A manufacturing method for eliminating beta spots of a tb6 free forging

Abstract

The application relates to the field of non-ferrous metal material smelting, in particular to a manufacturing method of a TB6 free forging piece with eliminated beta spots, which comprises the following steps: proportioning alloy raw materials according to the mass percentage of elements; adopting a vacuum consumable furnace to perform three times of vacuum consumable smelting on the alloy raw materials; performing high-temperature homogenizing diffusion annealing treatment on a TB6 titanium alloy ingot to obtain an annealed TB6 titanium alloy ingot; performing cogging on the annealed titanium alloy ingot by a quick forging machine; performing heat preservation on the TB6 titanium alloy blank at a temperature of 990-1000 DEG C for 5-6 hours; and performing water cooling after the heat preservation to obtain a water-cooled TB6 titanium alloy blank; performing T β The following 40-50 DEG C is heat preserved for 3-4 hours, and then is forged into a material by a radial forging machine. The application effectively solves the problem of beta spots which are prone to occur in TB6 titanium alloy products; can effectively control Fe segregation, eliminate beta spot defects in the TB6 titanium alloy product organization, and improve the product yield.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of non-ferrous metal material smelting, and particularly relates to a manufacturing method of TB6 free forging eliminating beta spots. BACKGROUND

[0002] TB6 (Ti-10V-2Fe-3Al, American brand: Ti-1023) is a high-strength and high-toughness near-beta titanium alloy developed successfully by American Metal Corporation in the late 1970s. The alloy has the advantages of high specific strength, good fracture toughness, large hardening depth, small anisotropy, good forging performance and strong corrosion resistance, and has many advantages of metastable beta titanium alloy without losing the solid solution characteristics of alpha + beta titanium alloy, can meet the needs of damage tolerance design, high structural efficiency, high reliability and low cost, the maximum working temperature is 320 DEG C, and is mainly used for aircraft fuselage, wing and landing gear structure titanium alloy forgings, including beams, frames, nacelle joints, flap slides and the like.

[0003] However, since the alloy has a relatively high Fe content (2% Fe), since the distribution coefficient of Fe is 0.3, segregation is easily formed in the smelting and solidification process, and the organizational defects called "beta spots" are formed in the bar or forging product. When the fluctuation of the Fe content is 0.5%, the beta transition temperature changes by 42 DEG C, and the Fe element is a beta stabilizing element, which can reduce the phase transition point of the titanium alloy, if the Fe segregation exists in the TB6 ingot, the Fe-rich area will enter the beta phase zone in advance during the subsequent 40 DEG C to 50 DEG C hot working process, and the beta spot is formed. According to the area size, the maximum size and the number of the beta spot, the plasticity and the low-cycle fatigue of the material are affected to different degrees. How to control the Fe segregation and reduce or eliminate the number and size of the beta spot in the TB6 product organization has been a technical difficulty in the production of the material, which seriously limits the application and development of the TB6 titanium alloy product in the aviation field. Therefore, how to eliminate the "beta spot" of the TB6 titanium alloy product is a technical problem to be solved at the present stage. SUMMARY

[0004] In view of the above technical problems in the prior art, the present application provides a manufacturing method of TB6 free forging eliminating beta spots, which solves the technical problem that the TB6 free forging in the prior art is prone to segregation in the smelting and solidification process, and the organizational defects of "beta spots" are formed in the bar or forging product.

[0005] The present application provides a manufacturing method of TB6 free forging eliminating beta spots, comprising the following steps:

[0006] 1) according to the following mass percentage of elements, each alloy component is weighed, the prepared raw materials are mixed thoroughly, and then pressed into electrode blocks by a hydraulic press to obtain pressed consumable electrodes;

[0007] The alloy formula is as follows:

[0008]

[0009] The single mass percentage of impurities is ≤0.10%, and the total mass percentage of impurities is ≤0.30%;

[0010] 2) The pressed consumable electrodes are subjected to three vacuum consumable smelting by in-furnace welding in a vacuum consumable furnace to obtain TB6 titanium alloy ingots;

[0011] 3) The TB6 titanium alloy ingots are subjected to high-temperature homogenization diffusion annealing treatment to obtain annealed TB6 titanium alloy ingots;

[0012] 4) The annealed TB6 titanium alloy ingots are subjected to breakdown by a fast forging machine to obtain TB6 titanium alloy billets;

[0013] 5) The TB6 titanium alloy billets are subjected to heat preservation at a temperature of 990-1000℃ for 5-6 hours, and then subjected to water cooling to obtain water-cooled TB6 titanium alloy billets;

[0014] 6) The water-cooled TB6 titanium alloy billets are subjected to T β After the following 40-50℃ heat preservation for 3-4 hours, the billets are forged by a radial forging machine to obtain TB6 free forgings.

[0015] Further, in the above-mentioned TB6 free forging manufacturing method for eliminating β spots, the content of Fe element is 1.68wt%, 1.69wt% or 1.71wt%.

[0016] Further, in step 2), the first vacuum consumable smelting adopts current control mode, and the current is controlled at 10-12KA (which is beneficial to remove volatiles generated in the smelting process); the second and third smeltings adopt melting rate control mode, and the melting rate is controlled at 4.0Kg / min-4.5Kg / min to obtain TB6 titanium alloy ingots.

[0017] Further, in step 3), the TB6 titanium alloy ingots are first subjected to surface full peeling, and then high-temperature antioxidant paint is coated on the surface of the TB6 titanium alloy ingots;

[0018] Then, the TB6 titanium alloy ingots are subjected to high-temperature homogenization diffusion annealing treatment by a natural gas furnace to obtain annealed TB6 titanium alloy ingots;

[0019] The temperature of the high-temperature homogenization diffusion annealing is 1200-1250 DEG C, and the holding time is 20-24 hours.

[0020] Further, in step 4), the annealed titanium alloy ingot is opened by a fast forging machine, single-phase zone 2 times upsetting, two-phase zone 2 times upsetting, and then elongated to the required specification.

[0021] The single-phase zone forging temperature is greater than or equal to 1000 DEG C, the final forging temperature is greater than or equal to 850 DEG C, the single-phase zone deformation per heating is controlled in 30-40%, the two-phase zone forging temperature is greater than or equal to 730 DEG C, the final forging temperature is greater than or equal to 700 DEG C, and the two-phase zone deformation per heating is controlled in 50-60%.

[0022] The opening is to 200 square, and water cooling is performed after the forging is completed to obtain the TB6 titanium alloy blank.

[0023] Further, in step 5), single-phase zone 3 times upsetting, two-phase zone 3 times upsetting, and then elongation; opening to 380 square, water cooling after the forging is completed to obtain the water-cooled TB6 titanium alloy blank.

[0024] Further, in step 6), the open forging temperature is 720-740 DEG C, and the final forging temperature is greater than or equal to 700 DEG C.

[0025] Further, it further includes a process of checking beta spots, in which the TB6 free forging is heated to 775 DEG C and then water quenched, and then the beta spots are checked.

[0026] Further, it further includes a process of checking beta spots, in which the TB6 free forging is heated to 775 DEG C and then water quenched, and then the beta spots are checked. β The temperature of the following 25 DEG C is heated to water quenching, and the beta spots are checked.

[0027] The region without primary alpha phase or with few primary alpha phase appears in the titanium alloy structure, which is called beta spot. The beta spot in TB6 titanium alloy is not only related to the uneven chemical composition, but also related to the hot working process and mechanical heat treatment. In the present application, firstly, the low melting rate in the ingot smelting process is controlled to reduce the depth of the molten pool and thus reduce the segregation of Fe element; secondly, the Fe element is further diffused in the intracrystalline and intercrystalline through the high-temperature homogenization diffusion annealing of the ingot; and thirdly, the appearance of the beta spot can be inhibited through the reasonable design of the process parameters of the hot working process and the mechanical heat treatment, because the local region rich in Fe element is more likely to approach or even exceed the beta transition temperature, so the forging temperature far away from the phase transition point is selected when forging in the two-phase region, and water cooling is adopted after the end of forging, because the water cooling retains a large number of defects formed in the metal deformation process, and these dispersed crystal defects not only become the core of dynamic recrystallization in the subsequent hot working process, but also provide favorable conditions for the diffusion of Fe element due to the stored distortion energy. Therefore, by comprehensively using the manufacturing methods of smelting, hot working and mechanical heat treatment, the Fe segregation can be effectively controlled, and the beta spot defect in the free forging structure of TB6 titanium alloy can be eliminated.

[0028] Compared with the prior art, the technical effect of the present application is positive and obvious. The alloy composition is adjusted according to the standard of GJB2744A-2007, and then the alloy raw material is prepared, the electrode block is prepared by using the alloy raw material, and the consumable electrode is prepared after welding in the vacuum consumable furnace; the consumable electrode is subjected to three times of vacuum consumable smelting in the vacuum consumable furnace to obtain a TB6 titanium alloy ingot; the TB6 titanium alloy ingot is subjected to high-temperature homogenization diffusion annealing treatment to obtain an annealed TB6 titanium alloy ingot; the annealed titanium alloy ingot is subjected to breakdown by a quick forging machine to obtain a TB6 titanium alloy blank; the TB6 titanium alloy blank is subjected to heat preservation at a temperature of 990-1000 DEG C for 5-6 hours, and then subjected to water cooling after the heat preservation to obtain a water-cooled TB6 titanium alloy blank; the water-cooled TB6 titanium alloy blank is subjected to T β The TB6 free forging piece is obtained by radial forging machine forging after heat preservation at 40-50 DEG C for 3-4 hours. The problem of beta spot easily appearing in the TB6 titanium alloy product can be effectively solved; the Fe segregation can be effectively controlled, the beta spot defect in the TB6 titanium alloy product structure can be eliminated, and the yield of the product can be improved. BRIEF DESCRIPTION OF DRAWINGS

[0029] Various other advantages and benefits will become apparent to those of ordinary skill in the art upon reading the following detailed description of the preferred embodiments. The drawings are included only to illustrate preferred embodiments and are not to be considered as limiting of the application.

[0030] Figure 1 It is a schematic diagram of the structure of the TB6 free forging piece after heat treatment in the first embodiment of the present application.

[0031] Figure 2 schematic diagram of the heat-treated structure of the TB6 free forging in the second embodiment of the present application;

[0032] Figure 3 schematic diagram of the heat-treated structure of the TB6 free forging in the third embodiment of the present application. DETAILED DESCRIPTION

[0033] In order to make the objectives, technical solutions and advantages of the present application clearer, the present application will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and do not limit the present application.

[0034] Those skilled in the art can understand that, unless specifically stated otherwise, the singular forms "a", "an" and "the" used herein also include the plural forms. It should be further understood that the word "comprise" used in the specification of the present application means that the features, integers, steps, operations, elements and / or components exist, but does not exclude the existence or addition of one or more other features, integers, steps, operations, elements, components and / or groups thereof.

[0035] Embodiment 1

[0036] As shown in the schematic diagram of the heat-treated structure of the TB6 free forging in the first embodiment of the manufacturing method of the TB6 free forging for eliminating β spots in the embodiments of the present application, Figure 1 The TB6 free forging is prepared to be 100mm x 100mm x L mm (L is the length, the same below).

[0037] In step 101, each alloying component is weighed according to the mass percentage of the elements, and the prepared raw materials are fully mixed and then pressed into electrode blocks by a hydraulic press to obtain a pressed consumable electrode.

[0038] The alloy formula is as follows:

[0039] The mass percentage of Al is 2.94%,

[0040] The mass percentage of V is 10.39%,

[0041] The mass percentage of Fe is 1.71%,

[0042] The mass percentage of C is 0.01%,

[0043] The mass percentage of N is 0.008%,

[0044] The mass percentage of H is 0.0006%,

[0045] ​

[0046] The mass percentage of O is 0.08%,

[0047] Ti is the margin,

[0048] The mass percentage of a single impurity is ≤0.10%, and the total mass percentage of impurities is ≤0.30%.

[0049] Step 102: performing vacuum consumable melting on the alloy raw material three times in a vacuum consumable furnace to obtain a TB6 titanium alloy ingot;

[0050] Specifically, in this embodiment, the raw materials prepared in step 101 are pressed into an electrode block and welded in a vacuum consumable furnace. The vacuum consumable furnace is then used to perform vacuum consumable melting three times. The first vacuum consumable melting adopts a current control mode, with a current of 11.5 kA in the normal melting stage to remove volatile impurities generated during the melting process. The second vacuum consumable melting adopts a constant melting rate control mode with a melting rate set at 4.0 kg / min. The third vacuum consumable melting adopts the same melting rate control mode with a melting rate controlled at 4.5 kg / min. Finally, a φ580 mm TB6 titanium alloy ingot is obtained.

[0051] In this embodiment, the vacuum consumable furnace utilizes arc discharge to generate a high-temperature melting electrode in a vacuum environment, while the ingot is continuously solidified and increased in height in the crystallizer.

[0052] Step 103: performing high-temperature homogenization diffusion annealing treatment on the TB6 titanium alloy ingot to obtain an annealed TB6 titanium alloy ingot;

[0053] Specifically, in this embodiment, after the surface of the ingot obtained in step 102 is completely peeled, a high-temperature anti-oxidation coating is applied to the surface, and a high-temperature homogenization diffusion annealing treatment is performed in a natural gas furnace at a temperature of 1200° C.±10° C. for 21 hours.

[0054] In this embodiment, the high-temperature homogenization diffusion annealing treatment is: through high-temperature diffusion annealing, Fe atoms diffuse and eliminate microscopic segregation between dendrites.

[0055] In this embodiment, the high-temperature anti-oxidation coating is model KOT-1 (Hebei Lichen Anti-corrosion Coating Co., Ltd.), which is resistant to high temperatures and can effectively reduce the degree of surface oxidation of titanium alloy ingots at high temperatures.

[0056] Step 104: subjecting the annealed titanium alloy ingot to a rapid forging machine to form a TB6 titanium alloy billet;

[0057] Specifically, in this embodiment, the ingot processed in step 103 is opened in a fast forging machine, upset and drawn twice in the single-phase zone, upset and drawn twice in the two-phase zone, and then drawn to the required billet specifications, wherein the starting forging temperature of the single-phase zone is ≥1000°C, the final forging temperature is ≥850°C, and the deformation of each fire in the single-phase zone is controlled at 35%; the starting forging temperature of the two-phase zone is ≥730°C, the final forging temperature is ≥700°C, and the deformation of each fire in the two-phase zone is controlled at 55%. The billet is opened to 200 square meters and water-cooled after forging.

[0058] In this embodiment, the single-phase region is when the forging temperature is above the phase transformation point, and the alloy structure is entirely in the β phase region. The two-phase region is when the forging temperature is below the phase transformation point, and the alloy structure contains both α phase and β phase.

[0059] Step 105: keeping the TB6 titanium alloy blank at a temperature of 990° C.±10° C. for 5 hours, and then water-cooling the blank to obtain a water-cooled TB6 titanium alloy blank;

[0060] Specifically, in this embodiment, the blank obtained in step 104 is kept at 990° C.±10° C. for 5 hours and then water-cooled;

[0061] Step 106: The water-cooled TB6 titanium alloy blank is β After being kept at 40°C for 3 hours, the material was forged by a radial forging machine to obtain TB6 free forgings.

[0062] Specifically, in this embodiment, the material obtained in step 105 is subjected to T β After keeping the temperature below 40℃ for 3 hours, the product is forged into a forged product by a radial forging machine. The starting forging temperature is ≥730℃, the final forging temperature is ≥700℃, the elongation of each pass is ≤1.30, and the product is water-cooled after forging.

[0063] See also Figure 2 , schematic diagram of the microstructure of TB6 free forging after heat treatment in an embodiment of the present invention.

[0064] The TB6 free forgings made in this embodiment have a specification of 100mm×100mm×Lmm and are subjected to 775℃ or T β (phase transition point) and 25℃ below (the higher temperature of the two) and heat and quench in water, check for β spots, and the structure after heat treatment is as shown in the picture. Figure 1 As shown, upon inspection, no β-spot defects were found.

[0065] Example 2

[0066] like Figure 2 FIG. 1 is a schematic diagram of the microstructure of a TB6 free forging after heat treatment in a second embodiment of a method for manufacturing a TB6 free forging for eliminating β spots according to an embodiment of the present invention.

[0067] Prepare TB6 free forgings 300mm×300mm×Lmm;

[0068] Step 101: Weigh the alloy components according to the following mass percentages of the elements, fully mix the prepared raw materials, and press them into electrode blocks using a hydraulic press to obtain pressed consumable electrodes;

[0069] The alloy formula is as follows:

[0070] The mass percentage of Al is 2.89%,

[0071] The mass percentage of V is 10.38%,

[0072] The mass percentage of Fe is 1.68%,

[0073] The mass percentage of C is 0.01%,

[0074] The mass percentage of N is 0.008%,

[0075] The mass percentage of H is 0.0006%,

[0076] The mass percentage of O is 0.08%,

[0077] Ti is the margin,

[0078] The mass percentage of a single impurity is ≤0.10%, and the total mass percentage of impurities is ≤0.30%.

[0079] Step 2: After the raw materials prepared in step 1 are pressed into an electrode block and welded in a vacuum consumable furnace, vacuum consumable melting is performed three times in a vacuum consumable furnace. The first vacuum consumable melting adopts a current control mode, and the current in the normal melting stage is 11.0KA to remove volatile impurities generated during the melting process; the second vacuum consumable melting adopts a constant melting rate control mode, and the melting rate setting value is 4.1Kg / min; the third vacuum consumable melting adopts the same melting rate control mode, and the melting rate is controlled at 4.45Kg / min; finally, a φ580mmTB6 titanium alloy ingot is obtained;

[0080] In this embodiment, the vacuum consumable furnace utilizes arc discharge to generate a high-temperature melting electrode in a vacuum environment, while the ingot is continuously solidified and increased in height in the crystallizer.

[0081] Step 3: After the surface of the ingot obtained in step 2 is completely peeled, a high-temperature anti-oxidation coating is applied to the surface, and a high-temperature homogenization diffusion annealing treatment is performed in a natural gas furnace at a temperature of 1210°C ± 10°C for 22 hours;

[0082] In this embodiment, the high-temperature homogenization diffusion annealing treatment is: through high-temperature diffusion annealing, Fe atoms diffuse and eliminate microscopic segregation between dendrites.

[0083] In this embodiment, the high-temperature anti-oxidation coating is model KOT-1, which is resistant to high temperatures and can effectively reduce the degree of surface oxidation of titanium alloy ingots at high temperatures.

[0084] Step 4: The ingot processed in step 4 is blanked in a fast forging machine, and the single-phase region is upset and drawn three times, and the two-phase region is upset and drawn three times, and then drawn to the required billet specifications, wherein the starting forging temperature of the single-phase region is ≥1000°C, the final forging temperature is ≥850°C, and the deformation of each fire in the single-phase region is controlled at 36%; the starting forging temperature of the two-phase region is ≥730°C, the final forging temperature is ≥700°C, and the deformation of each fire in the two-phase region is controlled at 56%. The blank is blanked to 380 cubic meters and water-cooled after forging.

[0085] In this embodiment, the single-phase region is when the forging temperature is above the phase transformation point, and the alloy structure is entirely in the β phase region. The two-phase region is when the forging temperature is below the phase transformation point, and the alloy structure contains both α phase and β phase.

[0086] Step 5, the blank obtained in step 4 is kept at 995°C ± 10°C for 6 hours and then water-cooled;

[0087] Step 6: The material obtained in step 5 is subjected to T β After keeping the temperature at 45℃ below the phase transition point for 4 hours, the product is forged into a product by a radial forging machine. The starting forging temperature is ≥730℃, the final forging temperature is ≥700℃, the elongation of each pass is ≤1.30, and the product is water-cooled after forging.

[0088] The TB6 free forgings made in this embodiment have a size of 300mm×300mm×Lmm and are subjected to 775℃ or T β (phase transition point) and 25℃ below (the higher temperature of the two) and heat quench with water, check for β spots, and the microstructure after heat treatment is shown in the figure below. Figure 2 As shown, upon inspection, no β-spot defects were found.

[0089] Its beneficial effect is that it can effectively solve the problem of β spots that are prone to occur in TB6 titanium alloy products; it can effectively control Fe segregation, eliminate β spot defects in the finished TB6 titanium alloy product structure, and improve the yield rate of the product.

[0090] Example 3

[0091] like Figure 3 FIG. 1 is a schematic diagram of the microstructure of a TB6 free forging after heat treatment in a third embodiment of a method for manufacturing a TB6 free forging for eliminating β spots according to an embodiment of the present invention.

[0092] Prepare TB6 free forgings 320mm×320mm×Lmm;

[0093] Step 101: Weigh the alloy components according to the following mass percentages of the elements, fully mix the prepared raw materials, and press them into electrode blocks using a hydraulic press to obtain pressed consumable electrodes;

[0094] The alloy formula is as follows:

[0095] The mass percentage of Al is 2.91%,

[0096] The mass percentage of V is 10.37%,

[0097] The mass percentage of Fe is 1.69%,

[0098] The mass percentage of C is 0.01%,

[0099] The mass percentage of N is 0.008%,

[0100] The mass percentage of H is 0.0006%,

[0101] The mass percentage of O is 0.09%,

[0102] Ti is the balance,

[0103] The single mass percentage of impurities is ≤0.10%, and the total mass percentage of impurities is ≤0.30%.

[0104] Step 2, after the raw materials of the formula in step 1 are pressed into electrode blocks and welded in a vacuum consumable furnace, the electrode blocks are subjected to three times of vacuum consumable smelting in the vacuum consumable furnace. In the first time of vacuum consumable smelting, a current control mode is adopted, and the current in the normal smelting stage is 11.3 KA, so as to remove volatile impurities generated in the smelting process. In the second time, a constant melting rate control mode is adopted, and the melting rate setting value is 4.2 Kg / min. In the third time, a melting rate control mode is also adopted, and the melting rate is controlled at 4.46 Kg / min. Finally, a φ580 mm TB6 titanium alloy ingot is obtained.

[0105] In this embodiment, the vacuum consumable furnace is used to melt the electrode by high temperature generated by arc discharge in a vacuum environment, and the ingot is continuously solidified in the crystallizer.

[0106] Step 3, after the surface of the ingot obtained in step 2 is fully stripped, the surface is coated with high-temperature antioxidant paint, and high-temperature homogenization diffusion annealing treatment is carried out in a natural gas furnace, the temperature is 1240℃±10℃, and the holding time is 24h.

[0107] In this embodiment, the high-temperature homogenization diffusion annealing treatment is to eliminate the micro-segregation between dendrites by diffusion of Fe atoms through high-temperature diffusion annealing.

[0108] In this embodiment, the high-temperature antioxidant paint is KOT-1, which can effectively reduce the surface oxidation degree of the titanium alloy ingot at high temperature.

[0109] Step 4, the ingot treated in step 4 is broken down in a quick forging machine, and is upset and drawn 4 times in the single-phase zone and 4 times in the two-phase zone, wherein the open forging temperature in the single-phase zone is ≥1000℃, the final forging temperature is ≥850℃, and the deformation amount of each fire in the single-phase zone is controlled to be 38%; the open forging temperature in the two-phase zone is ≥730℃, the final forging temperature is ≥700℃, and the deformation amount of each fire in the two-phase zone is controlled to be 58%, and the breaking down is to 400 square, and the forging is water-cooled after the forging is finished;

[0110] In the embodiment, the single-phase zone is the forging temperature above the phase transition point, at which time the alloy structure is all in the β phase zone. The two-phase zone is the forging temperature below the phase transition point, at which time the alloy structure simultaneously exists in the α phase and the β phase.

[0111] Step 5, the blank obtained in step 4 is water-cooled after being kept at 1000℃±10℃ for 6 hours;

[0112] Step 6, the material obtained in step 5 is forged into a material by a T β (Phase transition point) below 50℃ for 4 hours, and is forged into a material by a radial forging machine, the open forging temperature is ≥730℃, the final forging temperature is ≥700℃, the elongation of each pass is ≤1.30, and the forging is water-cooled after the forging is finished.

[0113] The TB6 free forging piece prepared by the embodiment has a specification of 320mm×320mm×Lmm, and is heated at 775℃ or T β (Phase transition point) below 25℃ (the higher temperature of the two) and is water-quenched, the β spot is checked, and the microstructure picture after the heat treatment is shown in Figure 3 It is found that there is no β spot defect.

[0114] The beneficial effects are that the β spot problem easily occurring in the TB6 titanium alloy product can be effectively solved, the Fe segregation can be effectively controlled, the β spot defect in the finished product microstructure of the TB6 titanium alloy is eliminated, and the yield of the product is improved.

[0115] The basic principles, main features and advantages of the present application are shown and described above. The skilled in the art should understand the above, the present application is not limited by the above examples, the above examples and the description described in the specification are only preferred examples of the present application, and are not used to limit the present application, without departing from the spirit and scope of the present application, the present application will have various changes and improvements, and these changes and improvements all fall within the scope of the present application. The scope of protection of the present application is defined by the appended claims and their equivalents.

Claims

1. A method for manufacturing TB6 free forgings with β-spots eliminated, characterized in that: The following steps are involved: 1) Weigh the alloy components according to the following mass percentages of the elements, fully mix the prepared raw materials, and press them into electrode blocks using a hydraulic press to obtain pressed consumable electrodes; The alloy formula is as follows: Al 2.8%-3.2%， V 9.5%-10.5%， Fe 1.65%-1.72%, C ≤0.02%， N ≤0.01%， H ≤0.001%， O ≤0.10%， Ti is the balance, the mass percentage of a single impurity is ≤0.10%, and the total mass percentage of impurities is ≤0.30%; 2) welding the pressed consumable electrode in a vacuum consumable furnace and then performing vacuum consumable melting three times to obtain a TB6 titanium alloy ingot; the first vacuum consumable melting adopts a current control mode, and the current is controlled at 10-12 kA; ​​the second and third melting adopts a melting rate control mode, and the melting rate is controlled at 4.0 kg / min-4.5 kg / min, to obtain a TB6 titanium alloy ingot; 3) performing a high-temperature homogenization diffusion annealing treatment on the TB6 titanium alloy ingot to obtain an annealed TB6 titanium alloy ingot; the high-temperature homogenization diffusion annealing temperature is 1200-1250° C., and the holding time is 20-24 hours; 4) The annealed TB6 titanium alloy ingot is forged by a rapid forging machine, upsetting and drawing the single-phase region twice, upsetting and drawing the two-phase region twice, and then drawn to the required specifications; The starting forging temperature of the single-phase zone is ≥1000℃, the final forging temperature is ≥850℃, and the deformation of each fire in the single-phase zone is controlled at 30-40%; the starting forging temperature of the two-phase zone is ≥730℃, the final forging temperature is ≥700℃, and the deformation of each fire in the two-phase zone is controlled at 50-60%; the blank is opened to 200 cubic meters, and water-cooled after forging to obtain TB6 titanium alloy blank; 5) keeping the TB6 titanium alloy blank at a temperature of 990-1000° C. for 5-6 hours, and then water-cooling the blank to obtain a water-cooled TB6 titanium alloy blank; 6) The water-cooled TB6 titanium alloy billet is subjected to T β After being kept at 40-50°C for 3-4 hours, the material is forged by a radial forging machine to obtain TB6 free forgings.

2. The method for manufacturing a TB6 free forging with β-spot eliminated according to claim 1, characterized in that: The Fe element content is 1.68wt%, 1.69wt% or 1.71wt%.

3. The method for manufacturing a TB6 free forging with β-spot eliminated according to claim 1, characterized in that: In step 3), the surface of the TB6 titanium alloy ingot is first fully peeled, and then a high-temperature anti-oxidation coating is applied to the surface of the TB6 titanium alloy ingot; Then, a natural gas furnace is used to perform high-temperature homogenization diffusion annealing treatment on the TB6 titanium alloy ingot to obtain an annealed TB6 titanium alloy ingot.

4. The method for manufacturing a TB6 free forging with β-spot eliminated according to claim 1, wherein: In step 5), the single-phase region is upset and drawn three times, the two-phase region is upset and drawn three times, and then drawn to length; the blank is opened to 380 square meters, and water-cooled after forging to obtain a water-cooled TB6 titanium alloy blank.

5. The method for manufacturing a TB6 free forging with β-spot eliminated according to claim 1, characterized in that: In step 6), the starting forging temperature is 720-740°C and the final forging temperature is ≥700°C.

6. The method for manufacturing a TB6 free forging with β-spot eliminated according to claim 1, characterized in that: The method further includes a process for inspecting β spots. During the process, the TB6 free forging is heated to 775° C. and water quenched, and then the β spots are inspected.

7. The method for manufacturing a TB6 free forging with β-spot eliminated according to claim 1, characterized in that: The invention also includes a process of checking β spots. In the process of checking β spots, the TB6 free forging is subjected to T β After heating and quenching at a temperature below 25°C, check for β spots.

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