A technology for preparing ultra-high strength and toughness pure titanium materials based on titanium waste

Abstract

This invention provides a technology for preparing ultra-high strength and toughness pure titanium materials based on titanium waste, relating to the technical field of titanium waste recycling. The technology uses pure titanium waste as raw material, and through powdering, forming, sintering, and thermomechanical treatment, prepares ultra-high strength and toughness pure titanium with a tensile strength ≥900MPa and an elongation ≥11%. It eliminates the need for traditional alloying elements such as Al, V, Mo, Zr, Cr, and Ta; by simply controlling the interstitial elements in the recycled powder, a synergistic match of ultra-high strength and high plasticity can be achieved in the recycled pure titanium. This invention significantly expands the tolerance range of pure titanium materials to oxygen content, increasing the acceptable oxygen content from no more than 0.33wt.% in traditional engineering applications to 1.1wt.%, greatly reducing the purity requirements for raw materials in titanium waste recycling, lowering recycling difficulty and manufacturing costs, and showing broad application prospects in the field of green and low-cost titanium material manufacturing.

Description

Technical Field

[0001] This invention relates to the technical field of titanium waste recycling, and in particular to a technology for preparing ultra-high strength and toughness pure titanium materials based on titanium waste. Background Technology

[0002] Pure titanium and its alloys possess high specific strength and excellent corrosion resistance, making them widely used in aerospace, marine engineering, and other structural fields with high requirements for lightweighting and corrosion resistance. Currently, in engineering applications, commercial titanium alloy components are typically manufactured through two methods: additive manufacturing, which requires strict purity of raw materials; and traditional processes such as casting or powder metallurgy combined with subsequent machining. The former easily generates titanium waste with high oxygen content during manufacturing, significantly increasing production costs; the latter generates a large amount of titanium chips during machining, resulting in low material utilization.

[0003] These waste titanium materials are often used in iron-based smelting in industrial production. Due to their high interstitial element content, they are difficult to directly recycle for the production of high-performance titanium materials. Typically, when the oxygen content in pure titanium increases, although the yield strength and tensile strength increase significantly, the plasticity decreases sharply. This is because the strong interaction between interstitial oxygen and dislocations in titanium leads to increased brittleness. According to industry design standards, the oxygen content in titanium alloys should generally not exceed 0.3 wt.%; when this value is exceeded, the material's plasticity can drop below 2%, making it difficult to meet service requirements. However, titanium waste is easily contaminated by oxygen during hot working and machining, and its oxygen content generally exceeds 0.3 wt.%. Therefore, to achieve the industrialization of ultra-high strength and toughness pure titanium under low-cost, alloy-free conditions, it is essential to effectively control the distribution of interstitial oxygen and avoid oxygen embrittlement. Currently, regardless of whether casting, forging, or powder metallurgy processes are used, the efficient recycling of titanium waste remains a pressing problem that needs to be solved.

[0004] Chinese patent CN120026213A discloses a method for preparing ultra-high strength and toughness TC4 titanium alloy based on titanium waste. This method has the following drawbacks: strong dependence on alloy system, insufficient applicability to high oxygen pure titanium waste, mismatch between strengthening path and pure titanium material, and complex process and high energy consumption due to multiple solid solution and aging treatments.

[0005] Chinese patent CN110184628A discloses a method for preparing low-oxygen high-purity titanium powder using industrial waste titanium. This method has technical defects such as obvious deoxygenation and purification orientation, long process flow and high equipment requirements, only able to obtain powder and difficult to directly prepare high-density bulk materials, and the acid washing and molten salt electrolysis steps bring great corrosion and environmental pressure.

[0006] Chinese patent CN116463568A discloses a method for recycling titanium waste. This method has technical defects such as obvious deoxygenation and powdering orientation, lengthy and complex process flow, easy introduction of impurities and increased difficulty in oxygen control during wet granulation and multiple crushing processes, and difficulty in directly preparing high-density, high-strength and high-toughness bulk pure titanium.

[0007] Therefore, there is an urgent need to develop a technology for preparing ultra-high strength and toughness pure titanium materials based on titanium waste, so as to obtain pure titanium materials with both ultra-high strength and high plasticity, and realize the high-value utilization of titanium waste. Summary of the Invention

[0008] The main objective of this invention is to address the challenges posed by high oxygen content in the recycling of titanium and titanium alloy waste. High oxygen content leads to a significant decrease in material plasticity, making it prone to brittle fracture and hindering direct recycling. Existing recycling methods typically reduce oxygen content by diluting the waste with large amounts of low-oxygen titanium or by adding elements such as Ca, Mg, and Re at high temperatures to induce an oxygen fixation reaction. However, these methods suffer from technical problems such as complex processes, high costs, low recovery rates, and unstable product performance. Therefore, this invention proposes a technology for preparing ultra-high strength and toughness pure titanium materials from titanium waste, which can solve the aforementioned problems.

[0009] The technical solution is as follows:

[0010] A technology for preparing ultra-high strength and toughness pure titanium materials based on titanium waste, wherein the specific steps of the technology for preparing ultra-high strength and toughness pure titanium materials based on titanium waste are as follows:

[0011] S1. Titanium waste treatment: Commercially available pure titanium waste is automatically conveyed into an ultrasonic cleaner for ultrasonic cleaning; after cleaning, the waste is automatically transported to a clean water tank for secondary rinsing, and then enters a drying device for drying, finally obtaining pure titanium waste with a clean surface.

[0012] S2, Hydrogenation and Dehydrogenation Treatment: The clean titanium waste obtained in step S1 is fed into a hydrogenation-dehydrogenation equipment for hydrogenation. The hydrogenation process ends when the hydrogen absorption is controlled between 3.0-4.0 wt.%. The resulting hydrogenated material is fully crushed by high-energy ball milling and then dehydrogenated after sieving to obtain pure titanium powder.

[0013] S3. Cold isostatic pressing: The pure titanium powder obtained in step S2 is placed into a cold isostatic pressing sleeve, and after compaction, it is sealed. Then, the powder filling mold is placed in the cold isostatic pressing device for pressing and forming. After pressing, the mold is demolded to obtain a pure titanium compact.

[0014] S4. Vacuum sintering: The pure titanium billet obtained in step S3 is placed in a vacuum sintering furnace and sintered under vacuum conditions. After sintering, it is cooled to room temperature with the furnace to obtain a pure titanium sintered billet.

[0015] S5. Hot working deformation: The pure titanium sintered billet obtained in step S4 is placed in a resistance heating furnace for heating and holding. After the holding period, the sample is taken out and hot deformation processing is carried out by forging, extrusion or rolling to obtain pure titanium products.

[0016] S6. First α hot deformation treatment: The pure titanium product obtained in step S5 is heated and kept at a constant temperature, and then hot deformation processing is carried out by forging, extrusion or rolling to obtain a pure titanium product in one cycle.

[0017] S7. Cyclic α-thermal deformation treatment: The pure titanium product obtained from one cycle in S6 is subjected to multiple cycles of thermomechanical treatment. The thermomechanical treatment process is the same as that in S6, resulting in pure titanium material that has undergone multiple cycles.

[0018] Optionally, in S1, ultrasonic cleaning is performed at 50-90℃ using water as the cleaning medium at 20-50kHz for 20-100min, and the oil and impurities on the surface of the titanium waste are fully decomposed and removed through segmented cleaning; the process parameters for the secondary rinsing are deionized water rinsing, rinsing temperature 20-40℃, and rinsing time 5-15min; the process parameters for drying are drying at 80-120℃ for 30-120min, hot air circulation drying, or vacuum drying; the oxygen content of the clean pure titanium waste is >0.3wt.% and <1.1wt.%.

[0019] Optionally, the hydrogenation temperature in S2 is 350-550℃; the high-energy ball milling speed is 200-500 rpm, and the time is 5-20 h; the sieve mesh size is 350 mesh; the dehydrogenation temperature is 650-750℃, and the dehydrogenation time is 2-6 h; the oxygen content of the pure titanium powder is >0.45wt.% and <1.1wt.%, the hydrogen content is ≤0.5wt.%, the powder particle size is 0-25μm, and D50 <10μm.

[0020] Optionally, the oxygen content of the pure titanium powder in S2 is mainly determined by the oxygen content of the titanium waste itself; if the oxygen content does not meet the required range, TiO2 needs to be added to adjust the oxygen content to the required range.

[0021] Optionally, the pressure applied during S3 is 200-450 MPa, and the holding time is 60-350 s.

[0022] Optionally, in S4, the vacuum degree is 10 -1 -10 -3 Sintering is carried out under Pa conditions, with the sintering temperature controlled between 1100-1200℃ and held for 1-4 hours; the density of the pure titanium sintered billet is >96%, and the average grain size is <30μm.

[0023] Optionally, before hot working deformation in S5, it is necessary to heat to 1100-1250℃ and hold for 1-2 hours; the deformation amount of hot working deformation needs to be controlled at 30-50%; the density of pure titanium products is >99%, the oxygen content is ≥0.5wt.% and ≤1.1wt.%, and the average grain size is ≤40μm.

[0024] Optionally, the temperature for the heating and heat preservation treatment in S6 is 860-960℃, and the heat preservation time is 1-10min; the deformation amount per cycle is controlled at 5-15%; the oxygen content of the pure titanium product in one cycle is ≥0.5wt.% and ≤1.1wt.%, and the average grain size is ≤20μm.

[0025] Optionally, the number of cycles in S7 is determined by the oxygen content of pure titanium. Once the oxygen content is >0.9wt.%, the number of cycles is ≥6, and the prepared pure titanium material has a density >99.9%, tensile strength ≥900MPa, yield strength ≥750MPa, yield ratio ≥0.81, elongation ≥11%, and strength-ductility product ≥10GPa.

[0026] Optionally, the methods described in S1-S7 are not limited to the recycling of pure titanium waste, but are also applicable to the recycling of other α and α+β series titanium alloy waste.

[0027] Technical principle of the invention:

[0028] This invention proposes a novel method for recycling titanium waste based on thermomechanical treatment and interstitial element regulation. This method produces ultra-high strength and toughness pure titanium without the need for costly removal of interstitial oxygen. It fully utilizes the controllable adjustment of the distribution and bonding state of interstitial oxygen in the titanium matrix to achieve a match between ultra-high strength and high plasticity in high-oxygen pure titanium. It does not require the addition of alloying strengthening elements such as Al, V, Mo, Zr, Cr, and Ta, nor does it require costly deep deoxidation treatment. It can achieve a tensile strength ≥1100MPa and an elongation ≥10%.

[0029] This invention uses only water as the cleaning medium in the pure titanium waste cleaning stage. Cutting oil, lubricating oil and processing residues on the surface of pure titanium waste can be effectively removed through ultrasonic cleaning and segmented rinsing. No acid, alkali or organic solvents are needed, and no chemical waste liquid is generated. The process is green and environmentally friendly, which is conducive to realizing continuous and large-scale industrial production.

[0030] This invention eliminates the need to mix and dilute high-oxygen pure titanium with a large amount of low-oxygen pure titanium, and also eliminates the need to add elements such as Ca, Mg, and Re under high-temperature conditions for oxygen fixation and deoxidation treatment. It saves on complex chemical reactions, secondary refining, and waste residue treatment processes, making the process flow simpler and significantly reducing energy consumption and overall recycling costs.

[0031] This invention retains the original high oxygen content in pure titanium waste during the waste treatment stage, providing the necessary conditions for the regulation and utilization of interstitial oxygen in subsequent processes. This allows pure titanium materials to adopt a strengthening design path of "preserving oxygen rather than removing oxygen", breaking through the technical limitation of traditional recycling processes that require reducing oxygen content to ensure plasticity.

[0032] This invention performs initial densification treatment on high-oxygen pure titanium sintered billets through high-temperature hot working, thereby improving the overall density of the material. During this process, the distribution of interstitial oxygen near dislocations and interfaces is controlled, providing favorable initial microstructure conditions for subsequent multi-pass α-hot deformation treatment.

[0033] This invention introduces and stabilizes a large number of dislocation structures in a pure titanium matrix through multi-pass cyclic thermomechanical treatment in the α phase region. This allows interstitial oxygen and dislocations to work synergistically, weakening the short-range strong resistance effect of interstitial oxygen on dislocation movement, thereby significantly reducing the risk of brittle fracture of pure titanium materials under high oxygen conditions.

[0034] This invention induces the formation of local structural units that are conducive to accommodating interstitial elements during cyclic α-thermal deformation and strengthens the interface structure. While making full use of the solid solution strengthening effect of interstitial elements, it achieves a synergistic improvement in the strength and plasticity of pure titanium materials.

[0035] This invention effectively refines grains and stabilizes microstructure through multi-stage α-thermal deformation treatment, resulting in high-oxygen pure titanium material with dense microstructure, fine grains, small performance fluctuations, high product consistency and stability, making it suitable for use in engineering structural components.

[0036] This invention significantly expands the tolerance range of pure titanium materials to oxygen content, enabling pure titanium to still obtain excellent comprehensive mechanical properties even when the oxygen content is increased from no more than 0.3 wt.% in traditional engineering applications to 1.1 wt.%, greatly reducing the requirements for the purity of the original waste material.

[0037] This invention eliminates the need for adding reinforcing alloying elements such as Al, V, Mo, Zr, Cr, Nb, and Ta. Through process design alone, pure titanium materials can achieve significantly improved strength while maintaining good plasticity, resulting in a tensile strength of not less than 900 MPa and an elongation of not less than 11%.

[0038] The above technical solution has at least the following advantages compared with the existing technology:

[0039] The above-described solution proposes a technology for preparing ultra-high strength and toughness pure titanium materials from titanium waste. This technology effectively solves the problem that during the recycling of titanium and titanium alloy waste, the high oxygen content leads to a significant decrease in material plasticity, easy brittle fracture, and difficulty in direct recycling. Existing recycling methods typically reduce oxygen content by mixing and diluting with a large amount of low-oxygen titanium, or by adding elements such as Ca, Mg, and Re under high-temperature conditions to carry out an oxygen fixation reaction. However, these methods suffer from technical problems such as complex processes, high costs, low recovery rates, and unstable performance of the resulting products.

[0040] Unlike existing complex processes that involve diluting with large amounts of low-oxygen titanium or using high-temperature oxygen removal with elements such as Ca, Mg, and Re, this invention achieves controllable regulation of the distribution and bonding state of interstitial oxygen in the titanium matrix through a combination of thermomechanical treatment and interstitial element control. This fundamentally weakens the short-range strong coupling between oxygen and dislocations and significantly reduces oxygen embrittlement sensitivity.

[0041] This method does not require the addition of high-cost alloying elements such as Al, V, Mo, Zr, Cr, and Ta, nor does it require a deep deoxidation process. It can fully utilize the interstitial oxygen strengthening effect inherent in titanium waste, thereby achieving ultra-high strength while maintaining good plasticity.

[0042] The high-oxygen pure titanium prepared by the method of this invention has a tensile strength of over 900 MPa and an elongation of not less than 11%. It achieves a synergistic improvement in strength and plasticity under non-alloying conditions, breaking through the inherent limitation of traditional high-oxygen titanium materials that "strength improvement is accompanied by loss of plasticity".

[0043] The process of this invention is simple, energy-efficient, and low-cost. It does not require acid-base chemical deoxidation and the production process is clean and environmentally friendly. It has significant potential for industrial application and promotion value, and provides a green, low-carbon, and sustainable new technology path for the high-value regeneration of high-oxygen titanium waste.

[0044] This invention is not limited to the recycling of pure titanium, but is also applicable to the recycling and utilization of other α and α+β series titanium alloy wastes such as Ti-6Al-4V, Ti-6Al, Ti-5Al-2.5Sn and Ti-6Al-2Sn-4Zr-2Mo.

[0045] This invention, through the process concept of "oxygen preservation-regulation-utilization", transforms interstitial oxygen, which was originally considered a detrimental factor, into a usable enhanced resource, thereby achieving high-value recycling and efficient resource recycling of pure titanium waste, which is in line with the development trend of low-carbon, energy-saving and green manufacturing.

[0046] In summary, compared with traditional methods, the proposed pure titanium waste treatment process combines high-temperature hot deformation technology with multi-stage cyclic thermomechanical treatment in the α-phase region, achieving the preparation of ultra-high strength and toughness pure titanium materials. Furthermore, by subjecting pure titanium to multiple cyclic α-hot deformation treatments under high oxygen conditions, the interstitial oxygen in the pure titanium matrix can be controlled and adjusted, significantly expanding the tolerance range of pure titanium materials to oxygen content. Without the need to add any alloying strengthening elements or perform costly deep deoxidation treatment, this invention can obtain pure titanium materials with both high strength and high plasticity. The method is flexible, easy to operate, and widely applicable, making it suitable for low-cost, high-efficiency industrial recycling and large-scale production of pure titanium waste. Attached Figure Description

[0047] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0048] Figure 1 This is a process flow diagram of a technology for preparing ultra-high strength and toughness pure titanium materials based on titanium waste according to the present invention. Detailed Implementation

[0049] The technical solution of the present invention will now be described with reference to the accompanying drawings.

[0050] In embodiments of the present invention, words such as "exemplarily," "for example," etc., are used to indicate that something is an example, illustration, or description. Any embodiment or design described as "exemplary" in the present invention should not be construed as being more preferred or advantageous than other embodiments or designs. Specifically, the use of the word "exemplary" is intended to present the concept in a concrete manner. Furthermore, in embodiments of the present invention, the meaning expressed by "and / or" can be both, or either one.

[0051] In the embodiments of the present invention, the terms "image" and "picture" may sometimes be used interchangeably. It should be noted that when the distinction is not emphasized, their intended meanings are consistent.

[0052] In this embodiment of the invention, sometimes a subscript such as W1 may be written in a non-subscript form such as W1. When the difference is not emphasized, the meaning they express is the same.

[0053] To make the technical problems, technical solutions and advantages of the present invention clearer, a detailed description will be given below in conjunction with the accompanying drawings and specific embodiments.

[0054] A technology for preparing ultra-high strength and toughness pure titanium materials based on titanium waste, wherein the technology for preparing ultra-high strength and toughness pure titanium materials based on titanium waste is combined with Figure 1 The specific steps are as follows:

[0055] S1. Titanium waste treatment: Commercially available pure titanium waste is automatically conveyed into an ultrasonic cleaner for ultrasonic cleaning; after cleaning, the waste is automatically transported to a clean water tank for secondary rinsing, and then enters a drying device for drying, finally obtaining pure titanium waste with a clean surface.

[0056] S2, Hydrogenation and Dehydrogenation Treatment: The clean titanium waste obtained in step S1 is fed into a hydrogenation-dehydrogenation equipment for hydrogenation. The hydrogenation process ends when the hydrogen absorption is controlled between 3.0-4.0 wt.%. The resulting hydrogenated material is fully crushed by high-energy ball milling and then dehydrogenated after sieving to obtain pure titanium powder.

[0057] S3. Cold isostatic pressing: The pure titanium powder obtained in step S2 is placed into a cold isostatic pressing sleeve, and after compaction, it is sealed. Then, the powder filling mold is placed in the cold isostatic pressing device for pressing and forming. After pressing, the mold is demolded to obtain a pure titanium compact.

[0058] S4. Vacuum sintering: The pure titanium billet obtained in step S3 is placed in a vacuum sintering furnace and sintered under vacuum conditions. After sintering, it is cooled to room temperature with the furnace to obtain a pure titanium sintered billet.

[0059] S5. Hot working deformation: The pure titanium sintered billet obtained in step S4 is placed in a resistance heating furnace for heating and holding. After the holding period, the sample is taken out and hot deformation processing is carried out by forging, extrusion or rolling to obtain pure titanium products.

[0060] S6. First α hot deformation treatment: The pure titanium product obtained in step S5 is heated and kept at a constant temperature, and then hot deformation processing is carried out by forging, extrusion or rolling to obtain a pure titanium product in one cycle.

[0061] S7. Cyclic α-thermal deformation treatment: The pure titanium product obtained from one cycle in S6 is subjected to multiple cycles of thermomechanical treatment. The thermomechanical treatment process is the same as that in S6, resulting in pure titanium material that has undergone multiple cycles.

[0062] Specifically, in S1, ultrasonic cleaning is performed at 50-90℃ using water as the cleaning medium at 20-50kHz for 20-100 minutes. The oil and impurities on the surface of the titanium waste are fully decomposed and removed through segmented cleaning. The process parameters for the secondary rinsing are deionized water rinsing, rinsing temperature 20-40℃, and rinsing time 5-15 minutes. The drying process parameters are drying at 80-120℃ for 30-120 minutes, hot air circulation drying, or vacuum drying. The oxygen content of the clean titanium waste is >0.3wt.% and <1.1wt.%.

[0063] Specifically, the hydrogenation temperature in S2 is 350-550℃; the high-energy ball milling speed is 200-500 rpm, and the time is 5-20 h; the sieve mesh size is 350 mesh; the dehydrogenation temperature is 650-750℃, and the dehydrogenation time is 2-6 h; the oxygen content of the pure titanium powder is >0.45wt.% and <1.1wt.%, the hydrogen content is ≤0.5wt.%, the powder particle size is 0-25μm, and D50 <10μm.

[0064] Specifically, the oxygen content of the pure titanium powder in S2 is mainly determined by the oxygen content of the titanium waste itself; if the oxygen content does not meet the required range, TiO2 needs to be added to adjust the oxygen content to the required range.

[0065] Specifically, the pressure applied during S3 molding is 200-450 MPa, and the holding time is 60-350 s.

[0066] Specifically, in S4, at a vacuum degree of 10... -1 -10 -3 Sintering is carried out under Pa conditions, with the sintering temperature controlled between 1100-1200℃ and held for 1-4 hours; the density of the pure titanium sintered billet is >96%, and the average grain size is <30μm.

[0067] Specifically, before hot working deformation in S5, it is necessary to heat to 1100-1250℃ and hold for 1-2 hours; the deformation amount of hot working deformation needs to be controlled at 30-50%; the density of pure titanium products is >99%, the oxygen content is ≥0.5wt.% and ≤1.1wt.%, and the average grain size is ≤40μm.

[0068] Specifically, the temperature for the heating and heat preservation treatment in S6 is 860-960℃, and the heat preservation time is 1-10min; the deformation amount is controlled at 5-15% each time; the oxygen content of the pure titanium product in one cycle is ≥0.5wt.% and ≤1.1wt.%, and the average grain size is ≤20μm.

[0069] Specifically, the number of cycles in S7 is determined by the oxygen content of pure titanium. Once the oxygen content is >0.9wt.%, the number of cycles is ≥6, and the prepared pure titanium material has a density >99.9%, tensile strength ≥900MPa, yield strength ≥750MPa, yield ratio ≥0.81, elongation ≥11%, and strength-ductility product ≥10GPa.

[0070] In particular, the methods described in S1-S7 are not limited to the recycling of pure titanium waste, but are also applicable to the recycling of other α and α+β series titanium alloy waste.

[0071] Example 1

[0072] This embodiment presents a technique for preparing ultra-high strength and toughness pure titanium materials based on titanium waste. The technique combines... Figure 1 The specific steps are as follows:

[0073] S1. Titanium Waste Processing: Commercially available pure titanium waste is automatically conveyed into an ultrasonic cleaner for ultrasonic cleaning at 70℃ using water as the cleaning medium at 40kHz for 80 minutes. After ultrasonic cleaning, the pure titanium waste is automatically transferred to a clean water tank for secondary rinsing. The secondary rinsing process parameters are: deionized water rinsing, rinsing temperature 30℃, and rinsing time 10 minutes. It is then transferred to a drying system for drying, with the drying process parameters being: 100℃, 60 minutes, and hot air circulation drying. Finally, a clean surface pure titanium waste is obtained. The oxygen content of the clean surface pure titanium waste is 0.75 wt.%.

[0074] S2. Hydrogenation and Dehydrogenation Treatment: The clean titanium waste obtained in step S1 is fed into a hydrogenation-dehydrogenation device for hydrogenation at a temperature of 420℃. The hydrogenation process ends when the hydrogen absorption is controlled at 3.8 wt.%. The resulting hydrogenated material is thoroughly crushed by a high-energy ball mill with a ball-to-material ratio of 12:1, a rotation speed of 350 rpm, and a time of 18 hours. After screening, the sieve mesh size is 350 mesh, the dehydrogenation temperature is 680℃, and the dehydrogenation time is 4 hours to obtain pure titanium powder. The pure titanium powder has an oxygen content of 0.8 wt.%, a hydrogen content ≤0.5 wt.%, a particle size of 0-25 μm, and a D50 <10 μm.

[0075] S3. Cold isostatic pressing: The pure titanium powder obtained in step S2 is placed into a cold isostatic pressing sleeve, and after compaction, it is sealed. Then, the powder filling mold is placed in the cold isostatic pressing device for pressing. The pressing pressure is 200MPa and the holding time is 90s. After pressing, the mold is demolded to obtain a pure titanium compact.

[0076] S4. Vacuum sintering: The pure titanium compact obtained in step S3 is placed in a vacuum sintering furnace and sintered under a vacuum of 10... -2 Sintering was carried out under Pa conditions, with the sintering temperature controlled at 1180℃ and held for 2 hours. After sintering, the furnace was cooled to room temperature to obtain pure titanium sintered billets. The density of the pure titanium sintered billets was about 99%, and the average grain size was about 26μm.

[0077] S5. Hot working deformation: The pure titanium sintered billet obtained in step S4 is placed in a resistance heating furnace and heated to 1150℃ for 2 hours. After the heating is completed, the sample is taken out and hot-deformed by forging. The deformation amount of hot working deformation needs to be controlled within 40% to obtain pure titanium products. The density of the pure titanium products is 99.2%, the oxygen content is about 0.82 wt.%, and the average grain size is about 20 μm.

[0078] S6. First α-hot deformation treatment: The pure titanium product obtained in step S5 is heated and held at a temperature of 920℃ for 6 minutes; then, it is hot-deformed by forging, with the deformation amount controlled at 10% per cycle to obtain a pure titanium product in one cycle; the oxygen content of the pure titanium product in one cycle is about 0.82 wt.%, and the average grain size is less than 18 μm;

[0079] S7. Cyclic α-heat deformation treatment: The pure titanium product obtained from one cycle in S6 is subjected to multiple cycles of thermomechanical treatment. The thermomechanical treatment process is the same as that in S6, with 6 cycles, to obtain pure titanium material that has been cycled multiple times.

[0080] The ultra-high strength and toughness pure titanium material prepared by recycling titanium waste in this embodiment has an oxygen content of about 0.82 wt.%, a density of >99.9%, a tensile strength of >1000 MPa, a yield strength of >850 MPa, a yield strength ratio of >0.85, an elongation of >11%, and a strength-ductility product of >11 GPa%. It has a uniform microstructure, a dense structure, and fine grains.

[0081] Example 2

[0082] This embodiment presents a technique for preparing ultra-high strength and toughness pure titanium materials based on titanium waste. The technique combines... Figure 1 The specific steps are as follows:

[0083] S1. Titanium Waste Processing: Commercially available pure titanium waste is automatically conveyed into an ultrasonic cleaner for ultrasonic cleaning at 60°C using water as the cleaning medium at 45kHz for 90 minutes. After ultrasonic cleaning, the pure titanium waste is automatically transferred to a clean water tank for a second rinse. The second rinsing process parameters are: deionized water rinsing, rinsing temperature 25°C, and rinsing time 12 minutes. It is then transferred to a drying system for drying, with the drying process parameters being 90°C, 80 minutes, and hot air circulation drying. Finally, a clean surface pure titanium waste is obtained. The oxygen content of the clean surface pure titanium waste is 0.95 wt.%.

[0084] S2. Hydrogenation and Dehydrogenation Treatment: The clean titanium waste obtained in step S1 is fed into a hydrogenation-dehydrogenation device for hydrogenation at a temperature of 400℃. The hydrogenation process ends when the hydrogen absorption is controlled at 3.2 wt.%. The resulting hydrogenated material is thoroughly crushed by a high-energy ball mill with a ball-to-material ratio of 10:1, a rotation speed of 400 rpm, and a time of 12 hours. After screening, the sieve mesh size is 350 mesh, the dehydrogenation temperature is 720℃, and the dehydrogenation time is 3 hours to obtain pure titanium powder. The pure titanium powder has an oxygen content of 1.0 wt.%, a hydrogen content ≤0.5 wt.%, a particle size of 0-25 μm, and a D50 <10 μm.

[0085] S3. Cold isostatic pressing: The pure titanium powder obtained in step S2 is placed into a cold isostatic pressing sleeve, and after compaction, it is sealed. Then, the powder mold is placed in the cold isostatic pressing device for pressing. The pressing pressure is 400MPa and the holding time is 100s. After pressing, the mold is demolded to obtain a pure titanium compact.

[0086] S4. Vacuum sintering: The pure titanium compact obtained in step S3 is placed in a vacuum sintering furnace and sintered under a vacuum of 10... -3 Sintering was carried out under Pa conditions, with the sintering temperature controlled at 1200℃ and held for 3 hours. After sintering, the furnace was cooled to room temperature to obtain pure titanium sintered billets. The density of the pure titanium sintered billets was about 99.5%, and the average grain size was about 28.5 μm.

[0087] S5. Hot working deformation: The pure titanium sintered billet obtained in step S4 is placed in a resistance heating furnace and heated and held at 1180℃ for 1.5 hours. After the holding period, the sample is taken out and hot-deformed by forging. The deformation amount of hot working deformation needs to be controlled within 50% to obtain pure titanium products. The density of the pure titanium products is about 99.4%, the oxygen content is about 1.0 wt.%, and the average grain size is about 20 μm.

[0088] S6. First α-hot deformation treatment: The pure titanium product obtained in step S5 is heated and held at a temperature of 955℃ for 5 minutes; then, it is hot-deformed by forging, with the deformation amount controlled at 8% per cycle to obtain a pure titanium product for one cycle; the oxygen content of the pure titanium product for one cycle is about 1.0 wt.%, and the average grain size is less than 18 μm;

[0089] S7. Cyclic α-heat deformation treatment: The pure titanium product obtained from one cycle in S6 is subjected to multiple cycles of thermomechanical treatment. The thermomechanical treatment process is the same as that in S6, with 7 cycles, to obtain pure titanium material that has been cyclically processed.

[0090] The ultra-high strength and toughness pure titanium material prepared by recycling titanium waste in this embodiment has an oxygen content of about 1.0 wt.%, a density of 99.99%, a tensile strength greater than 1120 MPa, a yield strength greater than 950 MPa, a yield ratio greater than 0.84, an elongation greater than 11%, and a strength-ductility product greater than 12 GPa%. It has a uniform microstructure, a dense structure, and fine grains.

[0091] Example 3

[0092] This embodiment presents a technique for preparing ultra-high strength and toughness pure titanium materials based on titanium waste. The technique combines... Figure 1 The specific steps are as follows:

[0093] S1. Titanium Waste Processing: Commercially available pure titanium waste is automatically conveyed into an ultrasonic cleaner for ultrasonic cleaning at 90°C using water as the cleaning medium at 35 kHz for 60 minutes. After ultrasonic cleaning, the pure titanium waste is automatically transferred to a clean water tank for secondary rinsing. The secondary rinsing process parameters are: deionized water rinsing, rinsing temperature 40°C, and rinsing time 8 minutes. Subsequently, it is transferred to a drying system for drying. The drying process parameters are: 110°C, 45 minutes, and vacuum drying. Finally, a clean surface pure titanium waste is obtained. The oxygen content of the clean surface pure titanium waste is 0.60 wt.%.

[0094] S2. Hydrogenation and Dehydrogenation Treatment: The clean titanium waste obtained in step S1 is fed into a hydrogenation-dehydrogenation device for hydrogenation at a temperature of 380℃. The hydrogenation process ends when the hydrogen absorption is controlled at 3.6 wt.%. The resulting hydrogenated material is thoroughly crushed by a high-energy ball mill with a ball-to-material ratio of 8:1, a rotation speed of 280 rpm, and a time of 8 hours. After screening, the sieve mesh size is 350 mesh, the dehydrogenation temperature is 650℃, and the dehydrogenation time is 6 hours to obtain pure titanium powder. The pure titanium powder has an oxygen content of 0.65 wt.%, a hydrogen content ≤0.5 wt.%, a particle size of 0-25 μm, and a D50 <10 μm.

[0095] S3. Cold isostatic pressing: The pure titanium powder obtained in step S2 is placed into a cold isostatic pressing sleeve, and after compaction, it is sealed. Then, the powder filling mold is placed in the cold isostatic pressing device for pressing. The pressing pressure is 350MPa and the holding time is 150s. After pressing, the mold is demolded to obtain a pure titanium compact.

[0096] S4. Vacuum sintering: The pure titanium compact obtained in step S3 is placed in a vacuum sintering furnace and sintered under a vacuum of 10... -2Sintering was carried out under Pa conditions, with the sintering temperature controlled at 1100℃ and held for 4 hours. After sintering, the furnace was cooled to room temperature to obtain pure titanium sintered billets. The density of the pure titanium sintered billets was about 96.7%, and the average grain size was about 18μm.

[0097] S5. Hot working deformation: The pure titanium sintered billet obtained in step S4 is placed in a resistance heating furnace and heated to 1120℃ for 1.5 hours. After the heating is completed, the sample is taken out and hot-deformed by forging. The deformation amount of hot working deformation needs to be controlled within 30% to obtain pure titanium products. The density of the pure titanium products is about 99.1%, the oxygen content is about 0.7 wt.%, and the average grain size is about 14 μm.

[0098] S6. First α-hot deformation treatment: The pure titanium product obtained in step S5 is heated and held at a temperature of 900℃ for 9 minutes; then hot deformation is carried out by extrusion, with the deformation amount controlled at 15% per cycle to obtain a pure titanium product in one cycle; the oxygen content of the pure titanium product in one cycle is about 0.7 wt.%, and the average grain size is less than 12 μm;

[0099] S7. Cyclic α-heat deformation treatment: The pure titanium product obtained from one cycle in S6 is subjected to multiple cycles of thermomechanical treatment. The thermomechanical treatment process is the same as that in S6, with 5 cycles, to obtain pure titanium material that has been cyclically processed.

[0100] The ultra-high strength and toughness pure titanium material prepared by recycling titanium waste in this embodiment has an oxygen content of about 0.7 wt.%, a density of 99.99%, a tensile strength greater than 900 MPa, a yield strength greater than 780 MPa, a yield ratio greater than 0.83, an elongation greater than 13%, and a strength-ductility product greater than 11.5 GPa%. Its microstructure is uniform, its structure is dense, and its grains are fine.

[0101] Example 4

[0102] This embodiment presents a technique for preparing ultra-high strength and toughness pure titanium materials based on titanium waste. The technique combines... Figure 1 The specific steps are as follows:

[0103] S1. Titanium Waste Processing: Commercially available pure titanium waste is automatically conveyed into an ultrasonic cleaner for ultrasonic cleaning at 90℃ using water as the cleaning medium at 30kHz for 70 minutes. After ultrasonic cleaning, the pure titanium waste is automatically transferred to a clean water tank for secondary rinsing. The secondary rinsing process parameters are: deionized water rinsing, rinsing temperature 30℃, and rinsing time 8 minutes. It is then transferred to a drying system for drying. The drying process parameters are: 100℃, 50 minutes, and vacuum drying. Finally, a clean surface pure titanium waste is obtained. The oxygen content of the clean surface pure titanium waste is 0.78 wt.%.

[0104] S2. Hydrogenation and Dehydrogenation Treatment: The clean titanium waste obtained in step S1 is fed into a hydrogenation-dehydrogenation device for hydrogenation at a temperature of 450℃. The hydrogenation process ends when the hydrogen absorption is controlled at 3.7 wt.%. The resulting hydrogenated material is thoroughly crushed by a high-energy ball mill with a ball-to-material ratio of 8:1, a rotation speed of 360 rpm, and a time of 10 hours. After screening, the sieve mesh size is 350 mesh, the dehydrogenation temperature is 700℃, and the dehydrogenation time is 4 hours to obtain pure titanium powder. The pure titanium powder has an oxygen content of 0.85 wt.%, a hydrogen content ≤0.5 wt.%, a particle size of 0-25 μm, and a D50 <10 μm.

[0105] S3. Cold isostatic pressing: The pure titanium powder obtained in step S2 is placed into a cold isostatic pressing sleeve, and after compaction, it is sealed. Then, the powder filling mold is placed in the cold isostatic pressing device for pressing. The pressing pressure is 300MPa and the holding time is 120s. After pressing, the mold is demolded to obtain a pure titanium compact.

[0106] S4. Vacuum sintering: The pure titanium compact obtained in step S3 is placed in a vacuum sintering furnace and sintered under a vacuum of 10... -2 Sintering was carried out under Pa conditions, with the sintering temperature controlled at 1160℃ and held for 3 hours. After sintering, the furnace was cooled to room temperature to obtain pure titanium sintered billets. The density of the pure titanium sintered billets was about 98.5%, and the average grain size was about 24 μm.

[0107] S5. Hot working deformation: The pure titanium sintered billet obtained in step S4 is placed in a resistance heating furnace and heated to 1160℃ for 1.5 hours. After the heating is completed, the sample is taken out and hot-deformed by forging. The deformation amount of hot working deformation is controlled at 45% to obtain pure titanium products. The density of the pure titanium products is about 99.5%, the oxygen content is about 0.90 wt.%, and the average grain size is about 16.5 μm.

[0108] S6. First α-hot deformation treatment: The pure titanium product obtained in step S5 is heated and held at a temperature of 940℃ for 6 minutes; then, it is hot-deformed by forging, with the deformation amount controlled at 10% per cycle to obtain a pure titanium product for one cycle; the oxygen content of the pure titanium product for one cycle is about 0.90 wt.%, and the average grain size is less than 13 μm;

[0109] S7. Cyclic α-heat deformation treatment: The pure titanium product obtained from one cycle in S6 is subjected to multiple cycles of thermomechanical treatment. The thermomechanical treatment process is the same as that in S6, with 6 cycles, to obtain pure titanium material that has been cycled multiple times.

[0110] The ultra-high strength and toughness pure titanium material prepared by recycling titanium waste in this embodiment has an oxygen content of about 0.90 wt.%, a density of 99.99%, a tensile strength greater than 1050 MPa, a yield strength greater than 900 MPa, a yield ratio greater than 0.85, an elongation greater than 12%, and a strength-ductility product greater than 12 GPa%. It has a uniform microstructure, a dense structure, and fine grains.

[0111] Example 5

[0112] This embodiment presents a technique for preparing ultra-high strength and toughness titanium alloy materials based on titanium waste. The alloy material is TC4 titanium alloy. The technique for preparing ultra-high strength and toughness titanium alloy materials based on titanium waste is combined with… Figure 1 The specific steps are as follows:

[0113] S1. Titanium Waste Processing: Commercially available TC4 waste is automatically conveyed into an ultrasonic cleaner for ultrasonic cleaning at 38 kHz for 60 minutes using water as the cleaning medium at 70°C. After ultrasonic cleaning, the pure titanium waste is automatically transferred to a clean water tank for a second rinse. The second rinsing parameters are: deionized water rinsing, rinsing temperature 40°C, and rinsing time 10 minutes. It is then transferred to a drying system for drying, with the drying parameters being: 80°C, 60 minutes, and hot air circulation drying. Finally, a clean TC4 waste is obtained with an oxygen content of 0.35 wt.%.

[0114] S2. Hydrogenation and Dehydrogenation Treatment: The clean TC4 waste obtained in step S1 is fed into a hydrogenation-dehydrogenation device for hydrogenation at a temperature of 400℃. The hydrogenation process ends when the hydrogen absorption is controlled at 3.8 wt.%. The resulting hydrogenated material is thoroughly crushed by a high-energy ball mill with a ball-to-material ratio of 10:1, a rotation speed of 400 rpm, and a time of 15 hours. After screening, the sieve mesh size is 350 mesh, the dehydrogenation temperature is 730℃, and the dehydrogenation time is 3 hours to obtain TC4 titanium alloy powder. The oxygen content of the TC4 titanium alloy powder is 0.42 wt.%, the hydrogen content is ≤0.5 wt.%, the powder particle size is 0-25 μm, and D50 <10 μm.

[0115] S3. Cold isostatic pressing: The TC4 titanium alloy powder obtained in step S2 is placed into a cold isostatic pressing sleeve, and after compaction, it is sealed. Then, the powder loading mold is placed in the cold isostatic pressing device for pressing. The pressing pressure is 350MPa and the holding time is 200s. After pressing, the mold is demolded to obtain a pure titanium blank.

[0116] S4. Vacuum Sintering: The TC4 titanium alloy compact obtained in step S3 is placed in a vacuum sintering furnace and sintered under a vacuum of 10... - 1 Sintering was carried out under Pa conditions, with the sintering temperature controlled at 1150℃ and held for 4 hours. After sintering, the sintered billet was cooled to room temperature in the furnace to obtain TC4 titanium alloy sintered billet. The density of TC4 titanium alloy sintered billet was about 98.2%, and the average grain size was about 22 μm.

[0117] S5. Hot working deformation: The pure titanium sintered billet obtained in step S4 is placed in a resistance heating furnace and heated to 1150℃ for 1.5 hours. After the heating is completed, the sample is taken out and hot-deformed by rolling. The deformation amount of hot working deformation is controlled at 45%, thereby obtaining TC4 titanium alloy products. The density of TC4 titanium alloy products is about 99.6%, the oxygen content is about 0.50 wt.%, and the average grain size is about 15 μm.

[0118] S6. First α-hot deformation treatment: The TC4 titanium alloy product obtained in step S5 is heated and held at 920℃ for 10 minutes; then, it is hot-deformed by forging, with the deformation amount controlled at 15% per cycle to obtain a TC4 titanium alloy product in one cycle; the oxygen content of the TC4 titanium alloy product in one cycle is about 0.50 wt.%, and the average grain size is less than 10 μm;

[0119] S7. Cyclic α-Hot Deformation Treatment: The TC4 titanium alloy product obtained from one cycle in S6 is subjected to multiple cycles of thermomechanical treatment. The thermomechanical treatment process is the same as that in S6, with 3 cycles, to obtain TC4 titanium alloy material that has undergone multiple cycles.

[0120] The ultra-high strength and toughness TC4 titanium alloy material prepared by recycling titanium waste in this embodiment has an oxygen content of about 0.50 wt.%, a density of 99.99%, a tensile strength greater than 1250 MPa, a yield strength greater than 1100 MPa, a yield-to-tensile ratio greater than 0.86, an elongation greater than 12%, and a strength-ductility product greater than 15 GPa%. It has a uniform microstructure, a dense structure, and fine grains.

[0121] The above-described solution proposes a technology for preparing ultra-high strength and toughness pure titanium materials from titanium waste. This technology effectively solves the problem that during the recycling of titanium and titanium alloy waste, the high oxygen content leads to a significant decrease in material plasticity, easy brittle fracture, and difficulty in direct recycling. Existing recycling methods typically reduce oxygen content by mixing and diluting with a large amount of low-oxygen titanium, or by adding elements such as Ca, Mg, and Re under high-temperature conditions to carry out an oxygen fixation reaction. However, these methods suffer from technical problems such as complex processes, high costs, low recovery rates, and unstable performance of the resulting products.

[0122] Unlike existing complex processes that involve diluting with large amounts of low-oxygen titanium or using high-temperature oxygen removal with elements such as Ca, Mg, and Re, this invention achieves controllable regulation of the distribution and bonding state of interstitial oxygen in the titanium matrix through a combination of thermomechanical treatment and interstitial element control. This fundamentally weakens the short-range strong coupling between oxygen and dislocations and significantly reduces oxygen embrittlement sensitivity.

[0123] This method does not require the addition of high-cost alloying elements such as Al, V, Mo, Zr, Cr, and Ta, nor does it require a deep deoxidation process. It can fully utilize the interstitial oxygen strengthening effect inherent in titanium waste, thereby achieving ultra-high strength while maintaining good plasticity.

[0124] The high-oxygen pure titanium prepared by the method of this invention has a tensile strength of over 900 MPa and an elongation of not less than 11%. It achieves a synergistic improvement in strength and plasticity under non-alloying conditions, breaking through the inherent limitation of traditional high-oxygen titanium materials that "strength improvement is accompanied by loss of plasticity".

[0125] The process of this invention is simple, energy-efficient, and low-cost. It does not require acid-base chemical deoxidation and the production process is clean and environmentally friendly. It has significant potential for industrial application and promotion value, and provides a green, low-carbon, and sustainable new technology path for the high-value regeneration of high-oxygen titanium waste.

[0126] This invention is not limited to the recycling of pure titanium, but is also applicable to the recycling and utilization of other α and α+β series titanium alloy wastes such as Ti-6Al-4V, Ti-6Al, Ti-5Al-2.5Sn and Ti-6Al-2Sn-4Zr-2Mo.

[0127] This invention, through the process concept of "oxygen preservation-regulation-utilization", transforms interstitial oxygen, which was originally considered a detrimental factor, into a usable enhanced resource, thereby achieving high-value recycling and efficient resource recycling of pure titanium waste, which is in line with the development trend of low-carbon, energy-saving and green manufacturing.

[0128] In summary, compared with traditional methods, the proposed pure titanium waste treatment process combines high-temperature hot deformation technology with multi-stage cyclic thermomechanical treatment in the α-phase region, achieving the preparation of ultra-high strength and toughness pure titanium materials. Furthermore, by subjecting pure titanium to multiple cyclic α-hot deformation treatments under high oxygen conditions, the interstitial oxygen in the pure titanium matrix can be controlled and adjusted, significantly expanding the tolerance range of pure titanium materials to oxygen content. Without the need to add any alloying strengthening elements or perform costly deep deoxidation treatment, this invention can obtain pure titanium materials with both high strength and high plasticity. The method is flexible, easy to operate, and widely applicable, making it suitable for low-cost, high-efficiency industrial recycling and large-scale production of pure titanium waste.

[0129] It should be understood that the term "and / or" in this article is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. A and B can be singular or plural. Additionally, the character " / " in this article generally indicates an "or" relationship between the preceding and following related objects, but it can also represent an "and / or" relationship. Please refer to the context for a more accurate understanding.

[0130] In this invention, "at least one" means one or more, and "more than one" means two or more. "At least one of the following" or similar expressions refer to any combination of these items, including any combination of a single item or a plurality of items. For example, at least one of a, b, or c can represent: a, b, c, ab, ac, bc, or abc, where a, b, and c can be a single item or multiple items.

[0131] It should be understood that, in various embodiments of the present invention, the order of the above-mentioned process numbers does not imply the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present invention.

[0132] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A technology for preparing ultra-high strength and toughness pure titanium materials based on titanium waste, characterized in that, The specific steps of the technology for preparing ultra-high strength and toughness pure titanium materials based on titanium waste are as follows: S1. Titanium waste treatment: Commercially available pure titanium waste is automatically conveyed into an ultrasonic cleaner for ultrasonic cleaning; after cleaning, the waste is automatically transported to a clean water tank for secondary rinsing, and then enters a drying device for drying, finally obtaining pure titanium waste with a clean surface. S2, Hydrogenation and Dehydrogenation Treatment: The clean titanium waste obtained in step S1 is fed into a hydrogenation-dehydrogenation equipment for hydrogenation. The hydrogenation process ends when the hydrogen absorption is controlled between 3.0-4.0 wt.%. The resulting hydrogenated material is fully crushed by high-energy ball milling and then dehydrogenated after sieving to obtain pure titanium powder. S3. Cold isostatic pressing: The pure titanium powder obtained in step S2 is placed into a cold isostatic pressing sleeve, and after compaction, it is sealed. Then, the powder filling mold is placed in the cold isostatic pressing device for pressing and forming. After pressing, the mold is demolded to obtain a pure titanium compact. S4. Vacuum sintering: The pure titanium billet obtained in step S3 is placed in a vacuum sintering furnace and sintered under vacuum conditions. After sintering, it is cooled to room temperature with the furnace to obtain a pure titanium sintered billet. S5. Hot working deformation: The pure titanium sintered billet obtained in step S4 is placed in a resistance heating furnace for heating and holding. After the holding period, the sample is taken out and hot deformation processing is carried out by forging, extrusion or rolling to obtain pure titanium products. S6. First α hot deformation treatment: The pure titanium product obtained in step S5 is heated and kept at a constant temperature, and then hot deformation processing is carried out by forging, extrusion or rolling to obtain a pure titanium product in one cycle. S7. Cyclic α-thermal deformation treatment: The pure titanium product obtained from one cycle in S6 is subjected to multiple cycles of thermomechanical treatment. The thermomechanical treatment process is the same as that in S6, resulting in pure titanium material that has undergone multiple cycles.

2. The technology for preparing ultra-high strength and toughness pure titanium materials based on titanium waste according to claim 1, characterized in that, In S1, ultrasonic cleaning is performed at 20-50 kHz for 20-100 min using water as the cleaning medium at 50-90℃. The oil and impurities on the surface of the titanium waste are fully decomposed and removed through segmented cleaning. The process parameters for the secondary rinsing are deionized water rinsing, rinsing temperature 20-40℃, and rinsing time 5-15 min. The drying process parameters are drying at 80-120℃ for 30-120 min, hot air circulation drying, or vacuum drying. The oxygen content of the clean titanium waste is >0.3 wt.% and <1.1 wt.%.

3. The technology for preparing ultra-high strength and toughness pure titanium materials based on titanium waste according to claim 1, characterized in that, The hydrogenation temperature in S2 is 350-550℃; the high-energy ball milling speed is 200-500 rpm, and the time is 5-20 h; the sieve mesh size is 350 mesh; the dehydrogenation temperature is 650-750℃, and the dehydrogenation time is 2-6 h; the oxygen content of the pure titanium powder is >0.45wt.% and <1.1wt.%, the hydrogen content is ≤0.5wt.%, the powder particle size is 0-25μm, and D50 <10μm.

4. The technology for preparing ultra-high strength and toughness pure titanium materials based on titanium waste according to claim 1, characterized in that, The oxygen content of pure titanium powder in S2 is mainly determined by the oxygen content of the titanium waste itself; if the oxygen content does not meet the required range, TiO2 needs to be added to adjust the oxygen content to the required range.

5. The technology for preparing ultra-high strength and toughness pure titanium materials based on titanium waste according to claim 1, characterized in that, The pressure applied during S3 molding is 200-450 MPa, and the holding time is 60-350 s.

6. The technology for preparing ultra-high strength and toughness pure titanium materials based on titanium waste according to claim 1, characterized in that, In S4, the vacuum degree is 10 -1 -10 -3 Sintering is carried out under Pa conditions, with the sintering temperature controlled between 1100-1200℃ and held for 1-4 hours; the density of the pure titanium sintered billet is >96%, and the average grain size is <30μm.

7. The technology for preparing ultra-high strength and toughness pure titanium materials based on titanium waste according to claim 1, characterized in that, Before hot working deformation in S5, it needs to be heated to 1100-1250℃ and held for 1-2 hours; the deformation amount of hot working deformation needs to be controlled within 30-50%; the density of pure titanium products is >99%, the oxygen content is ≥0.5wt.% and ≤1.1wt.%, and the average grain size is ≤40μm.

8. The technology for preparing ultra-high strength and toughness pure titanium materials based on titanium waste according to claim 1, characterized in that, The heating and heat preservation temperature in S6 is 860-960℃, and the heat preservation time is 1-10min; the deformation amount is controlled at 5-15% each time; the oxygen content of pure titanium products in one cycle is ≥0.5wt.% and ≤1.1wt.%, and the average grain size is ≤20μm.

9. The technology for preparing ultra-high strength and toughness pure titanium materials based on titanium waste according to claim 1, characterized in that, The number of cycles in S7 is determined by the oxygen content of pure titanium. Once the oxygen content is >0.9wt.%, the number of cycles is ≥6, and the prepared pure titanium material has a density >99.9%, tensile strength ≥900MPa, yield strength ≥750MPa, yield ratio ≥0.81, elongation ≥11%, and strength-ductility product ≥10GPa.

10. The technology for preparing ultra-high strength and toughness pure titanium materials based on titanium waste according to claim 1, characterized in that, The methods described in S1-S7 are not limited to the recycling of pure titanium waste, but are also applicable to the recycling of other α and α+β series titanium alloy waste.

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