An equiaxed crystal high homogeneity titanium-niobium alloy and its arc double-wire additive manufacturing method

Abstract

The present invention belongs to the field of additive manufacturing technology and relates to an equiaxed crystal high-homogeneity titanium-niobium alloy and an arc twin-wire additive manufacturing method thereof. The method installs and fixes pretreated pure titanium wire, pure niobium wire, and a substrate, inputs specific process parameters into the control system of the arc twin-wire additive manufacturing equipment, and performs arc twin-wire deposition through a specific scanning mode to obtain an equiaxed crystal high-homogeneity titanium-niobium alloy. The present invention solves the problem of high niobium inclusions, can promote the uniformity of the composition of the titanium-niobium alloy, facilitates the rapid preparation of the equiaxed crystal high-homogeneity titanium-niobium alloy, is beneficial to the subsequent plastic deformation of the equiaxed crystal high-homogeneity titanium-niobium alloy, can meet the stable production of equiaxed crystal high-homogeneity titanium-niobium alloy products, and ensures the stability of the performance of the components during service.

Description

Technical Field

[0001] The present invention belongs to the technical field of additive manufacturing and relates to an equiaxed crystal highly homogeneous titanium-niobium alloy and an arc twin-wire additive manufacturing method thereof. Background Art

[0002] Titanium-niobium (Ti-Nb) alloy is a metallic material that combines structure and function, and its properties exhibit significant differences depending on the niobium content. When the niobium content ranges from 1 at.% to 29 at.%, Ti-Nb alloy undergoes a thermoelastic martensitic transformation during cooling, exhibiting shape memory properties. This has led to its widespread application in aerospace, medical devices, intelligent structures, and other fields. When the niobium content ranges from 34 at.% to 37 at.%, Ti-Nb alloy exhibits superconducting properties at specific temperatures, making it the alloy of choice for commercially mass-produced superconducting wires. Furthermore, the high-niobium Ti-45wt.%Nb alloy (Ti-45% Nb alloy) exhibits outstanding resistance to galvanic corrosion due to its extremely low galvanic corrosion potential with titanium alloys and other metal-matrix composites. This makes it widely used in aerospace fasteners, providing critical support for the reliability and durability of aircraft structures.

[0003] However, the melting point difference between titanium and niobium is about 800℃, and the traditional casting method is prone to high niobium inclusion problems (such as Figures 2-4 As shown in Figure 2, this poses a significant safety hazard to the stable service life of the product. Using a high-energy electron beam as a heat source to melt titanium-niobium alloys can ensure the full melting of the niobium element, but the significant difference in their melting points leads to volatilization of the titanium, making it impossible to stably produce titanium-niobium alloys with specific compositions. Therefore, achieving a balance between fully melting the high-melting-point niobium and controlling the composition of the titanium-niobium alloy is a pressing challenge in the stable production of titanium-niobium alloys. Summary of the Invention

[0004] The purpose of the present invention is to overcome the shortcomings of the above-mentioned prior art and to provide an equiaxed highly homogeneous titanium-niobium alloy and an arc twin-wire additive manufacturing method thereof.

[0005] In order to achieve the above object, the present invention adopts the following technical solutions:

[0006] An arc twin-wire additive manufacturing method for an equiaxed crystal highly homogeneous titanium-niobium alloy is characterized by installing and fixing pretreated pure titanium wire, pure niobium wire, and a substrate, inputting specific process parameters into a control system of an arc twin-wire additive manufacturing device, and performing arc twin-wire deposition in a specific scanning mode to obtain an equiaxed crystal highly homogeneous titanium-niobium alloy.

[0007] Specifically, this method can fully melt pure niobium wire with a small diameter through a high-energy arc (150A~200A), adjust the melting quality of the pure titanium wire within a reasonably controllable process window, solve the problem of high niobium inclusions, and improve the uniformity of the titanium-niobium alloy composition, thereby realizing the rapid preparation of equiaxed crystal highly homogeneous titanium-niobium alloy; the equiaxed crystal highly homogeneous titanium-niobium alloy prepared by this method has the characteristics of fully equiaxed crystals, ensuring the performance stability of parts made of the equiaxed crystal highly homogeneous titanium-niobium alloy during service.

[0008] The equiaxed highly homogeneous titanium-niobium alloy prepared by this method has a (011) [1-11] orientation characteristic, which belongs to the close-packed plane and close-packed direction of body-centered cubic metal, and is more conducive to the plastic deformation of the titanium-niobium alloy deposited by double-wire arc.

[0009] Furthermore, the method comprises the following steps:

[0010] Step 1: Pretreatment: First, preliminarily treat the surfaces of the pure titanium wire, pure niobium wire, and substrate, and then heat-insulate the pure titanium wire, pure niobium wire, and substrate;

[0011] Step 2: Installation and fixation: Install the pure titanium wire and pure niobium wire on the wire feeding part of the arc twin-wire additive manufacturing equipment, and install the base plate on the CNC forming platform;

[0012] Step 3: Set parameters and mode: Input specific process parameters into the control system of the arc twin-wire additive manufacturing equipment, and perform arc twin-wire deposition using a specific scanning mode to obtain equiaxed, highly homogeneous titanium-niobium alloy.

[0013] Specifically, the method uses pure titanium wire and pure niobium wire as raw materials, and adopts specific process parameters and specific scanning modes through an arc twin-wire additive manufacturing device protected by inert gas to achieve the rapid preparation of equiaxed crystal highly homogeneous titanium-niobium alloy.

[0014] Furthermore, the preliminary surface treatment of the pure titanium wire and the pure niobium wire in step 1 includes: sequentially performing pickling treatment and ultrasonic cleaning on the pure titanium wire and the pure niobium wire;

[0015] The preliminary surface treatment of the substrate in step 1 includes: firstly performing double-sided milling and grinding on the substrate, and then performing surface cleaning on the substrate.

[0016] Specifically, the preliminary surface treatment is to first pickle the pure titanium wire and pure niobium wire to remove the oxide film on the surface of the wire, and then use acetone and other organic solvents to ultrasonically clean them to ensure that the surface of the pure titanium wire and pure niobium wire is free of oil and dirt; secondly, double-sided milling and sandpaper polishing of the substrate are performed to ensure the roughness and smoothness of the substrate surface, and then wipe the substrate surface with alcohol and perform ultrasonic cleaning to completely remove all kinds of oil and impurities on the substrate surface.

[0017] Furthermore, in the step 1, the preliminarily treated pure titanium wire, pure niobium wire and substrate are placed in a drying device at a temperature of 90° C. to 100° C. and kept warm for 25 min to 35 min.

[0018] Specifically, the pure titanium wire, the pure niobium wire and the substrate are placed in a drying device for heat preservation, so that the moisture of the pure titanium wire, the pure niobium wire and the substrate is removed and the residual deformation of the pure titanium wire and the pure niobium wire is eliminated.

[0019] It should be noted that the temperature in the drying equipment can be 90°C, 91°C, 92°C, 93°C, 94°C, 95°C, 96°C, 97°C, 98°C, 99°C, or 100°C, and can be adjusted according to actual needs. The holding time is 25 minutes, 26 minutes, 27 minutes, 28 minutes, 29 minutes, 30 minutes, 31 minutes, 32 minutes, 33 minutes, 34 minutes, or 35 minutes, and can be adjusted according to actual needs. Preferably, the drying equipment is a drying oven, the temperature in the drying oven is maintained at 100°C, and the holding time is 35 minutes.

[0020] Furthermore, in step three, the specific process parameters are set as follows: the current value is 150A~200A, the starting vertical distance between the arc-starting end of the pure titanium wire and the substrate is 7.5mm~8.5mm, the starting vertical distance between the arc-starting end of the pure niobium wire and the substrate is 7.5mm~8.5mm, and the wire feeding speed of the arc twin-wire additive manufacturing equipment is 7mm / s~15mm / s.

[0021] Specifically, the reasons for adopting the specific process parameters are as follows: the preparation method provided by the present invention can fully melt pure niobium wire with a small diameter through a high-energy arc generated by a large current, adjust the melting quality of the pure titanium wire within a reasonable and controllable process window, solve the problem of high niobium inclusions and improve the composition uniformity of the titanium-niobium alloy; and by combining the starting vertical distance between the arc-starting end of the pure titanium wire and the substrate, the starting vertical distance between the arc-starting end of the pure niobium wire and the substrate, and the wire feeding speed of the dual wire feeding nozzle of the arc dual-wire additive manufacturing equipment, the rapid preparation of equiaxed crystal highly homogeneous titanium-niobium alloy is achieved.

[0022] It should be noted that at the beginning of the operation, the starting vertical distances between the arc-starting end of the pure titanium wire and the substrate, and the starting vertical distances between the arc-starting end of the pure niobium wire and the substrate, are both set to 7.5mm to 8.5mm. During the operation, as deposition continues, the vertical distances between the melting tip of the pure titanium wire and the substrate, and the vertical distances between the melting tip of the pure niobium wire and the substrate, gradually increase until the end of the operation, when the final vertical distances between the melting tip of the pure titanium wire and the substrate, and the final vertical distances between the melting tip of the pure niobium wire and the substrate, respectively, reach 9.5mm to 10.5mm. Setting the starting vertical distances ensures that the melting tip of the pure niobium wire is always in the area where the arc energy is most concentrated throughout the operation, providing a sufficient melting temperature.

[0023] It should be noted that the current value can be 150A, 160A, 170A, 180A, 190A, 200A, which can be adjusted according to actual needs. The starting vertical distance between the arc-starting end of the pure titanium wire and the substrate, and the starting vertical distance between the arc-starting end of the pure niobium wire and the substrate can both be 7.5mm, 8mm, and 8.5mm, which can be adjusted according to actual needs. Preferably, the starting vertical distance between the arc-starting end of the pure titanium wire and the substrate, and the starting vertical distance between the arc-starting end of the pure niobium wire and the substrate are both 8mm. The wire feeding speed of the dual wire feeding nozzle of the arc double-wire additive manufacturing equipment can be 7mm / s, 8mm / s, 9mm / s, 10mm / s, 11mm / s, 12mm / s, 13mm / s, 14mm / s, and 15mm / s, which can be adjusted according to actual needs.

[0024] Furthermore, the specific scanning mode is a "single-pass multi-layer round-trip scanning" mode.

[0025] Specifically, the preset three-dimensional model is input into the slicing software, the motion trajectory is automatically generated according to the "single-pass multi-layer-round-trip scanning" mode, and specific process parameters are called in the operation window of the arc twin-wire additive manufacturing equipment.

[0026] Furthermore, the thickness of the substrate is 50 mm to 80 mm.

[0027] Specifically, the thickness of the substrate can be 50 mm, 60 mm, 70 mm, or 80 mm, which can be adjusted according to actual needs. Preferably, the thickness of the substrate is 50 mm.

[0028] Furthermore, the substrate is a Ti-45wt.%Nb alloy substrate.

[0029] Specifically, the Ti-45wt.% Nb alloy substrate enables the rapid preparation of equiaxed, highly homogeneous titanium-niobium alloys. There are two main reasons for selecting a Ti-45wt.% Nb alloy substrate: First, the Ti-45wt.% Nb alloy substrate has a composition close to that of the titanium-niobium alloy prepared by the present invention. This allows the substrate and the prepared equiaxed, highly homogeneous titanium-niobium alloy to be processed and used as a whole without removing the substrate later; second, for arc twin-wire additive manufacturing technology, selecting a substrate with a composition close to that of the equiaxed, highly homogeneous titanium-niobium alloy can effectively alleviate the thermal effect between the bottom equiaxed, highly homogeneous titanium-niobium alloy and the substrate, avoiding cracking caused by a large difference in composition between the two, and ensuring the stable and continuous preparation of the titanium-niobium alloy.

[0030] Furthermore, the diameters of the pure titanium wire and the pure niobium wire are both 1 mm to 1.2 mm.

[0031] Specifically, the diameters of the pure titanium wire and the pure niobium wire can be 1 mm, 1.05 mm, 1.1 mm, 1.15 mm, or 1.2 mm, which can be adjusted according to actual needs. Preferably, the diameters of the pure titanium wire and the pure niobium wire are both 1.2 mm.

[0032] The present invention also provides an equiaxed high-homogeneity titanium-niobium alloy prepared by an arc twin-wire additive manufacturing method of an equiaxed high-homogeneity titanium-niobium alloy, wherein the niobium content is 38wt.%~42wt.%.

[0033] Specifically, the preparation method provided by the present invention achieves controlled niobium content in the titanium-niobium alloy, ensuring the stability of the alloy's performance. The resulting equiaxed, highly homogeneous titanium-niobium alloy is free of high-niobium inclusions and exhibits a uniform microstructure. The niobium content in the equiaxed, highly homogeneous titanium-niobium alloy can be 38 wt.%, 49 wt.%, 40 wt.%, 41 wt.%, or 42 wt.%, and can be adjusted based on actual needs.

[0034] Compared with the prior art, the present invention has the following beneficial effects:

[0035] (1) The present invention fully melts pure niobium wire with a small diameter through a high-energy arc generated by a large current. Under a reasonably controllable process window, the melting quality of the pure titanium wire is adjusted, thereby facilitating the rapid preparation of equiaxed, highly homogeneous titanium-niobium alloys and meeting the requirements for the stable production of titanium-niobium alloy products.

[0036] (2) The present invention overcomes the problem of high niobium inclusions that are easily generated in traditional melting and casting methods, and can improve the uniformity of the titanium-niobium alloy composition. Parts produced using the equiaxed high-homogeneity titanium-niobium alloy prepared by the present invention can always maintain excellent and stable performance during service;

[0037] (3) The equiaxed highly homogeneous titanium-niobium alloy prepared by the present invention has a (011) [1-11] orientation characteristic, which belongs to the close-packed plane and close-packed direction of body-centered cubic metal, and is more conducive to the subsequent plastic deformation of the titanium-niobium alloy. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] The accompanying drawings are incorporated in and constitute a part of this specification and, together with the description, serve to explain the principles of the invention.

[0039] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0040] Figure 1 Schematic diagram of the preparation method of the present invention;

[0041] Figure 2 Schematic diagram of the head cross section of a titanium-niobium alloy containing high niobium inclusions;

[0042] Figure 3 Schematic diagram of the middle cross section of a titanium-niobium alloy containing high niobium inclusions;

[0043] Figure 4 Schematic diagram of the tail cross section of a titanium-niobium alloy containing high niobium inclusions;

[0044] Figure 5 Schematic cross-sectional view of the equiaxed highly homogeneous titanium-niobium alloy in Example 1;

[0045] Figure 6 This is a scanning electron microscope image of the equiaxed crystal highly homogeneous titanium-niobium alloy in Example 1;

[0046] Figure 7 This is a partial enlarged view of region b of the equiaxed highly homogeneous titanium-niobium alloy in Example 1;

[0047] Figure 8 This is a scanning electron microscope image of the niobium distribution of the equiaxed highly homogeneous titanium-niobium alloy in Example 1;

[0048] Figure 9 This is a scanning electron microscope image of the titanium distribution of the equiaxed crystal highly homogeneous titanium-niobium alloy in Example 1;

[0049] Figure 10 This is the solidification orientation map of the equiaxed highly homogeneous titanium-niobium alloy in Example 1;

[0050] Figure 11 2. The solidification orientation pole figure of the equiaxed highly homogeneous titanium-niobium alloy in Example 1;

[0051] Figure 12 2. The solidification orientation inverse pole figure of the equiaxed highly homogeneous titanium-niobium alloy in Example 1;

[0052] Figure 13 The standard projection position diagram of the texture (011) [1-11] of the equiaxed highly homogeneous titanium-niobium alloy in Example 1 on the {100} pole figure;

[0053] Figure 14 This is a grain distribution diagram of the equiaxed highly homogeneous titanium-niobium alloy in Example 1, wherein: the abscissa "Equivalent circular diameter" is the equivalent circular diameter in micrometers; the ordinate "Number" is the numerical value.

[0054] Figure 15 This is the misorientation angle distribution diagram of the equiaxed highly homogeneous titanium-niobium alloy in Example 1, wherein: the Chinese interpretation of the horizontal axis "Misorientation" is the misorientation angle, and the unit is degree; the Chinese interpretation of the vertical axis "Relative frequency" is relative frequency. DETAILED DESCRIPTION

[0055] Here, exemplary embodiments will be described in detail, and the embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present invention. Instead, they are only examples consistent with some aspects of the present invention described in detail in the appended claims.

[0056] The present invention provides an arc twin-wire additive manufacturing method for equiaxed crystal highly homogeneous titanium-niobium alloy. Pretreated pure titanium wire, pure niobium wire, and substrate are installed and fixed, specific process parameters are input into the control system of the arc twin-wire additive manufacturing equipment, and arc twin-wire deposition is performed through a specific scanning mode to obtain equiaxed crystal highly homogeneous titanium-niobium alloy.

[0057] Furthermore, if Figure 1 As shown, the method includes the following steps:

[0058] Step 1: Pretreatment: First, preliminarily treat the surfaces of the pure titanium wire, pure niobium wire, and substrate, and then heat-insulate the pure titanium wire, pure niobium wire, and substrate;

[0059] Step 2: Installation and fixation: Install the pure titanium wire and pure niobium wire on the wire feeding part of the arc twin-wire additive manufacturing equipment, and install the base plate on the CNC forming platform;

[0060] Step 3: Set parameters and mode: Input specific process parameters into the control system of the arc twin-wire additive manufacturing equipment, and perform arc twin-wire deposition using a specific scanning mode to obtain equiaxed, highly homogeneous titanium-niobium alloy.

[0061] In order to enable those skilled in the art to better understand the technical solutions of the present invention, the present invention is described in further detail below with reference to the accompanying drawings and embodiments. Example 1

[0062] This embodiment provides a method for arc twin-wire additive manufacturing of an equiaxed, highly homogeneous titanium-niobium alloy, specifically comprising the following steps:

[0063] Step 1: Pretreatment: First, preliminarily treat the surfaces of the pure titanium wire, pure niobium wire, and substrate, and then heat-insulate the pure titanium wire, pure niobium wire, and substrate;

[0064] Specifically, preliminary surface treatment of the pure titanium wire, pure niobium wire, and substrate was performed, including: first, pickling the pure titanium wire and pure niobium wire with a diameter of 1.2 mm to remove the oxide film on the surface of the wire, and then ultrasonically cleaning them with acetone to ensure that the surfaces of the pure titanium wire and pure niobium wire were free of oil contamination; at the same time, double-sided milling and sandpaper polishing were performed on the Ti-45wt.%Nb alloy substrate with a length of 150 mm, a width of 150 mm, and a thickness of 50 mm to ensure the roughness and smoothness of the substrate surface, and then wiping the substrate surface with alcohol and ultrasonically cleaning it to thoroughly remove all kinds of oil impurities on the substrate surface;

[0065] The pure titanium wire, the pure niobium wire, and the substrate are all subjected to heat preservation, including: placing the pure titanium wire, the pure niobium wire, and the Ti-45wt.%Nb alloy substrate, which have undergone preliminary surface treatment, in a drying oven at 100°C for 25 minutes to remove moisture from the surfaces of the pure titanium wire, the pure niobium wire, and the Ti-45wt.%Nb alloy substrate while eliminating residual deformation of the pure titanium wire and the pure niobium wire;

[0066] Step 2: Installation and fixation: Install the pure titanium wire and pure niobium wire on the wire feeding part of the arc twin-wire additive manufacturing equipment, and install the base plate on the CNC forming platform;

[0067] Specifically, the pure titanium wire and pure niobium wire processed in step 1 are added to the wire feeding part of the arc twin-wire additive manufacturing equipment, and the Ti-45wt.%Nb alloy substrate processed in step 1 is installed on a CNC forming platform that can be moved by CNC;

[0068] Step 3: Setting parameters and modes: Inputting specific process parameters into the control system of the twin-wire arc additive manufacturing equipment, and performing twin-wire arc deposition in a specific scanning mode to obtain equiaxed, highly homogeneous titanium-niobium alloy;

[0069] Specifically, argon gas was first introduced into the wire feeding portion of the arc twin-wire additive manufacturing equipment for protection, and reasonably controllable specific process parameters were input into the arc twin-wire additive manufacturing equipment. The specific process parameters were set as follows: the current value was 200A, the starting vertical distance between the arc striking end of the pure titanium wire and the substrate was 8mm, the starting vertical distance between the arc striking end of the pure niobium wire and the substrate was 8mm, and the wire feeding speed of the arc twin-wire additive manufacturing equipment was 7mm / s.

[0070] Input the preset 3D model into the slicing software, automatically generate the motion trajectory according to the "single-pass multi-layer - round-trip scanning" mode, and call specific process parameters in the arc twin-wire additive manufacturing equipment operation window;

[0071] According to the set control program, arc twin-wire deposition of titanium-niobium alloy was completed to obtain equiaxed crystal highly homogeneous titanium-niobium alloy, wherein the niobium content of the equiaxed crystal highly homogeneous titanium-niobium alloy was 42 wt.%. Example 2

[0072] This embodiment provides a method for arc twin-wire additive manufacturing of an equiaxed, highly homogeneous titanium-niobium alloy, specifically comprising the following steps:

[0073] Step 1: Pretreatment: First, preliminarily treat the surfaces of the pure titanium wire, pure niobium wire, and substrate, and then heat-insulate the pure titanium wire, pure niobium wire, and substrate;

[0074] Specifically, preliminary surface treatment of the pure titanium wire, pure niobium wire, and substrate was performed, including: first, pickling the pure titanium wire and pure niobium wire with a diameter of 1.1 mm to remove the oxide film on the surface of the wire, and then ultrasonically cleaning them with acetone to ensure that the surfaces of the pure titanium wire and pure niobium wire were free of oil contamination; at the same time, double-sided milling and sandpaper polishing were performed on the Ti-45wt.%Nb alloy substrate with a length of 150 mm, a width of 150 mm, and a thickness of 65 mm to ensure the surface roughness and smoothness of the substrate, and then wiping the substrate surface with alcohol and ultrasonically cleaning it to thoroughly remove all kinds of oil impurities on the substrate surface;

[0075] The pure titanium wire, the pure niobium wire, and the substrate are all subjected to heat preservation, including: placing the pure titanium wire, the pure niobium wire, and the Ti-45wt.%Nb alloy substrate, which have undergone preliminary surface treatment, in a drying oven at 95°C for 30 minutes to remove moisture from the pure titanium wire, the pure niobium wire, and the Ti-45wt.%Nb alloy substrate while eliminating residual deformation of the pure titanium wire and the pure niobium wire;

[0076] Step 2: Installation and fixation: Install the pure titanium wire and pure niobium wire on the wire feeding part of the arc twin-wire additive manufacturing equipment, and install the base plate on the CNC forming platform;

[0077] Specifically, the pure titanium wire and pure niobium wire processed in step 1 are added to the wire feeding part of the arc twin-wire additive manufacturing equipment, and the Ti-45wt.%Nb alloy substrate processed in step 1 is installed on a CNC forming platform that can be moved by CNC;

[0078] Step 3: Setting parameters and modes: Inputting specific process parameters into the control system of the twin-wire arc additive manufacturing equipment, and performing twin-wire arc deposition in a specific scanning mode to obtain equiaxed, highly homogeneous titanium-niobium alloy;

[0079] Specifically, argon gas was first introduced into the wire feeding portion of the arc twin-wire additive manufacturing equipment for protection. Reasonable and controllable specific process parameters were then input into the arc twin-wire additive manufacturing equipment. The specific process parameters were set as follows: a current value of 175A, a starting vertical distance between the arc striking end of the pure titanium wire and the substrate of 7.5mm, a starting vertical distance between the arc striking end of the pure niobium wire and the substrate of 7.5mm, and a wire feeding speed of 11mm / s.

[0080] Input the preset 3D model into the slicing software, automatically generate the motion trajectory according to the "single-pass multi-layer - round-trip scanning" mode, and call specific process parameters in the arc twin-wire additive manufacturing equipment operation window;

[0081] According to the set control program, arc twin-wire deposition of titanium-niobium alloy was completed to obtain equiaxed crystal highly homogeneous titanium-niobium alloy, wherein the niobium content of the equiaxed crystal highly homogeneous titanium-niobium alloy was 40 wt.%. Example 3

[0082] This embodiment provides a method for arc twin-wire additive manufacturing of an equiaxed, highly homogeneous titanium-niobium alloy, specifically comprising the following steps:

[0083] Step 1: Pretreatment: First, preliminarily treat the surfaces of the pure titanium wire, pure niobium wire, and substrate, and then heat-insulate the pure titanium wire, pure niobium wire, and substrate;

[0084] Specifically, preliminary surface treatment of the pure titanium wire, pure niobium wire, and substrate was performed, including: first, pickling the pure titanium wire and pure niobium wire with a diameter of 1 mm to remove the oxide film on the surface of the wire, and then ultrasonically cleaning them with acetone to ensure that the surfaces of the pure titanium wire and pure niobium wire were free of oil contamination; at the same time, double-sided milling and sandpaper polishing were performed on the Ti-45wt.%Nb alloy substrate with a length of 150 mm, a width of 150 mm, and a thickness of 80 mm to ensure the surface roughness and smoothness of the substrate, and then wiping the substrate surface with alcohol and ultrasonically cleaning it to thoroughly remove all kinds of oil impurities on the substrate surface;

[0085] The pure titanium wire, the pure niobium wire, and the substrate are all subjected to heat preservation, including: placing the pure titanium wire, the pure niobium wire, and the Ti-45wt.%Nb alloy substrate, which have undergone preliminary surface treatment, in a drying oven at 90°C for 35 minutes to remove moisture from the pure titanium wire, the pure niobium wire, and the Ti-45wt.%Nb alloy substrate while eliminating residual deformation of the pure titanium wire and the pure niobium wire;

[0086] Step 2: Installation and fixation: Install the pure titanium wire and pure niobium wire on the wire feeding part of the arc twin-wire additive manufacturing equipment, and install the base plate on the CNC forming platform;

[0087] Specifically, the pure titanium wire and pure niobium wire processed in step 1 are added to the wire feeding part of the arc twin-wire additive manufacturing equipment, and the Ti-45wt.%Nb alloy substrate processed in step 1 is installed on a CNC forming platform that can be moved by CNC;

[0088] Step 3: Setting parameters and modes: Inputting specific process parameters into the control system of the twin-wire arc additive manufacturing equipment, and performing twin-wire arc deposition in a specific scanning mode to obtain equiaxed, highly homogeneous titanium-niobium alloy;

[0089] Specifically, argon gas was first introduced into the wire feeding portion of the arc twin-wire additive manufacturing equipment for protection, and reasonably controllable specific process parameters were input into the arc twin-wire additive manufacturing equipment. The specific process parameters were set as follows: the current value was 150A, the starting vertical distance between the arc striking end of the pure titanium wire and the substrate was 8.5mm, the starting vertical distance between the arc striking end of the pure niobium wire and the substrate was 8.5mm, and the wire feeding speed of the arc twin-wire additive manufacturing equipment was 15mm / s.

[0090] Input the preset 3D model into the slicing software, automatically generate the motion trajectory according to the "single-pass multi-layer - round-trip scanning" mode, and call specific process parameters in the arc twin-wire additive manufacturing equipment operation window;

[0091] According to the set control program, arc twin-wire deposition of titanium-niobium alloy was completed to obtain equiaxed crystal highly homogeneous titanium-niobium alloy, wherein the niobium content of the equiaxed crystal highly homogeneous titanium-niobium alloy was 38 wt.%.

[0092] Taking the equiaxed, highly homogeneous titanium-niobium alloy deposited by the double-wire arc in Example 1 as an example, the effects of the present invention are analyzed and explained:

[0093] The specific process parameters for depositing equiaxed high-homogeneity titanium-niobium alloy using a twin-wire arc in Example 1 of the present invention include: a current value of 200 A, a starting vertical distance of 8 mm between the arc striking end of the pure titanium wire and the substrate, a starting vertical distance of 8 mm between the arc striking end of the pure niobium wire and the substrate, and a wire feeding speed of 7 mm / s for the twin-wire arc additive manufacturing device. The cross section of the equiaxed high-homogeneity titanium-niobium alloy prepared under these process parameters is as follows: Figure 5 As shown, Figures 2-4 In comparison, the equiaxed highly homogeneous titanium-niobium alloy prepared in Example 1 has a uniform macroscopic morphology and exhibits stable forming characteristics, indicating that the process parameters are well adapted.

[0094] Figures 6-9 The energy spectrum results and microstructure characteristics of the isoaxially oriented highly homogeneous titanium-niobium alloy in Example 1 are presented. The analysis shows that: (1) Figures 6 and 7 As shown in FIG1 , the microstructure of the equiaxed high homogeneous titanium-niobium alloy prepared in Example 1 is characterized by equiaxed crystals, and the niobium content is 42 wt.%; (2) Figures 8 and 9 As shown, in the equiaxed high homogeneity titanium-niobium alloy prepared in Example 1, titanium and niobium elements are evenly distributed, and there is no high niobium inclusion and element segregation phenomenon; Figures 6-9 It can be seen that under reasonable and controllable process parameters, equiaxed highly homogeneous titanium-niobium alloy can be quickly deposited by arc twin-wire.

[0095] Figures 10-15 This is the solidification orientation characteristic of the equiaxed crystal high homogeneity titanium-niobium alloy in Example 1 of the present invention. Figure 10 The large-area solidification orientation map presented fully confirms that the microstructure of the equiaxed highly homogeneous titanium-niobium alloy prepared according to the process parameters of Example 1 is completely equiaxed; Figures 11-13 As shown in the figure, the equiaxed highly homogeneous titanium-niobium alloy exhibits a certain (011) [1-11] orientation characteristic along the deposition direction, which belongs to the close-packed plane and close-packed direction of body-centered cubic metal, which is more conducive to the subsequent plastic deformation of the titanium-niobium alloy.

[0096] like Figure 14 As shown in FIG. 1 , the maximum grain size of the equiaxed highly homogeneous titanium-niobium alloy prepared in Example 1 is 1842.2 μm, the minimum grain size is 17.8 μm, the average grain size is 242.2 μm, and the standard deviation is 220.2 μm. Figure 15 As shown in FIG. 1 , the average orientation difference angle of the equiaxed high homogeneous titanium-niobium alloy prepared in Example 1 is above 30°. Figures 14 and 15 It can be seen that the equiaxed highly homogeneous titanium-niobium alloy has the characteristics of being dominated by large-angle grain boundaries, which is conducive to the subsequent plastic deformation of the equiaxed highly homogeneous titanium-niobium alloy. This shows that by using the arc twin-wire deposition technology under reasonable and controllable process parameters, a fully equiaxed titanium-niobium alloy with a specific orientation and conducive to subsequent plastic deformation can be prepared.

[0097] The foregoing description is intended only to provide specific embodiments of the present invention, which will enable those skilled in the art to understand and implement the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention.

[0098] It should be understood that the present invention is not limited to the above description and that various modifications and changes may be made without departing from the scope thereof. The scope of the present invention is limited only by the appended claims.

Claims

1. A twin-wire arc additive manufacturing method for equiaxed high-homogeneity titanium-niobium alloy, characterized in that: The pre-treated pure titanium wire, pure niobium wire, and substrate are installed and fixed, and specific process parameters are input into the control system of the arc twin-wire additive manufacturing equipment. Arc twin-wire deposition is performed using a specific scanning mode to obtain equiaxed, highly homogeneous titanium-niobium alloy. The method comprises the following steps: Step 1: Pretreatment: First, preliminarily treat the surfaces of the pure titanium wire, pure niobium wire, and substrate, and then heat-insulate the pure titanium wire, pure niobium wire, and substrate; Step 2: Installation and fixation: Install the pure titanium wire and pure niobium wire on the wire feeding part of the arc twin-wire additive manufacturing equipment, and install the base plate on the CNC forming platform; Step 3: Setting parameters and modes: Inputting specific process parameters into the control system of the twin-wire arc additive manufacturing equipment, and performing twin-wire arc deposition in a specific scanning mode to obtain equiaxed, highly homogeneous titanium-niobium alloy; The preliminary surface treatment of the pure titanium wire and the pure niobium wire in step 1 includes: pickling the pure titanium wire and the pure niobium wire and performing ultrasonic cleaning in sequence; The preliminary surface treatment of the substrate in step 1 includes: firstly performing double-sided milling and grinding on the substrate, and then performing surface cleaning on the substrate; In the step 1, the preliminarily treated pure titanium wire, pure niobium wire, and substrate are placed in a drying device at a temperature of 90° C. to 100° C. and kept warm for 25 to 35 minutes; In step 3, the specific process parameters are set as follows: the current value is 150A to 200A, the starting vertical distance between the arc striking end of the pure titanium wire and the substrate is 7.5mm to 8.5mm, the starting vertical distance between the arc striking end of the pure niobium wire and the substrate is 7.5mm to 8.5mm, and the wire feeding speed of the arc twin-wire additive manufacturing equipment is 7mm / s to 15mm / s; The specific scanning mode is a "single-pass multi-layer round-trip scanning" mode; The thickness of the substrate is 50 mm to 80 mm; The substrate is a Ti-45wt.%Nb alloy substrate; The diameters of the pure titanium wire and the pure niobium wire are both 1 mm to 1.2 mm.

2. An equiaxed high homogeneous titanium-niobium alloy prepared by the arc twin-wire additive manufacturing method of the equiaxed high homogeneous titanium-niobium alloy according to claim 1, characterized in that: The niobium content is 38wt.%~42wt.%.

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