Titanium alloy material for 3D printing and preparation method thereof

Abstract

The invention discloses a titanium alloy material for 3D printing and a preparation method thereof.The preparation method comprises the steps that sponge titanium and rare earth yttrium are reduced in the hydrogen atmosphere and mixed with an aluminum-vanadium alloy in a ball-milling mode, then spheroidizing, deoxidizing and alkalizing treatment is conducted, alkalized titanium alloy powder is pretreated in a pretreatment plating solution, and the titanium alloy powder is obtained; and electroplating deposition is carried out in the electroplating liquid, and the spherical deoxidized titanium alloy powder of the shell-core structure is obtained. The spherical titanium alloy powder prepared through the method is small in particle size, good in fluidity, low in hollow rate, high in sphericity degree and particularly suitable for being applied to 3D printing materials.

Description

Technical Field

[0001] The present application relates to the field of metal powder processing, and specifically to a titanium alloy material for 3D printing and a preparation method thereof. Background Art

[0002] Additive Manufacturing (AM), also known as 3D printing technology, integrates computer-aided design, material processing and forming technology, and is based on digital model files. It uses software and CNC systems to stack special metal materials, non-metallic materials and medical biomaterials layer by layer in the form of extrusion, sintering, melting, light curing, spraying, etc. to produce physical objects. Compared with traditional manufacturing technology, additive manufacturing technology has the following characteristics: saving materials, no or little subsequent processing; no need for large-scale forging equipment, molds and special fixtures; can manufacture complex shapes and difficult-to-process materials; personalized design, flexible production; shortened the cycle from design to manufacturing, reduced manufacturing costs and business risks; suitable for parts repair, etc. The emergence of additive manufacturing technology has transformed the processing of metal materials from traditional casting, rolling and cutting to the layer-by-layer accumulation of metals.

[0003] At present, the raw materials used in 3D printing technology are mainly divided into metals, ceramics, polymers and biomaterials. The metal materials used in 3D printing mainly include titanium and titanium alloys, iron-based alloys, high-temperature alloys, aluminum alloys, cobalt-chromium alloys, etc. The raw materials for forming are mostly in the form of powder or wire. Titanium alloys have the advantages of high melting point, high tensile strength, high specific strength, high specific stiffness, strong biocompatibility, non-magneticity, and strong corrosion resistance. They are widely used in aerospace, military industry, shipbuilding industry, automobile industry, petrochemical industry, biomedicine and other fields. However, they have poor thermal conductivity, low plasticity, difficult machining, and long processing cycle. 3D printing technology can well solve the problem of titanium alloy forming and processing, and quickly expand its application field. The use of 3D printing technology to prepare titanium alloy materials for aerospace, civil structures and biomedicine can give full play to the excellent physical and chemical properties of titanium alloys; at the same time, they have the advantages of rapid prototyping and personalized customization of additive manufacturing, so titanium alloy materials for 3D printing have become a hot spot for research in various countries.

[0004] High-quality titanium powder is the basis of titanium alloy 3D printing. Since titanium and titanium alloys are extremely active under high temperature conditions, they are easily reacted with most single substances and compounds and are contaminated. Therefore, it is very difficult to prepare high-purity, high-quality titanium powder. At present, the main problems in the titanium powder preparation process are low fine powder yield, high impurity content, low production efficiency, and poor density. Summary of the invention

[0005] The purpose of the present application is to provide a titanium alloy powder with good fluidity, low hollow rate and high sphericity rate.

[0006] To achieve the above objectives, the technical solution adopted in the present application is: to provide a method for preparing a titanium alloy material for 3D printing, comprising the following preparation steps: S1: reducing a mixture of sponge titanium and yttrium in a hydrogen atmosphere to obtain a hydrogenated sponge titanium with Y2O3 attached to the surface, ball-milling and mixing the hydrogenated sponge titanium with Y2O3 attached to the surface with an aluminum-vanadium alloy, dehydrogenating and diffusing the alloy to obtain a Y2O3 / Ti6Al4V alloy powder; S2: spheroidizing and deoxidizing the Y2O3 / Ti6Al4V alloy powder, removing impurities in an alkaline solution, washing and drying to obtain an alkalized titanium alloy powder; S3: pretreating the alkalized titanium alloy powder in a pretreatment plating solution, filtering, washing and drying to obtain a pretreated titanium alloy powder, placing the pretreated titanium alloy powder in an electroplating solution for electroplating deposition, filtering, washing and drying to obtain a core-shell structure Ni-P@Ti6Al4V spherical deoxidized titanium alloy powder.

[0007] Preferably, the pretreatment plating solution contains nickel sulfate, sodium hypophosphite, sodium citrate and thiourea.

[0008] As another preference, the electroplating solution contains nickel sulfate, sodium hypophosphite, sodium acetate, sodium citrate, citric acid and thiourea.

[0009] As another preferred embodiment, the S2 step is specifically as follows: spheroidizing the Y2O3 / Ti6Al4V alloy powder to obtain spherical Y2O3 / Ti6Al4V alloy powder, adding a deoxidizer for deoxidation treatment to obtain deoxidized spherical Y2O3 / Ti6Al4V titanium alloy powder; removing impurities from the deoxidized spherical Y2O3 / Ti6Al4V titanium alloy powder in an alkaline solution, and then filtering, washing and drying to obtain the alkalized titanium alloy powder.

[0010] As another preference, the deoxidizer is titanium chloride.

[0011] As another preferred embodiment, the Y2O3 / Ti6Al4V alloy powder is subjected to radio frequency plasma spheroidization treatment to obtain the spherical Y2O3 / Ti6Al4V alloy powder.

[0012] As another preferred embodiment, the step S1 is specifically as follows: taking the titanium sponge as a raw material, adding rare earth yttrium, hydrogenating in a hydrogen atmosphere, and obtaining the hydrogenated titanium sponge with Y2O3 attached to the surface; mixing and grinding the hydrogenated titanium sponge with Y2O3 attached to the surface with the aluminum-vanadium alloy particles, dehydrogenating the ground powder, and diffusion alloying to obtain the Y2O 3 / Ti6Al4V alloy powder.

[0013] As another preferred embodiment, the added amount of the rare earth yttrium is 0.3% to 0.5% of the mass of the titanium sponge.

[0014] Further preferably, the pretreatment plating solution comprises 20-40 g / L nickel sulfate, 20-30 g / L sodium hypophosphite, 20-40 g / L sodium citrate and 0.001-0.0005 g / L thiourea, and the electroplating solution comprises 20-40 g / L nickel sulfate, 20-30 g / L sodium hypophosphite, 5-15 g / L sodium acetate, 20-40 g / L sodium citrate, 5-15 g / L citric acid and 0.001-0.0005 g / L thiourea.

[0015] The present application also provides a titanium alloy material for 3D printing, which is prepared by any of the preparation methods described above.

[0016] Compared with the prior art, the beneficial effects of this application are: (1) The present application forms a uniform nickel-phosphorus coating on the surface of the spherical titanium alloy powder. The coating has high hardness and good film properties, which can significantly enhance the strength and hardness of the alloy powder; (2) The spherical titanium alloy powder of the present application is made of high-purity sponge titanium as raw material, rare earth element yttrium is added and calcined in a hydrogen atmosphere. The rare earth element can improve the heat resistance and stability of the alloy, and enhance the strength and hardness of the alloy powder; (3) The present application uses titanium chloride as a deoxidizer, which can refine the grain size of the titanium alloy and strengthen the final material. DETAILED DESCRIPTION

[0017] Below, the present application is further described in conjunction with specific implementation methods. It should be noted that, under the premise of no conflict, the various embodiments or technical features described below can be arbitrarily combined to form new embodiments.

[0018] The terms "including" and "having" and any variations thereof in the specification and claims of this application are intended to cover non-exclusive inclusions. For example, a process, method, system, product or apparatus comprising a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to these processes, methods, products or apparatuses.

[0019] The present application provides a titanium alloy material for 3D printing, which is a core-shell structure Ni-P@Ti6Al4V spherical deoxidized titanium alloy powder, which is obtained by electroplating and depositing spherical Y2O3 / Ti6Al4V titanium alloy powder in an electroplating solution.

[0020] The core-shell structured Ni-P@Ti6Al4V spherical deoxidized titanium alloy powder of the present application is prepared by combining various raw materials and preparation steps. The titanium alloy powder has fine particle size, good fluidity, low hollow rate, low oxygen content, high sphericity, and high density. It has a wide range of application scenarios and is particularly suitable for use in 3D printing materials. The preparation process is simple and easy to operate, and no additional expensive equipment is required, which reduces production costs.

[0021] The electroplating solution is a chemical nickel-phosphorus plating solution, including nickel salt, reducing agent, complexing agent and stabilizer, etc. In some embodiments, the raw materials for preparing the electroplating solution of the present application include: nickel sulfate, sodium hypophosphite, sodium acetate, sodium citrate, citric acid and thiourea.

[0022] It is difficult to prepare composite powders with core-shell structure by ordinary atomization and mechanical alloying methods, while chemical plating is to plate a layer of other metal on the surface of metal powder to make the base powder have the properties of plated metal. The surface modification of powder by chemical plating follows the same principle as bulk plating. The powder is placed in the plating solution, and the surface of each powder will react chemically with the plating solution. The chemical reaction products are deposited on the surface of the powder. After the chemical reaction is completed, a "plating shell" with uniform thickness is formed on the surface of the powder, and finally a composite powder with core-shell structure is formed, completing the surface modification of the powder.

[0023] The present application adopts chemical plating to form a uniform nickel-phosphorus coating on the surface of spherical Y2O3 / Ti6Al4V titanium alloy powder. The coating has uniform thickness, high hardness and good film properties. The nickel-phosphorus coating is coated on the surface of the spherical titanium alloy, which can significantly enhance the strength and hardness of the alloy powder.

[0024] The raw materials for preparing the spherical Y2O3 / Ti6Al4V titanium alloy powder of the present application include hydrogenated titanium sponge with Y2O3 attached to the surface and aluminum-vanadium alloy. The aluminum-vanadium alloy has a small specific surface area and an alloy oxygen content of only 0.12%. The use of the aluminum-vanadium alloy is conducive to the control of the oxygen content of the alloy powder and is conducive to the subsequent diffusion with the titanium alloy.

[0025] The present application provides a method for preparing a hydrogenated sponge titanium raw material with Y2O3 attached to the surface. High-purity sponge titanium is used as the raw material, rare earth element yttrium is added and calcined in a hydrogen atmosphere to obtain hydrogenated sponge titanium with Y2O3 attached to the surface.

[0026] Rare earth elements are lanthanide elements in the periodic table, and yttrium is one of the rare earth elements with a higher content in the earth's crust. Rare earth elements can improve the heat resistance and thermal stability of alloys. The internal oxidation of rare earths forms small and stable ReO particles, which produces dispersion strengthening, reduces the oxygen content and plays a strengthening role. The formation of rare earth oxides changes the surface properties of the powder and the adhesion between powders, reduces the adhesion of powders, reduces the number of satellite powders, and improves the quality of powders. In addition, rare earth oxides are evenly dispersed on the surface of titanium alloys, promoting the formation of a dense protective layer, and greatly improving the strength and hardness of the alloy powder.

[0027] The present application provides a method for preparing a titanium alloy material for 3D printing, comprising the following preparation steps: S1: reducing a mixture of titanium sponge and yttrium in a hydrogen atmosphere to obtain hydrogenated titanium sponge with Y2O3 attached to the surface, mixing the hydrogenated titanium sponge with Y2O3 attached to the surface with an aluminum-vanadium alloy by ball milling, dehydrogenating the mixture and diffusing the alloy to obtain a Y2O3 / Ti6Al4V alloy powder; S2: Spheroidizing and deoxidizing the Y2O3 / Ti6Al4V alloy powder, removing impurities in an alkaline solution, washing and drying to obtain an alkaline titanium alloy powder; S3: pretreating the alkalized titanium alloy powder in a pretreatment plating solution, filtering, washing, and drying to obtain a pretreated titanium alloy powder, placing the pretreated titanium alloy powder in an electroplating solution for electroplating deposition, filtering, washing, and drying to obtain a core-shell structured Ni-P@Ti6Al4V spherical deoxidized titanium alloy powder.

[0028] In some embodiments, step S1 is specifically as follows: using high-purity sponge titanium as a raw material, adding rare earth yttrium, hydrogenating in a hydrogen atmosphere to obtain hydrogenated sponge titanium with Y2O3 attached to the surface; mixing and grinding the hydrogenated sponge titanium with Y2O3 attached to the surface with aluminum-vanadium alloy particles, dehydrogenating the ground powder, and diffusion alloying to obtain Y2O3 / Ti6Al4V alloy powder.

[0029] Since the oxygen content in commercially available titanium hydride powder is as high as 0.2% to 0.3%, and the oxidized titanium hydride powder forms a film on its surface, which hinders the subsequent reaction and also reduces its diffusion rate in the vacuum diffusion process. Therefore, the preparation process of the present application starts with the raw material titanium to prepare titanium hydride. The present application uses large-particle high-purity sponge titanium as raw material, utilizes the reversible reaction of titanium and hydrogen to prepare titanium hydride, and adds the rare earth element yttrium to form an yttrium oxide layer on the surface. The content of hydrogenated sponge titanium oxygen obtained according to the preparation method of the present application is only 0.046%, which is much lower than the oxygen content of commercially available titanium hydride, and is conducive to subsequent reactions.

[0030] In some embodiments, hydrogenated titanium sponge with Y2O3 attached to the surface is mixed with aluminum-vanadium alloy particles in a mass ratio of (10~2): 1. The present application uses coarse aluminum-vanadium alloy particles mixed with hydrogenated titanium sponge with Y2O3 attached to the surface. The coarse aluminum-vanadium alloy particles have a low specific surface area and an alloy oxygen content of only 0.12%. High-purity raw materials are conducive to the control of low oxygen content in fine powder particles and the subsequent diffusion of alloys.

[0031] In some embodiments, step S2 is specifically as follows: subjecting the Y2O3 / Ti6Al4V alloy powder to radio frequency plasma spheroidization treatment to obtain spherical Y2O3 / Ti6Al4V alloy powder, adding a deoxidizer for deoxidation treatment to obtain deoxidized spherical Y2O3 / Ti6Al4V titanium alloy powder; removing impurities from the deoxidized spherical Y2O3 / Ti6Al4V titanium alloy powder in an alkaline solution, and then filtering, washing and drying to obtain an alkalized titanium alloy powder.

[0032] In some embodiments, the deoxidizer is TiCl2, specifically, TiCl2 is added to the spherical Y2O3 / Ti6Al4V alloy powder, and a chlorination deoxidation reaction is carried out at 600-700°C for 0.5-1 h to obtain a deoxidized spherical Y2O3 / Ti6Al4V titanium alloy powder.

[0033] Due to the active chemical properties of titanium, the smaller the particle size of the powdered titanium powder, the easier it is to react with oxygen in the air. Titanium powder with too high oxygen content will cause a surge in sintered blanks during the subsequent sintering process, seriously affecting plasticity. Using Ca or Ho can remove oxygen, but there is an unavoidable problem of residual impurities. The present application uses TiCl2 as a deoxidizer, which forms oxychlorides on the surface of the titanium powder and falls off, achieving deoxidation without introducing other impurities.

[0034] The titanium alloy material of the present application uses large-grain hydrogenated titanium sponge and coarse-grain aluminum-vanadium alloy as raw materials, and undergoes high-energy ball milling, alloy diffusion under an inert atmosphere, and titanium chloride as a deoxidizer for deoxidation. It not only refines the alloy grain size, but also strengthens the final material. The lower oxygen content can also make the synthesized titanium alloy have better plasticity and fatigue resistance. The deoxidized spherical Y2O3 / Ti6Al4V titanium alloy powder can provide a larger specific surface area, more driving force, promote densification, and make the prepared titanium alloy material for 3D printing have better mechanical properties.

[0035] The preparation method of the present application uses a hydrogenation deoxidation method combined with a high-energy ball milling method. The hydrogenated titanium sponge and the aluminum-vanadium alloy form a close metallurgical bond after high-energy ball milling, and vacuum diffusion is used to simultaneously achieve diffusion alloying during the dehydrogenation process. And a spherical titanium alloy powder with high fluidity is obtained by radio frequency plasma spheroidization technology. Compared with the traditional atomization method or the rotating electrode process, this process has the advantages of high output and low cost, and is suitable for expansion and promotion.

[0036] In some embodiments, step S3 is specifically as follows: placing the alkalized titanium alloy powder into a pretreatment plating solution for activation, filtering, washing and drying to obtain a pretreated titanium alloy powder, placing the pretreated titanium alloy powder into an electroplating solution, adjusting the pH and temperature for electroplating deposition, filtering, washing and drying to obtain a core-shell structured Ni-P@Ti6Al4V spherical deoxidized titanium alloy powder.

[0037] In some embodiments, the pretreatment plating solution is a solution containing nickel sulfate, sodium hypophosphite, sodium citrate and thiourea.

[0038] In the technical solution of the present application, the synthesized deoxidized spherical Y2O3 / Ti6Al4V titanium alloy powder is subjected to alkali treatment and chemical plating pre-treatment, which improves the uniformity of the subsequent nickel-phosphorus plating layer, so that a spherical porous structure with alternating dense and sparse layers is formed on the surface of the coating, which is beneficial to the improvement of material strength and plasticity, and enhances the density and plasticity of titanium alloy materials for 3D printing.

[0039] In some embodiments, the electroplating solution is a solution containing nickel sulfate, sodium phosphate, sodium acetate, sodium citrate, citric acid and thiourea. The electroplated core-shell structured Ni-P@Ti6Al4V spherical deoxidized titanium alloy powder has excellent shape memory effect, good mechanical properties, excellent corrosion resistance and biocompatibility, and can be widely used in fields such as biomedical engineering and micro-electromechanical systems.

[0040] In some embodiments, the pH of the electroplating solution is adjusted to 5-6, the temperature is 60-100° C. for electroplating, and the electroplating deposition lasts 10-60 minutes.

[0041] The core-shell structured Ni-P@Ti6Al4V spherical deoxidized titanium alloy powder prepared in this application is prepared by combining multiple preparation methods to produce a titanium alloy powder with small particle size, good fluidity, low hollow rate, low oxygen content, high sphericity, and high density, and has a wide range of application prospects. The preparation process is simple, easy to operate, and low cost.

[0042] Example 1 A titanium alloy material for 3D printing is prepared, comprising the following preparation steps: S1: Using large-particle high-purity sponge titanium as raw material, adding 0.3 wt% rare earth element yttrium, loading into a stainless steel crucible, hydrogenating in a hydrogen reduction furnace at 600 °C for 4 h, obtaining a hydrogenated sponge titanium raw material with Y2O3 attached to the surface; and using coarse-particle aluminum-vanadium alloy as raw material, the hydrogenated sponge titanium with Y2O3 attached to the surface and the coarse-particle aluminum-vanadium alloy were mixed in a ratio of 9:1, crushed by high-energy ball milling under argon conditions, the ball-to-material ratio was 10:1, and the ball milling time was 20 h; then, the crushed powder was dehydrogenated at 700 °C for 80 h, and diffusion alloying was performed to obtain Y2O3 / Ti6Al4V alloy powder; S2: Spherical Y2O3 / Ti6Al4V alloy powder was obtained by radio frequency plasma spheroidization treatment, 1.2 wt% TiCl2 was added and chlorination deoxidation treatment was carried out at 650 ℃ for 30 min to prepare deoxidized spherical Y2O3 / Ti6Al4V titanium alloy powder; the deoxidized spherical Y2O3 / Ti6Al4V titanium alloy powder was allowed to stand in acetone solution for 15 min, and then 1 mol / L sodium hydroxide solution was added and slowly stirred at 40 ℃ for 20 min to remove organic pollutants, and then filtered and washed alternately with deionized water and ethanol for 3 to 4 times, and finally dried in a vacuum drying oven at 60 ℃ for 20 min to obtain alkalized titanium alloy powder; S3: The alkalized titanium alloy powder is placed in a pretreatment plating solution containing 30 g / L nickel sulfate, 25 g / L sodium hypophosphite, 20 g / L sodium citrate and 0.001 g / L thiourea, and the pH is adjusted to about 8.5 with an ammonia solution, and then magnetically stirred for 8 min at a temperature of 65 °C to activate the surface of the titanium alloy powder; then filtered, washed, and dried in a vacuum oven at 60 °C for 20 min for pretreatment; the pretreated titanium alloy powder is added to a Ni-P electroplating solution containing 30 g / L nickel sulfate, 25 g / L sodium hypophosphite, 10 g / L sodium acetate, 20 g / L sodium citrate, 10 g / L citric acid and 0.001 g / L thiourea, the pH is adjusted to about 5.0, and electroplating is carried out at a temperature of 85 °C for 60 min, and then filtered, washed and dried according to the pretreatment process to obtain a core-shell structure Ni-P@Ti6Al4V spherical deoxidized titanium alloy powder.

[0043] Example 2 In step S1, the addition amount of the rare earth element yttrium is adjusted to 0.5 wt %, and the other preparation steps are consistent with the preparation steps in Example 1.

[0044] Example 3 In step S1, the addition amount of TiCl2 is adjusted to 0.8 wt %, and the other preparation steps are consistent with the preparation steps in Example 1.

[0045] Example 4 The composition of the electroplating solution was adjusted to contain 40 g / L nickel sulfate, 25 g / L sodium hypophosphite, 10 g / L sodium acetate, 20 g / L sodium citrate, 10 g / L citric acid and 0.001 g / L thiourea. The other preparation steps were consistent with the preparation steps in Example 1.

[0046] Example 5 The time for electroplating deposition using the electroplating solution was adjusted to 30 min, and the other preparation steps were consistent with the preparation steps in Example 1.

[0047] Comparative Example 1 In step S1, the rare earth element yttrium is not added, and the other preparation steps are consistent with the preparation steps in Example 1.

[0048] Comparative Example 2 In step S2, after the spherical Y2O3 / Ti6Al4V alloy powder is obtained, the chlorination deoxidation step is not performed to prepare the titanium alloy powder of comparative example 2.

[0049] That is, in step S2 of Comparative Example 2, specifically: spherical Y2O3 / Ti6Al4V alloy powder is obtained by radio frequency plasma spheroidization treatment; the spherical Y2O3 / Ti6Al4V titanium alloy powder is allowed to stand in an acetone solution for 15 min, and then 1 mol / L sodium hydroxide solution is added, and slowly stirred at 40°C for 20 min to remove organic pollutants, and then filtered, and washed alternately with deionized water and ethanol for 3 to 4 times, and finally dried in a vacuum drying oven at 60°C for 20 min to obtain an alkalized titanium alloy powder; the other preparation steps are consistent with the preparation steps in Example 1.

[0050] Comparative Example 3 In step S2, after preparing deoxidized spherical Y2O3 / Ti6Al4V titanium alloy powder, the titanium alloy powder of Comparative Example 3 was prepared without using a sodium hydroxide solution for treatment.

[0051] That is, in step S2 of comparative example 3, specifically: spherical Y2O3 / Ti6Al4V alloy powder is obtained by radio frequency plasma spheroidization treatment, 1.2 wt% TiCl2 is added and chlorination deoxidation treatment is performed at 650°C for 30 min to prepare deoxidized spherical Y2O3 / Ti6Al4V titanium alloy powder; In step S3, the deoxidized spherical Y2O3 / Ti6Al4V titanium alloy powder is placed in a pretreatment plating solution for subsequent treatment. The other preparation steps are consistent with the preparation steps in Example 1.

[0052] Comparative Example 4 The Y2O3 / Ti6Al4V alloy powder is spheroidized and deoxidized to obtain deoxidized spherical Y2O3 / Ti6Al4V titanium alloy powder. The subsequent alkalization and electroplating steps are not performed. The other preparation steps are the same as the preparation steps in Example 1, that is, the deoxidized spherical Y2O3 / Ti6Al4V titanium alloy powder is the titanium alloy powder prepared in Comparative Example 4.

[0053] Performance Testing The spherical titanium alloy powders prepared in Examples 1-2 and Comparative Examples 1-2 were tested for oxygen, nitrogen and hydrogen impurities using a LECO ONH836 oxygen, nitrogen and hydrogen analyzer. The results are shown in Table 1.

[0054] Table 1 Analysis results of oxygen, nitrogen and hydrogen contents of titanium alloy powders of Examples 1-2 and Comparative Examples 1-2

[0055] The fluidity and loose density of the spherical titanium alloy powders prepared in Examples 1 to 5 and Comparative Examples 1 to 4 were determined by using Dandong Better BT-200 powder property tester in accordance with the national standards GB / T1482-2022 and GB / T1479.1-2011, and the average value was taken after 5 measurements. The morphology of the spherical titanium alloy powders prepared in Examples 1 to 5 and Comparative Examples 1 to 4 was observed by using a JSM-6 460 scanning electron microscope, and the sphericity and hollowness were obtained by nano-measurer. The results are shown in Table 2.

[0056] Table 2 Performance test results of various embodiments and comparative examples

[0057] The size of the bulk density reflects the size of the gaps between the powder particles and the degree of stacking. Therefore, when the bulk density is smaller, it means that the gaps between the powder particles are larger and the stacking is looser. Analysis of the performance test results in Table 2 shows that alkali treatment and electroplating coating of the prepared titanium alloy powder can reduce the bulk density of the final product titanium alloy, making the gaps between the titanium alloy powder particles larger and the stacking looser.

[0058] The fluidity of titanium alloy powder refers to the smoothness of the powder during the flow process, which has an important impact on the processing and application of the powder. The lower the fluidity, the greater the resistance of the powder during the flow process, and the worse the flow performance of the powder. The titanium alloy material prepared in this application has good fluidity.

[0059] Titanium alloy powders with high sphericity have better fluidity, which helps achieve more uniform powder spreading during 3D printing, thereby improving the quality of printed parts. Powders with high hollowness are prone to hole defects during 3D printing, which may become crack sources and affect the mechanical properties and durability of the material. Hollow powders have poor structural integrity due to the presence of internal cavities, which may cause powder or formed parts to break during subsequent heat treatment or machining.

[0060] In titanium alloy powders for 3D printing, high sphericity and low hollowness are key factors in improving the quality of printed parts. Sphericity and hollowness directly affect the fluidity, energy absorption, density of the powder, as well as the porosity and mechanical properties of the final product. Therefore, in the field of 3D printing, there are strict requirements on the sphericity and hollowness of titanium alloy powders. The titanium alloy material for 3D printing of the present application has good sphericity and hollowness, and is suitable for application in the field of 3D printing.

[0061] In summary, the present application provides a titanium alloy material for 3D printing and a preparation method thereof. The titanium alloy material is prepared by combining a variety of raw materials and preparation steps to obtain a titanium alloy powder with good fluidity, low hollow rate, and high sphericity, which is particularly suitable for use in 3D printing materials.

[0062] The above describes the basic principles, main features and advantages of the present application. Those skilled in the art should understand that the present application is not limited by the above embodiments, and the above embodiments and the specification only describe the principles of the present application. The present application may have various changes and improvements without departing from the spirit and scope of the present application, and these changes and improvements fall within the scope of the present application for which protection is sought. The scope of protection claimed by the present application is defined by the attached claims and their equivalents.

Claims

1. A method for preparing a titanium alloy material for 3D printing, characterized in that: The method comprises the following preparation steps: S1: reducing a mixture of titanium sponge and yttrium in a hydrogen atmosphere to obtain hydrogenated titanium sponge with Y2O3 attached to the surface, mixing the hydrogenated titanium sponge with Y2O3 attached to the surface with an aluminum-vanadium alloy by ball milling, dehydrogenating the mixture and diffusing the alloy to obtain a Y2O3 / Ti6Al4V alloy powder; S2: spheroidizing and deoxidizing the Y2O3 / Ti6Al4V alloy powder, removing impurities in an alkaline solution, washing and drying to obtain an alkaline titanium alloy powder; S3: pretreating the alkalized titanium alloy powder in a pretreatment plating solution, filtering, washing, and drying to obtain a pretreated titanium alloy powder, placing the pretreated titanium alloy powder in an electroplating solution for electroplating deposition, filtering, washing, and drying to obtain a core-shell structured Ni-P@Ti6Al4V spherical deoxidized titanium alloy powder.

2. The preparation method according to claim 1, characterized in that The pretreatment plating solution contains nickel sulfate, sodium hypophosphite, sodium citrate and thiourea.

3. The preparation method according to claim 2, characterized in that: The electroplating solution contains nickel sulfate, sodium hypophosphite, sodium acetate, sodium citrate, citric acid and thiourea.

4. The preparation method according to claim 1, characterized in that: The S2 step specifically comprises: spheroidizing the Y2O3 / Ti6Al4V alloy powder to obtain spherical Y2O3 / Ti6Al4V alloy powder, adding a deoxidizer for deoxidation treatment to obtain deoxidized spherical Y2O3 / Ti6Al4V titanium alloy powder; removing impurities from the deoxidized spherical Y2O3 / Ti6Al4V titanium alloy powder in an alkaline solution, and then filtering, washing and drying to obtain the alkalized titanium alloy powder.

5. The preparation method according to claim 4, characterized in that: The deoxidizer is titanium chloride.

6. The preparation method according to claim 4, characterized in that: The Y2O3 / Ti6Al4V alloy powder is subjected to radio frequency plasma spheroidization treatment to obtain the spherical Y2O3 / Ti6Al4V alloy powder.

7. The preparation method according to claim 1, characterized in that: The step S1 specifically comprises: taking the titanium sponge as a raw material, adding rare earth yttrium, and hydrogenating in a hydrogen atmosphere to obtain the hydrogenated titanium sponge with Y2O3 attached to the surface; mixing and grinding the hydrogenated titanium sponge with Y2O3 attached to the surface with the aluminum-vanadium alloy particles, dehydrogenating the ground powder, and diffusion alloying to obtain the Y2O3 3 / Ti6Al4V alloy powder.

8. The preparation method according to claim 7, characterized in that: The added amount of the rare earth yttrium is 0.3% to 0.5% of the mass of the sponge titanium.

9. The preparation method according to claim 3, characterized in that: The pretreatment plating solution includes 20-40 g / L nickel sulfate, 20-30 g / L sodium hypophosphite, 20-40 g / L sodium citrate and 0.001-0.0005 g / L thiourea, and the electroplating solution includes 20-40 g / L nickel sulfate, 20-30 g / L sodium hypophosphite, 5-15 g / L sodium acetate, 20-40 g / L sodium citrate, 5-15 g / L citric acid and 0.001-0.0005 g / L thiourea.

10. A titanium alloy material for 3D printing, characterized in that: Prepared by any preparation method of claims 1 to 9.

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