%, Fe 0.03-2%, Al 0.01-0.5%, Mn 0.01-0.5%, Si 0.01-0.2%, with the balance being Be.

[0058] Specific Implementation Method Eight: This implementation method differs from one of the specific implementation methods one to seven in that the beryllium waste mentioned in step one is processing waste, scrapped parts or chips generated during the production process.

[0059] Specific Implementation Method Nine: This implementation method differs from Specific Implementation Methods One to Eight in that the inert gas atmosphere described in step three is argon or a mixture of argon and helium.

[0060] Specific Implementation Method 10: This implementation method differs from Specific Implementation Methods 1 to 9 in that the gas flow rate of the inert gas in step 3 is 10-20 L / min.

[0061] Example 1

[0062] This embodiment describes a method for preparing beryllium-aluminum composite materials using beryllium waste as raw material via arc additive manufacturing, which is carried out according to the following steps:

[0063] 1. Select beryllium-aluminum composite welding wire and perform surface deoxidation and cleaning;

[0064] The cleaning process uses anhydrous ethanol.

[0065] The beryllium-aluminum composite welding wire is made of an aluminum matrix and beryllium particle reinforcement.

[0066] The volume fraction of beryllium particle reinforcement in the beryllium-aluminum composite welding wire is 60%.

[0067] The beryllium particle reinforcement in the beryllium-aluminum composite welding wire has a particle size of 200μm-400μm;

[0068] The composition of the aluminum matrix is: 0.03% Mg, 0.2% Si, 0.2% Fe, 0.01% Mn, 0.02% Cu, 0.05% O, with the balance being Al;

[0069] The diameter of the beryllium-aluminum composite welding wire is 1.2 mm;

[0070] The beryllium particle reinforcement is beryllium waste; beryllium waste is the chips generated during the production process;

[0071] The composition of the beryllium waste is: 3% O, 0.2% Fe, 0.3% Al, 0.3% Mn, 0.2% Si, with the balance being Be;

[0072] The preparation method of the beryllium aluminum composite welding wire is as follows:

[0073] Step (1): Preparation of beryllium / aluminum composite material

[0074] Beryllium / aluminum composites were prepared using a self-venting pressure infiltration method.

[0075] ① After the beryllium particle reinforcement and aluminum matrix are mixed evenly, they are loaded into a steel mold and pressed into a preform. The pressing pressure is 100kN and the holding time is 2min. Then the steel mold containing the preform is placed in a preheating furnace and preheated at 510℃ for 2h.

[0076] ② Melt the aluminum substrate at a temperature of 850℃ to obtain liquid aluminum, and then pour the liquid aluminum into the steel mold that was preheated in step ①;

[0077] ③ The pressure head is applied at 20MPa and moves downward at a speed of 5mm / min, and is held at 30MPa for 3min. Then it is cooled by circulating water to obtain beryllium / aluminum composite material.

[0078] Step (2): Preheating of beryllium / aluminum composite material and hot extrusion die

[0079] First, preheat the beryllium / aluminum composite material to 500℃, and then keep it at 500℃ for 1 hour; keep the hot extrusion die at 50℃ lower than the preheating temperature of the beryllium / aluminum composite material for 1 hour.

[0080] Step (3): Hot extrusion preparation of beryllium / aluminum composite rods

[0081] The preheated beryllium / aluminum composite material is loaded into a hot extrusion die and hot extruded using a press at a rate of 60 mm / min to obtain multiple beryllium / aluminum composite material rods in one go.

[0082] In the extrusion die, the extrusion nozzle is a multi-hole extrusion nozzle with a diameter of 5 mm and a number of 4 holes; the diameter of the preheated beryllium / aluminum composite material is 36 mm;

[0083] Step (4): Annealing treatment of beryllium / aluminum composite rods

[0084] The beryllium / aluminum composite rod obtained in step (3) is heated to 400°C and then kept at 400°C for 2 hours.

[0085] Step (5): Hot spinning forging to prepare beryllium / aluminum composite filaments

[0086] Beryllium / aluminum composite bars are subjected to multi-pass rotary forging using a rotary forging machine. The multi-pass rotary forging process is as follows: the rotary forging temperature is 300℃, the deformation per pass is 10%, the feed rate is 100mm / min, the rotary forging frequency is 50Hz, and annealing is performed after each pass of rotary forging at the same temperature as the rotary forging temperature for 20min.

[0087] 2. Clean the substrate before deposition and then preheat the substrate;

[0088] The method for cleaning the substrate is as follows: first, remove oxides and oil stains from the substrate surface, and then clean the substrate surface with anhydrous ethanol.

[0089] The substrate is preheated at a temperature of 150°C.

[0090] 3. Beryllium aluminum composite material was prepared by layer-by-layer deposition using arc additive manufacturing in an inert gas atmosphere. A variable polarity AC waveform power supply was selected. After each layer was deposited, the beryllium aluminum composite material was cooled to 100°C before the next layer was deposited.

[0091] The process parameters for arc additive manufacturing are as follows: wire extension: 12mm, wire feed speed: 5m / min, welding torch moving speed: 0.5m / min; the positive polarity ratio of the variable polarity AC waveform is 70%, the peak current of the AC waveform is 130A, the voltage is 20V, and the polarity change frequency of the variable polarity AC waveform is 50Hz; the welding torch moving speed can be matched with the welding wire diameter and current to ensure stable droplet transfer.

[0092] The inert gas atmosphere is argon; the inert gas flow rate is 20 L / min.

[0093] Figure 1This is a transmission electron micrograph of the beryllium-aluminum composite material prepared in Example 1. It shows that no beryllium oxide aggregation was observed at the beryllium-aluminum interface, achieving a clean metallurgical bond at the beryllium-aluminum interface and improving the interfacial bonding strength of the beryllium-aluminum composite material. Testing revealed that the beryllium-aluminum composite material prepared in this example has a tensile strength of 415 MPa, a yield strength of 380 MPa, and an elongation of 3.4%, exhibiting good strength and toughness.

[0094] Example 2

[0095] This embodiment describes a method for preparing beryllium-aluminum composite materials using beryllium waste as raw material via arc additive manufacturing, which is carried out according to the following steps:

[0096] 1. Select beryllium-aluminum composite welding wire and perform surface deoxidation and cleaning;

[0097] The cleaning process uses anhydrous ethanol.

[0098] The beryllium-aluminum composite welding wire is made of an aluminum matrix and beryllium particle reinforcement.

[0099] The volume fraction of beryllium particle reinforcement in the beryllium-aluminum composite welding wire is 60%.

[0100] The beryllium particle reinforcement in the beryllium-aluminum composite welding wire has a particle size of 400μm-800μm;

[0101] The composition of the aluminum matrix is: 0.03% Mg, 0.2% Si, 0.2% Fe, 0.02% Mn, 0.03% Cu, 0.1% O, with the balance being Al;

[0102] The diameter of the beryllium-aluminum composite welding wire is 1.2 mm;

[0103] The beryllium particle reinforcement is beryllium waste; beryllium waste is processing residue generated during the production process;

[0104] The composition of the beryllium waste is: 6% O, 0.2% Fe, 0.3% Al, 0.3% Mn, 0.2% Si, with the balance being Be;

[0105] The preparation method of the beryllium aluminum composite welding wire is as follows:

[0106] Step (1): Preparation of beryllium / aluminum composite material

[0107] Beryllium / aluminum composites were prepared using a self-venting pressure infiltration method.

[0108] ① After the beryllium particle reinforcement and aluminum matrix are mixed evenly, they are loaded into a steel mold and pressed into a preform. The pressing pressure is 100kN and the holding time is 2min. Then the steel mold containing the preform is placed in a preheating furnace and preheated at 510℃ for 2h.

[0109] ② Melt the aluminum substrate at a temperature of 850℃ to obtain liquid aluminum, and then pour the liquid aluminum into the steel mold that was preheated in step ①;

[0110] ③ The pressure head is applied at 20MPa and moves downward at a speed of 5mm / min, and is held at 30MPa for 3min. Then it is cooled by circulating water to obtain beryllium / aluminum composite material.

[0111] Step (2): Preheating of beryllium / aluminum composite material and hot extrusion die

[0112] First, preheat the beryllium / aluminum composite material to 500℃, and then keep it at 500℃ for 1 hour; keep the hot extrusion die at 50℃ lower than the preheating temperature of the beryllium / aluminum composite material for 1 hour.

[0113] Step (3): Hot extrusion preparation of beryllium / aluminum composite rods

[0114] The preheated beryllium / aluminum composite material is loaded into a hot extrusion die and hot extruded using a press at a rate of 60 mm / min to obtain multiple beryllium / aluminum composite material rods in one go.

[0115] In the extrusion die, the extrusion nozzle is a multi-hole extrusion nozzle with a diameter of 8 mm and a number of 4 holes; the diameter of the preheated beryllium / aluminum composite material is 36 mm;

[0116] Step (4): Annealing treatment of beryllium / aluminum composite rods

[0117] The beryllium / aluminum composite rod obtained in step (3) is heated to 400°C and then kept at 400°C for 2 hours.

[0118] Step (5): Hot spinning forging to prepare beryllium / aluminum composite filaments

[0119] Beryllium / aluminum composite bars are subjected to multi-pass rotary forging using a rotary forging machine. The multi-pass rotary forging process is as follows: the rotary forging temperature is 300℃, the deformation per pass is 10%, the feed rate is 100mm / min, the rotary forging frequency is 50Hz, and annealing is performed after each pass of rotary forging at the same temperature as the rotary forging temperature for 20min.

[0120] 2. Clean the substrate before deposition and then preheat the substrate;

[0121] The method for cleaning the substrate is as follows: first, remove oxides and oil stains from the substrate surface, and then clean the substrate surface with anhydrous ethanol.

[0122] The substrate is preheated at a temperature of 150°C.

[0123] 3. Beryllium aluminum composite material was prepared by layer-by-layer deposition using arc additive manufacturing in an inert gas atmosphere. A variable polarity AC waveform power supply was selected. After each layer was deposited, the beryllium aluminum composite material was cooled to 100°C before the next layer was deposited.

[0124] The process parameters for arc additive manufacturing are as follows: wire extension: 10mm, wire feed speed: 5m / min, welding torch moving speed: 0.5m / min; the positive polarity ratio of the variable polarity AC waveform is 70%, the peak current of the AC waveform is 140A, the voltage is 21V, and the polarity change frequency of the variable polarity AC waveform is 50Hz; the welding torch moving speed can be matched with the welding wire diameter and current to ensure stable droplet transfer.

[0125] The inert gas atmosphere is argon; the inert gas flow rate is 20 L / min.

[0126] Testing showed that the beryllium aluminum composite material prepared in this embodiment has a tensile strength of 430 MPa, a yield strength of 390 MPa, and an elongation of 3%, exhibiting good strength and toughness.

[0127] Example 3

[0128] This embodiment describes a method for preparing beryllium-aluminum composite materials using beryllium waste as raw material via arc additive manufacturing, which is carried out according to the following steps:

[0129] 1. Select beryllium-aluminum composite welding wire and perform surface deoxidation and cleaning;

[0130] The cleaning process uses anhydrous ethanol.

[0131] The beryllium-aluminum composite welding wire is made of an aluminum matrix and beryllium particle reinforcement.

[0132] The volume fraction of beryllium particle reinforcement in the beryllium-aluminum composite welding wire is 50%.

[0133] The beryllium particle reinforcement in the beryllium-aluminum composite welding wire has a particle size of 200μm-400μm;

[0134] The composition of the aluminum matrix is: 0.04% Mg, 0.2% Si, 0.2% Fe, 0.01% Mn, 0.02% Cu, 0.1% O, with the balance being Al;

[0135] The diameter of the beryllium-aluminum composite welding wire is 1.2 mm;

[0136] The beryllium particle reinforcement is beryllium waste; beryllium waste is processing residue generated during the production process;

[0137] The composition of the beryllium waste is: 3% O, 0.2% Fe, 0.3% Al, 0.3% Mn, 0.2% Si, with the balance being Be;

[0138] The preparation method of the beryllium aluminum composite welding wire is as follows:

[0139] Step (1): Preparation of beryllium / aluminum composite material

[0140] Beryllium / aluminum composites were prepared using a self-venting pressure infiltration method.

[0141] ① After the beryllium particle reinforcement and aluminum matrix are mixed evenly, they are loaded into a steel mold and pressed into a preform. The pressing pressure is 80kN and the holding time is 2min. Then the steel mold containing the preform is placed in a preheating furnace and preheated at 510℃ for 2h.

[0142] ② Melt the aluminum substrate at a temperature of 850℃ to obtain liquid aluminum, and then pour the liquid aluminum into the steel mold that was preheated in step ①;

[0143] ③ The pressure head is applied at 20MPa and moves downward at a speed of 5mm / min, and is held at 30MPa for 3min. Then it is cooled by circulating water to obtain beryllium / aluminum composite material.

[0144] Step (2): Preheating of beryllium / aluminum composite material and hot extrusion die

[0145] First, preheat the beryllium / aluminum composite material to 450℃, and then keep it at 450℃ for 1 hour; keep the hot extrusion die at 50℃ lower than the preheating temperature of the beryllium / aluminum composite material for 1 hour.

[0146] Step (3): Hot extrusion preparation of beryllium / aluminum composite rods

[0147] The preheated beryllium / aluminum composite material is loaded into a hot extrusion die and hot extruded using a press at a rate of 60 mm / min to obtain multiple beryllium / aluminum composite material rods in one go.

[0148] In the extrusion die, the extrusion nozzle is a multi-hole extrusion nozzle with a diameter of 8 mm and a number of 4 holes; the diameter of the preheated beryllium / aluminum composite material is 36 mm;

[0149] Step (4): Annealing treatment of beryllium / aluminum composite rods

[0150] The beryllium / aluminum composite rod obtained in step (3) is heated to 300°C and then kept at 300°C for 2 hours.

[0151] Step (5): Hot spinning forging to prepare beryllium / aluminum composite filaments

[0152] Beryllium / aluminum composite bars are subjected to multi-pass rotary forging using a rotary forging machine. The multi-pass rotary forging process is as follows: the rotary forging temperature is 250℃, the deformation per pass is 10%, the feed rate is 100mm / min, the rotary forging frequency is 50Hz, and annealing is performed after each pass of rotary forging at the same temperature as the rotary forging temperature for 20min.

[0153] 2. Clean the substrate before deposition and then preheat the substrate;

[0154] The method for cleaning the substrate is as follows: first, remove oxides and oil stains from the substrate surface, and then clean the substrate surface with anhydrous ethanol.

[0155] The substrate is preheated at a temperature of 150°C.

[0156] 3. Beryllium aluminum composite material was prepared by layer-by-layer deposition using arc additive manufacturing in an inert gas atmosphere. A variable polarity AC waveform power supply was selected. After each layer was deposited, the beryllium aluminum composite material was cooled to 100°C before the next layer was deposited.

[0157] The process parameters for arc additive manufacturing are as follows: wire extension: 10mm, wire feed speed: 6m / min, welding torch moving speed: 0.6m / min; the positive polarity ratio of the variable polarity AC waveform is 60%, the peak current of the AC waveform is 120A, the voltage is 19V, and the polarity change frequency of the variable polarity AC waveform is 50Hz; the welding torch moving speed can be matched with the welding wire diameter and current to ensure stable droplet transfer.

[0158] The inert gas atmosphere is argon; the inert gas flow rate is 20 L / min.

[0159] Testing showed that the beryllium-aluminum composite material prepared in this embodiment has a tensile strength of 400 MPa, a yield strength of 360 MPa, and an elongation of 4.5%, exhibiting good strength and toughness.

Claims

1. A method for preparing beryllium-aluminum composite materials using beryllium waste as raw material via arc additive manufacturing, characterized in that: The method for preparing beryllium-aluminum composite materials using beryllium waste as raw material via arc additive manufacturing is carried out according to the following steps:

1. Select beryllium-aluminum composite welding wire and perform surface deoxidation and cleaning; The beryllium-aluminum composite welding wire is made of an aluminum matrix and beryllium particle reinforcement. The beryllium particle reinforcement is beryllium waste; The volume fraction of beryllium particle reinforcement in the beryllium-aluminum composite welding wire is 30%-70%.

2. Clean the substrate before deposition and then preheat the substrate; The method for cleaning the substrate is as follows: first, remove oxides and oil stains from the substrate surface, and then clean the substrate surface with anhydrous ethanol or acetone. The substrate is preheated at a temperature of 200-300℃; 3. Beryllium aluminum composite material was prepared by layer-by-layer deposition using arc additive manufacturing in an inert gas atmosphere. A variable polarity AC waveform power supply was selected. After each layer was deposited, the beryllium aluminum composite material was allowed to cool down to 80-150℃ before the next layer was deposited. The process parameters for arc additive manufacturing are as follows: wire extension: 10-15mm, wire feed speed: 2-8m / min, welding torch moving speed: 0.2-0.8m / min; the positive polarity ratio of the variable polarity AC waveform is 40-80%, the peak current of the AC waveform is 100-150A, the voltage is 18-25V, and the polarity change frequency of the variable polarity AC waveform is 50-200Hz.

2. The method for preparing beryllium-aluminum composite materials using beryllium waste as raw material by arc additive manufacturing according to claim 1, characterized in that: The preparation method of the beryllium-aluminum composite welding wire in step one is as follows: Step (1): Preparation of beryllium / aluminum composite material Beryllium / aluminum composites were prepared using a self-venting pressure infiltration method. ① After the beryllium particle reinforcement and aluminum matrix are mixed evenly, they are loaded into a steel mold and pressed into a preform. The pressing pressure is 80-110kN and the holding time is 2-4min. Then the steel mold containing the preform is placed in a preheating furnace and preheated at 510-560℃ for 2h. ② Melt the aluminum substrate at a temperature of 820-860℃ to obtain liquid aluminum, and then pour the liquid aluminum into the steel mold that was preheated in step ①; ③ Apply a pressure of 20-35MPa to the pressure head and move it downward at a speed of 5mm / min. Hold the pressure at 20-35MPa for 3-4 minutes, and then cool it with circulating water to obtain a beryllium / aluminum composite material. Step (2): Preheating of beryllium / aluminum composite material and hot extrusion die First, preheat the beryllium / aluminum composite material to a temperature of 400℃-600℃, and then hold it at a temperature of 400℃-600℃ for 0.5h-6h; the hot extrusion die is held at a temperature 10℃-50℃ lower than the preheating temperature of the beryllium / aluminum composite material for 0.5h-6h. Step (3): Hot extrusion preparation of beryllium / aluminum composite rods The preheated beryllium / aluminum composite material is loaded into a hot extrusion die and hot extruded using a press at a rate of 30-120 mm / min to obtain multiple beryllium / aluminum composite material rods in one operation. In the extrusion die, the extrusion nozzle is a multi-hole extrusion nozzle with a hole diameter of 3mm-10mm and a number of holes of 2-10; the diameter of the preheated beryllium / aluminum composite material is 34-36mm; Step (4): Annealing treatment of beryllium / aluminum composite rods The beryllium / aluminum composite rods obtained in step three are heated to 200-600℃ and then kept at 200-600℃ for 0.5-6 hours. Step (5): Hot spinning forging to prepare beryllium / aluminum composite filaments Beryllium / aluminum composite bars are subjected to multi-pass rotary forging using a rotary forging machine. The multi-pass rotary forging process is as follows: the rotary forging temperature is 200-600℃, the deformation per pass is 1%-10%, the feed rate is 10-200mm / min, the rotary forging frequency is 10-100Hz, and annealing is performed after each rotary forging pass at the same temperature as the rotary forging temperature for 19-21min.

3. The method for preparing beryllium-aluminum composite materials using beryllium waste as raw material by arc additive manufacturing according to claim 1, characterized in that: The cleaning process described in step one uses anhydrous ethanol.

4. The method for preparing beryllium-aluminum composite materials using beryllium waste as raw material by arc additive manufacturing according to claim 1, characterized in that: The beryllium particle reinforcement in the beryllium-aluminum composite welding wire described in step one has a particle size of 10μm-800μm.

5. The method for preparing beryllium-aluminum composite materials using beryllium waste as raw material by arc additive manufacturing according to claim 1, characterized in that: The composition of the aluminum matrix in step one is as follows: Mg 0.01-0.05wt%, Si 0.01-0.25%, Fe 0.01-0.4%, Mn 0.01-0.02%, Cu 0.01-0.04%, O 0.05-0.5%, with the balance being Al.

6. The method for preparing beryllium-aluminum composite materials using beryllium waste as raw material by arc additive manufacturing according to claim 1, characterized in that: The diameter of the beryllium-aluminum composite welding wire mentioned in step one is 1-1.6 mm.

7. The method for preparing beryllium-aluminum composite materials using beryllium waste as raw material by arc additive manufacturing according to claim 1, characterized in that: The composition of the beryllium waste mentioned in step one is: O 0.01-8%, Fe 0.03-2%, Al 0.01-0.5%, Mn 0.01-0.5%, Si 0.01-0.2%, with the balance being Be.

8. The method for preparing beryllium-aluminum composite materials using beryllium waste as raw material by arc additive manufacturing according to claim 1, characterized in that: The beryllium waste mentioned in step one refers to processing surplus, scrapped parts, or chips generated during the production process.

9. The method for preparing beryllium-aluminum composite materials using beryllium waste as raw material by arc additive manufacturing according to claim 1, characterized in that: The inert gas atmosphere described in step three is argon or a mixture of argon and helium.

10. The method for preparing beryllium-aluminum composite materials using beryllium waste as raw material by arc additive manufacturing according to claim 1, characterized in that: Step 3: The inert gas flow rate is 10-20 L / min.

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