Preparation method of thin-gauge high-performance TC4 alloy single sheet
By performing β-phase zone quenching and multi-stage cold rolling treatment during the preparation of titanium alloy sheets, the problems of rolling texture and anisotropy in the preparation of TC4 alloy single sheets are solved, and thin-specification sheets with high performance and small performance differences are achieved.
Patent Information
- Application Number
- CN202411741394.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-11-29
- Publication Date
- 2025-03-04
AI Technical Summary
There is difficulty in preparing titanium alloy sheets in terms of thin specifications and high performance, especially in the preparation of TC4 alloy single sheets, rolled texture is easy to form, resulting in anisotropy of the sheet performance, and the processing of thin specification sheets is more difficult.
After the blank rolling, β-phase zone quenching is carried out, and fine needle-like or sheet-like martensite structure is formed through quenching to promote grain refinement in the subsequent cold rolling process. At the same time, two cold rolling processes are used, and the deformation amount is adjusted during the rolling process to ensure accurate control of the plate thickness.
The TC4 alloy single sheet prepared by this method has high strength performance, small differences in cross-sectional and longitudinal mechanical properties, which improves the anisotropy of the sheet and improves the application performance of thin-spec sheets.
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Figure CN119553202A_ABST
Abstract
Description
Technical Field
[0001] The invention relates to the technical field of titanium alloy plate preparation, and in particular to a method for preparing a thin-gauge high-performance TC4 alloy single plate. Background Art
[0002] Titanium alloy materials have many excellent performance characteristics, such as high specific strength, good corrosion resistance, high toughness and certain oxidation resistance, so they are widely used in important fields such as aerospace, chemical equipment and medical equipment. TC4 alloy has comprehensive properties such as high strength, high toughness, good corrosion resistance and good biocompatibility. It is the most widely used grade in structural titanium alloys, accounting for more than 50% of the total titanium consumption. Many other grades of alloys are developed based on TC4. Among the processed materials of TC4 titanium alloy, TC4 alloy plate and strip are the most used.
[0003] Titanium is a close-packed hexagonal metal with few slip systems and poor plasticity. It is easy to form rolling texture during rolling deformation, resulting in anisotropy of plate performance. TC4 alloy plates are stronger than industrial pure titanium plates, and are more difficult to process in terms of plate size difference, plate shape control and surface quality, especially the preparation of thin TC4 single plates. At the same time, with the promotion of titanium materials in the fields of aerospace, marine ships, the demand for titanium plate products, output and performance continues to increase. Summary of the invention
[0004] The purpose of the present invention is to provide a method for preparing a thin high-performance TC4 alloy single plate (1.5-2.0 mm). The plate prepared by the method has good comprehensive performance and small difference in transverse and longitudinal mechanical properties, so that the titanium alloy plate can be better used.
[0005] In order to achieve the above object, the technical solution of the present invention is as follows:
[0006] The present invention provides a method for preparing a thin-gauge high-performance TC4 alloy single plate, comprising the following steps:
[0007] Step 1: Billet rolling
[0008] The titanium alloy plate with a thickness of 45 to 70 mm is heated and then subjected to slab rolling to obtain a first slab with a thickness of 9 to 12 mm;
[0009] Step 2: Slab quenching
[0010] The first slab is heated and immediately subjected to β-phase quenching treatment after being taken out of the furnace to obtain a quenched slab;
[0011] Step 3: Surface treatment of quenched slab
[0012] The quenched slab is peeled and ground as a whole, and the surface oxide scale and crack defects are removed through grinding treatment, and the thickness of a single side is reduced by 0.2 to 0.3 mm;
[0013] Step 4: Second fire rolling
[0014] The quenched slab obtained in step 3 is heated and then subjected to a second hot rolling to obtain a second slab with a thickness of 4.4 to 6.0 mm;
[0015] Step 5: Third Fire Rolling
[0016] The second slab is heated and then subjected to a third hot rolling to obtain a third slab with a thickness of 2.5 to 3.0 mm;
[0017] Step 6: Third slab annealing
[0018] The third slab is kept in a heating furnace at a temperature of 800 to 840° C. for 20 to 30 minutes, and air-cooled after being taken out of the furnace to obtain an annealed slab;
[0019] Step 7: First cold rolling process
[0020] The annealed slab is sent to a cold rolling mill for cold rolling. The total number of cold rolling passes is 11 to 15. The deformation of the first two cold rolling passes is controlled at 2 to 5%. Then the deformation of each pass is gradually increased. The cumulative rolling deformation is 20 to 25%, and a first rolling pass plate with a thickness of 1.9 to 2.5 mm is obtained.
[0021] Step 8: First rolling plate annealing
[0022] The first rolling process plate is kept in a heating furnace at a temperature of 800-840°C for 10-20 minutes, air-cooled after being taken out of the furnace, and then alkali pickled to remove the surface oxide layer, and ground, and the surface is partially ground until there is no visible crack;
[0023] Step 9: Second cold rolling process
[0024] The annealed first rolling pass plate is cold rolled, the total number of cold rolling passes is 9 to 13, the deformation of the last two cold rolling passes is controlled at 2 to 5%, and the cumulative rolling deformation is 20 to 25%, to obtain a second rolling pass plate with a thickness of 1.5 to 2.0 mm;
[0025] Step 10: Second rolling plate annealing and post-treatment
[0026] The second rolling process plate is kept in a heating furnace at a temperature of 760-800°C for 15-25 minutes, air-cooled after being taken out of the furnace, and then press-corrected, alkaline pickled, surface ground, and cut by a shearing machine to obtain a finished plate.
[0027] In the above technical solution, further, in step 1, the heating temperature is 950-980° C., and the insulation time is 60-70 minutes.
[0028] In the above technical solution, further, in step 1, the rolling deformation amount of the slab rolling is 80-90%.
[0029] In the above technical solution, further, in step 2, the heating temperature is 1030-1050° C., and the insulation time is 15-20 min;
[0030] The medium for the quenching treatment is water.
[0031] In the above technical solution, further, in step 4, the heating temperature is 920-950° C., and the insulation time is 12-18 minutes.
[0032] In the above technical solution, further, in step 4, the second hot rolling adopts reversing rolling, the rolling direction is perpendicular to the rolling direction of the slab rolling, and the rolling deformation is 50-60%.
[0033] In the above technical solution, further, in step five, the heating temperature is 930-950° C., and the insulation time is 6-8 minutes.
[0034] In the above technical solution, further, in step five, the rolling deformation amount of the third hot rolling is 40-50%.
[0035] The beneficial effects of the present invention are:
[0036] The preparation method of the present invention performs β-phase quenching after hot rolling. Fine needle-shaped or lamellar martensite structure can be obtained through quenching treatment. The martensite can promote grain refinement in the subsequent cold rolling process, thereby ensuring that a single plate has high strength performance; two rolling processes are used in the cold rolling process, and the deformation amount at the beginning of the first rolling process and the deformation amount at the end of the second rolling process are regulated in the rolling process, thereby achieving accurate control of the thickness specification of thin-gauge plates and improving the size difference of the same plate of the finished plates.
[0037] The present invention effectively improves the anisotropy of the plate by quenching after blanking and reversing hot rolling. The single plate prepared by this method has small differences in transverse and longitudinal properties, which will be beneficial for the use of the alloy single plate in more application scenarios. BRIEF DESCRIPTION OF THE DRAWINGS
[0038] Figure 1 This is a microstructure diagram of a single sheet of TC4 alloy prepared in Example 1;
[0039] Figure 2 This is a microstructure diagram of a single sheet of TC4 alloy prepared in Example 2;
[0040] Figure 3 This is the microstructure diagram of a single TC4 alloy plate prepared in Example 3. DETAILED DESCRIPTION
[0041] The following examples may enable those skilled in the art to more fully understand the present invention, but are not intended to limit the present invention in any way.
[0042] Example 1
[0043] This embodiment provides a method for preparing a thin-gauge high-performance TC4 alloy single plate, comprising the following steps:
[0044] Step 1: Billet rolling
[0045] A titanium alloy plate with a thickness of 55 mm was kept in a heating furnace at a temperature of 960° C. for 60 minutes, and then subjected to slab rolling with a rolling deformation of 82% to obtain a hot-rolled slab with a thickness of 10 mm, which was referred to as the first slab;
[0046] Step 2: Slab quenching
[0047] The first slab is placed in a heating furnace at a temperature of 1040° C. for 15 minutes, and then immediately enters an online quenching section for β-phase quenching treatment with water as the quenching medium to obtain a quenched slab;
[0048] Step 3: Surface treatment of quenched slab
[0049] The quenched slab is peeled and ground as a whole to remove the surface oxide scale and crack defects, and the single-side thickness is reduced by 0.2mm to obtain a quenched slab with qualified surface quality, and then cut into pieces;
[0050] Step 4: Second fire rolling
[0051] The quenched slab after grinding was kept in a heating furnace at 940°C for 15 minutes, and then subjected to the second rolling process. The second rolling process adopts reversing rolling, and the rolling direction is perpendicular to the rolling direction of the blanking rolling. The rolling deformation is 50%, and a slab with a thickness of 4.8 mm is obtained, which is called the second slab.
[0052] Step 5: Third Fire Treatment
[0053] The second slab with a thickness of 4.8 mm was kept in a heating furnace at a temperature of 940° C. for 7 minutes, and then subjected to a third hot rolling process with a rolling deformation of 44% to obtain a slab with a thickness of 2.7 mm, which was referred to as the third slab;
[0054] Step 6: Third slab annealing
[0055] The third slab was kept in a heating furnace at a temperature of 820° C. for 25 minutes, and then air-cooled after being taken out of the furnace to obtain an annealed slab, and then alkaline pickling was performed to remove the surface oxide layer, and the surface was partially ground until no visible cracks were found, thereby obtaining a plate to be further cold-rolled;
[0056] Step 7: First cold rolling process
[0057] The annealed slab was sent to a cold rolling mill for cold rolling for 11 passes. The deformation of the first two cold rolling passes was controlled at 5%, and then the deformation of each pass was gradually increased. The cumulative rolling deformation was 22%, and a 2.1 mm thick plate was obtained, which was the first rolling pass plate.
[0058] Step 8: First rolling plate annealing
[0059] The first rolling process plate is kept in a heating furnace at a temperature of 820°C for 20 minutes, air-cooled after being taken out of the furnace, and then alkali pickling is performed to remove the surface oxide layer, and the surface is partially ground until no visible cracks are present, thereby obtaining a plate to be further cold-rolled;
[0060] Step 9: Second cold rolling process
[0061] The annealed first rolling pass plate is cold rolled for 9 passes, and the deformation of the last two cold rolling passes is controlled at 3%, and the cumulative rolling deformation is 24%, to obtain a plate with a thickness of 1.6 mm, which is called the second rolling pass plate;
[0062] Step 10: Second rolling plate annealing and post-treatment
[0063] The second rolling process plate is kept in a heating furnace at 780℃ for 20 minutes, air-cooled after being taken out of the furnace, and then press-corrected, alkaline pickled, surface-grinded, and cut by a shearing machine to obtain the final finished plate. The difference in size between the same plate is 0.05-0.13mm. Figure 1 The microstructure of a single plate and its mechanical properties are shown in Table 1.
[0064] Example 2
[0065] This embodiment provides a method for preparing a thin-gauge high-performance TC4 alloy single plate, comprising the following steps:
[0066] Step 1: Billet rolling
[0067] A titanium alloy plate with a thickness of 46 mm was kept in a heating furnace at a temperature of 960° C. for 55 minutes, and then subjected to slab rolling with a rolling deformation of 76% to obtain a hot-rolled slab with a thickness of 11 mm, which was referred to as the first slab;
[0068] Step 2: Slab quenching
[0069] The first slab is placed in a heating furnace at a temperature of 1040° C. for 16 minutes, and then immediately enters an online quenching section for β-phase quenching treatment after being taken out of the furnace. The quenching medium is water, and a quenched slab is obtained.
[0070] Step 3: Surface treatment of quenched slab
[0071] The quenched slab is peeled and ground as a whole to remove the surface oxide scale and crack defects, and the single-side thickness is reduced by 0.25mm to obtain a quenched slab with qualified surface quality, and then cut into pieces;
[0072] Step 4: Second fire rolling
[0073] The ground quenched slab was kept in a heating furnace at 940°C for 16 minutes, and then subjected to the second rolling process. The second rolling process adopted reversing rolling, and the rolling direction was perpendicular to the rolling direction of the blanking rolling. The rolling deformation was 57%, and a slab with a thickness of 4.5 mm was obtained, which was called the second slab.
[0074] Step 5: Third Fire Treatment
[0075] The second slab with a thickness of 4.5 mm was kept in a heating furnace at a temperature of 940° C. for 7 minutes, and then subjected to a third hot rolling process with a rolling deformation of 47% to obtain a slab with a thickness of 2.4 mm, which was referred to as the third slab;
[0076] Step 6: Third slab annealing
[0077] The third slab was kept in a heating furnace at a temperature of 820° C. for 25 minutes, and then air-cooled after being taken out of the furnace to obtain an annealed slab, and then alkaline pickling was performed to remove the surface oxide layer, and the surface was partially ground until no visible cracks were found, thereby obtaining a plate to be further cold-rolled;
[0078] Step 7: First cold rolling process
[0079] The annealed slab was sent to a cold rolling mill for cold rolling for 13 passes. The deformation of the first two cold rolling passes was controlled at 3%, and then the deformation of each pass was gradually increased. The cumulative rolling deformation was 21%, and a 1.9 mm thick plate was obtained, which was the first rolling pass plate.
[0080] Step 8: First rolling plate annealing
[0081] The first rolling process plate is kept in a heating furnace at a temperature of 820°C for 20 minutes, air-cooled after being taken out of the furnace, and then alkali pickling is performed to remove the surface oxide layer, and the surface is partially ground until no visible cracks are present, thereby obtaining a plate to be further cold-rolled;
[0082] Step 9: Second cold rolling process
[0083] The annealed first rolling pass plate is cold rolled for 11 passes, and the deformation of the last two cold rolling passes is controlled at 3%, and the cumulative rolling deformation is 21%, and a plate with a thickness of 1.5 mm is obtained, which is called the second rolling pass plate;
[0084] Step 10: Second rolling plate annealing and post-treatment
[0085] The second rolling process plate is kept in a heating furnace at 780℃ for 20 minutes, air-cooled after being taken out of the furnace, and then press-corrected, alkaline pickled, surface-grinded, and cut by a shearing machine to obtain the final finished plate. The difference in size between the same plate is 0.08-0.15mm. Figure 2 The microstructure of a single plate and its mechanical properties are shown in Table 1.
[0086] Example 3
[0087] This embodiment provides a method for preparing a thin-gauge high-performance TC4 alloy single plate, comprising the following steps:
[0088] Step 1: Billet rolling
[0089] A titanium alloy plate with a thickness of 65 mm was kept in a heating furnace at a temperature of 960° C. for 70 minutes, and then subjected to slab rolling with a rolling deformation of 82% to obtain a hot-rolled slab with a thickness of 12 mm, which was referred to as the first slab;
[0090] Step 2: Slab quenching
[0091] The first slab is placed in a heating furnace at a temperature of 1050° C. for 18 minutes, and then immediately enters an online quenching section for β-phase quenching treatment after being taken out of the furnace. The quenching medium is water, and a quenched slab is obtained.
[0092] Step 3: Surface treatment of quenched slab
[0093] The quenched slab is peeled and ground as a whole to remove the surface oxide scale and crack defects, and the single-side thickness is reduced by 0.30mm to obtain a quenched slab with qualified surface quality, and then cut into pieces;
[0094] Step 4: Second fire rolling
[0095] The ground quenched slab was kept in a heating furnace at 940°C for 17 minutes, and then subjected to the second rolling process. The second rolling process adopted reversing rolling, and the rolling direction was perpendicular to the rolling direction of the blanking rolling. The rolling deformation was 53%, and a slab with a thickness of 5.4 mm was obtained, which was called the second slab.
[0096] Step 5: Third Fire Treatment
[0097] The second slab with a thickness of 5.4 mm was kept in a heating furnace at a temperature of 940° C. for 8 minutes, and then subjected to a third hot rolling process with a rolling deformation of 46% to obtain a slab with a thickness of 2.9 mm, which was referred to as the third slab;
[0098] Step 6: Third slab annealing
[0099] The third slab was kept in a heating furnace at a temperature of 820° C. for 30 minutes, and then air-cooled after being taken out of the furnace to obtain an annealed slab, and then alkaline pickling was performed to remove the surface oxide layer, and the surface was partially ground until no visible cracks were found, thereby obtaining a plate to be further cold-rolled;
[0100] Step 7: First cold rolling process
[0101] The annealed slab is sent to a cold rolling mill for cold rolling for 12 passes. The deformation of the first two cold rolling passes is controlled at 3%, and then the deformation of each pass is gradually increased. The cumulative rolling deformation is 21%, and a 2.3 mm thick plate is obtained, which is the first rolling process plate.
[0102] Step 8: First rolling plate annealing
[0103] The first rolling process plate is kept in a heating furnace at a temperature of 820°C for 25 minutes, air-cooled after being taken out of the furnace, and then alkali pickling is performed to remove the surface oxide layer, and the surface is partially ground until no visible cracks are present, thereby obtaining a plate to be further cold-rolled;
[0104] Step 9: Second cold rolling process
[0105] The annealed first rolling pass plate is cold rolled for 11 passes, and the deformation of the last two cold rolling passes is controlled at 4%, and the cumulative rolling deformation is 22%, to obtain a plate with a thickness of 1.8 mm, which is called the second rolling pass plate;
[0106] Step 10: Second rolling plate annealing and post-treatment
[0107] The second rolling process plate is kept in a heating furnace at 780℃ for 20 minutes, air-cooled after being taken out of the furnace, and then press-corrected, alkaline pickled, surface-grinded, and cut by a shearing machine to obtain the final finished plate. The difference in size between the same plate is 0.06-0.13mm. Figure 3 The microstructure of a single plate and its mechanical properties are shown in Table 1.
[0108] Table 1 Mechanical properties of TC4 alloy single sheet in the embodiment
[0109]
[0110] The above embodiments are only preferred embodiments of the present invention and are not intended to limit the implementation methods. The protection scope of the present invention shall be subject to the scope defined in the claims. Other different forms of changes or modifications may be made based on the above description. Obvious changes or modifications derived therefrom are still within the protection scope of the present invention.
Claims
1. A method for preparing a thin-gauge high-performance TC4 alloy single plate, characterized in that: The steps include: Step 1: Billet rolling The titanium alloy plate with a thickness of 45 to 70 mm is heated and then subjected to slab rolling to obtain a first slab with a thickness of 9 to 12 mm; Step 2: Slab quenching The first slab is heated and immediately subjected to β-phase quenching treatment after being taken out of the furnace to obtain a quenched slab; Step 3: Surface treatment of quenched slab Peel and grind the quenched slab as a whole; Step 4: Second fire rolling The quenched slab obtained in step 3 is heated and then subjected to a second hot rolling to obtain a second slab with a thickness of 4.4 to 6.0 mm; Step 5: Third Fire Rolling The second slab is heated and then subjected to a third hot rolling to obtain a third slab with a thickness of 2.5 to 3.0 mm; Step 6: Third slab annealing The third slab is kept in a heating furnace at a temperature of 800 to 840° C. for 20 to 30 minutes, and air-cooled after being taken out of the furnace to obtain an annealed slab; Step 7: First cold rolling process The annealed slab is sent to a cold rolling mill for cold rolling. The total number of cold rolling passes is 11 to 15. The deformation of the first two cold rolling passes is controlled at 2 to 5%. Then the deformation of each pass is gradually increased. The cumulative rolling deformation is 20 to 25%, and a first rolling pass plate with a thickness of 1.9 to 2.5 mm is obtained. Step 8: First rolling plate annealing The first rolling process plate is kept in a heating furnace at a temperature of 800-840°C for 10-20 minutes, air-cooled after being taken out of the furnace, and then alkali pickled and ground; Step 9: Second cold rolling process The annealed first rolling pass plate is cold rolled, the total number of cold rolling passes is 9 to 13, the deformation of the last two cold rolling passes is controlled at 2 to 5%, and the cumulative rolling deformation is 20 to 25%, to obtain a second rolling pass plate with a thickness of 1.5 to 2.0 mm; Step 10: Second rolling plate annealing and post-treatment The second rolling process plate is kept in a heating furnace at a temperature of 760-800°C for 15-25 minutes, air-cooled after being taken out of the furnace, and then press-corrected, alkaline pickled, surface ground, and cut by a shearing machine to obtain a finished plate.
2. The preparation method according to claim 1, characterized in that: In step 1, the heating temperature is 950-980° C., and the insulation time is 60-70 minutes.
3. The preparation method according to claim 1, characterized in that: In step 1, the rolling deformation of the slab rolling is 80-90%.
4. The preparation method according to claim 1, characterized in that: In step 2, the heating temperature is 1030-1050° C. and the holding time is 15-20 min; The medium for the quenching treatment is water.
5. The preparation method according to claim 1, characterized in that: In step 4, the heating temperature is 920-950° C., and the insulation time is 12-18 minutes.
6. The preparation method according to claim 1, characterized in that: In step 4, the second hot rolling adopts reversing rolling, the rolling direction is perpendicular to the rolling direction of the slab rolling, and the rolling deformation is 50-60%.
7. The preparation method according to claim 1, characterized in that: In step 5, the heating temperature is 930-950° C., and the insulation time is 6-8 minutes.
8. The preparation method according to claim 1, characterized in that: In step 5, the rolling deformation amount of the third hot rolling is 40-50%.