A hot creep forming process method for titanium alloys

Abstract

The application relates to the technical field of hot press forming of titanium alloy parts, and particularly discloses a hot creep forming process method of a titanium alloy, which specifically comprises the following steps: (1) cleaning the surface of TA32 titanium alloy blank and a die by using a cleaning solvent until no dust, corrosion, grease, impurities and other dirt are present on the surface; (2) installing the die to a hot forming machine; (3) brushing a high-temperature resistant lubricant on the surface of the TA32 titanium alloy blank and the die; (4) starting the hot forming machine to heat the die, and heating the die to a temperature range of 780-820 DEG C; (5) placing the TA32 titanium alloy blank into the hot forming machine, and preheating for 5-12 min; (6) clamping the upper die and the lower die of the die to apply to the preheated TA32 titanium alloy blank, and taking out the part after heat preservation for 10-15 min under the pressure condition. The scheme mainly proposes an optimization scheme for the hot creep forming process of the TA32 titanium alloy, so that the forming precision is improved.

Description

Technical Field

[0001] This invention relates to the field of hot pressing forming technology for titanium alloy parts, and more specifically to a hot creep forming process method for titanium alloys. Background Technology

[0002] Titanium alloys are a new type of structural material with excellent comprehensive properties, such as low density, high specific strength, good fatigue strength and crack propagation resistance, good low-temperature toughness, and good corrosion resistance. Therefore, they have been widely used in aviation, aerospace, and shipbuilding industries. For components such as the inner and outer fairings of aero-engines, guide vane inner rings, and compressor intake chambers, hot-pressing technology using titanium alloy sheets is widely used internationally. In my country's aerospace manufacturing processes, titanium alloy materials and their hot-forming technology are also gradually developing.

[0003] For example, the article "Superplastic Forming / Diffusion Joining Process of TA32 Titanium Alloy Double-Layer Structure Parts," published in the March 2022 issue of the "Journal of Plastic Engineering" (Vol. 29, No. 3), points out that "rapid iteration and upgrading of aircraft models continuously raise the requirements for the performance of new-generation aircraft in terms of flight speed, structure, structural weight, and service life, which places increasingly higher demands on the materials selected for aircraft component manufacturing. Therefore, the materials used in the preparation of new-generation aircraft components need to ensure the service performance of the aircraft in complex and harsh environments, while also ensuring that the aircraft achieves high-tech quality. To achieve high-speed flight, it is necessary to solve the heat resistance problem of components under high-speed flight conditions. Titanium alloy is one of the most widely used high-temperature structural materials in aircraft, capable of withstanding temperatures of 400-500°C." While commonly used titanium alloys like TC4 and TA15 are no longer sufficient to meet the increasingly demanding performance requirements of new-generation aircraft, high-temperature alloys capable of operating in environments of 600-650℃ are becoming the preferred material for future aircraft design and manufacturing. my country's independently developed TA32 high-temperature titanium alloy has attracted attention in the domestic aerospace component manufacturing sector and is gradually becoming a research focus for design departments and aircraft manufacturers. It is evident that with my country's research on titanium alloys, the types of titanium alloy materials are gradually increasing, and their performance is also gradually improving; therefore, in key areas such as aerospace manufacturing, the superior high-temperature mechanical properties of TA32 titanium alloy will inevitably replace commonly used titanium alloy materials.

[0004] However, as mentioned in the above-mentioned cited document, "Domestic research on TA32 titanium alloy is mostly focused on basic research such as superplasticity, microstructure changes and constitutive model establishment, with few studies on the engineering forming and manufacturing process of this material"; the above-mentioned cited document is based on this and "analyzes the influence of forming temperature and strain rate on the superplasticity of TA32 titanium alloy through high-temperature mechanical property tests, and obtains the superplastic forming process parameters of TA32 titanium alloy".

[0005] Currently, common forming technologies for titanium alloys include superplastic forming and thermal creep forming. Superplastic forming involves heating the titanium alloy to a superplastic temperature, causing it to undergo superplastic deformation and gradually approach the mold surface until it completely conforms to the mold, creating a part identical to the mold surface. Superplastic forming technology SPF and superplastic forming / diffusion bonding technology SPF / DB are characterized by low cost and high efficiency. The cited documents mentioned above describe research on superplastic forming and diffusion bonding processes. Thermal creep forming utilizes the creep characteristics of metallic materials at high temperatures, where the sheet metal slowly deforms to meet manufacturing requirements. After heating, when the temperature of the titanium alloy reaches above 500℃, its plasticity significantly increases, but its resistance to deformation decreases. Furthermore, heating can eliminate internal stress in the material, reduce springback, and improve forming accuracy. However, springback issues still exist with thermal creep forming technology.

[0006] To reduce springback, titanium alloy sheet metal parts are generally formed using superplastic forming. However, superplastic forming involves high temperatures (up to 950℃), slow forming rates, and low production efficiency. Furthermore, prolonged exposure to high temperatures increases grain size, negatively impacting the material's formability. Hot creep forming, on the other hand, has relatively lower heating temperatures and faster forming speeds. However, there is currently no research on hot creep forming processes specifically for TA32 titanium alloys, and using the process parameters for common titanium alloys like TC4 and TA15 cannot achieve the required forming accuracy for TA32 titanium alloys. Summary of the Invention

[0007] The purpose of this invention is to provide a hot creep forming process for titanium alloys, and to propose an optimized scheme for the hot creep forming process of TA32 titanium alloys to improve forming accuracy.

[0008] The hot creep forming process for titanium alloys includes the following steps:

[0009] (1) Clean the TA32 titanium alloy blank and mold surface with cleaning solvent until the surface is free of dust, corrosion, grease, impurities and other contaminants;

[0010] (2) Install the mold onto the thermoforming machine;

[0011] (3) Apply high-temperature resistant lubricant to the surface of TA32 titanium alloy blank and mold;

[0012] (4) Start the thermoforming machine to heat the mold and heat the mold to a temperature range of 780-820℃;

[0013] (5) Place the TA32 titanium alloy blank into the hot forming machine and preheat for 5-12 minutes;

[0014] (6) The upper and lower molds of the mold are closed to apply pressure to the preheated TA32 titanium alloy blank, and the part is removed after being kept under pressure for 10-15 minutes.

[0015] The beneficial effects of this plan are as follows:

[0016] When creep forming commonly used titanium alloy materials, the forming temperature is usually controlled within the range of 630-650℃. However, when creep forming TA32 titanium alloy, controlling the forming temperature within this range results in a high springback rate in the TA32 titanium alloy blank, leading to lower precision in the finished product. To reduce the springback rate and improve the precision of the finished product, superplastic forming technology is usually adopted in this case. As concluded in the article "Superplastic Forming / Diffusion Joining Process of TA32 Titanium Alloy Double-Layer Structure Parts" in Volume 29, Issue 3 of the "Journal of Plastic Engineering," "the superplastic forming temperature is selected as 940℃." However, superplastic forming has disadvantages such as high forming temperature and low efficiency. This solution, on the other hand, determines the forming temperature under creep forming conditions for TA32 titanium alloy, improving the forming efficiency and precision of TA32 titanium alloy parts. Compared with superplastic forming technology, this solution has a lower forming temperature and shorter forming time, which can avoid the increase in grain size under high temperature conditions, thus preventing the reduction of mechanical properties of TA32 titanium alloy.

[0017] Preferred option 1: As a further optimization of the basic option, the cleaning solvent in step (1) is acetone or alcohol.

[0018] Preferred Option 2: As a further optimization of Preferred Option 1, the high-temperature lubricant in step (3) is boron nitride; in the creep forming process of titanium alloy, the commonly used lubricant is graphite, but graphite is not suitable for high-temperature forming environment. Therefore, in this preferred option, boron nitride is used as the lubricant.

[0019] Preferred Option 3: As a further optimization of Preferred Option 2, in step (1) when cleaning the TA32 titanium alloy blank and mold surface, the cleaning solvent is slowly poured onto the wiping cloth to moisten it, and then the blank and mold surfaces are wiped with the wiping cloth. Using the cleaning solvent to moisten the wiping cloth and then wiping the blank and mold surfaces can avoid wasting and contaminating the cleaning solvent.

[0020] Preferred Option 4: As a further optimization of Preferred Option 3, in step (1), after cleaning the TA32 titanium alloy blank and mold surface with a cleaning solvent, the wetted part surface is wiped dry with a dry cloth; the cloth used to wipe the part surface can be reused to clean the blank again, thereby reducing the direct evaporation of the cleaning solvent and improving the utilization rate of the cleaning solvent.

[0021] Preferred Option 5: As a further optimization of Preferred Option 4, both the upper and lower molds of the mold are provided with temperature measuring holes. In step (2), after the mold is installed in the thermoforming machine, a temperature measuring coupler is inserted into the temperature measuring hole.

[0022] Preferred Option Six: As a further optimization of Preferred Option Five, the diameter of the temperature measuring hole is 5-7mm, the depth of the temperature measuring hole is 25-35mm, and the distance from the center of the temperature measuring hole to the mold surface is 12-17mm; so as to obtain the internal temperature of the mold more accurately.

[0023] Preferred Scheme 7: As a further optimization of Preferred Scheme 6, in step (5) during the preheating of the TA32 titanium alloy blank, the TA32 titanium alloy blank is placed between the upper mold and the lower mold and the upper mold presses down on the blank.

[0024] Preferred Option 8: As a further preference to Preferred Option 7, during steps 4-6, the temperature of the thermocouple is controlled below 816℃.

[0025] Preferred Option Nine: As a further optimization of Preferred Option Eight, in step (6), after the upper and lower molds are closed, a pressure of 10-15T is applied to the TA32 titanium alloy blank and it is kept warm. Attached Figure Description

[0026] Figure 1 Images of finished TA32 titanium alloy products processed using a specific process method described in the examples;

[0027] Figure 2 Images showing TA32 titanium alloy products broken due to conventional processing methods;

[0028] Figure 3 : A schematic diagram of the mold used in Example 6;

[0029] Figure 4 : Figure 3 Enlarged view of section A;

[0030] Figure 5 : Figure 3 Enlarged view of section B. Detailed Implementation

[0031] Example 1:

[0032] The hot creep forming process for titanium alloys includes the following steps:

[0033] Step 1: Clean the raw material and mold;

[0034] 1-1: Before cleaning the blank and mold, check the surface of the blank for scratches, dents or other defects. Those with defects cannot be used for processing.

[0035] 1-2: Use acetone as a cleaning solvent to clean the surface of TA32 titanium alloy blanks and molds; when cleaning, pour the solvent into a clean small container, then slowly pour the solvent from the small container onto a clean wiping cloth, wet the wiping cloth, wipe the surface of the parts with the wetted wiping cloth, and then wipe the wetted surface of the parts dry with a clean, dry wiping cloth.

[0036] 1-3: Visually inspect the surface of the parts. There should be no dust, corrosion, grease, oil stains, impurities, or other contaminants. Wipe the surface of the parts with a clean cloth. After the cloth is free of visible dirt, place the TA32 titanium alloy blank on a clean, neutral kraft paper.

[0037] Step 2: Install the mold;

[0038] 2-1: Install the upper and lower molds onto the thermoforming machine respectively;

[0039] After the mold is installed in the thermoforming machine, the mold can be tested to check whether the mold is installed in place. That is, in the cold state, the test mold blank is placed on the lower mold, the upper and lower molds are closed and pressure is maintained for a certain period of time, and then the test mold part is taken out. If the test mold part is qualified, the mold is installed in place.

[0040] 2-2: Insert thermocouples into the temperature measuring holes of the upper and lower molds respectively. The diameter of the temperature measuring hole is 6mm, the depth of the temperature measuring hole is 30mm, and the center of the temperature measuring hole is 15mm away from the surface of the mold.

[0041] Step 3: Apply lubricant;

[0042] A high-temperature lubricant is applied to the surface of the TA32 titanium alloy blank and the mold. The high-temperature lubricant can be boron nitride or yttrium oxide. In this embodiment, boron nitride is used as the high-temperature lubricant.

[0043] After the lubricant has dried, clean the lubricant and particles accumulated on the surface of the blank and mold.

[0044] Step 4: Heating the mold;

[0045] 4-1: Turn on the heating switch of the thermoforming machine to heat up the mold and control the mold temperature between 780-820℃;

[0046] 4-2: The mold temperature is monitored by a thermocouple inserted into the mold temperature measuring hole. In this embodiment, the thermoforming machine model is HT-R100A, and the temperature monitored by the thermocouple must not exceed 815℃.

[0047] Step 5: Preheat the billet;

[0048] 5-1: Raise the upper die, place the TA32 titanium alloy blank into the thermoforming machine and place it on the lower die, and lower the upper die to press down on the blank so that the blank produces a slight downward elastic deformation.

[0049] 5-2: Close the furnace door of the hot forming machine and preheat for 5 minutes. In this embodiment, the TA32 titanium alloy blank is a 1mm thick plate.

[0050] Step Six: Shaping;

[0051] 6-1: Close the upper and lower molds, apply a pressure of 10T to the upper mold and continue to hold the temperature for 10 minutes;

[0052] 6-2: Raise the upper mold and remove the formed part.

[0053] Example 2:

[0054] The difference between Example 2 and Example 1 is that the thermoforming machine in Example 2 is model HT-ER215.

[0055] In Example 2, during step four (mold heating), step five (bulk preheating), and step six (forming stage), the temperature monitored by the thermocouple must not exceed 816°C.

[0056] Example 3:

[0057] The difference between Example 3 and Example 1 is that the TA32 titanium alloy blank formed in Example 3 is a plate with a thickness of 1.5mm.

[0058] The main differences in the processing are in step five: billet preheating and step six: forming stage;

[0059] Step 5: Preheat the billet;

[0060] 5-1: Raise the upper mold, place the TA32 titanium alloy blank into the thermoforming machine and place it on the lower mold, and lower the upper mold to press down the blank;

[0061] 5-2: Close the oven door of the thermoforming machine and preheat for 8 minutes.

[0062] Step Six: Shaping;

[0063] 6-1: Close the upper and lower molds, apply a pressure of 12T to the upper mold and continue to hold the temperature for 12 minutes;

[0064] 6-2: Raise the upper mold and remove the formed part.

[0065] Example 4:

[0066] The difference between Example 4 and Example 1 is that the TA32 titanium alloy blank formed in Example 4 is a plate with a thickness of 2mm.

[0067] The main differences in the processing are in step five: billet preheating and step six: forming stage;

[0068] Step 5: Preheat the billet;

[0069] 5-1: Raise the upper mold, place the TA32 titanium alloy blank into the thermoforming machine and place it on the lower mold, and lower the upper mold to press down the blank;

[0070] 5-2: Close the oven door of the thermoforming machine and preheat for 12 minutes.

[0071] Step Six: Shaping;

[0072] 6-1: Close the upper and lower molds, apply a pressure of 15T to the upper mold and continue to hold the temperature for 15 minutes;

[0073] 6-2: Raise the upper mold and remove the formed part.

[0074] Example 6:

[0075] The difference between Example 6 and Example 1 lies in the further design of the mold used in Example 6. The mold body includes a lower mold 10, an upper mold 20, a blank holder 30, and a drive mechanism for driving the upper mold 20 and the blank holder 30. The opening of the thermoforming machine is located at the top, and both the upper mold 20 and the lower mold 10 enter the thermoforming machine through the top opening. The lower part of the drive mechanism is connected to the blank holder 30 and the lower mold 10, and the drive mechanism can drive the blank holder 30 and the upper mold 20 to enter the thermoforming machine through the opening; the upper part of the drive mechanism is located outside the thermoforming machine.

[0076] As attached Figure 3 , Figure 4 , Figure 5 As shown, the drive mechanism includes a drive column 41 fixed to the hydraulic press, a positioning part for positioning the pressure ring 30, and a power part for providing pressure to the pressure ring 30. The upper die 20 is fixed to the lower end of the drive column 41.

[0077] The power unit includes a cylinder 401 fixed to the upper part of the drive column 41, a piston column 402 slidably connected to the inner wall of the cylinder 401, and a sliding rod 403 slidably connected to the center of the piston column 402. The lower end of the sliding rod 403 passes through the pressure ring 30, and the upper end of the sliding rod 403 passes through the top of the piston column 402. The top of the sliding rod 403 is provided with an annular ridge to prevent the sliding column from sliding out of the piston column 402. When the annular ridge contacts the top of the piston column 402, the lower end of the sliding rod 403 extends out of the bottom of the pressure ring 30. The upper part of the cylinder 401 is provided with a hydraulic oil inlet. The hydraulic oil inlet is provided with a one-way valve 404 that can only allow liquid to enter the cylinder 401 to provide pressure to the inside of the cylinder 401.

[0078] The positioning part is used to limit the pressure ring 30 and the lower mold 10. The lower end of the piston column 402 is integrally formed with an annular connecting plate 42 surrounding the drive column 41. The annular connecting plate 42 is fixed to the pressure ring 30 by a screw connection. The positioning part consists of a limiting post 414 disposed in the annular connecting plate 42 and an ejection mechanism disposed in the drive column 41. The inner sidewall of the annular connecting plate 42 is provided with a blind hole arranged radially. The limiting post 414 is slidably connected in the blind hole and is provided with a first compression spring 416 to abut against the limiting post 414 so that the limiting post 414 can extend out of the blind hole. The end of the limiting post 414 facing the drive column 41 is set as a spherical surface. When the limiting post 414 extends out of the blind hole to the limit position, the cylindrical surface of the limiting post 414 intersects with the inner sidewall of the annular connecting plate 42.

[0079] The ejection mechanism is located in a radially arranged mounting hole on the drive column 41. When the blind hole is opposite to the mounting hole, the limiting column 414 will enter the mounting hole, thereby limiting the pressure ring 30 and the upper mold 20. At this time, the bottom surface of the pressure ring 30 is aligned with the lowest edge of the lower mold 10. The ejection mechanism includes a plug 411 slidably connected in the mounting hole, an ejector rod integrally formed with the plug 411 and pointing outward, and a second compression spring 413 sleeved on the ejector rod to press the plug 411 inward. A collar threaded to the side wall of the mounting hole is sleeved on the outer periphery of the ejector rod. The two ends of the second compression spring 413 press against the collar 412 and the plug 411, respectively.

[0080] The drive column 41 has a central oil passage 43 at its center. The lower end of the central oil passage 43 is connected to the mounting hole. Pressurizing the central oil passage 43 can drive the plug 411 to move outward and push the limiting column 414 outward. The top of the cylinder body 401 is connected to the relief valve 405. The relief oil passage 407 of the relief valve 405 is connected to the upper part of the central oil passage 43. Oil is supplied to the cylinder body 401 through the hydraulic oil inlet at a first pressure. The relief pressure of the relief valve 405 is a second pressure. The second pressure is greater than the first pressure. That is, when the pressure in the cylinder body 401 is greater than the second pressure, the relief valve 405 overflows. When the drive column 41 is lifted, the pressure ring 30 is positioned on the drive column 41, the cylinder body 401 maintains the first pressure, and the lower end of the sliding rod 403 extends from the pressure ring 30; when the drive column 41 moves downward with the third pressure (the third pressure is greater than the second pressure), the sliding rod 403 contacts the lower die 10 first, and the sliding rod 403 will move upward relative to the pressure ring 30 and enter the cylinder body 401. Then the hydraulic oil in the cylinder body 401 will overflow into the central oil passage 43 through the overflow valve 405, thereby increasing the pressure in the central oil passage 43 to push out the plug 411.

[0081] The mounting hole connects to the return oil passage 406, and the plug 411 can seal the return oil passage 406. As the plug 411 moves outward, the return oil passage 406 will connect with the mounting hole. When the plug 411 moves outward past the return oil passage 406, the spherical surface of the limiting post 414 is located on the inner side of the annular connecting plate 42. The overflow oil passage 407 connects to the return oil passage 406 through the branch pipe 408. An electric shut-off valve 409 is provided on the branch pipe 408, and a flow sensor 410 is provided in the overflow oil passage 407 to detect whether there is hydraulic oil passing through the overflow oil passage 407. The flow sensor 410 and the electric shut-off valve 409 are electrically connected to the input and output terminals of the controller, respectively. That is, when there is hydraulic oil passing through the overflow oil passage 407, the electric shut-off valve 409 is in the closed state, and when there is no liquid flow or only a trace flow in the overflow oil passage 407, the electric shut-off valve 409 is in the open state.

[0082] A control button is provided at the bottom of the blind hole. When the limiting post 414 is fully inserted into the blind hole, it will press the control button. When the control button is pressed, the drive post 41 stops moving downward. The power unit and the positioning unit are evenly arranged in three circumferential directions along the center line of the drive post 41 (the number varies depending on the shape of the mold).

[0083] A groove is provided on the lower die 10 corresponding to the lower end of the sliding rod 403. When the lower end of the sliding rod 403 presses on the blank, the groove will form a recessed groove on the blank to enhance the positioning effect.

[0084] Its specific working process is as follows:

[0085] (1) After the upper mold 20, lower mold 10 and pressure ring 30 are preheated, the upper mold 20 and pressure ring 30 are lifted by the drive column 41 and the blank is placed on the lower mold 10.

[0086] (2) The upper die 20 and the pressure ring 30 are driven downward by the drive column 41. After the pressure ring 30 fully contacts the blank (when the sliding rod 403 enters the cylinder 401 and reaches its limit position), the push rod pushes the limiting column 414 outward so that the spherical surface of the limiting column 414 is located on the inner side wall of the annular connecting plate. As the drive column 41 continues to move downward, the drive column 41 squeezes the spherical surface of the limiting column 414, pressing the limiting column 414 completely into the blind hole and squeezing the control switch 415. Thus, the control switch 415 controls the drive column 41 to stop moving, forming a pre-pressure on the blank.

[0087] (3) After the preheating of the billet is completed, the drive column 41 continues to move down to form the billet and hold the pressure.

[0088] (4) After the pressure holding is completed, the drive column 41 is raised. Under the pressure of the cylinder 401, the pressure ring 30 will continue to press on the lower mold 10, so that the drive column 41 and the pressure ring 30 form relative movement until the limit column 414 is aligned with the mounting hole. The limit column 414 will enter the mounting hole, thereby repositioning the pressure ring 30 and the upper mold 20, and the pressure ring 30 will also rise. Since the overflow valve 405 will not overflow during the rise of the drive column 41, the electric shut-off valve 409 is in the open state, and the plug 411 will be completely reset.

[0089] (5) Once the pressure ring 30 and the upper mold 20 are fully raised, the mold can be demolded.

[0090] This mold allows the upper mold to apply pressure to the blank, causing it to undergo elastic deformation, and then automatically stops, entering a preheating state. During the process of raising the upper mold, the pressure ring can be raised simultaneously to enable mass hot pressure forming.

[0091] Before the blank holder presses the blank, the sliding rod forms a recessed positioning point on the blank. After the blank holder enters the pressing state, the positioning points can further restrict the material extension of the pressing part in the forming state, so as to achieve a better pressing effect.

[0092] In addition, the lower end of the sliding rod can be connected to a pressure ring to connect the sliding rods of multiple power units into one piece; and the lower die is provided with an annular groove corresponding to the pressure ring. Thus, before the pressure ring presses the blank, the pressure ring forms a concave annular deformation on the blank. After the pressure ring enters the pressing state, the concave annular deformation can better restrict the material extension of the pressing part in the forming state, resulting in a better pressing effect.

[0093] The above descriptions are merely embodiments of the present invention, and common knowledge regarding specific structures and characteristics is not elaborated upon here. It should be noted that those skilled in the art can make various modifications and improvements without departing from the structure of the present invention, and these should also be considered within the scope of protection of the present invention. These modifications and improvements will not affect the effectiveness of the present invention or the practicality of the patent. The scope of protection claimed in this application should be determined by the content of its claims, and the specific embodiments described in the specification can be used to interpret the content of the claims.

Claims

1. A hot creep forming process for titanium alloys, characterized in that: Includes the following steps: (1) Clean the TA32 titanium alloy blank and mold surface with a thickness of 1mm, 1.5mm or 2mm using cleaning solvent until the surface is free of dust, corrosion, grease, impurities and other contaminants; (2) Install the mold onto the thermoforming machine; (3) Apply a high-temperature resistant lubricant to the surface of the TA32 titanium alloy blank and the mold; (4) Start the thermoforming machine to heat the mold and heat the mold to a temperature range of 780-820℃; (5) Place the TA32 titanium alloy blank into the hot forming machine and preheat for 5-12 minutes; (6) The upper and lower molds of the mold are closed to apply pressure to the preheated TA32 titanium alloy blank, and the part is removed after being kept under pressure for 10-15 minutes. In step (5), during the preheating of the TA32 titanium alloy blank, the TA32 titanium alloy blank is placed between the upper and lower molds and the upper mold presses down on the blank.

2. The hot creep forming process for titanium alloys according to claim 1, characterized in that: The cleaning solvent mentioned in step (1) is acetone or alcohol.

3. The hot creep forming process for titanium alloys according to claim 2, characterized in that: The high-temperature resistant lubricant mentioned in step (3) is boron nitride.

4. The hot creep forming process for titanium alloys according to claim 3, characterized in that: Step (1) When cleaning the TA32 titanium alloy blank and mold surface, slowly pour the cleaning solvent onto the wiping cloth to wet the cloth, and then wipe the blank and mold surface with the wiping cloth.

5. The hot creep forming process method for titanium alloys according to claim 4, characterized in that: In step (1), after cleaning the TA32 titanium alloy blank and mold surface with a cleaning solvent, the wetted part surface is wiped dry with a dry cloth.

6. The hot creep forming process method for titanium alloys according to claim 5, characterized in that: Temperature measuring holes are provided on both the upper and lower molds of the mold. In step (2), after the mold is installed with the thermoforming machine, a temperature measuring coupler is inserted into the temperature measuring hole.

7. The hot creep forming process for titanium alloys according to claim 6, characterized in that: The diameter of the temperature measuring hole is 5-7mm, the depth of the temperature measuring hole is 25-35mm, and the distance from the center of the temperature measuring hole to the surface is 12-17mm.

8. The hot creep forming process method for titanium alloys according to claim 7, characterized in that: During steps (4) to (6), the temperature of the thermocouple is controlled below 816℃.

9. The hot creep forming process method for titanium alloys according to claim 8, characterized in that: In step (6), after the upper and lower molds are closed, a pressure of 10-15T is applied to the TA32 titanium alloy blank and it is kept warm.

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