Titanium alloy thin-walled sheet superplastic forming performance and low-loss control method of formed component

Abstract

The application discloses a low-loss control method for superplastic forming performance of a titanium alloy thin-wall plate and a formed component, and relates to the technical field of superplastic forming control of the titanium alloy thin-wall plate. The application solves the performance loss problem of the thin-wall titanium alloy in the superplastic forming. The method comprises the following steps: placing the titanium alloy thin-wall plate into a vacuum hydrogenation furnace, sequentially performing vacuumizing, temperature rising, temperature keeping and hydrogen heat treatment, and finally completing hydrogenation; discharging hydrogen and introducing argon, so that the titanium alloy thin-wall plate after hydrogenation is cooled to room temperature; performing a superplastic forming process on the titanium alloy thin-wall plate after cooling to obtain a formed component; cooling the formed component to room temperature and placing the formed component into a vacuum furnace, vacuumizing and then heating to a temperature required by vacuum annealing to perform dehydrogenation; cooling the component after dehydrogenation to room temperature to obtain a titanium alloy component with low performance loss. The application is suitable for the technical field of superplastic forming of the titanium alloy thin-wall plate.

Description

Technical Field

[0001] This invention relates to the field of superplastic forming control technology for thin-walled titanium alloy sheets, and more particularly to a control technology for reducing performance loss during the superplastic forming process by introducing hydrogen. Background Technology

[0002] Superplastic forming is currently recognized as one of the advanced forming technologies for manufacturing thin-walled, complex integral structures. This technology offers significant advantages in reducing the weight of aircraft structures and lowering production costs, and is hailed as a pioneering technology in modern aerospace production. However, like other hot-working processes, superplastic forming also slightly degrades the properties of titanium alloys. To ensure the safe use of superplastic-formed components and fully leverage the advantages of superplastic forming, it is crucial to minimize performance losses during the process.

[0003] Patent document CN103785684A, published on May 14, 2014, discloses a method for preparing fine-grained TA15 titanium alloy thin plates for superplastic forming. This method produces fine-grained TA15 titanium alloy thin plates with a thickness of 0.6 mm to 2.5 mm, an elongation of not less than 715%, a grain size ≤ 6 μm, and a uniform equiaxed grain structure in both the transverse and longitudinal directions, suitable for specific superplastic forming processes. This method controls grain size and morphology through multiple hot rolling operations within a range of temperatures below the β-transformation temperature, consistent with the principle of fine-grained superplasticity. However, this method involves numerous steps, and due to the long superplastic forming time, it cannot suppress grain growth during superplastic forming.

[0004] A patent document published on September 28, 2018, CN108580884A, discloses a hydrogen-treated rolling composite process for improving the microstructure of additively manufactured titanium alloys. This composite process involves hydrogenating titanium alloy powder and combining it with a layer-by-layer rolling process. Through multiple cycles of printing and rolling, a printed part with a refined microstructure is successfully prepared. Finally, hydrogen is removed by vacuum annealing. This composite process significantly improves the microstructure of additively manufactured titanium alloys without changing the composition of the titanium alloy. This method is mainly used for hydrogen treatment of titanium alloy powder and requires extremely high pressure from the rolling process to achieve the desired results. Superplastic forming is mainly used for sheet metal, where the forming process does not require high pressure and the formed part has a tortuous shape. Rolling can only produce straight structures and is difficult to produce tortuous parts. Although this method allows for reasonable control of grain size, it is not suitable for superplastic forming.

[0005] A paper published on July 1, 2007, titled "Research on the Mechanism of Hydrogen-Induced Plasticization and its High-Temperature Deformation Law of Titanium Alloys," analyzes the influence of hydrogen as a temporary alloying element on the mechanical behavior and microstructure evolution of titanium alloys during high-temperature plastic deformation. It proposes a hydrogen-induced high-temperature plasticization mechanism for titanium alloys, based on the influence of deformation temperature and strain rate on the deformation behavior of hydride titanium alloys. The dispersed titanium hydride precipitated by hydrogen provides numerous nucleation sites, and the decomposition of titanium hydride during dehydrogenation promotes recrystallization and refines the grains. Simultaneously, hydrogen oxidization expands the β-phase region, playing a role in plasticization and reducing flow stress; the hydrogen-induced weakening effect and the reduction of dislocation density also contribute to high-temperature plasticity. This method demonstrates that a reasonable amount of hydrogen oxidization can not only refine the grains but also significantly improve high-temperature plasticity. This method is applicable to conventional hot working of titanium alloys, and the general implementation temperature range is 480℃~940℃. However, the temperature required for superplasticity is 0.5~0.65Tm (Tm is the melting point of the material) and the strain rate is generally 1×10-3~1×10-4 (far lower than conventional hot working).

[0006] Superplastic forming temperatures are typically between 0.5 and 0.65 Tm (Tm being the material's melting point), and the required time is generally over 6 hours. Nowadays, superplastic forming is often combined with diffusion bonding, forming a superplastic forming / diffusion bonding process, further extending the forming time. Due to the high temperature and long time span, the grains are prone to abnormal coarsening, resulting in a significant reduction in the performance of the formed component compared to the base material. Summary of the Invention

[0007] The purpose of this invention is to solve the performance loss problem of thin-plate titanium alloys in superplastic forming, especially the problem that the overall performance of complex components is significantly lower than that of the original base material due to the severe reduction in the thickness of the titanium alloy sheet and the coarse grains during superplastic forming.

[0008] To achieve the above objectives, the present invention provides the following solution:

[0009] This invention provides a method for controlling the superplastic forming performance of thin-walled titanium alloy sheets and the low-loss of formed components. The method is as follows:

[0010] S1. Place the titanium alloy thin-walled plate into a vacuum hydrogen placement furnace and sequentially perform vacuuming, heating, heat preservation, and hydrogen heat treatment to complete the hydrogen placement.

[0011] S2. Expel hydrogen gas and introduce argon gas to cool the titanium alloy thin-walled plate after hydrogen exposure to room temperature.

[0012] S3. The cooled titanium alloy thin-walled sheet is subjected to superplastic forming process to obtain the formed component;

[0013] S4. Cool the formed component to room temperature and place it in a vacuum furnace. After evacuation, heat it to the temperature required for vacuum annealing to remove hydrogen.

[0014] S5. Cool the dehydrogenated component to room temperature to obtain a titanium alloy component with low performance loss.

[0015] Furthermore, in a preferred embodiment, in step S1 above, the titanium alloy thin-walled plate is first cleaned with anhydrous ethanol and then dried with cold air before being placed in a vacuum hydrogen furnace.

[0016] Furthermore, in a preferred embodiment, the heat preservation time in step S1 is 5 min to 30 min.

[0017] Furthermore, in a preferred embodiment, the vacuum degree of the aforementioned vacuum hydrogen placement furnace is 1×10⁻⁶. -2 Below Pa;

[0018] The hydrogen placement temperature is 450℃~850℃, the hydrogen pressure is -0.09MPa~0MPa, and the hydrogen placement time is 30min~2h.

[0019] Furthermore, in a preferred embodiment, in step S3 above, the cooled titanium alloy thin-walled sheet is first cleaned with anhydrous ethanol, then dried with cold air, and then subjected to a superplastic forming process.

[0020] Furthermore, in a preferred embodiment, the cleaned titanium alloy thin-walled sheet is placed in a superplastic forming machine for superplastic forming.

[0021] Furthermore, in a preferred embodiment, the superplastic forming temperature in the above-mentioned superplastic forming process is 500–900°C.

[0022] Furthermore, in a preferred embodiment, the vacuum degree of the vacuum furnace in step S4 above is 1×10⁻⁶. -2 Below Pa.

[0023] Furthermore, in a preferred embodiment, the temperature is raised to 650–850°C in step S4 above, and the dehydrogenation time is 6–12 hours.

[0024] The present invention also provides a titanium alloy component with low performance loss, which is achieved based on the superplastic forming performance of titanium alloy thin-walled sheet and the low loss control method of formed component as described in any one of the above.

[0025] The beneficial effects of this invention are as follows:

[0026] 1. This invention provides a method for controlling the superplastic forming performance of titanium alloy thin-walled sheets and the low loss of formed components. First, the titanium alloy thin-walled sheet is hydrogenated using a hydrogenation process. Hydrogen-induced plasticity is employed to enhance the high-temperature plasticity and superplasticity of the titanium alloy thin-walled sheet, providing strong plastic deformation capabilities to address the challenges of mold fitting in complex component cavities and the drastic reduction in cavity fillet thickness. This reduces the risk of forming failure and the performance loss caused by uneven wall thickness in the formed part. Then, the superplastic-formed component undergoes vacuum dehydrogenation treatment, allowing the "temporary" element hydrogen in the titanium alloy to escape, preventing hydrogen embrittlement during use. This also promotes the recrystallization of grains grown after hot working, restoring their original properties and contributing to low performance loss from a microstructural perspective.

[0027] 2. A method for controlling the superplastic forming performance of titanium alloy thin-walled sheets and the low-loss of formed components, which can significantly improve the superplastic forming limit of titanium alloys and suppress the decrease in mechanical properties of titanium alloys at high temperatures and long holding times, meeting the relevant technical indicators before and after superplastic forming. Simultaneously, after placing the titanium alloy with hydrogen, hydrogen-induced plasticity can be used to significantly improve the forming limit of the superplastic forming process; after forming, the formed components undergo dehydrogenation treatment, resulting in grain refinement and restoring the original properties of the titanium alloy.

[0028] 3. This invention provides a method for controlling the low loss of superplastic forming performance of titanium alloy thin-walled plates. After hydrogenation-superplastic forming-dehydrogenation treatment of titanium alloy thin-walled plates, the difficulty of forming complex components can be greatly reduced. At the same time, the overall performance of the formed components is high and the material performance loss is very low.

[0029] This invention is applicable to the field of superplastic forming technology for thin-walled titanium alloy sheets. Attached Figure Description

[0030] Figure 1 This is a microstructure diagram of TA15 after hydrogenation as described in Embodiment Eleven;

[0031] Figure 2 This is a diagram of the original microstructure of TA15 after heat treatment as described in Embodiment Eleven;

[0032] Figure 3 This is a tissue diagram of TA15 after dehydrogenation in the tissue difference study described in Implementation Method Eleven;

[0033] Figure 4 This is a microstructure diagram of TA15 after dehydrogenation in the superplasticity study described in Embodiment Eleven;

[0034] Figure 5 This is a diagram of a four-layer structure prepared by superplastic forming of the hydrogenated TA15 sheet material as described in Embodiment Eleven. Detailed Implementation

[0035] In the following description, specific details such as particular system architectures and techniques are set forth for illustrative purposes and not for limitation, in order to provide a thorough understanding of the embodiments of this application. However, those skilled in the art will understand that this application may also be implemented in other embodiments without these specific details. In other instances, detailed descriptions of well-known systems, apparatuses, circuits, and methods are omitted so as not to obscure the description of this application with unnecessary detail.

[0036] It should be understood that, when used in this specification and the appended claims, the term "comprising" indicates the presence of the described features, integrals, steps, operations, elements and / or components, but does not exclude the presence or addition of one or more other features, integrals, steps, operations, elements, components and / or collections thereof.

[0037] It should also be understood that the terminology used in this application specification is for the purpose of describing particular embodiments only and is not intended to limit the application. As used in this application specification and the appended claims, the singular forms “a,” “an,” and “the” are intended to include the plural forms unless the context clearly indicates otherwise.

[0038] The specific embodiments of the present invention will be further described in detail below with reference to the accompanying drawings and examples. The following examples will help those skilled in the art to further understand the present invention, but do not limit the present invention in any way. It should be noted that those skilled in the art can make several changes and improvements without departing from the concept of the present invention, and these all fall within the protection scope of the present invention.

[0039] Implementation Method 1: This implementation method provides a method for controlling the superplastic forming performance of titanium alloy thin-walled sheets and the low-loss control of formed components. The low-loss control method is as follows:

[0040] S1. Place the titanium alloy thin-walled plate into a vacuum hydrogen placement furnace and sequentially perform vacuuming, heating, heat preservation, and hydrogen heat treatment to complete the hydrogen placement.

[0041] S2. Expel hydrogen gas and introduce argon gas to cool the titanium alloy thin-walled plate after hydrogen exposure to room temperature.

[0042] S3. The cooled titanium alloy thin-walled sheet is subjected to superplastic forming process to obtain the formed component;

[0043] S4. Cool the formed component to room temperature and place it in a vacuum furnace. After evacuation, heat it to the temperature required for vacuum annealing to remove hydrogen.

[0044] S5. Cool the dehydrogenated component to room temperature to obtain a titanium alloy component with low performance loss.

[0045] In practical applications, the specific method for controlling low-loss superplastic forming performance of titanium alloy thin-walled plates according to this embodiment is as follows:

[0046] S1. Place the titanium alloy thin-walled plate into a vacuum hydrogen placement furnace, and sequentially perform vacuuming, heating, temperature holding and hydrogen heat treatment to complete the hydrogen placement.

[0047] Specifically:

[0048] First, clean the surface of the titanium alloy thin-walled sheet with anhydrous ethanol or acetone and ultrasonic vibration to remove stains, and then dry it with cold air.

[0049] Next, the cleaned titanium alloy thin-walled sheet is placed in a vacuum hydrogen furnace and evacuated to a vacuum level of 1×10⁻⁶ at room temperature. -2 Below Pa.

[0050] Then, the temperature is raised to the optimal temperature for hydrogen placement of the titanium alloy thin-walled plate, which is 450-850°C, and maintained for 5-30 minutes to ensure uniform temperature inside the furnace, thereby ensuring uniform heating of the titanium alloy thin-walled plate. In practical applications, the larger the furnace chamber of the vacuum hydrogen placement furnace, the thicker the titanium alloy thin-walled plate, and the longer the holding time.

[0051] Finally, hydrogen is introduced into a vacuum hydrogen-filling furnace that has reached the preset temperature until the required hydrogen pressure of -0.09 to 0 MPa is reached. 0 MPa is the standard atmospheric pressure. The hydrogen pressure is maintained and the furnace is kept at a temperature of 1 to 2 hours in a hydrogen atmosphere to complete the hydrogen filling process. This process uses hydrogen-induced plasticity to improve the high-temperature plasticity and superplasticity of thin-walled titanium alloy sheets. It uses strong plastic deformation capabilities to address the challenges of molding complex component cavities and the problem of drastic reduction in the thickness of cavity fillets.

[0052] S2. Expel hydrogen gas and introduce argon gas to cool the titanium alloy thin-walled plate after hydrogen exposure to room temperature.

[0053] Specifically, after hydrogen treatment, the hydrogen gas is discharged and high-purity argon gas with a purity of ≥99.999 is introduced, so that the thin-walled titanium alloy plate after hydrogen treatment is cooled to room temperature in an argon atmosphere.

[0054] S3. The cooled titanium alloy thin-walled sheet is subjected to superplastic forming process to obtain the formed component;

[0055] Specifically, the cooled titanium alloy thin-walled sheet is placed in a superplastic forming machine, and high-purity argon gas is used to provide pressure for superplastic forming. This process can also be combined with diffusion bonding to form a superplastic forming / diffusion bonding process to obtain the formed component.

[0056] S4. Cool the formed component to room temperature and place it in a vacuum furnace. After evacuation, heat it to the temperature required for vacuum annealing to remove hydrogen.

[0057] Specifically:

[0058] The obtained shaped component is placed in a vacuum furnace, evacuated, and then heated to the temperature required for vacuum annealing for dehydrogenation treatment. The dehydrogenation time is 6–12 hours, and the dehydrogenation temperature is 650–850℃. This process removes hydrogen from the shaped component, allowing the "temporary" hydrogen in the titanium alloy to escape, preventing hydrogen embrittlement during use, promoting recrystallization of the grains that have grown after hot working, restoring their original properties, and thus contributing to low performance loss from a microstructural perspective.

[0059] S5. Cool the dehydrogenated component to room temperature to obtain a titanium alloy component with low performance loss.

[0060] This embodiment provides a method for controlling low-loss performance of superplastic forming of titanium alloy thin-walled plates. First, the titanium alloy thin-walled plate is hydrogenated using a hydrogenation process. Hydrogen-induced plasticity is employed to enhance the high-temperature plasticity and superplasticity of the titanium alloy thin-walled plate, providing strong plastic deformation capabilities to address the challenges of mold fitting in complex component cavities and the drastic reduction in cavity fillet thickness. This reduces the risk of forming failure and the performance loss caused by uneven wall thickness in the formed part. Then, the superplastic-formed component undergoes vacuum dehydrogenation treatment, allowing the "temporary" hydrogen element in the titanium alloy to escape, preventing hydrogen embrittlement during use. This also promotes the recrystallization of grains that have grown after hot working, restoring their original properties and contributing to low performance loss from a microstructural perspective.

[0061] This embodiment provides a method for controlling the low loss of superplastic forming performance of titanium alloy thin-walled plates. After hydrogenation-superplastic forming-dehydrogenation treatment of titanium alloy thin-walled plates, the difficulty of forming complex components can be greatly reduced. At the same time, the overall performance of the formed components is high and the material performance loss is very low.

[0062] Implementation Method 2: This implementation method is a detailed description of step S1 in the method for controlling the superplastic forming performance of titanium alloy thin-walled plates and the low loss of formed components as described in Implementation Method 1.

[0063] In step S1, the titanium alloy thin-walled plate is first cleaned with anhydrous ethanol and then dried with cold air before being placed in a vacuum hydrogen furnace.

[0064] In practical applications, this embodiment uses anhydrous ethanol or acetone in conjunction with ultrasonic vibration to clean stains on the surface of thin-walled titanium alloy plates.

[0065] Implementation Method 3: This implementation method is an example of the temperature holding time in step S1 of the method for controlling the superplastic forming performance of titanium alloy thin-walled sheet and the low loss of formed components described in Implementation Method 2.

[0066] The temperature holding time in step S1 is 5 min to 30 min.

[0067] In practical applications, the temperature holding time of this embodiment is 5 to 30 minutes, which makes the temperature inside the furnace uniform, and thus makes the titanium alloy thin-walled plate heated evenly. In practical applications, the larger the furnace chamber of the vacuum hydrogen furnace, the thicker the titanium alloy thin-walled plate, and the longer the holding time.

[0068] Implementation Method 4: This implementation method is an example of the vacuum degree, hydrogen placement temperature, hydrogen pressure, and hydrogen placement time of the vacuum hydrogen placement furnace in step S1 of the method for controlling the superplastic forming performance of titanium alloy thin-walled plates and the low loss of formed components described in Implementation Method 3.

[0069] The vacuum degree of the vacuum hydrogen placement furnace is 1×10⁻⁶. -2 Below Pa;

[0070] The hydrogen placement temperature is 450℃~850℃, the hydrogen pressure is -0.09MPa~0MPa, and the hydrogen placement time is 30min~2h.

[0071] In practical applications, the vacuum level of the vacuum hydrogen placement furnace must reach 1×10⁻⁶. -2 The pressure is below 0 MPa, which makes the titanium alloy less prone to oxidation during hydrogen immersion and also prevents air from entering the high-temperature hydrogen atmosphere and causing an explosion. The hydrogen immersion temperature is 450℃~850℃, the hydrogen pressure is -0.09MPa~0MPa, and the hydrogen immersion time is 30min~2h.

[0072] Implementation Method 5: This implementation method is an example of step S3 in the method for controlling the superplastic forming performance of titanium alloy thin-walled plates and the low loss of formed components described in Implementation Method 1.

[0073] In step S3, the cooled titanium alloy thin-walled sheet is first cleaned with anhydrous ethanol, then dried with cold air, and then subjected to superplastic forming process.

[0074] In practical applications, this embodiment uses anhydrous ethanol or acetone in conjunction with ultrasonic vibration to clean stains on the surface of thin-walled titanium alloy plates.

[0075] Implementation Method Six: This implementation method is an example of the machine used in step S3 of the superplastic forming process in the method for controlling the superplastic forming performance of titanium alloy thin-walled plates and the low loss of formed components described in Implementation Method Five.

[0076] The cleaned titanium alloy thin-walled sheet is placed into a superplastic forming machine for superplastic forming process.

[0077] Implementation Method Seven: This implementation method is an example of the superplastic forming temperature in the superplastic forming process of the superplastic forming performance of titanium alloy thin-walled sheet and the low-loss control method of formed components described in Implementation Method Six.

[0078] The superplastic forming temperature in the superplastic forming process is 500–900℃.

[0079] Implementation Method 8: This implementation method is an example of the vacuum degree of the vacuum furnace in step S4 of the method for controlling the superplastic forming performance of titanium alloy thin-walled plates and the low loss of formed components described in Implementation Method 7.

[0080] In step S4, the vacuum level of the vacuum furnace is 1×10⁻⁶. -2 Below Pa.

[0081] Implementation Method Nine: This implementation method is an example of the heating temperature and dehydrogenation time in step S4 of the method for controlling the superplastic forming performance of titanium alloy thin-walled plates and the low loss of formed components described in Implementation Method Eight.

[0082] In step S4, the temperature is raised to 650–850°C, and the dehydrogenation time is 6–12 hours.

[0083] Implementation Method 10: This implementation method provides a titanium alloy component with low performance loss. The titanium alloy component is realized based on the superplastic forming performance of titanium alloy thin-walled sheet and the low loss control method of formed component described in any one of Implementation Methods 1 to 9.

[0084] Implementation Method 11, see below Figures 1 to 5 This embodiment is a description of a titanium alloy component with low performance loss obtained by a method for controlling the superplastic forming performance of titanium alloy thin-walled sheet and the low loss of formed components as described in any one of embodiments one through nine.

[0085] The main research includes studies on the differences between the original microstructure and the microstructure after hydrogen treatment and dehydrogenation treatment of TA15 titanium alloy, superplasticity studies on tensile specimens of original TA15 titanium alloy and hydrogen-treated specimens, and superplastic forming and diffusion bonding studies on hydrogen-treated TA15 four-layer structure.

[0086] I. Study on the differences in microstructure between TA15 titanium alloy under original conditions and those after hydrogen treatment and dehydrogenation:

[0087] Step 1: Place three TA15 titanium alloy samples, each 10mm × 10mm in size and 2mm thick, cut by wire cutting, into a water bath containing alcohol. Remove the stains from the sample surface by high-frequency ultrasonic vibration for 5–10 minutes, and then dry them with a hairdryer on a cool setting. Sample 1 is heat-treated, samples 2 and 3 are hydrogenated, and sample 3 is dehydrogenated.

[0088] Step 2: Place the cleaned samples No. 2 and No. 3 into the hydrogen furnace, and then evacuate to 3.1 × 10⁻⁶ at room temperature. - 3 Pa.

[0089] Step 3: Start heating at 15℃ / min, raise the temperature to 850℃, and hold for 5 minutes.

[0090] Step 4: Introduce hydrogen gas into the vacuum furnace to achieve a hydrogen pressure of -0.09 MPa, and maintain this temperature and pressure for 1 hour. After the experiment, vent the hydrogen gas and introduce high-purity argon gas to cool the plate in argon. The hydrogen absorption rate of TA15 after the hydrogen absorption test was 0.37, and the hydrogen-absorbed microstructure is as follows... Figure 1 As shown.

[0091] Step 5: Sample No. 1 was heat-treated in an argon atmosphere at the same temperature and for the same holding time. The original microstructure after heat treatment is as follows: Figure 2 As shown.

[0092] Step Six: The hydrogen-treated sample No. 3 was subjected to vacuum annealing at 800℃ for 8 hours. The microstructure of TA15 after dehydrogenation is as follows... Figure 3 As shown.

[0093] By comparison, it is clear that after hydrogenation and dehydrogenation treatment, the grains of TA15 titanium alloy are significantly refined, which can reduce the performance loss after superplastic forming.

[0094] II. Superplasticity study of raw, hydrogen-exposed tensile specimens of TA15 titanium alloy:

[0095] Step 1: The TA15 titanium alloy high-temperature tensile test specimens cut by wire cutting are cleaned with anhydrous ethanol and ultrasonic vibration. Tensile specimen No. 1 was cut from the original TA15 sheet, and tensile specimen No. 2 was subjected to hydrogen treatment.

[0096] Step 2: Place the cleaned sample No. 2 into the hydrogen furnace, and then evacuate to 3.5 × 10⁻⁶ at room temperature. -3 Pa.

[0097] Step 3: Start heating at 15℃ / min, raise the temperature to 850℃, and hold for 5 minutes.

[0098] Step 4: Introduce hydrogen gas into the vacuum furnace to achieve a hydrogen pressure of -0.03 MPa, and maintain this temperature and pressure for 1 hour. After the experiment, vent the hydrogen gas and introduce high-purity argon gas to cool the plate in the argon atmosphere.

[0099] Step 5: Perform high-temperature tensile testing on the original TA15 sample and the hydrogen-treated sample respectively. The test temperature is 880℃, the optimal superplastic forming temperature of TA15, and the tensile strain rate is 0.01.

[0100] Clearly, the ductility of TA15 titanium alloy is significantly enhanced after hydrogen treatment, such as... Figure 4 As shown.

[0101] III. Study on Superplastic Forming and Diffusion Bonding of Hydrogen-Containing TA15 Four-Layer Structure:

[0102] Step 1: Clean the TA15 board with a panel thickness of 0.5mm, a core board thickness of 0.4mm, and a size of 400mm×400mm with acetone and dry it with a blower.

[0103] Step 2: Stack the four cleaned titanium alloy sheets into a vacuum hydrogen furnace. To ensure even heating and facilitate hydrogen introduction, separate the four sheets with small metal spacers. Evacuate the furnace to 5×10⁻⁶ at room temperature. -3 Pa.

[0104] Step 3: Start heating at 10℃ / min, raise the temperature to 850℃, and hold for 20 minutes.

[0105] Step 4: After the heat preservation is completed, hydrogen gas is introduced into the vacuum furnace to make the hydrogen pressure reach -0.03MPa and automatically maintain the hydrogen pressure. After heat preservation for 1 hour, the vacuum is evacuated for 10 minutes to remove the hydrogen gas. High-purity argon gas is then introduced to cool the plate in argon gas.

[0106] Step 5: Superplastic forming and diffusion bonding of four TA15 titanium alloy sheets, resulting in a four-layer structure as shown below. Figure 5 As shown.

[0107] Compared to unhydrogenated TA15 titanium alloy, hydrogenated titanium alloy has a greater forming limit, more uniform component thickness, smaller triangular areas, and a smooth, wrinkle-free surface, resulting in less performance loss compared to the original base material.

[0108] In summary, the method for controlling the low-loss superplastic forming performance of titanium alloy thin-walled plates described in this embodiment can significantly improve the superplastic forming limit of titanium alloys and suppress the decrease in mechanical properties of titanium alloys at high temperatures and long holding times, meeting the relevant technical indicators before and after superplastic forming. Furthermore, after hydrogen is introduced into the titanium alloy, hydrogen-induced plasticity can be used to significantly improve the forming limit of the superplastic forming process; after forming, the formed component undergoes dehydrogenation treatment, resulting in grain refinement and restoring the original properties of the titanium alloy.

[0109] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0110] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0111] The above description is merely an embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of the claims of the present invention.

Claims

1. A method for controlling the superplastic forming performance of titanium alloy thin-walled sheets and the low-loss of formed components, characterized in that, The method is as follows: S1. Place the titanium alloy thin-walled plate into a vacuum hydrogen placement furnace and sequentially perform vacuuming, heating, heat preservation, and hydrogen heat treatment to complete the hydrogen placement. The vacuum degree of the vacuum hydrogen placement furnace is 1×10⁻⁶. -2 Below Pa; hydrogen placement temperature is 450℃~850℃, hydrogen pressure is -0.09MPa~0MPa, hydrogen placement time is 30min~2h; heat preservation time is 5min~30min; S2. Expel hydrogen gas and introduce argon gas to cool the titanium alloy thin-walled plate after hydrogen exposure to room temperature. S3. The cooled titanium alloy thin-walled sheet is subjected to superplastic forming process to obtain the formed component; The superplastic forming temperature in the superplastic forming process is 500~900℃; S4. Cool the formed component to room temperature and place it in a vacuum furnace. After evacuation, heat it to the temperature required for vacuum annealing to remove hydrogen. The vacuum degree of the vacuum furnace is 1×10 -2 Below Pa; heat to 650~850℃, dehydrogenation time 6~12h; S5. Cool the dehydrogenated component to room temperature to obtain a titanium alloy component with low performance loss.

2. The method for controlling the superplastic forming performance of titanium alloy thin-walled plates and the low-loss of formed components according to claim 1, characterized in that, In step S1, the titanium alloy thin-walled plate is first cleaned with anhydrous ethanol and then dried with cold air before being placed in a vacuum hydrogen furnace.

3. The method for controlling the superplastic forming performance of titanium alloy thin-walled plates and the low-loss of formed components according to claim 1, characterized in that, In step S3, the cooled titanium alloy thin-walled sheet is first cleaned with anhydrous ethanol, then dried with cold air, and then subjected to superplastic forming process.

4. The method for controlling the superplastic forming performance of titanium alloy thin-walled plates and the low-loss of formed components according to claim 3, characterized in that, The cleaned titanium alloy thin-walled sheet is placed into a superplastic forming machine for superplastic forming process.

5. A titanium alloy component with low performance loss, characterized in that, The titanium alloy component is achieved based on the method for controlling the superplastic forming performance of titanium alloy thin-walled plates and the low loss of formed components as described in any one of claims 1-4.

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