Preparation method of TA15 titanium alloy sheet

Abstract

The invention provides a preparation method of a TA15 titanium alloy thin plate, which comprises the following steps: S1, carrying out initial rolling on a TA15 titanium alloy plate blank with the thickness of 150mm under the conditions that the initial rolling temperature is 10-30 DEG C above a beta phase transformation point and the final rolling temperature is not lower than 800 DEG C to obtain a primary semi-finished plate with the thickness of 12-18mm; s2, the primary semi-finished plate in the step S1 is subjected to width cutting and homogenization treatment; and S3, carrying out secondary rolling on the primary semi-finished plate in the step S2 under the conditions that the initial rolling temperature is 50-90 DEG C below the beta phase transformation point and the final rolling temperature is not lower than 800 DEG C. According to the preparation method of the TA15 titanium alloy thin plate, the structure and performance of the TA15 thin plate are regulated and controlled by controlling rolling process parameters such as the rolling deformation after width cutting and the rolling heating temperature of the finished product, and reduction of the room-temperature mechanical property of the plate is facilitated through reduction of the rolling deformation after width cutting and increase of the rolling heating temperature of the finished product; the mechanical property stability is improved.

Description

Technical Field

[0001] The invention relates to the technical field of metal material processing, and in particular to a method for preparing a TA15 titanium alloy thin plate. Background Art

[0002] The nominal chemical composition of TA15 titanium alloy is Ti-6.5Al-1Mo-1V-2Zr. Solid solution strengthening of α-stabilizing element Al is the main strengthening mechanism of TA15 titanium alloy. Neutral element Zr and β-stabilizing elements Mo and V are added to TA15 titanium alloy to improve processability. Its Al equivalent is 6.58% and Mo equivalent is 2.46%. It belongs to a nearly α-type titanium alloy with high Al equivalent. It has both good thermal strength and weldability of α-type titanium alloy and process plasticity close to α-β-type titanium alloy. It has higher strength and better welding performance than TC4 titanium alloy. The alloy can work at a long-term working temperature of 500℃ and an instantaneous working temperature of 800℃. When working at 450℃, its service life can reach 6000h.

[0003] With the development of my country's aerospace industry, TA15 titanium alloy sheets are used as raw materials for various parts of aircraft engines. At the same time, with the steady improvement of various performances of aerospace launch equipment, higher requirements are placed on the performance stability of TA15 titanium alloy sheets for aerospace use.

[0004] At present, TA15 thin plates are mainly produced in sheet form, with slabs as raw materials, and are rolled to a thickness suitable for cold rolling production through multiple hot rolling processes; finished product rolling uses the semi-finished titanium plates rolled out by the above hot rolling as incoming materials, and is rolled to the finished product thickness through cold rolling, and then undergoes heat treatment and surface treatment to produce qualified finished products. The TA15 titanium alloy thin plates produced by the existing processing methods have a relatively high room temperature tensile strength while meeting the high temperature endurance performance of 50 hours without breaking, and the margin from the upper limit of the technical requirements is relatively small.

[0005] Therefore, it is necessary to provide a method for preparing TA15 titanium alloy thin plate to solve the above technical problems. Summary of the invention

[0006] The present invention provides a method for preparing a TA15 titanium alloy thin plate, which solves the problem of high room temperature tensile strength and small margin from the upper limit of technical requirements while ensuring that the high temperature endurance performance of the TA15 titanium alloy thin plate meets the requirement of not breaking for 50 hours.

[0007] In order to solve the above technical problems, the present invention provides a method for preparing a TA15 titanium alloy thin plate, comprising the following steps:

[0008] S1. Initially rolling a TA15 titanium alloy slab with a thickness of 150 mm at an initial rolling temperature of 10°C to 30°C above the β phase transformation point and a final rolling temperature of not less than 800°C to obtain a semi-finished plate with a thickness of 12 to 18 mm;

[0009] S2, cutting the semi-finished plate in step S1 into a uniform size;

[0010] S3, performing secondary rolling on the semi-finished plate in step S2 at an initial rolling temperature of 50°C to 90°C below the β phase transformation point and a final rolling temperature of not less than 800°C, and performing surface grinding treatment after air cooling to obtain a secondary semi-finished plate with a thickness of 6mm to 8mm;

[0011] S4, rolling the secondary semi-finished plate in step S3 for three times at an initial rolling temperature of 50°C to 90°C below the β phase transformation point and a final rolling temperature of not less than 800°C, and performing surface grinding after air cooling to obtain a tertiary semi-finished plate with a thickness of 4 mm;

[0012] S5, rolling the three-time semi-finished plate in step S4 for four times, and then performing surface grinding treatment to obtain a four-time semi-finished plate with a thickness of 3.5 mm;

[0013] S6, rolling the four semi-finished plates in step S5 at an initial rolling temperature of 880°C to 900°C and a final rolling temperature of not less than 800°C, and then performing surface grinding treatment to obtain a finished plate with a thickness of 1.0 mm;

[0014] S7, annealing the finished plate in step S6 by heat treatment system of keeping the temperature at 820°C to 880°C for 1 hour and then air cooling, and then performing surface treatment to obtain a finished plate that meets the technical requirements.

[0015] Preferably, the width cutting in step S2 is to cut the plate to a certain length, rotate it 90 degrees for the next rolling, and the width of the plate is the processing direction of the next rolling.

[0016] Preferably, the homogenization treatment in step S2 is a process of bringing the heated alloy into contact with a cooling medium and cooling it from a certain temperature at a sufficiently fast rate so that part or all of the soluble components remain in the solid solution.

[0017] Preferably, the four rolling processes in step S4 are cold rolling, and the plate difference is reduced by cold rolling (equivalent to finish rolling), thereby ensuring that the finished plate has a smaller plate difference.

[0018] Preferably, the specific rolling method of the finished product in step S6 is cladding rolling.

[0019] Preferably, a width cutting device is required when cutting the plate in the step S2, and the width cutting device includes a support frame, a conveying frame is fixedly installed on the top of the support frame, and a plurality of conveying shafts are rotatably connected to the inner side of the conveying frame, and transverse moving components are fixedly installed on both sides of the conveying frame, and the moving ends of the two transverse moving components are fixedly installed with support frames, and a longitudinal moving component is fixedly installed on the bottom of the support frame, and a cutting device is fixedly installed on the moving end of the longitudinal moving component.

[0020] Preferably, a material discharge chute is provided inside the conveying frame, the material discharge chute is arranged at the bottom of the conveying shaft, a material feeding chute is provided at the top of the supporting frame, a sliding cavity is provided at the bottom of the material feeding chute, a ventilation cavity is provided at the bottom of the sliding cavity, an installation cavity is provided at the bottom of the ventilation cavity, an air outlet frame is fixedly installed at the bottom of the supporting frame, and the interior of the material discharge chute and the interior of the material feeding chute are connected.

[0021] Preferably, the inner side surface of the sliding cavity is slidably connected with a movable frame, one end of the movable frame is fixedly installed with a side panel, the side panel is arranged on one side of the support frame, the bottom of the movable frame is fixedly installed with a thread, the filter is arranged on the top of the ventilation cavity, an activated carbon placement cavity is opened inside the movable frame, limiting plates are fixedly installed on both sides of the inner side surface of the activated carbon placement cavity, a mounting frame is arranged on the top of the limiting plate, a filter frame is fixedly installed on the inner side surface of the mounting frame, and handles are fixedly installed on both sides of the inner side surface of the mounting frame.

[0022] Preferably, a mounting frame is fixedly mounted on the inner side surface of the mounting cavity, an exhaust fan is fixedly mounted inside the mounting frame, an input end of the exhaust fan is connected to the interior of the ventilation cavity, and an output end of the exhaust fan is connected to the interior of the air outlet frame.

[0023] Preferably, threaded sleeves are fixedly installed around the bottom of the support frame, the inner side surface of the threaded sleeve is threadedly connected with a threaded rod, and a pad is fixedly installed at the bottom of the threaded rod.

[0024] Compared with the related art, the preparation method of a TA15 titanium alloy thin plate provided by the present invention has the following beneficial effects:

[0025] The present invention provides a method for preparing a TA15 titanium alloy thin plate. The structure and properties of the TA15 thin plate are regulated by controlling rolling process parameters such as the rolling deformation after width cutting and the rolling heating temperature of the finished product. The reduction of the rolling deformation after width cutting and the increase of the rolling heating temperature of the finished product are beneficial to the reduction of the room temperature mechanical properties of the plate, thereby improving the stability of its mechanical properties. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1A flow chart of a method for preparing a TA15 titanium alloy thin plate provided by the present invention;

[0027] Figure 2 A schematic diagram of the structure of a width cutting device used in a method for preparing a TA15 titanium alloy thin plate provided by the present invention;

[0028] Figure 3 for Figure 2 The schematic diagram of the cross-sectional structure of the support frame shown;

[0029] Figure 4 for Figure 3 An enlarged schematic diagram of part A is shown;

[0030] Figure 5 The room temperature mechanical properties of the TA15 sheet of Example 1 under different heat treatment systems provided by the present invention;

[0031] Figure 6 The room temperature mechanical properties of the TA15 sheet of Example 2 under different heat treatment systems provided by the present invention;

[0032] Figure 7 The room temperature mechanical properties of the TA15 sheet of Example 3 under different heat treatment systems provided by the present invention;

[0033] Figure 8 The microstructure of the TA15 thin plate of Example 3 under different heat treatment systems provided by the present invention.

[0034] Numbers in the figure: 1. support frame, 11. feed chute, 12. sliding cavity, 13. ventilation cavity, 14. installation cavity, 15. air outlet frame, 2. threaded sleeve, 21. threaded rod, 22. pad, 3. moving frame, 31. side plate, 32. activated carbon placement cavity, 33. filter screen, 34. limit plate, 35. installation frame, 36. filter frame, 37. handle, 4. mounting frame, 41. exhaust fan, 5. conveying frame, 51. feed chute, 52. horizontal moving assembly, 53. support frame, 54. longitudinal moving assembly, 55. cutting equipment, 56. conveying shaft. DETAILED DESCRIPTION

[0035] The present invention will be further described below in conjunction with the accompanying drawings and implementation modes.

[0036] Please refer to Figure 1 , Figure 2 , Figure 3 , Figure 4 ,in, Figure 1 A flow chart of a method for preparing a TA15 titanium alloy thin plate provided by the present invention; Figure 2 A schematic diagram of the structure of a width cutting device used in a method for preparing a TA15 titanium alloy thin plate provided by the present invention; Figure 3 for Figure 2 The schematic diagram of the cross-sectional structure of the support frame shown; Figure 4 for Figure 3 A method for preparing a TA15 titanium alloy sheet comprises the following steps:

[0037] S1. Initially rolling a TA15 titanium alloy slab with a thickness of 150 mm at an initial rolling temperature of 10°C to 30°C above the β phase transformation point and a final rolling temperature of not less than 800°C to obtain a semi-finished plate with a thickness of 12 to 18 mm;

[0038] S2, cutting the semi-finished plate in step S1 into a uniform size;

[0039] S3, performing secondary rolling on the semi-finished plate in step S2 at an initial rolling temperature of 50°C to 90°C below the β phase transformation point and a final rolling temperature of not less than 800°C, and performing surface grinding treatment after air cooling to obtain a secondary semi-finished plate with a thickness of 6mm to 8mm;

[0040] S4, rolling the secondary semi-finished plate in step S3 for three times at an initial rolling temperature of 50°C to 90°C below the β phase transformation point and a final rolling temperature of not less than 800°C, and performing surface grinding after air cooling to obtain a tertiary semi-finished plate with a thickness of 4 mm;

[0041] S5, rolling the three-time semi-finished plate in step S4 for four times, and then performing surface grinding treatment to obtain a four-time semi-finished plate with a thickness of 3.5 mm;

[0042] S6, rolling the four semi-finished plates in step S5 at an initial rolling temperature of 880°C to 900°C and a final rolling temperature of not less than 800°C, and then performing surface grinding treatment to obtain a finished plate with a thickness of 1.0 mm;

[0043] S7, annealing the finished plate in step S6 by heat treatment system of keeping the temperature at 820°C to 880°C for 1 hour and then air cooling, and then performing surface treatment to obtain a finished plate that meets the technical requirements.

[0044] The width cutting in step S2 is to cut the plate to a certain length, rotate it 90 degrees for the next rolling, and the width of the plate is the processing direction of the next rolling.

[0045] The homogenization treatment in step S2 is a process of bringing the heated alloy into contact with a cooling medium and cooling it from a certain temperature at a sufficiently fast rate so that part or all of the soluble components remain in the solid solution.

[0046] The four rolling processes in step S4 are cold rolling, and the plate difference is reduced by cold rolling (equivalent to finish rolling), thereby ensuring that the finished plate has a smaller plate difference.

[0047] The specific rolling method of the finished product in step S6 is cladding rolling.

[0048] When the plate is cut to width in step S2, a width cutting device is required, and the width cutting device includes a support frame 1, a conveying frame 5 is fixedly installed on the top of the support frame 1, and a plurality of conveying shafts 56 are rotatably connected to the inner side of the conveying frame 5, and transverse moving components 52 are fixedly installed on both sides of the conveying frame 5, and support frames 53 are fixedly installed on the moving ends of the two transverse moving components 52, and a longitudinal moving component 54 is fixedly installed on the bottom of the support frame 53, and a cutting device 55 is fixedly installed on the moving end of the longitudinal moving component 54.

[0049] The cutting device 55 is a metal sheet cutting device commonly used in the prior art, such as flame cutting equipment, plasma cutting equipment and laser cutting equipment.

[0050] A material discharge chute 51 is provided inside the conveying frame 5, and the material discharge chute 51 is arranged at the bottom of the conveying shaft 56. A material feed chute 11 is provided on the top of the support frame 1, and a sliding cavity 12 is provided at the bottom of the material feed chute 11. A ventilation cavity 13 is provided at the bottom of the sliding cavity 12, and an installation cavity 14 is provided at the bottom of the ventilation cavity 13. An air outlet frame 15 is fixedly installed at the bottom of the support frame 1, and the interior of the material discharge chute 51 is connected with the interior of the material feed chute 11.

[0051] The feed chute 51 is conical, with a larger opening at the top and a smaller opening at the bottom, so that the generated debris and gas can be guided to the inner side of the feed chute 11 .

[0052] The inner side surface of the sliding cavity 12 is slidably connected with a moving frame 3, one end of the moving frame 3 is fixedly installed with a side plate 31, the side plate 31 is arranged on one side of the support frame 1, the bottom of the moving frame 3 is fixedly installed with a thread 33, the filter screen 33 is arranged on the top of the ventilation cavity 13, an activated carbon placement cavity 32 is opened inside the moving frame 3, both sides of the inner side surface of the activated carbon placement cavity 32 are fixedly installed with limit plates 34, a mounting frame 35 is arranged on the top of the limit plate 34, a filter frame 36 is fixedly installed on the inner side surface of the mounting frame 35, and handles 37 are fixedly installed on both sides of the inner side surface of the mounting frame 35.

[0053] A mounting frame 4 is fixedly mounted on the inner side of the mounting cavity 14 , and an exhaust fan 41 is fixedly mounted inside the mounting frame 4 . The input end of the exhaust fan 41 is connected to the interior of the ventilation cavity 13 , and the output end of the exhaust fan 41 is connected to the interior of the air outlet frame 15 .

[0054] Threaded sleeves 2 are fixedly installed around the bottom of the support frame 1 , a threaded rod 21 is threadedly connected to the inner side of the threaded sleeve 2 , and a pad 22 is fixedly installed at the bottom of the threaded rod 21 .

[0055] When in use, the sheet is moved to the bottom of the cutting device 55 by the rotation of the conveying shaft 56, and then the cutting device 55 is driven to move on the top of the sheet by the movement of the lateral moving assembly 52 and the longitudinal moving assembly 54, so as to cut the sheet. At the same time, the exhaust fan 41 is started to convey the gas from the feed chute 51 through the feed chute 11, the activated carbon placement chamber 32 and the ventilation chamber 13 to the inside of the gas outlet frame 15, and then discharged;

[0056] When the air is exhausted, the debris and gas generated by the cutting will enter the inner side of the installation frame 35 through the feed chute 51 and the feed chute 11, and be filtered by the filter frame 36, so that the debris docks on the top of the filter frame 36. When cleaning later, the user only needs to pull the movable frame 3 out of the inner side of the sliding cavity 12, and then hold the two handles 37 to drive the installation frame 35 to take out the filter frame 36 from the inner side of the activated carbon placement cavity 32, so as to clean the filter frame 36.

[0057] When in use, activated carbon can be placed on the inner side of the activated carbon placement cavity 32 to adsorb the toxic gas generated during cutting, and then discharge it through the gas outlet frame 15;

[0058] When the ground is uneven, the user can rotate the pad 22 so that the pad 22 drives the threaded rod 21 to be threadedly connected inside the threaded sleeve 2, so that the bottom of the threaded rod 21 drives the pad 22 to move downward, so that the level of the support frame 1 can be adjusted to avoid tilting.

[0059] Compared with the related art, the preparation method of a TA15 titanium alloy thin plate provided by the present invention has the following beneficial effects:

[0060] The microstructure and properties of TA15 thin plate are regulated by controlling the rolling process parameters such as the rolling deformation after cutting and the heating temperature of the finished product. The reduction of the rolling deformation after cutting and the increase of the heating temperature of the finished product are beneficial to the reduction of the room temperature mechanical properties of the plate and the improvement of the stability of its mechanical properties.

[0061] Embodiment 1

[0062] The specific process of this embodiment is:

[0063] Step 1: initially rolling a TA15 titanium alloy slab with a thickness of 150 mm at an initial rolling temperature of 10°C to 30°C above the β phase transformation point and a final rolling temperature of not less than 800°C to obtain a semi-finished plate with a thickness of 18 mm;

[0064] Step 2: Cut the semi-finished plate in step 1 into width and perform homogenization treatment;

[0065] Step 3: performing secondary rolling on the semi-finished plate in step 2 at an initial rolling temperature of 50°C to 90°C below the β phase transformation point and a final rolling temperature of not less than 800°C, and performing surface grinding after air cooling to obtain a secondary semi-finished plate with a thickness of 8 mm;

[0066] Step 4: rolling the secondary semi-finished plate in step 3 for three times at an initial rolling temperature of 50°C to 90°C below the β phase transformation point and a final rolling temperature of not less than 800°C, and performing surface grinding after air cooling to obtain a tertiary semi-finished plate with a thickness of 4 mm;

[0067] Step 5: cold rolling (four-time rolling) the three-time semi-finished plate in step 4, and then performing surface grinding treatment to obtain a four-time semi-finished plate with a thickness of 3.5 mm;

[0068] Step 6: rolling the four semi-finished plates in step 5 at an initial rolling temperature of 900° C. and a final rolling temperature of not less than 800° C., and then performing surface grinding to obtain a finished plate with a thickness of 1.0 mm;

[0069] Step 7: annealing the finished plate in step 6 by heat treatment at 750°C to 880°C for 1 hour and then air cooling, and then performing surface treatment to obtain a finished plate that meets the technical requirements;

[0070] Treatment result evaluation: The preferred heat treatment system for δ1.0mm TA15 thin plate is 820~880℃ / 60′. After the full process of the invention, the room temperature mechanical properties of the plate meet the following requirements: 930≤Rm≤1130MPa, Rρ0.2≥855MPa, A≥12% of the finished plate. On the basis of high temperature endurance performance meeting the condition of 500℃, 470MPa for 50h without breaking, the horizontal and vertical specimens can be kept for 50h without breaking, and the endurance performance is good, and a good treatment effect is achieved, see attached Figure 5 and the table below.

[0071]

[0072] Embodiment 2

[0073] The specific process of this embodiment is:

[0074] Step 1: initially rolling a TA15 titanium alloy slab with a thickness of 150 mm at an initial rolling temperature of 10°C to 30°C above the β phase transformation point and a final rolling temperature of not less than 800°C to obtain a semi-finished plate with a thickness of 12 mm;

[0075] Step 2: Cut the semi-finished plate in step 1 into width and perform homogenization treatment;

[0076] Step 3: The semi-finished plate in step 2 is subjected to secondary rolling at an initial rolling temperature of 50°C to 90°C below the β phase transformation point and a final rolling temperature of not less than 800°C, and then subjected to surface grinding after air cooling to obtain a secondary semi-finished plate with a thickness of 6.5 mm;

[0077] Step 4: rolling the secondary semi-finished plate in step 3 for three times at an initial rolling temperature of 50°C to 90°C below the β phase transformation point and a final rolling temperature of not less than 800°C, and performing surface grinding after air cooling to obtain a tertiary semi-finished plate with a thickness of 4 mm;

[0078] Step 5: cold rolling (four-time rolling) the three-time semi-finished plate in step 4, and then performing surface grinding treatment to obtain a four-time semi-finished plate with a thickness of 3.5 mm;

[0079] Step 6: The four semi-finished plates in step 5 are rolled five times at an initial rolling temperature of 880° C. and a final rolling temperature of not less than 800° C. to obtain finished plates, and then surface grinding treatment is performed to obtain finished plates with a thickness of 1.0 mm;

[0080] Step 7: annealing the finished plate in step 6 by heat treatment at 750°C to 880°C for 1 hour and then air cooling, and then performing surface treatment to obtain a finished plate that meets the technical requirements;

[0081] Treatment result evaluation: The preferred heat treatment system for δ1.0mm TA15 thin plate is 820~880℃ / 60′. After the full process of the invention, the room temperature mechanical properties of the plate meet the following requirements: 930≤Rm≤1130MPa, Rρ0.2≥855MPa, A≥12% of the finished plate. On the basis of high temperature endurance performance meeting the condition of 500℃, 470MPa for 50h without breaking, the horizontal and vertical specimens can be kept for 50h without breaking, and the endurance performance is good, and a good treatment effect is achieved, see attached Figure 6 and the table below.

[0082]

[0083] Embodiment 3

[0084] The specific process of this embodiment is:

[0085] Step 1: initially rolling a TA15 titanium alloy slab with a thickness of 150 mm at an initial rolling temperature of 10°C to 30°C above the β phase transformation point and a final rolling temperature of not less than 800°C to obtain a semi-finished plate with a thickness of 12 mm;

[0086] Step 2: Cut the semi-finished plate in step 1 into width and perform homogenization treatment;

[0087] Step 3: The semi-finished plate in step 2 is subjected to secondary rolling at an initial rolling temperature of 50°C to 90°C below the β phase transformation point and a final rolling temperature of not less than 800°C, and then subjected to surface grinding after air cooling to obtain a secondary semi-finished plate with a thickness of 6.5 mm;

[0088] Step 4: rolling the secondary semi-finished plate in step 3 for three times at an initial rolling temperature of 50°C to 90°C below the β phase transformation point and a final rolling temperature of not less than 800°C, and performing surface grinding after air cooling to obtain a tertiary semi-finished plate with a thickness of 4 mm;

[0089] Step 5: cold rolling (four-time rolling) the three-time semi-finished plate in step 4, and then performing surface grinding treatment to obtain a four-time semi-finished plate with a thickness of 3.5 mm;

[0090] Step 6: The four semi-finished plates in step 5 are rolled five times at an initial rolling temperature of 900° C. and a final rolling temperature of not less than 800° C. to obtain finished plates, and then surface grinding is performed to obtain finished plates with a thickness of 1.0 mm;

[0091] Step 7: annealing the finished plate in step 6 by heat treatment at 750°C to 880°C for 1 hour and then air cooling, and then performing surface treatment to obtain a finished plate that meets the technical requirements;

[0092] Treatment result evaluation: The preferred heat treatment system for δ1.0mm TA15 thin plate is 820~880℃ / 60′. After the full process of the invention, the room temperature mechanical properties of the plate meet the following requirements: 930≤Rm≤1130MPa, Rρ0.2≥855MPa, A≥12% of the finished plate. On the basis of high temperature endurance performance meeting the condition of 500℃, 470MPa for 50h without breaking, the horizontal and vertical specimens can be kept for 50h without breaking, and the endurance performance is good, and a good treatment effect is achieved, see attached Figure 7 and the table below.

[0093]

[0094] The microstructure and properties of TA15 thin plate are regulated by controlling the heat treatment system. Under different rolling processes, as the heat treatment temperature increases, the activation energy increases, the grain size of the plate gradually grows, and the grain boundary gradually becomes clear (see attached). Figure 8 ; Both the room temperature tensile properties and the high temperature tensile properties gradually decrease and then tend to be stable; the high temperature endurance performance is more stable;

[0095] By controlling the heat treatment system and rolling process parameters, the present invention can know that the rolling deformation after cutting is 90%-94%, the finished product rolling heating temperature is 880-900°C, and the heat treatment system is 820-880°C for insulation for 1h and then air-cooled. The performance of the TA15 thin plate can meet the following requirements: high temperature endurance performance is not broken for 50h under the conditions of 500°C and 470MPa; the room temperature mechanical properties meet the following requirements: 930≤Rm≤1130MPa, Rρ0.2≥855MPa, A≥12%.

[0096] The above descriptions are merely embodiments of the present invention and are not intended to limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made using the contents of the present invention specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A method for preparing a TA15 titanium alloy sheet, characterized in that: The following steps are involved: S1. Initially rolling a TA15 titanium alloy slab with a thickness of 150 mm at an initial rolling temperature of 10°C to 30°C above the β phase transformation point and a final rolling temperature of not less than 800°C to obtain a semi-finished plate with a thickness of 12 to 18 mm; S2, cutting the semi-finished plate in step S1 into a uniform size; S3, performing secondary rolling on the semi-finished plate in step S2 at an initial rolling temperature of 50°C to 90°C below the β phase transformation point and a final rolling temperature of not less than 800°C, and performing surface grinding treatment after air cooling to obtain a secondary semi-finished plate with a thickness of 6mm to 8mm; S4, rolling the secondary semi-finished plate in step S3 for three times at an initial rolling temperature of 50°C to 90°C below the β phase transformation point and a final rolling temperature of not less than 800°C, and performing surface grinding after air cooling to obtain a tertiary semi-finished plate with a thickness of 4 mm; S5, rolling the three-time semi-finished plate in step S4 for four times, and then performing surface grinding treatment to obtain a four-time semi-finished plate with a thickness of 3.5 mm; S6, rolling the four semi-finished plates in step S5 at an initial rolling temperature of 880°C to 900°C and a final rolling temperature of not less than 800°C, and then performing surface grinding treatment to obtain a finished plate with a thickness of 1.0 mm; S7, annealing the finished plate in step S6 by heat treatment system of keeping the temperature at 820°C to 880°C for 1 hour and then air cooling, and then performing surface treatment to obtain a finished plate that meets the technical requirements.

2. The method for preparing a TA15 titanium alloy sheet according to claim 1, characterized in that: The width cutting in step S2 is to cut the plate to a certain length, rotate it 90 degrees for the next rolling, and the width of the plate is the processing direction of the next rolling.

3. The method for preparing a TA15 titanium alloy sheet according to claim 1, characterized in that: The homogenization treatment in step S2 is a process of bringing the heated alloy into contact with a cooling medium and cooling it from a certain temperature at a sufficiently fast rate so that part or all of the soluble components remain in the solid solution.

4. The method for preparing a TA15 titanium alloy sheet according to claim 1, characterized in that: The four rolling processes in step S4 are cold rolling, and the plate difference is reduced by cold rolling (equivalent to finish rolling), thereby ensuring that the finished plate has a smaller plate difference.

5. The method for preparing a TA15 titanium alloy sheet according to claim 1, characterized in that: The specific rolling method of the finished product in step S6 is cladding rolling.

6. The method for preparing a TA15 titanium alloy sheet according to claim 1, characterized in that: When the plate is cut to width in step S2, a width cutting device is required, and the width cutting device includes a support frame, a conveying frame is fixedly installed on the top of the support frame, and a plurality of conveying shafts are rotatably connected to the inner side of the conveying frame, and transverse moving components are fixedly installed on both sides of the conveying frame, and the moving ends of the two transverse moving components are fixedly installed with support frames, and a longitudinal moving component is fixedly installed on the bottom of the support frame, and a cutting device is fixedly installed on the moving end of the longitudinal moving component.

7. The method for preparing a TA15 titanium alloy sheet according to claim 6, characterized in that: A material discharge chute is provided inside the conveying frame, and the material discharge chute is arranged at the bottom of the conveying shaft. A material feeding chute is provided at the top of the supporting frame, a sliding cavity is provided at the bottom of the material feeding chute, a ventilation cavity is provided at the bottom of the sliding cavity, and an installation cavity is provided at the bottom of the ventilation cavity. An air outlet frame is fixedly installed at the bottom of the supporting frame, and the interior of the material discharge chute and the interior of the material feeding chute are connected.

8. The method for preparing a TA15 titanium alloy sheet according to claim 7, characterized in that: The inner side surface of the sliding cavity is slidably connected with a moving frame, one end of the moving frame is fixedly installed with a side plate, the side plate is arranged on one side of the supporting frame, the bottom of the moving frame is fixedly installed with a thread, the filter is arranged on the top of the ventilation cavity, an activated carbon placement cavity is opened inside the moving frame, limiting plates are fixedly installed on both sides of the inner side surface of the activated carbon placement cavity, a mounting frame is arranged on the top of the limiting plate, a filter frame is fixedly installed on the inner side surface of the mounting frame, and handles are fixedly installed on both sides of the inner side surface of the mounting frame.

9. The method for preparing a TA15 titanium alloy sheet according to claim 8, characterized in that: A mounting frame is fixedly mounted on the inner side of the mounting cavity, an exhaust fan is fixedly mounted inside the mounting frame, an input end of the exhaust fan is connected to the interior of the ventilation cavity, and an output end of the exhaust fan is connected to the interior of the air outlet frame.

10. The method for preparing a TA15 titanium alloy sheet according to claim 9, characterized in that: Threaded sleeves are fixedly installed around the bottom of the support frame, the inner side surface of the threaded sleeve is threadedly connected with a threaded rod, and a pad is fixedly installed at the bottom of the threaded rod.

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