A method of forging a titanium alloy plate

Abstract

The application discloses a forging method of a titanium alloy plate, and comprises the following steps: S10, according to the size of a target forging, adopting multiple re-forging steps to re-forging a forging blank to obtain a re-forging forging; in each re-forging step, parameters are selected according to a re-forging temperature-re-forging deformation amount pairing table; S20, adopting multiple forming steps to perform forming treatment on the re-forging forging to obtain a formed forging; in each forming step, parameters are selected according to a forming temperature-forming deformation amount pairing table; S30, after performing shaping treatment and heat treatment on the formed forging, a target forging is obtained. The method provided by the application improves the first yield rate and internal organization performance of the obtained target forging by parameter pairing control in the forging process.

Description

Technical Field

[0001] This invention belongs to the field of titanium alloy hot working technology, and specifically relates to a forging method for titanium alloy plates. Background Technology

[0002] Titanium alloy sheet material is an alloy composed of three elements: titanium (Ti), aluminum (Al), and vanadium (V). It possesses excellent comprehensive properties, belonging to the (a+β) type alloy, and exhibits good overall mechanical properties. Titanium alloys have high specific strength; for example, TC4 (also known as Ti-6Al-4V) has a strength sb = 1.012 GPa, a density g = 4.51 g / cm³, and a specific strength sb / g = 23.5, while the specific strength sb / g of alloy steel is less than 18. Titanium alloys have low thermal conductivity; their thermal conductivity is 1 / 5 that of iron and 1 / 10 that of aluminum, with TC4 having a thermal conductivity of 7.955 W / mK. Therefore, titanium alloys possess high strength, heat resistance, and corrosion resistance, making them suitable for parts that operate continuously below 400℃.

[0003] Titanium alloy sheets are widely used in various fields due to their excellent properties such as high strength, low density, corrosion resistance, and high temperature resistance. In the aerospace industry, they are used for aircraft structural components, such as wings, fuselage frames, and landing gear; in the automotive industry, they are used for body frames, doors, engine valves, connecting rods, and suspension system components; in the medical field, they are used to manufacture artificial joints, bone plates, and screws; in the chemical industry, they are used in reaction vessels; and in the electronics industry, they are used to manufacture the casings of electronic devices such as mobile phones and laptops.

[0004] The conventional forging method for titanium alloy sheet forgings involves forging according to the dimensions of the forging, but there are very few requirements for controlling the forging process. Conventional forming forging also results in limited research on the internal microstructure and properties of the final forging. Ensuring that the internal microstructure and properties of the forging meet the required standards after forging and heat treatment is crucial for the production of titanium alloy sheet products.

[0005] It should be noted that the information disclosed in the background section above is only used to enhance the understanding of the background of the present invention, and therefore may include information that does not constitute prior art known to those skilled in the art. Summary of the Invention

[0006] To address the aforementioned problems in the prior art, this invention provides a forging method for titanium alloy plates. The technical problem to be solved by this invention is achieved through the following technical solution:

[0007] This invention provides a forging method for titanium alloy plates, comprising the following steps:

[0008] S10. Based on the dimensions of the target forging, multiple forging steps are used to forge the forging billet to obtain the forged forging.

[0009] In each forging step, the matching forging temperature and forging deformation amount are selected according to the matching table of forging temperature and forging deformation amount. The matching table of forging temperature and forging deformation amount includes 4 parameter pairs.

[0010] In the matching table of forging temperature and forging deformation:

[0011] The first parameter pair includes the forging temperature T1 and the forging deformation amount D1, wherein 1080℃<T1≤1150℃, and 40%<D1≤45%;

[0012] The second parameter pair includes the forging temperature T2 and the forging deformation amount D2, wherein 1030℃<T2≤1080℃, and 35%<D2≤40%;

[0013] The third parameter pair includes the forging temperature T3 and the forging deformation D3, wherein 960℃<T3≤1030℃, and 30%<D3≤35%;

[0014] The fourth parameter pair includes the forging temperature T4 and the forging deformation D4, wherein 940℃<T4≤960℃, and 25%≤D4≤30%;

[0015] S20. The modified forging is formed by multiple forming steps to obtain a shaped forging;

[0016] In each molding step, the matching molding temperature and molding deformation amount are selected according to the molding temperature-molding deformation amount pairing table, which includes 4 parameter pairs.

[0017] In the matching table of molding temperature and molding deformation:

[0018] The first parameter pair includes molding temperature t1 and molding deformation amount d1, wherein β-35℃<t1≤β-30℃, and 30%<d1≤35%;

[0019] The second parameter pair includes molding temperature t2 and molding deformation amount d2, where β-40℃<t2≤β-35℃, 25%<d2≤30%;

[0020] The third parameter pair includes molding temperature t3 and molding deformation d3, where β-45℃<t3≤β-40℃, and 20%<d3≤25%.

[0021] The fourth parameter pair includes molding temperature t4 and molding deformation amount d4, where β-50℃<t4≤β-45℃, 15%≤d4≤20%;

[0022] S30. After shaping and heat treatment of the formed forging, the target forging is obtained.

[0023] In one embodiment of the present invention, step S10 further includes selecting a matching forging temperature and forging cooling method in each forging step according to a matching table of forging temperature and forging cooling method, wherein the matching table of forging temperature and forging cooling method includes 4 parameter pairs.

[0024] In the matching table of forging temperature and forging cooling method:

[0025] The first parameter pair includes the forging temperature T1 and the forging cooling method C1, where 1080℃<T1≤1150℃ and C1 is air cooling;

[0026] The second parameter includes the forging temperature T2 and the forging cooling method C2, where 1030℃<T2≤1080℃ and C2 is air cooling;

[0027] The third parameter includes the forging temperature T3 and the forging cooling method C3, where 960℃<T3≤1030℃ and C3 is water cooling;

[0028] The fourth parameter pair includes the forging temperature T4 and the forging cooling method C4, where 940℃<T4≤960℃ and C4 is air cooling.

[0029] In one embodiment of the present invention, step S10 further includes selecting a matching forging temperature and forging thermal effect control time in each forging step according to a matching table of forging temperature and forging thermal effect control time. The matching table of forging temperature and forging thermal effect control time includes 4 parameter pairs.

[0030] In the pairing table of forging temperature and forging thermal effect control time:

[0031] The first parameter pair includes the forging temperature T1 and the forging thermal effect control time CT1, where 1080℃<T1≤1150℃ and 0.5s≤CT1<1.0s;

[0032] The second parameter pair includes the forging temperature T2 and the forging thermal effect control time CT2, wherein 1030℃<T2≤1080℃, 1.0s≤CT2<1.5s;

[0033] The third parameter pair includes the forging temperature T3 and the forging thermal effect control time CT3, where 960℃<T3≤1030℃ and 1.5s≤CT3<2.0s;

[0034] The fourth parameter pair includes the forging temperature T4 and the forging thermal effect control time CT4, where 940℃<T4≤960℃ and 2.0s≤CT4<2.5s.

[0035] In one embodiment of the present invention, step S20 further includes selecting a matching molding temperature and molding cooling method in each molding step according to a molding temperature-molding cooling method pairing table, wherein the molding temperature-molding cooling method pairing table includes 4 parameter pairs.

[0036] In the pairing table of molding temperature and molding cooling method:

[0037] The first parameter pair includes molding temperature t1 and molding cooling method c1, where β-35℃<t1≤β-30℃, and c1 is air cooling;

[0038] The second parameter pair includes molding temperature t2 and molding cooling method c2, where β-40℃<t2≤β-35℃, and c2 is air cooling;

[0039] The third parameter pair includes molding temperature t3 and molding cooling method c3, where β-45℃<t3≤β-40℃, and c3 is air cooling;

[0040] The fourth parameter pair includes molding temperature t4 and molding cooling method c4, where β-50℃<t4≤β-45℃ and c4 is air cooling.

[0041] In one embodiment of the present invention, step S20 further includes selecting a matching molding temperature and molding heat effect control time in each molding step according to a matching table of molding temperature and molding heat effect control time, wherein the matching table of molding temperature and molding heat effect control time includes 4 parameter pairs.

[0042] In the pairing table of molding temperature and molding heat effect control time:

[0043] The first parameter pair includes molding temperature t1 and molding thermal effect control time ct1, where β-35℃<t1≤β-30℃, 1.0s≤ct1<1.5s;

[0044] The second parameter pair includes molding temperature t2 and molding thermal effect control time ct2, where β-40℃<t2≤β-35℃, 1.5s≤ct2<2.0s;

[0045] The third parameter pair includes molding temperature t3 and molding thermal effect control time ct3, where β-45℃<t3≤β-40℃, 2.0s≤ct3<2.5s;

[0046] The fourth parameter pair includes molding temperature t4 and molding thermal effect control time ct4, where β-50℃<t4≤β-45℃ and 2.5s≤ct4<3.0s.

[0047] In one embodiment of the present invention, step S30 includes sandblasting and polishing.

[0048] In one embodiment of the present invention, in step S30, the heat treatment sequentially includes solution treatment, cooling treatment and aging treatment.

[0049] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0050] 1. The forging method for titanium alloy plates provided by the present invention controls the forging technical parameters of titanium alloy by designing matching parameters that are matched with the forging temperature and the forming temperature in the forging and forming steps, thereby improving the first-pass yield of forgings and reducing the probability of rework and scrap; at the same time, it improves the microstructure and property margin of the obtained forgings.

[0051] 2. This invention controls key parameters in titanium alloy forging by setting up matching tables for forging temperature and forging deformation, forging temperature and forging cooling method, forging temperature and forging thermal effect control time, and forming temperature and forming deformation, forming temperature and forming cooling method, and forming temperature and forming thermal effect control time. This ensures that the obtained forgings meet the final performance and internal structure requirements, reduces scrap rate, improves economic efficiency, and provides a new approach to titanium alloy forging technology.

[0052] 3. By using the parameter pairing control provided by this invention to control the forging process, for the same target forging, the performance of the obtained target forging can be improved or even reduced without decreasing the forging steps and / or forming steps.

[0053] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Attached Figure Description

[0054] Figure 1 This is a side view of the target forging obtained by the forging method of titanium alloy plate provided in the embodiment of the present invention;

[0055] Figure 2 This is a schematic diagram of the end face of the target forging obtained by the forging method of titanium alloy plate provided in the embodiment of the present invention;

[0056] Figure 3 This is an optical microscope characterization image of the target forging obtained by the forging method of titanium alloy plate provided in the embodiments of the present invention;

[0057] Figure 4 These are optical microscope images of commercially available forgings. Detailed Implementation

[0058] To further illustrate the technical means and effects adopted by the present invention to achieve the intended purpose, the following describes in detail a forging method for titanium alloy plates according to the present invention, in conjunction with the accompanying drawings and specific embodiments.

[0059] The foregoing and other technical contents, features, and effects of the present invention will be clearly presented in the following detailed description of specific embodiments in conjunction with the accompanying drawings. Through the description of the specific embodiments, a more in-depth and concrete understanding can be gained of the technical means and effects adopted by the present invention to achieve its intended purpose. However, the accompanying drawings are for reference and illustration only and are not intended to limit the technical solutions of the present invention.

[0060] It should be noted that 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 indicated technical features. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified.

[0061] In this document, the terms “comprising,” “including,” or any other variations are intended to cover non-exclusive inclusion, such that an article or device that comprises a list of elements includes not only those elements but also other elements not expressly listed. Without further limitation, an element defined by the phrase “comprising one…” does not exclude the presence of other identical elements in the article or device that includes said element.

[0062] Conventional forging suffers from a lack of defined pairing techniques for relevant technical parameters during the forging process, resulting in inaccurate control requirements for these parameters. This leads to substandard physical and chemical testing and performance evaluation of the forgings, causing rework and scrapping. Furthermore, it is impossible to improve the yield rate of forgings by correlated pairing and control of forging parameters. To address these problems, this invention provides a forging method for titanium alloy plates, comprising steps S10-S30.

[0063] S10. Based on the dimensions of the target forging, multiple forging steps are used to forge the forging billet to obtain the forged forging.

[0064] Table 1. Pairing Table of Forging Temperature and Forging Deformation

[0065]

[0066] In each forging step, the selection of forging temperature and forging deformation amount satisfies the forging temperature-forging deformation amount pairing table, which includes 4 parameter pairs.

[0067] See Table 1 for the pairing table of forging temperature and forging deformation:

[0068] The first parameter pair includes the forging temperature T1 and the forging deformation amount D1, wherein 1080℃<T1≤1150℃, and 40%<D1≤45%;

[0069] The second parameter pair includes the forging temperature T2 and the forging deformation amount D2, wherein 1030℃<T2≤1080℃, and 35%<D2≤40%;

[0070] The third parameter pair includes the forging temperature T3 and the forging deformation D3, wherein 960℃<T3≤1030℃, and 30%<D3≤35%;

[0071] The fourth parameter pair includes the forging temperature T4 and the forging deformation amount D4, where 940℃<T4≤960℃ and 25%≤D4≤30%.

[0072] Table 2. Pairing Table of Forging Temperature and Forging Cooling Method

[0073]

[0074]

[0075] In each forging step, the selection of forging temperature and forging cooling method satisfies the forging temperature-forging cooling method pairing table, which includes 4 parameter pairs.

[0076] See Table 2 for the pairing of forging temperature and forging cooling method:

[0077] The first parameter pair includes the forging temperature T1 and the forging cooling method C1, where 1080℃<T1≤1150℃ and C1 is air cooling;

[0078] The second parameter includes the forging temperature T2 and the forging cooling method C2, where 1030℃<T2≤1080℃ and C2 is air cooling;

[0079] The third parameter includes the forging temperature T3 and the forging cooling method C3, where 960℃<T3≤1030℃ and C3 is water cooling;

[0080] The fourth parameter pair includes the forging temperature T4 and the forging cooling method C4, where 940℃<T4≤960℃ and C4 is air cooling.

[0081] For titanium alloy slabs undergoing hot working, water cooling is typically used. The slab enters a rapid water quenching zone within 10 seconds of completing the hot working process. Symmetrical manifold nozzles spray cooling water vertically, with a water temperature of 5–35°C, a water pressure of 0.1 MPa–0.3 MPa, and a spraying speed of 2000–5000 m / s. 3 The cooling rate can be adjusted within the range of 5–70 °C / s. This allows for the retention of more vacancies and defects, as well as the storage of deformation energy, resulting in a fine-grained structure and improved properties.

[0082] Table 3. Pairing table of forging temperature and forging thermal effect control time

[0083]

[0084] In each forging step, the selection of forging temperature and forging thermal effect control time satisfies the pairing table of forging temperature and forging thermal effect control time, which includes 4 parameter pairs.

[0085] See Table 3 for the pairing table of forging temperature and forging thermal effect control time:

[0086] The first parameter pair includes the forging temperature T1 and the forging thermal effect control time CT1, where 1080℃<T1≤1150℃ and 0.5s≤CT1<1.0s;

[0087] The second parameter pair includes the forging temperature T2 and the forging thermal effect control time CT2, wherein 1030℃<T2≤1080℃, 1.0s≤CT2<1.5s;

[0088] The third parameter pair includes the forging temperature T3 and the forging thermal effect control time CT3, where 960℃<T3≤1030℃ and 1.5s≤CT3<2.0s;

[0089] The fourth parameter pair includes the forging temperature T4 and the forging thermal effect control time CT4, where 940℃<T4≤960℃ and 2.0s≤CT4<2.5s.

[0090] The parameters in Tables 1-3 above are selected without any order of preference. Choose the appropriate parameter from the corresponding parameter pairs based on the dimensions of the target forging and the parameters of the forging steps. For example, when the reforging temperature is 1100℃, the reforging deformation can be 42%, air cooling can be selected as the reforging cooling method, and the reforging thermal effect control time can be 0.8s / hammer.

[0091] Furthermore, the number of reforging steps can be selected based on the target forging. Using the forging method provided by this invention, for the same target forging, the yield rate of forgings can be improved while reducing the number of reforging steps.

[0092] S20. The modified forging is formed by multiple forming steps to obtain a shaped forging.

[0093] Table 4. Pairing table of molding temperature and molding deformation.

[0094] Molding temperature β-35℃＜t1≤β-30℃ β-40℃＜t2≤β-35℃ β-45℃＜t3≤β-40℃ β-50℃＜t4≤β-45℃ Molding deformation 30％＜d1≤35％ 25％＜d2≤30％ 20％＜d3≤25％ 15％≤d4≤20％

[0095] In each molding step, the selection of molding temperature and molding deformation amount satisfies the molding temperature-molding deformation amount pairing table, which includes 4 parameter pairs.

[0096] See Table 4 for the pairing table of molding temperature and molding deformation:

[0097] The first parameter pair includes molding temperature t1 and molding deformation amount d1, wherein β-35℃<t1≤β-30℃, and 30%<d1≤35%;

[0098] The second parameter pair includes molding temperature t2 and molding deformation amount d2, where β-40℃<t2≤β-35℃, 25%<d2≤30%;

[0099] The third parameter pair includes molding temperature t3 and molding deformation d3, where β-45℃<t3≤β-40℃, and 20%<d3≤25%.

[0100] The fourth parameter pair includes molding temperature t4 and molding deformation amount d4, where β-50℃<t4≤β-45℃ and 15%≤d4≤20%.

[0101] Table 5. Pairing Table of Molding Temperature and Molding Cooling Method

[0102] Molding temperature β-35℃＜t1≤β-30℃ β-40℃＜t2≤β-35℃ β-45℃＜t3≤β-40℃ β-50℃＜t4≤β-45℃ Molding and cooling methods air cooling air cooling air cooling air cooling

[0103] In each molding step, the selection of molding temperature and molding cooling method satisfies the molding temperature-molding cooling method pairing table, which includes 4 parameter pairs.

[0104] See Table 5 for the pairing of molding temperature and molding cooling method:

[0105] The first parameter pair includes molding temperature t1 and molding cooling method c1, where β-35℃<t1≤β-30℃, and c1 is air cooling; the second parameter pair includes molding temperature t2 and molding cooling method c2, where β-40℃<t2≤β-35℃, and c2 is air cooling.

[0106] The third parameter pair includes molding temperature t3 and molding cooling method c3, where β-45℃<t3≤β-40℃, and c3 is air cooling;

[0107] The fourth parameter pair includes molding temperature t4 and molding cooling method c4, where β-50℃<t4≤β-45℃ and c4 is air cooling.

[0108] Table 6. Pairing Table of Molding Temperature and Molding Thermal Effect Control Time

[0109]

[0110] In each molding step, the selection of molding temperature and molding thermal effect control time satisfies the molding temperature-molding thermal effect control time pairing table, which includes 4 parameter pairs.

[0111] See Table 6 for the pairing table of molding temperature and molding heat effect control time:

[0112] The first parameter pair includes molding temperature t1 and molding thermal effect control time ct1, where β-35℃<t1≤β-30℃, 1.0s≤ct1<1.5s;

[0113] The second parameter pair includes molding temperature t2 and molding thermal effect control time ct2, where β-40℃<t2≤β-35℃, 1.5s≤ct2<2.0s;

[0114] The third parameter pair includes molding temperature t3 and molding thermal effect control time ct3, where β-45℃<t3≤β-40℃, 2.0s≤ct3<2.5s;

[0115] The fourth parameter pair includes molding temperature t4 and molding thermal effect control time ct4, where β-50℃<t4≤β-45℃ and 2.5s≤ct4<3.0s.

[0116] The parameters in Tables 4-6 above are not ranked in any particular order. Choose the appropriate parameter from the corresponding parameter pairs based on the dimensions of the target forging and the parameters of the forging steps. For example, when the forming temperature is β-38℃, the forming deformation can be 27%, air cooling can be selected as the forming cooling method, and the forming heat effect control time can be 1.6s / hammer.

[0117] Furthermore, the number of forming steps can be selected based on the target forging. Using the forging method provided by this invention, for the same target forging, the yield rate of forgings can be improved while reducing the number of forming steps.

[0118] S30. After shaping and heat treatment of the formed forging, the target forging is obtained.

[0119] For example, the forming process includes sandblasting and grinding. Sandblasting removes oxide scale (such as the α-case layer of titanium alloys), oil, and forging residues from the surface of the forging after the forming step, providing a uniform surface roughness for subsequent inspection or machining. Grinding removes burrs, flash, and minor surface defects (such as folds and cracks), and corrects dimensional deviations (such as localized protrusions).

[0120] For example, heat treatment sequentially includes solution treatment, cooling treatment, and aging treatment. Heat treatment can improve the strength of titanium alloy materials. During the heat treatment process, rapid cooling after solution treatment can form a metastable phase, and then aging treatment precipitates a strengthening phase.

[0121] The forging method of titanium alloy sheet provided by the present invention will be further described below with reference to specific embodiments.

[0122] In this embodiment, the forging billet used is Ti-6Al-4V, with dimensions of φ690mm × 1710mm and a weight of 2877.4Kg; there are 5 forging billets, numbered 001-005; the dimensions of the target forging are...

[0123] The equipment used in the forging process includes: an electric furnace for heating; and a 4500 hydraulic press for forging.

[0124] In this embodiment, the "maximum forging time" is the total time to complete the forging of 5 forgings in one process step; the "thermal effect control time" is the allowable time window for each hammer blow (or single deformation) of the forging, which is used to manage the temperature change and microstructure evolution of the forging during dynamic deformation.

[0125] The specific forging process includes the following steps:

[0126] S10. Based on the dimensions of the target forging, the forging process is divided into four reforging steps. These four reforging steps specifically include:

[0127] S101, First Forging Step

[0128] Heating: Preheat the electric furnace to a temperature of less than or equal to 800℃. Place the forging billet into the electric furnace and heat it to 850℃±50℃, hold for 120 minutes; then heat it to 1150℃±10℃ and hold for 360 minutes.

[0129] Forging: Forging parameters are based on a deformation of 43%, air cooling, and a heat effect control time of 0.6 s / hammer; the maximum forging time is less than or equal to 120 min.

[0130] Forging was carried out using the above forging parameters: before forging, the size of the forging billet was φ690mm×1710mm; after axial upsetting, the size became 900±5mm×900±5mm×790±5mm; after reversing the direction and drawing, the size of the forging after the first reforging was 650±5mm×650±5mm×1510±5mm.

[0131] S102, Second Forging Step

[0132] Heating: Preheat the electric furnace to a temperature of less than or equal to 800℃. Place the forging after the first forging into the electric furnace and heat it to 850℃±50℃, hold for 120 minutes; then heat it to 1080℃±10℃ and hold for 520 minutes.

[0133] Forging: Forging parameters are set at a deformation of 38%, air cooling, and a heat effect control time of 1.2 s / hammer; the maximum forging time is less than or equal to 120 min.

[0134] The forgings after the first forging were forged using the above forging parameters: after axial upsetting, the dimensions became 900±5mm×900±5mm×790±5mm; after reversing and drawing, the dimensions of the forgings after the second forging were 650±5mm×650±5mm×1510±5mm.

[0135] S103, Third Forging Step

[0136] Heating: Preheat the electric furnace to a temperature of less than or equal to 800℃. Place the forging after the second forging into the electric furnace and heat it to 850℃±50℃, hold for 120 minutes; then heat it to 1030℃±10℃ and hold for 520 minutes.

[0137] Forging: Forging parameters are based on a deformation of 33%, water cooling, and a heat effect control time of 1.7s / hammer; the maximum forging time is less than or equal to 120min.

[0138] The forging after the second forging was forged using the above forging parameters: after axial upsetting, the size became 900±5mm×900±5mm×790±5mm; after reversing and drawing, the size of the forging after the third forging was 650±5mm×650±5mm×1510±5mm.

[0139] S104, Fourth Forging Step

[0140] Heating: Preheat the electric furnace to a temperature of less than or equal to 800℃. Place the forging after the third forging into the electric furnace and heat it to 850℃±50℃, hold for 120 minutes; then heat it to 960℃±10℃ and hold for 520 minutes.

[0141] Forging: Forging parameters are set at a deformation of 28%, air cooling, and a heat effect control time of 2.3s / hammer; the maximum forging time is less than or equal to 120min.

[0142] The forging after the third forging was forged using the above forging parameters: after axial upsetting, the size became 900±5mm×900±5mm×790±5mm; after reversing and drawing, the size of the forging after the fourth forging was 650±5mm×650±5mm×1510±5mm.

[0143] S20. Based on the dimensions of the target forging, the forging process is divided into four forming steps. The four re-forging steps specifically include:

[0144] S201, First Molding Step

[0145] Heating: Preheat the electric furnace to a temperature less than or equal to 800℃. Place the forging after the fourth forging into the electric furnace and heat it to 850℃±50℃, holding for 120 min. Then heat it to β-30℃±10℃ and hold for 520 min. Here, β-30℃ represents the temperature point 30℃ lower than the β transformation temperature (Tβ), typically used to describe the hot working or heat treatment window of titanium alloys; the β transformation temperature (Tβ) represents the critical temperature at which the titanium alloy completely transforms from the α+β two-phase region to the β single-phase region.

[0146] Forging: Forging parameters are based on a deformation of 33%, air cooling, and a heat effect control time of 1.3s / hammer; the maximum forging time is less than or equal to 120min.

[0147] The forging after the fourth forging was forged using the above forging parameters: after axial forging, the first-formed forging was obtained, with dimensions of 1200±10mm × ~295mm × 1800±10mm. The height parameter is approximately 295mm, which can fluctuate within a certain range while still meeting the width (1200±10mm) and length (1800±10mm) requirements.

[0148] S202, Second molding step

[0149] Heating: Preheat the electric furnace to a temperature of less than or equal to 800℃. After the first forming, place the forging into the electric furnace and heat it to 850℃±50℃, hold for 120 minutes. Then heat it to β-35℃±10℃ and hold for 240 minutes.

[0150] Forging: Forging parameters are set at a deformation of 27%, air cooling, and a heat effect control time of 1.8s / hammer; the maximum forging time is less than or equal to 120min.

[0151] The forgings after the first forming are forged using the above forging parameters: after axial forging, a forging after the second forming is obtained. The dimensions of the forging after the second forming are 1400±10mm × ~195mm × 2300±10mm. Among them, the height parameter is approximately 195mm, which can fluctuate within a certain range while meeting the width (1400±10mm) and length (2300±10mm).

[0152] S203, Third Molding Step

[0153] Heating: Preheat the electric furnace to a temperature of less than or equal to 800℃. After the second forming, place the forging into the electric furnace and heat it to 850℃±50℃, hold for 120 minutes. Then heat it to β-40℃±10℃ and hold for 155 minutes.

[0154] Forging: Forging parameters are set at a deformation of 23%, air cooling, and a heat effect control time of 2.3 s / hammer; the maximum forging time is less than or equal to 120 min.

[0155] The forging after the second forming is forged using the above forging parameters: after axial forging, a forging after the third forming is obtained. The dimensions of the forging after the third forming are 1600±10mm × ~135mm × 2900±10mm. Among them, the height parameter is approximately 135mm, which can fluctuate within a certain range while meeting the width (1600±10mm) and length (2900±10mm).

[0156] S204, Fourth Molding Step

[0157] Heating: Preheat the electric furnace to a temperature of less than or equal to 800℃. After the first forming, place the forging into the electric furnace and heat it to 850℃±50℃, hold for 120 minutes. Then heat it to β-45℃±10℃ and hold for 110 minutes.

[0158] Forging: Forging parameters are set at a deformation rate of 17%, air cooling method, and a heat effect control time of 2.8s / hammer; the maximum forging time is less than or equal to 120min.

[0159] The forging after the third forming was forged using the above forging parameters: after axial forging, the forging after the fourth forming was obtained. The size of the forging after the fourth forming was 1800±7mm×110±3mm×3220±10mm.

[0160] S30. After forging, the forging undergoes sandblasting and grinding to achieve the desired dimensions.

[0161] S40. The forgings after shaping are heat-treated to obtain five target forgings, wherein the target forgings are plate-shaped structures, such as... Figure 1 and Figure 2 As shown.

[0162] Two of the target forgings obtained in the above embodiments (defined as target forging 1 and target forging 2) and commercially available plate forgings (defined as commercially available forging 1 and commercially available forging 2) were inspected using a high-magnification electron microscope. Figure 3 In the figure, (a) is a characterization diagram of target forging 1, and (b) is a characterization diagram of target forging 2; Figure 4 In the diagram, (a) and (c) are characterization diagrams of commercially available forging 1, and (b) and (d) are characterization diagrams of commercially available forging 2.

[0163] like Figure 3 and Figure 4 As shown, compared with commercially available plate forgings, the forging method provided by this invention produces forgings with smaller crystal grain size and higher crystal grain uniformity, which can give the forgings higher strength, plasticity and toughness.

[0164] The above description, in conjunction with specific preferred embodiments, provides a further detailed explanation of the present invention. It should not be construed that the specific implementation of the present invention is limited to these descriptions. For those skilled in the art, various simple deductions or substitutions can be made without departing from the concept of the present invention, and all such modifications and substitutions should be considered within the scope of protection of the present invention.

Claims

1. A forging method for titanium alloy plates, characterized in that, Includes the following steps: S10. Based on the dimensions of the target forging, multiple forging steps are used to forge the forging billet to obtain the forged forging. In each forging step, the matching forging temperature and forging deformation amount are selected according to the matching table of forging temperature and forging deformation amount. The matching table of forging temperature and forging deformation amount includes 4 parameter pairs. In the matching table of forging temperature and forging deformation: The first parameter pair includes the forging temperature T1 and the forging deformation amount D1, where 1080℃ < T1 ≤ 1150℃ and 40% < D1 ≤ 45%; the second parameter pair includes the forging temperature T2 and the forging deformation amount D2, where 1030℃ < T2 ≤ 1080℃ and 35% < D2 ≤ 40%; the third parameter pair includes the forging temperature T3 and the forging deformation amount D3, where 960℃ < T3 ≤ 1030℃ and 30% < D3 ≤ 35%; the fourth parameter pair includes the forging temperature T4 and the forging deformation amount D4, where 940℃ < T4 ≤ 960℃ and 25% ≤ D4 ≤ 30%. In each forging step, a matching forging temperature and forging cooling method are selected according to the forging temperature-forging cooling method pairing table, which includes 4 parameter pairs. In the matching table of forging temperature and forging cooling method: The first parameter pair includes the forging temperature T1 and the forging cooling method C1, where 1080℃ < T1 ≤ 1150℃, and C1 is air cooling; the second parameter pair includes the forging temperature T2 and the forging cooling method C2, where 1030℃ < T2 ≤ 1080℃, and C2 is air cooling; the third parameter pair includes the forging temperature T3 and the forging cooling method C3, where 960℃ < T3 ≤ 1030℃, and C3 is water cooling; the fourth parameter pair includes the forging temperature T4 and the forging cooling method C4, where 940℃ < T4 ≤ 960℃, and C4 is air cooling. In each forging step, according to the pairing table of forging temperature and forging thermal effect control time, the matching forging temperature and forging thermal effect control time are selected. The pairing table of forging temperature and forging thermal effect control time includes 4 parameter pairs. In the pairing table of forging temperature and forging thermal effect control time: The first parameter pair includes the forging temperature T1 and the forging thermal effect control time CT1, where 1080℃ < T1 ≤ 1150℃, and 0.5s ≤ CT1 < 1.0s; the second parameter pair includes the forging temperature T2 and the forging thermal effect control time CT2, where 1030℃ < T2 ≤ 1080℃, and 1.0s ≤ CT2 < 1.5s; the third parameter pair includes the forging temperature T3 and the forging thermal effect control time CT3, where 960℃ < T3 ≤ 1030℃, and 1.5s ≤ CT3 < 2.0s; the fourth parameter pair includes the forging temperature T4 and the forging thermal effect control time CT4, where 940℃ < T4 ≤ 960℃, and 2.0s ≤ CT4 < 2.5s. S20. The modified forging is formed by multiple forming steps to obtain a shaped forging; In each molding step, the matching molding temperature and molding deformation amount are selected according to the molding temperature-molding deformation amount pairing table, which includes 4 parameter pairs. In the matching table of molding temperature and molding deformation: The first parameter pair includes molding temperature t1 and molding deformation d1, where β-35℃<t1≤β-30℃, and 30%<d1≤35%; the second parameter pair includes molding temperature t2 and molding deformation d2, where β-40℃<t2≤β-35℃, and 25%<d2≤30%; the third parameter pair includes molding temperature t3 and molding deformation d3, where β-45℃<t3≤β-40℃, and 20%<d3≤25%; the fourth parameter pair includes molding temperature t4 and molding deformation d4, where β-50℃<t4≤β-45℃, and 15%≤d4≤20%. In each molding step, a matching molding temperature and molding cooling method are selected according to the molding temperature-molding cooling method pairing table, which includes 4 parameter pairs. In the pairing table of molding temperature and molding cooling method: The first parameter pair includes molding temperature t1 and molding cooling method c1, where β-35℃<t1≤β-30℃, and c1 is air cooling; the second parameter pair includes molding temperature t2 and molding cooling method c2, where β-40℃<t2≤β-35℃, and c2 is air cooling; the third parameter pair includes molding temperature t3 and molding cooling method c3, where β-45℃<t3≤β-40℃, and c3 is air cooling; the fourth parameter pair includes molding temperature t4 and molding cooling method c4, where β-50℃<t4≤β-45℃, and c4 is air cooling. In each molding step, according to the matching table of molding temperature and molding heat effect control time, the matching molding temperature and molding heat effect control time are selected. The matching table of molding temperature and molding heat effect control time includes 4 parameter pairs. In the pairing table of molding temperature and molding heat effect control time: The first parameter pair includes molding temperature t1 and molding heat effect control time ct1, where β-35℃<t1≤β-30℃, 1.0s≤ct1<1.5s; the second parameter pair includes molding temperature t2 and molding heat effect control time ct2, where β-40℃<t2≤β-35℃, 1.5s≤ct2<2.0s; the third parameter pair includes molding temperature t3 and molding heat effect control time ct3, where β-45℃<t3≤β-40℃, 2.0s≤ct3<2.5s; the fourth parameter pair includes molding temperature t4 and molding heat effect control time ct4, where β-50℃<t4≤β-45℃, 2.5s≤ct4<3.0s; S30. After shaping and heat treatment of the formed forging, the target forging is obtained.

2. The forging method for titanium alloy plates according to claim 1, characterized in that, In step S30, the shaping process includes sandblasting and polishing.

3. The forging method for titanium alloy plates according to claim 2, characterized in that, In step S30, the heat treatment sequentially includes solution treatment, cooling treatment, and aging treatment.

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