Titanium alloy with enhanced foreign object damage resistance and preparation method thereof

Abstract

The invention belongs to the technical field of titanium alloy preparation, and particularly discloses a foreign object damage resistance enhanced titanium alloy and a preparation method thereof.The foreign object damage resistance enhanced titanium alloy is prepared from, by mass, 4.5%-5.0% of Al, 5.5%-7.0% of the total amount of Mo and Cr, 5.0%-7.0% of the total amount of Sn and Zr and the balance Ti; titanium powder and the intermediate alloy powder are mixed to obtain mixed powder; performing cold isostatic pressing on the mixed powder to obtain a green body, and performing vacuum sintering on the green body to obtain a sintered ingot; the sintered ingot is subjected to hot isostatic pressing treatment, and a hot isostatic pressing ingot is obtained; the hot isostatic pressing ingot is pre-forged, and a powder metallurgy forged sample is obtained; and the powder metallurgy forged sample is subjected to heat treatment, and the titanium alloy component is obtained. According to the method, the alloy components are adjusted, the content of beta stable elements is optimized, and the dynamic impact performance and damage tolerance of the titanium alloy material are improved.

Description

Technical Field

[0001] This invention belongs to the field of titanium alloy preparation technology, and more specifically, relates to a titanium alloy with enhanced resistance to foreign object damage and its preparation method. Background Technology

[0002] High-strength and high-toughness titanium alloys are widely used in critical components of aero-engines, such as compressor disks and blades. These alloys possess excellent high strength, high toughness, good fatigue performance, and good high-temperature resistance, making them the preferred material for critical aero-engine components. However, during high-speed rotation, these critical components may ingest micron-sized hard debris and birds from the air, leading to impact pits, microcracks, and other foreign object damage on the surface. Foreign object impact loads not only directly affect the performance of components but can also become the source of fatigue cracks, ultimately causing premature failure of engine components and seriously threatening the safety and reliability of the engine.

[0003] Currently, research on improving the resistance of titanium alloys to foreign object damage mainly focuses on two directions: one is to enhance the surface resistance to foreign object damage through surface strengthening treatments such as shot peening and laser shock peening; the other is to improve the toughness of the material by controlling the microstructure to obtain a bimodal or basketweave structure through heat treatment. However, the depth of surface strengthening treatment layers is limited and may fail under repeated impacts; while microstructure control usually relies on adjusting the alloy composition, but the improvement effect is limited.

[0004] Therefore, there is an urgent need for a method to prepare titanium alloys that can improve the dynamic impact performance of titanium alloys, significantly enhance their resistance to foreign object damage, and at the same time not affect other basic properties. Summary of the Invention

[0005] In view of the above-mentioned defects or improvement needs of the prior art, the present invention provides a titanium alloy with enhanced resistance to foreign object damage and a method for preparing the same, the purpose of which is to improve the resistance of titanium alloy to foreign object damage.

[0006] To achieve the above objectives, according to one aspect of the present invention, a method for preparing a titanium alloy with enhanced resistance to foreign object damage is provided, comprising the following steps: S1. Based on the following mass fractions: Al 4.5%~5.0%, total Mo and Cr 5.5%~7.0%, total Sn and Zr 5.0%~7.0%, with the balance being Ti; titanium powder and intermediate alloy powder are mixed to obtain a mixed powder; S2. The mixed powder is cold isostatically pressed into a green blank, and the green blank is vacuum sintered to obtain a sintered ingot. S3. The sintered ingot is subjected to hot isostatic pressing to obtain a hot isostatic pressed ingot. S4. Pre-forge the hot isostatic pressed ingot to obtain powder metallurgy forged samples; S5. Heat-treat the powder metallurgy forged sample to obtain a titanium alloy component.

[0007] As a further preferred embodiment, in step S2, the cold isostatic pressure is 100MPa to 300MPa, and the holding time is 30min to 120min.

[0008] As a further preferred option, in step S2, the sintering temperature is 1300℃~1400℃ and the time is 2h~6h.

[0009] As a further preferred embodiment, in step S3, the hot isostatic pressing temperature is 850℃~1000℃, the pressure is 100MPa~300MPa, and the holding time is 30min~240min.

[0010] As a further preferred option, in step S4, the pre-forging temperature is 10℃ to 60℃ below the phase transformation point, and the holding time is 60min to 240min.

[0011] As a further preferred option, in step S5, the heat treatment adopts a solution-aging process.

[0012] As a further preferred embodiment, step S5, the heat treatment process specifically includes: solution treatment temperature of 30℃~80℃ below the phase transformation point, holding time of 2h~4h, and water quenching; aging treatment temperature of 400℃~700℃, holding time of 4h~10h, and air cooling to room temperature.

[0013] As a further preferred embodiment, the oxygen content of the titanium powder is not greater than 0.15%, the oxygen content of the intermediate alloy powder is not greater than 0.12%, and the mixing time in step S1 is 1h to 24h.

[0014] As a further preferred option, the titanium powder is mixed with the intermediate alloy powder according to the following mass fractions: Al 4.5%~5.0%, Cr 3.0%~3.5%, Mo 2.5%~3.5%, Sn 2.5%~3.5%, Zr 2.5%~3.0%, with the balance being Ti;

[0015] According to another aspect of the present invention, a titanium alloy with enhanced resistance to foreign object damage is provided, which is prepared by the above-described method for preparing a titanium alloy with enhanced resistance to foreign object damage.

[0016] In summary, compared with the prior art, the above-described technical solutions conceived by this invention mainly possess the following technical advantages: 1. This invention adjusts the alloy composition by optimizing the content of β-stabilizing elements, reducing the proportion of Mo and Cr, and appropriately increasing the proportion of Sn and Zr. This achieves a balance between "solid solution homogeneity, precipitation kinetics, and grain boundary behavior," ensuring that α phase preferentially nucleates and disperses within the grains during subsequent processing, rather than forming a continuous α phase at the grain boundaries. Specifically, through powder metallurgy, hot isostatic pressing, and forging, combined with composition optimization, a fine-grained structure and a low segregation tendency are achieved. The comprehensive control of element optimization and heat treatment suppresses the precipitation of continuous grain boundary α phase, making it difficult for cracks to propagate along the grain boundaries. The refined grains significantly increase the number of grain boundaries, and the uniform α / β interface continuously deflects / branchs / passivates the crack propagation process, thereby significantly improving the material's impact resistance and damage tolerance without affecting other basic properties of the alloy.

[0017] 2. This invention ensures complete densification of the ingot and promotes the solid solution diffusion of refractory elements through prolonged vacuum sintering and hot isostatic pressing processes. Simultaneously, it suppresses abnormal β grain growth within a suitable β stability window (850℃~1000℃). Subphase transformation point pre-forging further refines the β grains, disperses and homogenizes the α phase, and reduces microstructural anisotropy. Subsequently, under solution aging heat treatment, a structure of "fine β grains + discontinuous grain boundaries α + uniform α" is formed. p +Fine α s The organization further enhances the alloy's resistance to damage from foreign objects. Attached Figure Description

[0018] Figure 1 This is a microstructure diagram of a titanium alloy with high resistance to foreign object damage according to an embodiment of the present invention; Figure 2 This is a schematic diagram of the free surface velocity of a titanium alloy with high resistance to foreign object damage according to an embodiment of the present invention; Figure 3 This is the microstructure of the titanium alloy after high-speed impact loading according to an embodiment of the present invention. Detailed Implementation

[0019] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention. Furthermore, the technical features involved in the various embodiments of this invention described below can be combined with each other as long as they do not conflict with each other.

[0020] The present invention provides a method for preparing a titanium alloy with enhanced resistance to foreign object damage, comprising the following steps: S1. Based on the following mass fractions: Al 4.5%~5.0%, total Mo+Cr 5.5%~7.0%, total Sn+Zr 5.0%~7.0%, and the balance being Ti; titanium powder is mixed with intermediate alloy powder to obtain a mixed powder.

[0021] Furthermore, the mass fractions of each element in the mixed powder are: Al 4.5%~5.0%, Cr 3.0%~3.5%, Mo 2.5%~3.5%, Sn 2.5%~3.5%, Zr 2.5%~3.0%, with the balance being Ti.

[0022] Specifically, hydrogenated and dehydrogenated titanium powder is used as the main powder, and Al, Mo, Cr, Sn, and Zr intermediate alloy powders are used as auxiliary phases. The intermediate alloy powders are added to the main powder and uniformly mixed. The titanium powder has a particle size D50 of less than 150 μm and an oxygen content of no more than 0.15%, while the intermediate alloy powder has a particle size D50 of less than 100 μm and an oxygen content of no more than 0.12%. The mixed powder contains 0.08%~0.013% O, no more than 0.05% C, no more than 0.05% N, and no more than 0.00125% H. The mixing time is 1 h to 24 h.

[0023] S2. The mixed powder is loaded into a rubber sleeve and pressed into a green blank by cold isostatic pressing; the green blank is vacuum sintered and cooled to obtain a sintered ingot.

[0024] Furthermore, the cold isostatic pressing pressure is 100MPa~300MPa, the holding time is 30min~120min; the sintering temperature is 1300℃~1400℃, and the time is 2h~6h.

[0025] S3. The sintered ingot is subjected to hot isostatic pressing and then cooled to obtain a high-density hot isostatic pressed ingot.

[0026] Furthermore, the hot isostatic pressing temperature is 850℃~1000℃, the pressure is 100MPa~300MPa, and the holding time is 30min~240min.

[0027] S4. The hot isostatic pressing ingot is pre-forged and cooled to obtain a powder metallurgy forged sample.

[0028] Furthermore, the hot isostatically pressed ingot is pre-forged at a temperature 10°C to 60°C below the phase transformation point, with a holding time of 60 min to 240 min.

[0029] S5. Heat-treat the powder metallurgy forged sample to obtain a titanium alloy component.

[0030] Furthermore, the heat treatment employs a solution-aging process; specifically: the solution treatment temperature is the β phase transformation point (T... βThe aging process is carried out at temperatures ranging from 30℃ to 80℃, typically 800℃ to 850℃ for high-strength and high-toughness titanium alloys, with a holding time of 2 to 4 hours. Rapid water quenching is used to retain the supersaturated β phase and metastable phase. The aging treatment temperature is 400℃ to 700℃, with a holding time of 4 to 10 hours, followed by air cooling to room temperature. After solution quenching, a supersaturated metastable β phase is obtained. Aging, through heating, allows these supersaturated elements (mainly aluminum, molybdenum, and chromium) to precipitate from the β matrix as fine, dispersed secondary α phases. These nanoscale precipitates can improve the alloy's strength.

[0031] The composition optimization of this invention does not simply improve strength, but rather controls the stability of the alloy's β phase within a machinable window of "near-β / metastable β," enabling subsequent "metaphase transformation forging + two-stage heat treatment" to stably obtain a fine, uniform, and discontinuous grain boundary α microstructure. To ensure the designed alloy maintains a certain strength, in titanium alloys, an excessively high total Mo+Cr content leads to overly stable β phases (increased β retention, suppressed α precipitation, and increased risk of grain boundary α continuation / coarsening), making it easier to form weakening channels along grain boundaries under dynamic impact compression. Therefore, this invention utilizes the metallurgical properties of Mo: Mo has strong stability in the β phase, inhibiting the diffusion of other elements and exhibiting strong solid solution strengthening ability; Cr has relatively strong stability in the β phase, but its strong diffusion ability easily induces elemental segregation. Sn and Zr, by improving the thermal stability of the microstructure, mainly contribute to solid solution strengthening and reduce the coarsening rate, and can improve dynamic strength and damage tolerance by altering interfacial energy / diffusion behavior, making the α phase finer and more uniformly distributed. By reducing the proportions of Mo and Cr and appropriately increasing the proportions of Sn and Zr, a balance can be achieved between "solid solution homogeneity, precipitation kinetics, and grain boundary behavior." The goal is to allow α to preferentially nucleate and disperse within the grains, rather than forming a continuous α phase at the grain boundaries.

[0032] Material failure following high-speed impact is directly related to the following three points: ① Elemental segregation and agglomeration, coarse grain boundaries, and continuous grain boundary α phase are all sources of porosity initiation; ② Coarse β-phase grain edges (i.e., continuous grain boundary α phase) are the easiest channels for crack propagation; ③ Insufficient interface quantity and deformation capacity cannot passivate, deflect, or bifurcate cracks. This invention, through vacuum sintering and hot isostatic pressing, ensures complete densification of the ingot and promotes the solid solution diffusion of refractory elements, while suppressing abnormal β grain growth within a suitable β stability window; subphase transformation point pre-forging further refines the β grains, disperses and homogenizes the α phase, and reduces microstructural anisotropy; subsequently, under solution aging heat treatment, a structure of "fine β grains + discontinuous grain boundary α + homogenous α" is formed. p + Fine α s "the organization".

[0033] This invention also provides a quantitative characterization method based on a single-stage light gas gun experiment, employing a light gas gun plate impact test to evaluate the alloy's resistance to foreign object damage. Specifically, the material is processed into a target plate, and a copper target fragment is fired from a single-stage light gas gun to impact the target plate. The free surface velocity history is measured using a probe attached to the back of the target plate. The free surface velocity curve "projects" the propagation of the shock wave and the internal damage process of the material, with the key correspondence as follows: Rising / Plate segment: Reflects the wave propagation and plastic response of the material under impact compression, and can directly determine whether there is obvious yielding or plastic wave separation inside the material.

[0034] Rebound characteristics: When the internal tensile stress is large enough and delamination / stripping damage occurs, the free surface velocity will show a significant trough before rebounding. The larger the trough, the stronger the damage event and the more obvious the delamination process. The timing and shape of the rebound can reflect the speed of damage initiation and propagation.

[0035] The following are specific examples: Example 1 Step 1: Using titanium powder as the main powder, Al Mo-Cr-Sn-Zr master alloy powder is used as an auxiliary phase. The master alloy powder is added to the main powder and uniformly mixed for 8 hours. The hydrogenated dehydrogenated titanium powder has a particle size D50 of 75 μm and an oxygen content of 0.09%, while the master alloy powder has a particle size D50 of 35 μm and an oxygen content of 0.10%. The mass percentage of each alloying element in the mixed powder is: Al 5.00%, Cr 3.50%, Mo 2.50%, Sn 2.50%, Zr 2.50%, O 0.12%, C 0.012%, N 0.032%, H 0.00112%, with the balance being Ti. Step 2: The uniformly mixed alloy powder from Step 1 is loaded into a rubber sleeve and pressed into a green compact using a cold isostatic pressing process at a pressure of 300 MPa for 120 minutes; under a vacuum of 10... -4 Under Pa protection, the pressed green billet is vacuum sintered at a high temperature of 1300℃ for 4 hours. After cooling to room temperature, a titanium alloy sintered ingot is obtained. Step 3: The sintered sample obtained in Step 2 is subjected to hot isostatic pressing (HIP). The HIP pressure is 300 MPa, the temperature is 850 °C, and the holding time is 30 min. The HIP process ensures that the sample density reaches 100%, and a titanium alloy HIP sample is obtained.

[0036] Step 4: The hot isostatic pressing sample obtained in Step 3 is forged in one pass at a temperature of 850℃ for 60 minutes to obtain a titanium alloy forging sample.

[0037] Step 5: Heat-treat the forged sample obtained in Step 4 at 800℃ for 2 hours, then furnace cool it to 400℃ and hold it for 10 hours to obtain the final titanium alloy sample.

[0038] Step 6: Process the material into a target plate with a diameter of φ10mm and a thickness of 2mm. Use a first-level light air gun to launch a copper target plate with a diameter of φ25mm×1, impacting the target plate at speeds of 400m / s and 500m / s. Test the free surface velocity history through a probe attached to the back of the target plate.

[0039] Figure 1 The free surface velocity of the powder metallurgy-modified titanium alloy in this embodiment shows that the spalling strength reaches 5.01 GPa after a high-speed impact of 400 m / s and 5.64 GPa after a high-speed impact of 500 m / s, which is higher than the spalling strength of the traditional cast and forged TC17 alloy. Figure 2 The diagram shows the microstructure of the titanium alloy with improved powder metallurgy composition in this embodiment. It can be seen that the titanium alloy with high resistance to foreign object damage has fine β grains and discontinuous distribution of α phase at grain boundaries. The primary α grains in the microstructure are short and fine, and the overall microstructure is uniform. Figure 3 To illustrate the microstructure of the powder metallurgy-modified titanium alloy after high-speed impact loading in this embodiment, from... Figure 3 It can be seen that after high-speed impacts of 400m / s and 500m / s, the main cracks are small and discontinuous, and only a few short cracks are seen on the entire damaged surface.

[0040] Example 2 Step 1: The titanium powder obtained after hydrogenation and dehydrogenation is used as the main powder, with Al... Mo-Cr-Sn-Zr master alloy powder is used as an auxiliary phase. The master alloy powder is added to the main powder and uniformly mixed for 9 hours. The hydrogenated dehydrogenated titanium powder has a particle size D50 of 65 μm and an oxygen content of 0.12%, while the master alloy powder has a particle size D50 of 45 μm and an oxygen content of 0.08%. The mass percentage of each alloying element in the mixed powder is: Al 4.50%, Cr 3.00%, Mo 2.50%, Sn 3.50%, Zr 3.00%, O 0.11%, C 0.015%, N 0.028%, H 0.00105%, with the balance being Ti. Step 2: The uniformly mixed alloy powder from Step 1 is loaded into a rubber sleeve and pressed into a green compact using a cold isostatic pressing process at a pressure of 100 MPa for 30 minutes; under a vacuum of 10... -2 Under Pa protection, the pressed green billet is vacuum sintered at a high temperature of 1400℃ for 2 hours. After cooling to room temperature, a titanium alloy sintered ingot is obtained. Step 3: The sintered sample obtained in Step 2 is subjected to hot isostatic pressing (HIP). The HIP pressure is 100 MPa, the temperature is 100 °C, and the holding time is 240 min. The HIP process ensures that the sample density reaches 100%, thus obtaining a titanium alloy HIP sample.

[0041] Step 4: The hot isostatic pressing sample obtained in Step 3 is forged in one pass at a temperature of 820℃ for 240 minutes to obtain a titanium alloy forging sample.

[0042] Step 5: Heat-treat the forged sample obtained in Step 4 at 850℃ for 4 hours, then furnace cool it to 700℃ and hold it for 4 hours to obtain the final titanium alloy sample.

[0043] Step 6: Process the material into a target plate with a diameter of φ10mm and a thickness of 2mm. Use a first-level light air gun to launch a copper target plate with a diameter of φ25mm×1, impacting the target plate at speeds of 400m / s and 500m / s. Test the free surface velocity history through a probe attached to the back of the target plate.

[0044] Example 3 This embodiment includes the following steps: Step 1: The titanium powder obtained after hydrogenation and dehydrogenation is used as the main powder, with Al... Mo-Cr-Sn-Zr master alloy powder is used as an auxiliary phase. The master alloy powder is added to the main powder and uniformly mixed for 9 hours. The hydrogenated dehydrogenated titanium powder has a particle size D50 of 95 μm and an oxygen content of 0.13%, while the master alloy powder has a particle size D50 of 25 μm and an oxygen content of 0.12%. The mass percentage of each alloying element in the mixed powder is: Al 4.65%, Cr 3.50%, Mo 3.50%, Sn 2.50%, Zr 2.50%, O 0.13%, C 0.010%, N 0.035%, H 0.00120%, with the balance being Ti. Step 2: The uniformly mixed alloy powder from Step 1 is loaded into a rubber sleeve and pressed into a green compact using a cold isostatic pressing process at a pressure of 250 MPa for 60 minutes; under a vacuum of 10... -4 Under Pa protection, the pressed green billet is vacuum sintered at a high temperature of 1350℃ for 6 hours. After cooling to room temperature, a titanium alloy sintered ingot is obtained. Step 3: The sintered sample obtained in Step 2 is subjected to hot isostatic pressing (HIP). The HIP pressure is 200 MPa, the temperature is 920 °C, and the holding time is 240 min. The HIP process ensures that the sample density reaches 100%, thus obtaining a titanium alloy HIP sample.

[0045] Step 4: The hot isostatic pressing sample obtained in Step 3 is forged once at a temperature of 780℃ for 120 minutes to obtain a titanium alloy forging sample.

[0046] Step 5: Heat-treat the forged sample obtained in Step 4 at 830℃ for 3 hours, then furnace cool it to 630℃ and hold it for 8 hours to obtain the final titanium alloy sample.

[0047] Step 6: Process the material into a target plate with a diameter of φ10mm and a thickness of 2mm. Use a first-level light air gun to launch a copper target plate with a diameter of φ25mm×1, impacting the target plate at speeds of 400m / s and 500m / s. Test the free surface velocity history through a probe attached to the back of the target plate.

[0048] Comparative Example 1 Step 1: Commercially available TC17 alloy products, traditionally produced through casting and forging processes, have the following composition: Al 4.5%, Sn 2.1%, Zr 2.3%, Mo 4.1%, and Cr 4.2%. Step 2: The commercially available TC17 titanium alloy from Step 1 is processed into a target piece of the same specifications as in Example 1, and tested under the same first-level light gas gun experimental conditions with an impact velocity of 400 m / s.

[0049] Comparative Example 2 Step 1: Commercially available TC17 alloy products, traditionally produced through casting and forging processes, have the following composition: Al 4.1%, Sn 2.2%, Zr 2.2%, Mo 4.3%, and Cr 4.4%. Step 2: The commercially available TC17 titanium alloy from Step 1 is processed into a target piece with the same specifications as in Example 1, and tested at an impact velocity of 500 m / s under the same first-level light gas gun experimental conditions.

[0050] Microstructure analysis: The titanium alloy sample obtained in Example 1 was cut into metallographic samples of 8mm×8mm×4mm using wire cutting. The sample surface was polished stepwise with 80#, 300#, 600#, 1200#, 2000# and 3000# sandpaper, and then mechanically polished. Then, it was etched with HF:HNO3:H2O = 1:2:15 etching solution. The microstructure of the etched sample surface was observed using a scanning electron microscope.

[0051] External damage test: Each of the prepared titanium alloys was subjected to high-speed impact using a first-level light air gun.

[0052] Table 1 Summary of the properties of the prepared titanium alloys

[0053] Through Table 1 and Figure 1As can be seen, the spalling strength of the alloy with optimized composition in Example 1, calculated using the preparation method of this invention, is 5.39 GPa at an impact velocity of 400 m / s, while the spalling strength of the conventional alloy in Comparative Example 1 is 4.80 GPa, representing an improvement of 12.3%. At an impact velocity of 500 m / s, the spalling strength is 5.68 GPa, while the spalling strength of the conventional alloy in Comparative Example 1 is 5.13 GPa, representing an improvement of 10.7%. Spalling strength is an important quantitative indicator of resistance to external impact damage; generally, the higher the spalling strength, the stronger the material's resistance to external impact damage.

[0054] pass Figure 2 It can be seen that the proportion of grain boundaries, primary and secondary α phases in the total phase of the powder metallurgy titanium alloy prepared by the preparation method of the present invention is 45%~60%; the D50 of β grains ranges from 50μm to 85μm; the distribution path of grain boundary α phase is discontinuous; and the aspect ratio of primary α phase ranges from 2.1 to 4.2.

[0055] like Figure 3 As shown, the commercial cast-forged TC17 sample of Comparative Example 1 exhibited continuous, long, and wide primary layer cracks after impacts at velocities of 400 m / s and 500 m / s, accompanied by numerous secondary microcracks. In contrast, the sample of Example 1 showed only a small number of discontinuous, short microcracks, indicating a significant reduction in damage. This demonstrates that the optimized alloy composition of this invention effectively inhibits the initiation and propagation of layer cracks, substantially enhancing resistance to foreign object damage.

[0056] In summary, this invention achieves excellent resistance to foreign object damage through optimization of titanium alloy composition and preparation method: 1) Significantly improved resistance to dynamic impact: Through a first-stage light gas gun spalling test, it was demonstrated that the alloy optimized in this invention has a spalling strength that is more than 15% higher than that of the traditional TC17 alloy, indicating that its ability to resist internal damage under high-speed impact is significantly enhanced.

[0057] 2) Improved damage tolerance: Microstructure analysis shows that the optimized composition refines the β grain size and improves the distribution of grain boundaries and primary α phase, reducing microstructure segregation. This makes it less likely for cracks to initiate and propagate under low-velocity impact, thereby improving the material's damage tolerance.

[0058] 3) Good process compatibility: This method is based on powder metallurgy technology, which is easy to realize industrial-scale production and is suitable for manufacturing key components of aero-engines with stringent requirements for resistance to foreign object damage.

[0059] Those skilled in the art will readily understand that the above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for preparing a titanium alloy with enhanced resistance to foreign object damage, characterized in that, Includes the following steps: S1. Based on the following mass fractions: Al 4.5%~5.0%, total Mo and Cr 5.5%~7.0%, total Sn and Zr 5.0%~7.0%, with the balance being Ti; titanium powder and intermediate alloy powder are mixed to obtain a mixed powder; S2. The mixed powder is cold isostatically pressed into a green blank, and the green blank is vacuum sintered to obtain a sintered ingot. S3. The sintered ingot is subjected to hot isostatic pressing to obtain a hot isostatic pressed ingot. S4. Pre-forge the hot isostatic pressed ingot to obtain powder metallurgy forged samples; S5. Heat-treat the powder metallurgy forged sample to obtain a titanium alloy component.

2. The method for preparing the enhanced titanium alloy with improved resistance to foreign object damage as described in claim 1, characterized in that, Step S2: The cold isostatic pressure is 100MPa to 300MPa, and the holding time is 30min to 120min.

3. The method for preparing the titanium alloy with enhanced resistance to foreign object damage as described in claim 1, characterized in that, Step S2: Sintering temperature is 1300℃~1400℃, time is 2h~6h.

4. The method for preparing the titanium alloy with enhanced resistance to foreign object damage as described in claim 1, characterized in that, Step S3: The hot isostatic pressing temperature is 850℃~1000℃, the pressure is 100MPa~300MPa, and the holding time is 30min~240min.

5. The method for preparing the enhanced titanium alloy with improved resistance to foreign object damage as described in claim 1, characterized in that, Step S4: The pre-forging temperature is 10℃ to 60℃ below the phase transformation point, and the holding time is 60min to 240min.

6. The method for preparing the enhanced titanium alloy with improved resistance to foreign object damage as described in claim 1, characterized in that, Step S5, heat treatment adopts solution-aging process.

7. The method for preparing the enhanced titanium alloy with improved resistance to foreign object damage as described in claim 6, characterized in that, Step S5, the heat treatment process is as follows: the solution treatment temperature is 30℃~80℃ below the phase transformation point, the holding time is 2h~4h, and the water quenching is followed by cooling; the aging treatment temperature is 400℃~700℃, the holding time is 4h~10h, and the air cooling is followed by cooling to room temperature.

8. The method for preparing the titanium alloy with enhanced resistance to foreign object damage as described in claim 1, characterized in that, The oxygen content of the titanium powder is no more than 0.15%, the oxygen content of the intermediate alloy powder is no more than 0.12%, and the mixing time in step S1 is 1h to 24h.

9. The method for preparing the enhanced titanium alloy with improved resistance to foreign object damage as described in any one of claims 1-8, characterized in that, The titanium powder is mixed with the intermediate alloy powder according to the following mass fractions: Al 4.5%~5.0%, Cr 3.0%~3.5%, Mo 2.5%~3.5%, Sn 2.5%~3.5%, Zr 2.5%~3.0%, with the balance being Ti; a mixed powder is obtained by mixing titanium powder with intermediate alloy powder.

10. A titanium alloy with enhanced resistance to foreign object damage, characterized in that, It is prepared by the method for preparing titanium alloy with enhanced resistance to foreign object damage as described in any one of claims 1-9.

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