Preparation method of TA1-TA10 winding tape

Abstract

The invention provides a preparation method of a TA1-TA10 winding tape. The preparation method specifically comprises the following steps: S1, smelting a cast ingot; s2, preparing a plate blank; s3, plate blank coating is conducted, specifically, the upper surface and the lower surface of the to-be-rolled plate blank are coated with pure TA2 thin plates correspondingly in an explosive cladding mode; s4, plate blank heating, wherein the coated plate blank is conveyed to a heating furnace to be heated and rolled, and the plate blank is subjected to heat preservation after passing through a preheating area, a first heating area and a second heating area of the heating furnace; when heating is conducted in a first heating area, the temperature ranges from room temperature to 550 DEG C, and the heating time is shorter than 180 min; when heating is conducted in the second heating area, the temperature ranges from 750 DEG C to 820 DEG C, and the heating time ranges from 120 min to 180 min; s5, rolling a black skin roll; s6, annealing the black skin roll in a bell-type furnace at the annealing temperature of 570-720 DEG C; the annealing temperature of the bell-type furnace adopts a gradient heating mode; and S7, shot blasting and acid pickling are conducted on the coiled tape, and then the TA1-TA10 coiled tape with the silver bright surface is obtained. According to the technical scheme, the problems of poor surface quality and poor structure uniformity of the titanium alloy coiled tape produced by an existing coiling method are solved.

Description

Technical Field

[0001] The present invention relates to the technical field of titanium alloys, and in particular to a method for preparing TA1-TA10 coils. Background Art

[0002] Titanium alloy has excellent properties such as low density, high specific strength and good corrosion resistance. As an important structural material, it has been widely used in aviation, aerospace, chemical industry, ships, automobiles, weapons, sports, medical and other fields. However, the large-scale application of titanium and its alloys is limited by its many surface defects, small single coil width, small coil weight, and high smelting and processing costs.

[0003] Titanium alloy coils produced by hot rolling of titanium steel can improve the utilization rate of rolling lines and increase corporate profits. During the heating process of the titanium alloy slab in the heating furnace, the flame is heated by a mixed atmosphere of blast furnace or converter gas and natural gas with low fuel value and low cost. However, the thermal conductivity of titanium is poor, which leads to a long heating time of the titanium billet in the steel enterprise heating furnace, severe surface oxidation, violent surface reaction, and severe cracking of the thick surface oxygen-rich brittle layer during the subsequent rolling process. The hot rolling temperature of titanium billets is generally greater than 870°C. During the medium and low temperature heating process of titanium, as the temperature rises, the film structure is composed of titanium oxides of different valence states. The oxide film increases in weight, but it is a dense layer with protective properties. When the temperature exceeds 800°C, the oxide film will gradually penetrate into the matrix, the oxide film will break, and it will no longer be dense. In the hot rolling process, in order to ensure the plasticity of the titanium billet, descaling water is basically not used, which will inevitably cause the surface hard oxide scale to be pressed into the matrix, causing surface defects and affecting the surface quality of the titanium coil.

[0004] When TA1 and TA2 titanium billets are heated to the rolling temperature of 870-910℃, the surface oxidation products are mainly TiO2 with different densities. In addition, the titanium slabs smelted in the EB furnace have relatively coarse grains, with a size of millimeters. At the same time, the density of the slabs that have not undergone VAR ingot forging is relatively small. Relatively speaking, their oxidation resistance is also different from that of the slabs that have undergone VAR forging. The stress generated by the different thermal expansion coefficients of the oxidation products generated on the surface and the matrix can easily lead to the shedding of the oxide film and the formation of microcracks in the subsequent rolling process, resulting in poor surface quality of the hot-rolled coils and severe edge cracks. Summary of the invention

[0005] In view of the above-mentioned technical problem that the surface quality of titanium alloy coils produced by the existing coiling method is poor, a TA1~TA10 coil preparation method is provided, which comprehensively controls the preparation process of TA1~TA10 titanium and titanium alloy coils from titanium billet preparation, heating, rolling and heat treatment, which can greatly improve the quality of titanium coils.

[0006] The technical means adopted by the present invention are as follows:

[0007] A method for preparing a TA1-TA10 tape comprises the following steps:

[0008] S1. Ingot smelting: The raw materials for preparing the titanium alloy are smelted into TA1-TA10 titanium alloy ingots by a vacuum electron beam cooling furnace (EB furnace), and then the ingots are melted into slabs;

[0009] S2. Slab preparation: grinding the six sides of the slab;

[0010] S3, slab coating: the upper and lower surfaces of the slab to be rolled are respectively coated with pure TA2 thin plates by explosive compounding;

[0011] S4, slab heating: the coated slab is sent to the heating furnace for heating and rolling. The slab passes through the preheating zone, the first heating zone, the second heating zone of the heating furnace and then goes to the 870℃~960℃ soaking zone for insulation for 120~180min. The total time in the furnace is less than 440min, and the time in the first heating zone and the second heating zone is less than 360min. After the insulation is completed, the slab is taken out of the furnace for rolling; wherein, when heating in the first heating zone, the temperature is from room temperature to 550℃, and the heating time is less than 180min; when heating in the second heating zone, the temperature is 750~820℃, and the heating time is 120~180min;

[0012] S5, black coil rolling: the slab is subjected to rough rolling, finish rolling and slow cooling by a 2050mm continuous rolling mill to obtain a black titanium coil, the final rolling temperature is greater than 720°C, and the coiling temperature is 550-600°C;

[0013] S6, black coil bell furnace annealing: after the rolling is completed, the coil is cooled and then subjected to recrystallization annealing in a bell furnace with electric heating and argon protection, with an annealing temperature of 570-720°C;

[0014] The annealing temperature of the bell-type furnace adopts a gradient heating method. The annealing process includes the following three stages:

[0015] (1) Heating from room temperature to 450°C, heating rate 60-100°C / h, holding time 300-480 min, circulating argon pressure 2.0-3.2 KPa, circulating argon flow rate 30 Nm 3 / h;

[0016] (2) Heating from 450°C to 570-720°C, heating rate 30-60°C / h, holding time 600-800 min, circulating argon pressure 3.2-5.0 KPa, circulating argon flow rate 50 Nm 3 / h;

[0017] (3) After the insulation is completed, the temperature is gradually lowered to 450°C at a rate of 10 to 30°C / h. After 180 to 240 minutes of insulation, the heating power is turned off, the heating cover is removed, and argon gas is continuously introduced for cooling. When the average temperature in the furnace is cooled to ≤140°C, the inner cover is removed and air cooling is performed;

[0018] S7. After shot blasting and pickling, the coil is subjected to silver-bright surface TA1-TA10 coil.

[0019] Furthermore, S1 specifically includes: melting the raw materials into TA1~TA10 titanium alloy ingots through a vacuum electron beam cooling hearth furnace according to the titanium alloy element range determined by TA1~TA10 titanium and titanium alloy grades and chemical composition standards, and then melting the ingots into slabs with a thickness of 240~330mm and a width of 1600~2200mm.

[0020] Furthermore, S2 specifically includes: grinding the slab, with the six-sided milling thickness being 10 to 20 mm; grinding the four long sides along the length direction of the slab to chamfers of 40 to 60 mm, and grinding the four wide sides along the width direction of the slab to chamfers of 50 to 80 mm.

[0021] Furthermore, S3 specifically includes: grinding the surface of the slab to be rolled to a bare metal color, and the surface roughness Ra satisfies 0.8μm<Ra<1.6μm, and then coating the upper and lower surfaces of the slab to be rolled with TA2 thin plates with a thickness of 0.8-2.0mm respectively by explosive composite method, the average Vickers hardness of the TA2 thin plates HV5<120, and the use area of ​​the TA2 thin plates is <30m 2 .

[0022] Furthermore, during the annealing process, the bell-type furnace maintains positive pressure circulating argon protection to prevent oxygen from entering the furnace. The argon pressure is 2.0-5.0 KPa, and the circulating argon flow rate is 30-80 Nm 3 / h; the coil is annealed in three layers, with the spacing between two adjacent layers of coil being 50 to 100 mm.

[0023] Further, S5 is subjected to rough rolling, finish rolling and slow cooling to obtain a hot rolled coil with a thickness of 3 to 12 mm and a width of 2000 to 2400 mm, which specifically includes:

[0024] Rough rolling: The slab is rolled to a thickness of 40-60 mm through a rough rolling mill;

[0025] Finishing rolling: After rough rolling, the finishing mill rolls the steel to a thickness of 3-12 mm; the finishing rolling inlet temperature is less than 820°C, and the strip threading speed is 1.5-3 m / s;

[0026] Slow cooling: After finishing rolling, the steel is coiled at a temperature of 550-600°C. After coiling, the steel is moved into the slow cooling zone for pile cooling at a temperature of 550°C. The steel is kept warm for 12-16 hours. After the heat preservation is completed, the steel is taken out of the furnace for air cooling.

[0027] Furthermore, in the S6 heating stage (1), for the 3-12 mm thick hot-rolled black coils of TA1-TA5, the heating rate is 100°C / h; for the 3-12 mm thick hot-rolled black coils of TA6-TA10, the heating rate is 60°C / h;

[0028] In the S6(2) heating stage, for the 3-12 mm thick hot-rolled black coils of TA1-TA5, the heating rate is 60°C / h; for the 3-12 mm thick hot-rolled black coils of TA6-TA10, the heating rate is 30°C / h.

[0029] Furthermore, in the S6(2) heating stage, the insulation temperature of TA1 and TA2 is 570-610°C, the insulation temperature of TA3 and TA4 is 610-640°C, the insulation temperature of TA5, TA6 and TA7 is 640-670°C, and the insulation temperature of TA7, TA8, TA9 and TA10 is 670-720°C.

[0030] Compared with the prior art, the present invention has the following advantages:

[0031] The TA1-TA10 coil preparation method provided by the present invention adopts the proposed titanium billet rolling method and rolling deformation, and can finally prepare wide hot-rolled titanium coils with a width of 1800-2400 mm, a thickness of 3-12 mm, and good surface quality, which solves the problem of poor surface quality of titanium alloy coils produced by the existing coil method, greatly improves product quality, reduces costs, increases the yield rate, and has good economic benefits.

[0032] Based on the above reasons, the present invention can be widely promoted in the field of titanium alloys. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0034] Figure 1 This is the metallographic image of the TA1 tape head prepared in Example 1 of the present invention.

[0035] Figure 2 This is the metallographic image of the tail of the TA1 tape prepared in Example 1 of the present invention.

[0036] Figure 3 This is the metallographic image of the TA1 tape prepared using the existing roll-to-roll method.

[0037] Figure 4 This is a scanning electron microscope image of the cross section of the TA1 tape prepared in Example 1 of the present invention.

[0038] Figure 5 This is a scanning electron microscope image of the cross section of the TA1 tape prepared using the existing roll-to-roll method.

[0039] Figure 6 This is the metallographic image of the TA10 tape head prepared in Example 2 of the present invention.

[0040] Figure 7 This is the metallographic image of the tail of the TA10 tape prepared in Example 2 of the present invention.

[0041] Figure 8 This is the metallographic image of the TA10 tape prepared using the existing roll-to-roll method.

[0042] Fig. 9 This is a scanning electron microscope image of the cross section of the TA10 tape prepared in Example 2 of the present invention.

[0043] Fig.10 This is a scanning electron microscope image of the cross section of the TA10 tape prepared using the existing roll-to-roll method. DETAILED DESCRIPTION

[0044] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. The following description of at least one exemplary embodiment is actually only illustrative and is by no means intended to limit the present invention and its application or use. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0045] The present invention provides a method for preparing TA1-TA10 coils, the process flow of which is: ingot smelting - slab preparation - slab coating - slab heating - black coil rolling - black coil hood furnace annealing - shot blasting - pickling; specifically comprising the following steps:

[0046] S1. Ingot smelting: The raw materials for preparing the titanium alloy are smelted into TA1-TA10 titanium alloy ingots by a vacuum electron beam cooling furnace (EB furnace), and then the ingots are melted into slabs;

[0047] S2. Slab preparation: grinding the six sides of the slab;

[0048] S3, slab coating: pure TA2 thin plates are coated on the upper and lower surfaces of the slab to be rolled respectively by explosive compounding; the present invention avoids direct contact between the titanium slab and the oxidizing atmosphere during heating through low-cost coating treatment, thereby improving the surface quality after deformation; the coating treatment can also avoid direct contact with the roller during the first few rolling passes, play a role in heat preservation and improve plastic deformation;

[0049] S4, slab heating: the coated slab is sent to the heating furnace for heating and rolling. After the slab passes through the preheating zone, the first heating zone and the second heating zone of the heating furnace, it is kept warm in the 870℃~960℃ equalizing zone for 120~180min. The total time in the furnace is less than 440min, and the time in the first heating zone and the second heating zone is less than 360min. After the insulation is completed, it is taken out of the furnace for rolling. The coated TA2 thin plate has low strength and good thermoplasticity at high temperature. After rolling, the obtained hot-rolled coil is shot blasted and pickled and then removed to obtain a titanium alloy coil with good surface quality. Among them, when heating in the first heating zone, the temperature is from room temperature to 550℃, and the heating time is less than 180min; when heating in the second heating zone, the temperature is 750~820℃, and the heating time is 120~180min. The segmented heating can avoid the uneven structure caused by overheating of the surface structure, and the total re-furnace time can be controlled to avoid the coarse grain phenomenon caused by long-term heating.

[0050] S5, black coil rolling: the slab is subjected to rough rolling, finish rolling and slow cooling to obtain black titanium coil, the final rolling temperature is greater than 720℃, and the coiling temperature is 550~600℃;

[0051] S5 is a hot-rolled coil with a thickness of 3 to 12 mm and a width of 2000 to 2400 mm obtained through rough rolling, finish rolling and slow cooling, which specifically includes:

[0052] Rough rolling: The slab is rolled to a thickness of 40-60 mm through a rough rolling mill;

[0053] Finishing rolling: After rough rolling, the finishing mill rolls the steel to a thickness of 3-12 mm. The finishing rolling inlet temperature is less than 820°C, and the strip threading speed is 1.5-3 m / s. TA1-TA10 has good high-temperature plasticity, and slow strip threading can avoid tail swinging and ensure the straightness of the strip. The finishing rolling inlet temperature is controlled to be less than 820°C. When the finishing rolling zone is rolled at a high speed, it can avoid the adiabatic heating caused by strain rate sensitivity to induce β phase transformation. After the phase transformation occurs, the Widmanstatten structure is easily formed in the subsequent cooling process, and the Widmanstatten structure will deteriorate the mechanical properties of the titanium alloy strip.

[0054] Slow cooling: After finishing rolling, the steel is coiled at a temperature of 550-600°C. After coiling, the steel is moved to a slow cooling zone for stack cooling at a temperature of 550°C for 12-16 hours. After the insulation period, the steel is taken out of the furnace for air cooling. Slow cooling in a slow cooling pit is beneficial to reducing residual stress and is beneficial to subsequent uncoiling.

[0055] S6, black coil bell furnace annealing: after the rolling is completed, the coil is cooled and then subjected to recrystallization annealing in a bell furnace with electric heating and argon protection, with an annealing temperature of 570-720°C;

[0056] The annealing temperature of the bell-type furnace adopts a gradient heating method. The radial thermal conductivity of the titanium coil is much lower than that of the circumferential and axial directions. The radial thermal conductivity is affected by the surface quality, thickness, and winding tension of the titanium coil. The gradient heating method is used to make the titanium coil heated evenly. The thermal conductivity of titanium is λ = 15.24W / (mK), which is about 1 / 4 of nickel, 1 / 5 of iron, and 1 / 14 of aluminum. The thermal conductivity of various titanium alloys is about 50% lower than that of titanium. Therefore, the heating rate needs to be strictly controlled to ensure uniform heat transfer. The annealing process includes the following three stages:

[0057] (1) Heating from room temperature to 450°C, heating rate 60-100°C / h, holding time 300-480 min, circulating argon pressure 2.0-3.2 KPa, circulating argon flow rate 30 Nm 3 / h;

[0058] (2) The temperature is increased from 450°C to 570-720°C, the heating rate is 30-60°C / h, the holding time is 600-800min, the circulating argon pressure is 3.2-5.0KPa, and the circulating argon flow rate is 50Nm3 / h; the recrystallization temperature of the hot-rolled TA1-TA10 coils is about 540-750°C. Long-term holding within this temperature range can make the internal structure equiaxed and ensure good mechanical properties;

[0059] (3) After the insulation is completed, the temperature is gradually lowered to 450°C at a rate of 10 to 30°C / h. After 180 to 240 minutes of insulation, the heating power is turned off, the heating cover is removed, and argon gas is continuously introduced for cooling. When the average temperature in the furnace is cooled to ≤140°C, the inner cover is removed and air cooling is performed;

[0060] S7. After shot blasting and pickling, the coil is subjected to silver-bright surface TA1-TA10 coil.

[0061] Furthermore, S1 specifically includes: using sponge titanium, vanadium aluminum alloy, etc. as raw materials, according to the titanium alloy element range determined by GB / T3620.1-2016TA1~TA10 titanium and titanium alloy grades and chemical composition standards, the raw materials are melted into TA1~TA10 titanium alloy ingots through a vacuum electron beam cooling hearth furnace (EB furnace), and then the ingots are melted into slabs with a thickness of 240~330mm and a width of 1600~2200mm.

[0062] Furthermore, S2 specifically includes: grinding the slab, with the six-sided milling thickness being 10 to 20 mm; grinding the four long sides along the length direction of the slab to chamfers of 40 to 60 mm, and grinding the four wide sides along the width direction of the slab to chamfers of 50 to 80 mm.

[0063] Further, S3 specifically includes: grinding the surface of the slab to be rolled to expose the metallic color, and the surface roughness Ra satisfies 0.8μm<Ra<1.6μm, preferably 0.8μm, and then coating the upper and lower surfaces of the slab to be rolled with a TA2 sheet with a thickness of 0.8-2.0mm respectively by explosive composite method, the average Vickers hardness of the TA2 sheet HV5<120, preferably HV5=100, the TA2 sheet and the titanium alloy slab need to be tightly combined to avoid oxidation of the titanium alloy slab surface during the heating process, and the use area of ​​the TA2 sheet is less than 30m 2 , without increasing processing costs.

[0064] Furthermore, in S6, during the annealing process, the bell-type furnace is kept under positive pressure with circulating argon protection to prevent oxygen from entering the furnace. The argon pressure is 2.0 to 5.0 KPa, and the circulating argon flow rate is 30 to 80 Nm 3 / h; The coils are annealed in three layers, with a spacing of 50 to 100 mm between two adjacent layers. If the spacing is too small, it will be easily affected by the radiant heat between the titanium coils, affecting the temperature uniformity. If the spacing is too large, it will interfere with the circulating gas in the furnace, resulting in excessive color difference on the surface of the titanium coil.

[0065] Furthermore, in the S6 heating stage (1), for the 3-12 mm thick hot-rolled black coils of TA1-TA5, the heating rate is 100°C / h; for the 3-12 mm thick hot-rolled black coils of TA6-TA10, the heating rate is 60°C / h;

[0066] In the S6(2) heating stage, for the 3-12 mm thick hot-rolled black coils of TA1-TA5, the heating rate is 60°C / h; for the 3-12 mm thick hot-rolled black coils of TA6-TA10, the heating rate is 30°C / h.

[0067] Furthermore, in the S6(2) heating stage, the insulation temperature of TA1 and TA2 is 570-610°C, the insulation temperature of TA3 and TA4 is 610-640°C, the insulation temperature of TA5, TA6 and TA7 is 640-670°C, and the insulation temperature of TA7, TA8, TA9 and TA10 is 670-720°C.

[0068] Furthermore, after the TA1 to TA10 plates are annealed by S6, tensile specimens are prepared and performance tests are performed in accordance with GB / T228.1-2021 to determine whether the room temperature mechanical properties of the plates meet the mechanical property requirements of GB / T3621-2023 titanium and titanium alloy plates.

[0069] By adopting the TA1-TA10 coil preparation method described in the present invention, wide hot-rolled titanium coils with a width of 1800-2400 mm, a thickness of 3-12 mm and good surface quality can be finally prepared, which solves the problem of poor surface quality of titanium alloy coils produced by the existing coil method, greatly improves product quality, reduces costs, increases the yield rate, and has good economic benefits.

[0070] The method for preparing the tape of the present invention is described in detail below in conjunction with Examples 1-2.

[0071] Example 1

[0072] This embodiment adopts the above-mentioned tape preparation method to prepare the TA1 tape, which specifically includes the following steps:

[0073] S1. Ingot smelting: Sponge titanium, vanadium aluminum alloy, etc. are used as raw materials. The raw materials are smelted into TA1 titanium alloy ingots through a vacuum electron beam cooling furnace (EB furnace). The alloy element range of the ingot meets the GB / T3620.1-2016 titanium and titanium alloy grades and chemical composition standards. Then the ingots are melted into slabs of 330 mm thick × 1800 mm wide × 6500 mm long;

[0074] S2. Slab preparation: Grind the six sides of the slab, the thickness of the six sides is 10 mm; grind the four long sides along the length direction of the slab to a chamfer of 40 mm, and grind the four wide sides along the width direction of the slab to a chamfer of 50 mm;

[0075] S3, slab coating: the surface of the slab to be rolled is polished to bare metal color, and the surface roughness is 0.8 μm, and then the upper and lower surfaces of the slab to be rolled are respectively coated with TA2 thin plates with a thickness of 0.8 mm by explosive composite method. The average Vickers hardness of the TA2 thin plates is HV5=100, and the TA2 thin plates are tightly bonded to the titanium alloy slab;

[0076] S4, slab heating: the coated slab is sent to the heating furnace for heating and rolling. After passing through the preheating zone, the first heating zone and the second heating zone of the heating furnace, the slab is kept in the 870°C soaking zone for 120 minutes. The total time in the furnace is 420 minutes, and the time in the first heating zone and the second heating zone is 300 minutes. After the insulation is completed, the slab is taken out of the furnace for rolling; wherein, when heating in the first heating zone, the temperature is from room temperature to 550°C, and the heating time is 180 minutes; when heating in the second heating zone, the temperature is 750°C, and the heating time is 120 minutes;

[0077] S5, black coil rolling: the slab is subjected to rough rolling, finish rolling and slow cooling to obtain black titanium coil, with the final rolling temperature at 730°C and the coiling temperature at 550°C;

[0078] S5 is a hot-rolled coil with a thickness of 3 mm and a width of 2000 mm after rough rolling, finish rolling and slow cooling, which specifically includes:

[0079] Rough rolling: The slab is rolled to a thickness of 40 mm through a rough rolling mill;

[0080] Finishing rolling: After rough rolling, the steel is rolled to a thickness of 3 mm by the finishing mill; the finishing inlet temperature is less than 820°C, and the strip threading speed is 1.5 m / s;

[0081] Slow cooling: After finishing rolling, the steel is coiled at a temperature of 550°C. After coiling, the steel is moved to a slow cooling zone for stack cooling at a temperature of 550°C for 12 hours. After the temperature is maintained, the steel is taken out of the furnace for air cooling. Slow cooling in a slow cooling pit is beneficial to reducing residual stress and is beneficial to subsequent uncoiling.

[0082] S6, black coil bell furnace annealing: after the rolling is completed, the coil is cooled and then subjected to recrystallization annealing in a bell furnace with electric heating and argon protection, with an annealing temperature of 570°C;

[0083] During the annealing process, the bell-type furnace maintains positive pressure circulating argon protection to prevent oxygen from entering the furnace. The argon pressure is 2.0KPa and the circulating argon flow rate is 30Nm 3 / h; The coils are annealed in three-layer stacking, with a spacing of 50mm between two adjacent layers;

[0084] The annealing temperature of the bell-type furnace adopts a gradient heating method to ensure uniform heat transfer. The annealing process includes the following three stages:

[0085] (1) Heating from room temperature to 450°C, heating rate 100°C / h, holding time 300 min, circulating argon pressure 2.0 KPa, circulating argon flow rate 30 Nm 3 / h;

[0086] (2) Heating from 450°C to 570°C, heating rate 60°C / h, holding time 600 min, circulating argon pressure 3.2 KPa, circulating argon flow rate 50 Nm 3 / h;

[0087] (3) After the insulation is completed, the temperature is gradually lowered to 450°C at a rate of 10°C / h. After 180 minutes of insulation, the heating power is turned off, the heating cover is removed, and argon gas is continuously introduced for cooling. When the average temperature in the furnace is cooled to less than 140°C, the inner cover is removed and air cooling is performed;

[0088] S7. After shot blasting and pickling, the TA1 coil with a bright silver surface is obtained. After rolling, the head and tail samples of the coil are taken for metallographic inspection. The metallographic structure of the head and tail is as follows: Figure 1-2 As shown in the figure, they are all composed of uniform equiaxed α phase, indicating that the obtained tape structure has good uniformity. Figure 3 The metallographic diagram of the TA1 tape with the same specifications as Example 1 is prepared by the existing roll-to-roll method. Figure 1-2 In comparison, it can be seen that the tissue uniformity is poor; Figure 4 and 5 The following are the scanning electron microscope images of the cross section of the TA1 titanium coil prepared in Example 1 and the scanning electron microscope images of the cross section of the TA1 tape with the same specifications as Example 1 prepared by the existing roll-to-roll method. It can be seen that the surface quality of the tape prepared in Example 1 is good, while Figure 5 There are many micro cracks in the

[0089] S8. Performance testing

[0090] After annealing, the TA1 sheet was subjected to tensile test specimen preparation and room temperature mechanical properties testing in accordance with GB / T228.1-2021. p0.2 =220MPa, Rm=330MPa, A%=40%, and the room temperature mechanical properties meet the mechanical properties requirements of GB / T3621-2023 titanium and titanium alloy plates.

[0091] Example 2

[0092] This embodiment adopts the above-mentioned tape preparation method to prepare TA10 tape, which specifically includes the following steps:

[0093] S1. Ingot smelting: Sponge titanium, vanadium aluminum alloy, etc. are used as raw materials. The raw materials are smelted into TA10 titanium alloy ingots through a vacuum electron beam cooling hearth furnace (EB furnace). The alloy element range of the ingots conforms to the GB / T3620.1-2016 titanium and titanium alloy grades and chemical composition standards. Then the ingots are smelted into slabs of 240 mm thick × 2000 mm wide × 6000 mm long.

[0094] S2. Slab preparation: Grind the six sides of the slab, the thickness of the six sides is 20 mm; grind the four long sides along the length direction of the slab to a chamfer of 60 mm, and grind the four wide sides along the width direction of the slab to a chamfer of 80 mm;

[0095] S3, slab coating: the surface of the slab to be rolled is polished to bare metal color, and the surface roughness is 1.4μm, and then the upper and lower surfaces of the slab to be rolled are respectively coated with TA2 thin plates with a thickness of 2.0mm by explosive composite method. The average Vickers hardness of the TA2 thin plates is HV5=110, and the TA2 thin plates are tightly combined with the titanium alloy slab;

[0096] S4, slab heating: the coated slab is sent to the heating furnace for heating and rolling. The slab passes through the preheating zone, the first heating zone, the second heating zone of the heating furnace and then goes to the 960°C soaking zone for 140 minutes of insulation. The total time in the furnace is 420 minutes, and the time in the first heating zone and the second heating zone is 280 minutes. After the insulation is completed, the slab is taken out of the furnace for rolling; wherein, when heating in the first heating zone, the temperature is from room temperature to 550°C, and the heating time is 120 minutes; when heating in the second heating zone, the temperature is 820°C, and the heating time is 160 minutes;

[0097] S5, Black leather coil rolling

[0098] S5, black coil rolling: the slab is subjected to rough rolling, finish rolling and slow cooling to obtain black titanium coil, with the final rolling temperature at 820°C and the coiling temperature at 600°C;

[0099] S5 is a hot-rolled coil with a thickness of 12 mm and a width of 2400 mm obtained through rough rolling, finish rolling and slow cooling, which specifically includes:

[0100] Rough rolling: The slab is rolled to a thickness of 60 mm through a rough rolling mill;

[0101] Finishing rolling: After rough rolling, the steel is rolled to a thickness of 12 mm by the finishing mill; the finishing rolling inlet temperature is less than 820°C, and the strip threading speed is 3 m / s;

[0102] Slow cooling: After finishing rolling, the steel is coiled at a temperature of 600°C. After coiling, the steel is moved to a slow cooling zone for stack cooling at a temperature of 550°C for 16 hours. After the insulation, the steel is taken out of the furnace for air cooling. Slow cooling in a slow cooling pit is beneficial to reducing residual stress and is beneficial to subsequent uncoiling.

[0103] S6, black coil bell furnace annealing: after the rolling is completed, the coil is cooled and then subjected to recrystallization annealing in a bell furnace with electric heating and argon protection, with an annealing temperature of 720°C;

[0104] During the annealing process, the bell-type furnace maintains positive pressure circulating argon protection to prevent oxygen from entering the furnace. The argon pressure is 5.0KPa and the circulating argon flow rate is 80Nm 3 / h; The coil is annealed in three layers, with a spacing of 100mm between two adjacent layers;

[0105] The annealing temperature of the bell-type furnace adopts a gradient heating method to ensure uniform heat transfer. The annealing process includes the following three stages:

[0106] (1) Heating from room temperature to 450°C, heating rate 60°C / h, holding time 480 min, circulating argon pressure 3.2 KPa, circulating argon flow rate 30 Nm 3 / h.

[0107] (2) Heating from 450°C to 720°C, heating rate 30°C / h, holding time 800 min, circulating argon pressure 5.0 KPa, circulating argon flow rate 50 Nm 3 / h;

[0108] (3) After the insulation is completed, the temperature is gradually lowered to 450°C at a rate of 30°C / h. After 240 minutes of insulation, the heating power is turned off, the heating cover is removed, and argon gas is continuously introduced for cooling. When the average temperature in the furnace is cooled to 140°C, the inner cover is removed and air cooling is performed;

[0109] S7. After shot blasting and pickling, the TA10 coil with a bright silver surface is obtained. After rolling, the head and tail samples of the coil are taken for metallographic inspection. The metallographic structure of the head and tail is as follows: Figure 6-7 As shown in the figure, they are all composed of partially recrystallized α phase + precipitates, indicating that the obtained coil structure has good uniformity. Figure 8 The metallographic image of the TA10 tape with the same specifications as Example 2 prepared by the existing roll-to-roll method shows that the uniformity of the organization is poor compared with Example 2; Fig. 9 and 10 The following are the scanning electron microscope images of the cross section of the TA10 titanium coil prepared in Example 2 and the scanning electron microscope images of the cross section of the TA10 tape with the same specifications as Example 2 prepared by the existing roll-to-roll method. It can be seen that the surface of the tape prepared in Example 2 is flat, while Figure 5 The mid-surface pits are severe;

[0110] S8. Performance testing

[0111] After annealing, the TA10 plate was prepared with tensile specimens according to GB / T228.1-2021 and the room temperature mechanical properties were tested. The results showed that Rp0.2=380MPa, Rm=524MPa, A%=27%. The room temperature mechanical properties met the mechanical properties requirements of GB / T3621-2023 for titanium and titanium alloy plates.

[0112] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for preparing TA1-TA10 tapes, characterized in that: The specific steps include: S1. Ingot smelting: The raw materials for preparing the titanium alloy are smelted into TA1-TA10 titanium alloy ingots by a vacuum electron beam cooling furnace, and then the ingots are melted into slabs; S2. Slab preparation: grinding the six sides of the slab; S3, slab coating: TA2 thin plates are coated on the upper and lower surfaces of the slab to be rolled respectively by explosive compounding; S4, slab heating: the coated slab is sent to the heating furnace for heating and rolling. The slab passes through the preheating zone, the first heating zone, the second heating zone of the heating furnace and then goes to the 870℃~960℃ soaking zone for insulation for 120~180min. The total time in the furnace is less than 440min, and the time in the first heating zone and the second heating zone is less than 360min. After the insulation is completed, the slab is taken out of the furnace for rolling; wherein, when heating in the first heating zone, the temperature is from room temperature to 550℃, and the heating time is less than 180min; when heating in the second heating zone, the temperature is 750~820℃, and the heating time is 120~180min; S5, black coil rolling: the slab is subjected to rough rolling, finish rolling and slow cooling to obtain black titanium coil, the final rolling temperature is greater than 720℃, and the coiling temperature is 550~600℃; S6. Black coil bell furnace annealing: After the rolled coil is cooled, it is subjected to recrystallization annealing in a bell furnace with electric heating and argon protection, with an annealing temperature of 570-720°C; The annealing temperature of the bell-type furnace adopts a gradient heating method. The annealing process includes the following three stages: (1) Heating from room temperature to 450°C, heating rate 60-100°C / h, holding time 300-480 min, circulating argon pressure 2.0-3.2 KPa, circulating argon flow rate 30 Nm 3 / h; (2) Heating from 450°C to 570-720°C, heating rate 30-60°C / h, holding time 600-800 min, circulating argon pressure 3.2-5.0 KPa, circulating argon flow rate 50 Nm 3 / h; (3) After the insulation is completed, the temperature is gradually lowered to 450°C at a rate of 10 to 30°C / h. After 180 to 240 minutes of insulation, the heating power is turned off, the heating cover is removed, and argon gas is continuously introduced for cooling. When the average temperature in the furnace is cooled to ≤140°C, the inner cover is removed and air cooling is performed; S7. After shot blasting and pickling, the coil is subjected to silver-bright surface TA1-TA10 coil.

2. The method for preparing TA1-TA10 tapes according to claim 1, characterized in that: S1 specifically includes: melting the raw materials into TA1-TA10 titanium alloy ingots through a vacuum electron beam cooling hearth furnace according to the titanium alloy element range determined by TA1-TA10 titanium and titanium alloy grades and chemical composition standards, and then melting the ingots into slabs with a thickness of 240-330 mm and a width of 1600-2200 mm.

3. The method for preparing TA1-TA10 tapes according to claim 2, characterized in that: S2 specifically includes: grinding the slab, with the six-sided milling thickness being 10 to 20 mm; grinding the four long sides along the length direction of the slab to chamfers of 40 to 60 mm, and grinding the four wide sides along the width direction of the slab to chamfers of 50 to 80 mm.

4. The method for preparing TA1-TA10 tapes according to claim 3, characterized in that: S3 specifically includes: grinding the surface of the slab to be rolled to a bare metal color, and the surface roughness Ra satisfies 0.8μm<Ra<1.6μm, and then coating the upper and lower surfaces of the slab to be rolled with TA2 sheets with a thickness of 0.8-2.0mm respectively by explosive composite method, the average Vickers hardness of the TA2 sheet is HV5<120, and the use area of ​​the TA2 sheet is <30m 2 .

5. The method for preparing TA1-TA10 tapes according to claim 4, characterized in that: During the annealing process, the bell-type furnace maintains positive pressure circulating argon protection to prevent oxygen from entering the furnace. The argon pressure is 2.0~5.0KPa, and the circulating argon flow rate is 30~80Nm 3 / h; the coil is annealed in three layers, with the spacing between two adjacent layers of coil being 50 to 100 mm.

6. The method for preparing TA1-TA10 tapes according to claim 5, characterized in that: S5 is a hot-rolled coil with a thickness of 3 to 12 mm and a width of 2000 to 2400 mm obtained through rough rolling, finish rolling and slow cooling, which specifically includes: Rough rolling: The slab is rolled to a thickness of 40-60 mm through a rough rolling mill; Finishing rolling: After rough rolling, the finishing mill rolls the steel to a thickness of 3-12 mm; the finishing rolling inlet temperature is less than 820°C, and the strip threading speed is 1.5-3 m / s; Slow cooling: After finishing rolling, the steel is coiled at a temperature of 550-600°C. After coiling, the steel is moved into the slow cooling zone for pile cooling at a temperature of 550°C. The steel is kept warm for 12-16 hours. After the heat preservation is completed, the steel is taken out of the furnace for air cooling.

7. The method for preparing TA1-TA10 tapes according to claim 6, characterized in that: In the S6 heating stage (1), for the 3-12 mm thick hot-rolled black coils of TA1-TA5, the heating rate is 100°C / h; for the 3-12 mm thick hot-rolled black coils of TA6-TA10, the heating rate is 60°C / h; In the S6(2) heating stage, for the 3-12 mm thick hot-rolled black coils of TA1-TA5, the heating rate is 60°C / h; for the 3-12 mm thick hot-rolled black coils of TA6-TA10, the heating rate is 30°C / h.

8. The method for preparing TA1-TA10 tapes according to claim 7, characterized in that: In the S6(2) heating stage, the insulation temperature of TA1 and TA2 is 570-610°C, the insulation temperature of TA3 and TA4 is 610-640°C, the insulation temperature of TA5, TA6 and TA7 is 640-670°C, and the insulation temperature of TA7, TA8, TA9 and TA10 is 670-720°C.

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