A short process preparation method of ultra-wide TA15 (class B) titanium alloy long plate

Abstract

The application discloses a short-process preparation method of an ultra-wide TA15 (B type) titanium alloy long-thick plate, and the method comprises the following steps: firstly, performing gradient temperature heating treatment on TA15 (B type) titanium alloy slab after coating the surface of the slab with an anti-oxidation coating; secondly, rolling in one heating cycle and introducing a spraying system; thirdly, performing rapid air cooling after reciprocating straightening; and fourthly, performing air cooling after reciprocating straightening after heat treatment. In the application, the surface of the slab is coated with an anti-oxidation coating, a single-heating-cycle deformation combined with reversing rolling is adopted, the rolling pass number and the deformation rate are controlled, the intermediate return-to-furnace temperature compensation is increased, and the spraying system is introduced, so that near-constant-temperature rolling is realized, high-performance plate is obtained, the surface quality of the plate is improved, and the plate has high size precision and good plate shape, and the production process is shortened and the cost is saved.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of titanium alloy plate preparation, and particularly relates to a short-process preparation method of an ultra-wide TA15 (B type) titanium alloy long-thick plate. BACKGROUND

[0002] Titanium and titanium alloy have the advantages of small density, high specific strength, corrosion resistance, etc. In recent years, China's titanium industry has developed rapidly, and the preparation and processing technology of titanium and titanium alloy has been continuously improved. Titanium and titanium alloy plates are also widely used in the fields of aviation, aerospace, shipbuilding, petrochemical industry, electronics, medical treatment, ocean engineering, and refrigeration engineering. TA15 titanium alloy belongs to a medium-strength titanium alloy, and is particularly suitable for manufacturing key load-bearing components such as large integral frames, beams, and joints of an airplane, and is widely used in the field of aviation and aerospace.

[0003] At present, with the requirement of cost control in the field of aviation and aerospace, the trend of using thick-gauge plates to replace forgings to save costs is becoming more and more obvious, and the width and length ranges required by the plates are both at a new high level. However, it is still difficult to meet the multiple requirements of internal organization morphology, high dimensional accuracy, and good surface quality at the same time. There are two patents for the production of TA15 wide plates: the patent with the publication number CN111085546A, “Preparation method of super-large wide alloy plate”, adopts a 2800mm four-high reversible rolling mill, and through hot rolling and reversing rolling, and beta quenching process, a super-large wide TA15 titanium alloy plate with a size of 1.2mm×1200mm×2500mm is obtained. The patent with the publication number CN106925612A, “Processing method of high dimensional accuracy TA15 titanium alloy wide medium-thick plate”, adopts a three-fire rolling method with large deformation reversing rolling in the first two fires and small deformation in the last fire. Since the plate is formed by three-fire rolling, the yield rate is relatively low, and in order to complete the multiple reversing rolling in the plate rolling process, the shearing and cutting process is required. The above factors affect the size of the finished plate. When the maximum width of the finished plate is 2500mm, the length is only 3250mm; when the maximum length is 4995mm, the width is only 1500mm.

[0004] At present, in the case of width expansion of TA15 titanium alloy plates, the length dimension is difficult to further break through, especially when the width is more than 2000mm, it is difficult to obtain a plate with a length of more than 4000mm, and it is also difficult to consider the morphology and organization of TA15 titanium alloy plates to achieve the best comprehensive performance matching of equiaxed state, high plate size accuracy, and good surface quality.

[0005] The equipment processing capacity requirement is higher in the wide plate production process, at present, the temperature difference of the head and tail and the width direction is increased due to the temperature drop loss in the rolling process, which causes the great difference of the plate structure and performance; in addition, the wider the plate is, the more difficult the plate shape is controlled, and the higher the rolling precision requirement is, and the plate shape correction is more difficult. SUMMARY

[0006] The technical problem to be solved by the present application is to provide a short process preparation method of ultra-wide TA15 (B type) titanium alloy long thick plate, aiming at the above-mentioned deficiencies of the prior art. The method coats the surface of the slab with an anti-oxidation coating, uses gradient heating treatment to control the alloy microstructure morphology, avoids the formation of a thick oxidation layer, and uses single-fire deformation combined with reversing constant temperature rolling method, combined with control of rolling pass number and deformation rate, increases intermediate recycling temperature compensation and introduces a spraying system measure, realizes near constant temperature rolling, obtains high performance plate, improves the surface quality of the plate, and at the same time, combined with AGC thickness automatic control, shape control in the rolling process and large pressure of post-rolling heat rolling mill shape correction and straightening machine shape correction processing, so as to obtain plate with high dimensional accuracy and good shape, solve the problem of great difference of plate structure and performance and difficult shape correction in the prior art.

[0007] To solve the above technical problems, the technical scheme adopted by the present application is as follows: a short process preparation method of ultra-wide TA15 (B type) titanium alloy long thick plate, characterized in that the method comprises the following steps:

[0008] Step one, coating the surface of the TA15 (B type) titanium alloy slab with an anti-oxidation coating, then performing gradient temperature heating treatment; the thickness of the TA15 (B type) titanium alloy slab is 220mm-260mm, the width is 1200mm-1600mm, and the length is 1000mm-2000mm;

[0009] Step two, the TA15 (B type) titanium alloy plate in step one is subjected to one-pass rolling, and a spraying system is introduced for temperature control during the rolling process, to obtain the TA15 (B type) titanium alloy plate; the one-pass rolling is reversing rolling, and the specific process is as follows: first, the TA15 (B type) titanium alloy plate after the heating treatment is subjected to pre-reversing rolling, the pass deformation rate of the pre-reversing rolling is 5% to 12%, the pass number is 3 to 5 passes, and the rolling speed is 3 m / s to 4 m / s, to obtain a first rolling plate blank with a thickness of 160 mm to 200 mm and a width of 1600 mm to 2000 mm; the first rolling plate blank is subjected to online reheat temperature compensation at 920 ℃ to 940 ℃, and then subjected to two-pass reversing rolling, wherein the pass deformation rate of the first rolling pass is 5% to 20%, the pass number is 5 to 8 passes, and the rolling speed is 3 m / s to 4 m / s; after the first-pass reversing rolling, a second rolling plate blank with a thickness of 80 mm to 100 mm and a width of 1600 mm to 2000 mm is obtained; the second rolling plate blank is subjected to online reheat temperature compensation at 920 ℃ to 940 ℃, and then subjected to second-pass reversing rolling, the pass deformation rate of the second rolling pass is 8% to 20%, the pass number is 5 to 6 passes, and the rolling speed is 3 m / s to 4 m / s; the rolling directions of the two rolling passes are the same, and AGC thickness automatic control is adopted during the rolling process, to obtain the TA15 (B type) titanium alloy plate with a thickness of 30 mm to 50 mm, a width of 1600 mm to 2000 mm, and a length of 4000 mm to 7000 mm, and the unevenness of the TA15 (B type) titanium alloy plate is less than 3 mm / m, and the spacing between the platforms of each corner is not greater than 5 mm.

[0010] Step three, the TA15 (B type) titanium alloy plate obtained in step two is sequentially and rapidly subjected to 2 to 4 passes of reciprocating straightening through a rolling mill, and subjected to 6 to 8 passes of reciprocating straightening through a straightening machine, and then rapidly air-cooled, to obtain the straightened TA15 (B type) titanium alloy plate.

[0011] Step four, the straightened TA15 (B type) titanium alloy plate obtained in step three is subjected to heat treatment, and then subjected to 6 to 8 passes of reciprocating straightening through a straightening machine, and then air-cooled to room temperature, to obtain the ultra-wide TA15 (B type) titanium alloy long-thick plate with a thickness of 30 mm to 50 mm, a width of 1600 mm to 2000 mm, and a length of 4000 mm to 7000 mm.

[0012] The present application is a short process preparation method of a super-wide TA15 (B type) titanium alloy long thick plate, which comprises the following steps: (1) coating a Ti-89 anti-oxidation coating on the surface of a TA15 (B type) titanium alloy slab in a cross manner, and the last coating is performed along the rolling direction; (2) heating treatment at a temperature of 920-940 DEG C for 4-6 hours; (3) rolling; (4) spraying in the whole rolling process; (5) intermediate re-melting heating; (6) reversing rolling; (7) intermediate re-melting heating; (8) rolling; (9) online straightening; and (10) finished product heat treatment. In the preparation process, the TA15 (B type) titanium alloy slab is first coated with an anti-oxidation coating on the surface to improve the heat preservation and anti-oxidation effect, improve the surface quality of the plate, and adopt gradient heating by cooling furnace charging, which can fully heat the slab and prevent the internal organization of the slab from changing too much due to long-time high-temperature heating below the phase transition point, thereby effectively preventing the formation of a thick oxidation layer during high-temperature heating. By adopting the method of "single fire deformation" + "reversing rolling", the uniformity of the microstructure and the consistency of the performance of the plate thickness section are ensured, and the "near-constant temperature" rolling is achieved by combining the timely intermediate re-melting temperature compensation measures. In addition, the spraying system is introduced in the rolling process to reduce the temperature of the work roll and the rolled slab, so as to realize low-temperature rolling and avoid excessive temperature rise of the slab after being pressed by the roll, which can prevent the change of the slab organization due to temperature rise, thereby ensuring the uniformity of the plate temperature during rolling and the uniformity of the subsequent product organization and performance, effectively strengthening the plate and improving the strength performance of the plate. At the same time, the AGC thickness automatic control, shape control during rolling, and post-rolling heat rolling shape correction and straightening machine shape correction treatment are combined, so as to obtain high dimensional accuracy and good shape. By air cooling after straightening to speed up the cooling speed, the straightening plate shape can be fixed within a reasonable execution range, and the growth of the grain size in the plate is inhibited. Finally, the plate performance and dimensional tolerance of the super-wide TA15 (B type) titanium alloy long thick plate prepared by the present application meet the standard requirements, and the obvious cracking phenomenon of titanium alloy caused by temperature drop in the traditional process is reduced, thereby reducing the polishing amount in the later stage, shortening the production process, and saving the production cost.

[0013] The short process preparation method of a super-wide TA15 (B type) titanium alloy long thick plate comprises the following steps: (1) coating a Ti-89 anti-oxidation coating on the surface of a TA15 (B type) titanium alloy slab in a cross manner, and the last coating is performed along the rolling direction; (2) heating treatment at a temperature of 920-940 DEG C for 4-6 hours. The TA15 (B type) titanium alloy slab is coated with an anti-oxidation coating to play a protective role, so as to avoid the formation of a thick anti-oxidation coating on the surface of the slab after heat treatment. At the same time, the cross coating is avoided, and the last coating is performed along the rolling direction, so that the anti-oxidation coating plays a heat preservation role during rolling, effectively prevents the slippage of the slab and the falling of the anti-oxidation coating during rolling, and improves the surface quality of the plate after rolling.

[0014] The short process preparation method of the super-wide TA15 (B type) titanium alloy long-thick plate has the characteristics that the opening rolling temperature of the one-time rolling in the step two is not less than 900 DEG C, the final rolling temperature is not less than 780 DEG C, the total deformation rate of the pre-reversing rolling is 20% to 30%, the total deformation rate of the first rolling process in the reversing rolling of the two rolling processes is 40% to 55%, and the total deformation rate of the second rolling process is 50% to 65%. The opening rolling temperature and the final rolling temperature of the one-time rolling are limited, on the one hand, the rolling deformation is carried out in the specified processing temperature range, the high finished product performance is obtained, the product performance stability in the mass production is ensured, on the other hand, the plate material is deformed at a higher temperature, the plate surface quality is improved, the plate surface grinding amount is reduced, the yield is improved, and the production cycle is shortened. Meanwhile, the total deformation rate of the three times of rolling is controlled to obtain better comprehensive performance.

[0015] The short process preparation method of the super-wide TA15 (B type) titanium alloy long-thick plate has the characteristics that the temperature of the TA15 (B type) titanium alloy plate before the straightening in the step three is not less than 780 DEG C, the temperature after the straightening is not less than 600 DEG C, and the speed of the reciprocating straightening is 1 m / s to 2 m / s. The plate width of the TA15 (B type) titanium alloy long-thick plate prepared based on the application is large, so the temperature before and after the straightening is controlled, the heat is wasted by using the waste heat for the rapid reciprocating straightening, the reciprocating straightening is carried out by using the high waste heat after the hot rolling and the large pressure provided by the rolling mill, the straightening efficiency is improved, then the required flatness and the small residual stress are obtained by the reciprocating straightening of the straightening machine, so that the plate shape of the super-wide TA15 (B type) titanium alloy plate is ensured.

[0016] The short process preparation method of the super-wide TA15 (B type) titanium alloy long-thick plate has the characteristics that the temperature of the TA15 (B type) titanium alloy plate before the straightening in the step three is not less than 780 DEG C, the temperature after the straightening is not less than 600 DEG C, and the speed of the reciprocating straightening is 1 m / s to 2 m / s. The plate width of the TA15 (B type) titanium alloy long-thick plate prepared based on the application is large, so the temperature before and after the straightening is controlled, the heat is wasted by using the waste heat for the rapid reciprocating straightening, the reciprocating straightening is carried out by using the high waste heat after the hot rolling and the large pressure provided by the rolling mill, the straightening efficiency is improved, then the required flatness and the small residual stress are obtained by the reciprocating straightening of the straightening machine, so that the plate shape of the super-wide TA15 (B type) titanium alloy plate is ensured.

[0017] Compared with the prior art, the application has the following advantages:

[0018] 1. The cross-oxidation protective coating is coated on the surface of the TA15 (B type) titanium alloy plate before the heat treatment, and the last coating is carried out along the rolling direction, so that the thick oxidation layer is effectively prevented from appearing after the plate blank is heated, the oxidation protective coating also plays a heat preservation role in the rolling process, the plate blank slipping phenomenon and the oxidation protective coating falling phenomenon in the rolling process are effectively avoided, the plate surface quality is effectively improved, the surface grinding amount in the grinding process is reduced, and the production cycle is shortened.

[0019] 2、The application adjusts the heating system, adopts the gradient heating treatment of cooling furnace loading and temperature rising, promotes the full heating of the slab, avoids the internal organization morphology transformation of the slab caused by long time high temperature heating, and effectively prevents the thick oxidation layer caused by high temperature heating.

[0020] 3、The application effectively controls the processing window, adopts the method of "single fire deformation" + "reversing rolling", controls the rolling pass number and the maximum pass deformation rate, ensures the uniformity of the microstructure and the consistency of the performance on the thickness section of the plate, combines the timely online intermediate reheat temperature compensation measures to achieve "near constant temperature" rolling, ensures the uniformity of the plate temperature in the rolling process and the uniformity of the subsequent product organization performance, ensures the plate deformation at a higher temperature, improves the plate surface quality, reduces the plate surface grinding amount, and improves the yield.

[0021] 4、The application introduces a spraying system in the rolling process, reduces the temperature of the work roll of the rolling equipment and the rolled slab, realizes low temperature rolling, avoids the excessive temperature rise phenomenon of the slab after the plastic deformation of the rolling roll, causes the slab organization morphology to change due to temperature rise, and effectively strengthens the plate and improves the strength performance of the plate.

[0022] 5、The application sequentially carries out the rolling mill straightener and reciprocating straightening after rolling, fully utilizes the high residual temperature of the plate after rolling, combines the AGC thickness automatic control, shape control in the rolling process, and the large pressure of the rolling mill shape correction after rolling, and the straightening machine shape correction processing, thereby obtaining high dimensional accuracy and good shape, avoiding repeated shape correction processing of the wide plate; at the same time, air cooling is adopted to accelerate the cooling speed, ensure that the shape of the plate after straightening can be fixed in a reasonable execution range, and inhibit the growth of the grain size in the plate.

[0023] 6、The width of the ultra-wide TA15 (B type) titanium alloy long plate prepared by the application is up to 1600mm-2000mm, the length is up to 4000mm-7500mm, the surface quality of the long plate is good, the dimensional tolerance meets the required range, the internal defects of the long plate are few, the stability is good, the yield is greatly improved, at the same time, the obvious cracking phenomenon of titanium alloy caused by temperature drop in the traditional process is reduced, thereby reducing the later polishing amount, shortening the production process, and saving the production cost.

[0024] The technical solutions of the application will be further described in detail through the drawings and examples. BRIEF DESCRIPTION OF DRAWINGS

[0025] Figure 1 The metallographic structure diagram (200x) of the ultra-wide TA15 (B type) titanium alloy long plate prepared for the embodiment 1 of the application.

[0026] Figure 2The metallographic structure diagram (200x) of the ultra-wide TA15 (B type) titanium alloy long-thick plate prepared in the embodiment 2 of the present application.

[0027] Figure 3 The metallographic structure diagram (200x) of the ultra-wide TA15 (B type) titanium alloy long-thick plate prepared in the embodiment 3 of the present application. DETAILED DESCRIPTION

[0028] Embodiment 1

[0029] The present embodiment comprises the following steps:

[0030] Step one, the TA15 (B type) titanium alloy slab is cross-coated with Ti-89 anti-oxidation coating on the surface, and the last coating is performed along the rolling direction, and then a cooling furnace charging gradient heating treatment is performed: first heated to 780℃ for 2h, and then heated to 920℃ for 4h; the thickness of the TA15 (B type) titanium alloy slab is 220mm, the width is 1200mm, and the length is 1000mm;

[0031] Step two, the TA15 (B type) titanium alloy slab after the heating treatment in step one is subjected to one-pass rolling, and a temperature control is introduced in the rolling process by using a spraying system, to obtain TA15 (B type) titanium alloy plate; the one-pass rolling is reversing rolling, and the opening rolling temperature is 908℃ and the final rolling temperature is 805℃, and the specific process is as follows: the TA15 (B type) titanium alloy slab after the heating treatment is first subjected to 3-pass pre-reversing rolling, and the pass deformation rates of the pre-reversing rolling are 9%, 10%, and 11.1% in sequence, the rolling speed is 3m / s, the total deformation rate is 25%, and a first rolling slab with a thickness of 160mm and a width of 1600mm is obtained; the first rolling slab is subjected to online re-furnace temperature compensation at 920℃, and then subjected to two-pass reversing rolling, wherein the pass deformation rates of the first rolling pass are 10.6%, 12.6%, 14.4%, 14.0%, and 13.0% in sequence, the pass number is 5, the total deformation rate of the first rolling pass is 50%, the rolling speed is 3m / s, and a second rolling slab with a thickness of 80mm and a width of 1600mm is obtained after the first-pass reversing rolling; the second rolling slab is subjected to online re-furnace temperature compensation at 920℃, and then subjected to second-pass reversing rolling, and the pass deformation rates of the second rolling pass are 16.3%, 16.4%, 17.9%, 19.6%, and 18.9% in sequence, the total deformation rate is 63%, the pass number is 5, the rolling speed is 3m / s, and the rolling directions of the two rolling passes are the same; AGC thickness automatic control is adopted in the rolling process, to obtain TA15 (B type) titanium alloy plate with a thickness of 30mm, a width of 1600mm, and a length of 4000mm, and the plate difference of the plate after rolling is controlled within the range of 0.35mm;

[0032] Step three, the TA15 (B type) titanium alloy plate obtained in step two is quickly passed through a rolling mill for 2 passes of reciprocating straightening, and is passed through a 11-roller straightening machine for 6 passes of reciprocating straightening, and the speed of the reciprocating straightening is 1 m / s, and then rapid air cooling is performed, to obtain a straightened TA15 (B type) titanium alloy plate with a thickness of 30 mm, a width of 1600 mm, and a length of 4000 mm; the temperature of the TA15 (B type) titanium alloy plate before straightening is 800℃, and the temperature after straightening is 620℃;

[0033] Step four, the straightened TA15 (B type) titanium alloy plate obtained in step three is subjected to heat treatment, the temperature of the heat treatment is 800℃, the holding time is 70 min, air cooling is performed after annealing to room temperature, and then 6 passes of reciprocating straightening are performed through a straightening machine, and then air cooling is performed to room temperature, to obtain an ultra-wide TA15 (B type) titanium alloy long-thick plate with a thickness of 30 mm, a width of 1600 mm, and a length of 4000 mm.

[0034] Figure 1 The metallographic structure diagram (200x) of the ultra-wide TA15 (B type) titanium alloy long-thick plate prepared in this embodiment is shown in Figure 1 It can be seen that the microstructure of the ultra-wide TA15 (B type) titanium alloy long-thick plate is a uniform structure processed in the α+β two-phase region, the original β grains are fully broken, there is no continuous and flat grain boundary α phase, and the microstructure morphology at different positions is basically consistent.

[0035] Through detection, the room temperature tensile strength of the ultra-wide TA15 (B type) titanium alloy long-thick plate prepared in this embodiment is 990 MPa-1010 MPa, the yield strength is 915 MPa-935 MPa, the elongation after fracture is 16%-19%, the reduction of area is 48%-50%, the impact toughness value is 55 J / cm 2 -60 J / cm 2 , the fracture toughness is 70 MPa·m 1 / 2 -80 MPa·m 1 / 2 , the 500℃ high temperature tensile strength is 690 MPa-710 MPa, the yield strength is 530 MPa-570 MPa, the elongation after fracture is 18%-22%, the reduction of area is 70%-80%, the 500℃ endurance satisfies 50 h, and all the properties meet the requirements of GJB 2505A-2018 "Titanium and Titanium Alloy Plate and Strip Specification for Aerospace".

[0036] In summary, the metallographic structure of the ultra-wide TA15 (B type) titanium alloy long-thick plate prepared in this embodiment meets the organizational requirements of TA15 (B type) titanium alloy, and the mechanical properties are excellent.

[0037] Example 2

[0038] The embodiment comprises the following steps:

[0039] Step one, the surface of TA15 (B type) titanium alloy slab is cross coated with Ti-89 anti-oxidation coating, and the last coating is along the rolling direction, then gradient heating treatment is carried out by cooling furnace charging: first heating to 800℃ for 2h, then heating to 920℃ for 6h; the thickness of the TA15 (B type) titanium alloy slab is 260mm, the width is 1600mm, and the length is 2000mm;

[0040] Step two, the TA15 (B type) titanium alloy slab after heating treatment in step one is rolled once, and temperature control is introduced in the rolling process by spraying system, to obtain TA15 (B type) titanium alloy plate; the once rolling is reversing rolling, and the opening rolling temperature is 920℃ and the final rolling temperature is 830℃, and the specific process is as follows: the TA15 (B type) titanium alloy slab after heating treatment is first rolled by 5 passes of pre-reversing rolling, the pass deformation rate of pre-reversing rolling is 5.4%, 6.2%, 5.6%, 5.5%, 5.3% in turn, the rolling speed is 4m / s, and the total deformation rate is 23%, to obtain a first rolling slab with a thickness of 200mm, a width of 2000mm; the first rolling slab is reheated for temperature compensation at 940℃, and then two-pass reversing rolling is carried out, wherein the pass deformation rate of the first rolling pass is 6.7%, 7.0%, 7.1%, 7.2%, 7.1%, 7.2%, 7.4%, 6.9% in turn, the pass number is 8, the total deformation rate of the first rolling pass is 50%, the rolling speed is 4m / s, and the second rolling slab with a thickness of 100mm, a width of 2000mm is obtained after the first-pass reversing rolling, the second rolling slab is reheated for temperature compensation at 940℃, and then the second-pass reversing rolling is carried out, the pass deformation rate of the second rolling pass is 8.0%, 10.9%, 12.2%, 13.9%, 11.3%, 9.1% in turn, the total deformation rate is 50%, the pass number is 6, and the rolling speed is 4m / s, and the rolling directions of the two rolling passes are the same, AGC thickness automatic control is adopted in the rolling process, to obtain TA15 (B type) titanium alloy plate with a thickness of 50mm, a width of 2000mm, and a length of 7000mm, and the plate difference of the plate after rolling is controlled within 0.55mm;

[0041] Step three, the TA15 (B type) titanium alloy plate obtained in step two is sequentially and rapidly passed through the rolling mill for 4 passes of reciprocating straightening, and passed through the 11-roller straightening machine for 6 passes of reciprocating straightening, and the speed of the reciprocating straightening is 2m / s, and then rapid air cooling is carried out, to obtain straightened TA15 (B type) titanium alloy plate with a thickness of 50mm, a width of 2000mm, and a length of 7000mm; the temperature of the TA15 (B type) titanium alloy plate before straightening is 830℃, and the temperature after straightening is 650℃.

[0042] Step four, the TA15 (B type) titanium alloy plate obtained in step three is subjected to heat treatment, the temperature of the heat treatment is 850 DEG C, the holding time is 120 min, after annealing, air cooling is carried out to room temperature, then 8 passes of reciprocating straightening is carried out through a straightening machine, and then air cooling is carried out to room temperature, thereby obtaining the ultra-wide TA15 (B type) titanium alloy long plate with a thickness of 50 mm, a width of 2000 mm and a length of 7000 mm.

[0043] Figure 2 The metallographic structure diagram (200x) of the ultra-wide TA15 (B type) titanium alloy long plate prepared in the embodiment is shown in Figure 2. Figure 2 It can be seen that the microstructure of the ultra-wide TA15 (B type) titanium alloy long plate is a uniform structure processed in the α+β two-phase region, the original β grains are fully broken, there is no continuous and flat grain boundary α phase, and the microstructure morphologies at different positions are basically consistent.

[0044] Through detection, the room temperature tensile strength of the ultra-wide TA15 (B type) titanium alloy long plate prepared in the embodiment is 975 MPa-995 MPa, the yield strength is 895 MPa-920 MPa, the elongation after fracture is 16%-20%, the reduction of area is 46%-50%, the impact toughness value is 58 J / cm 2 -63 J / cm 2 , the fracture toughness is 79 MPa·m 1 / 2 -80 MPa·m 1 / 2 , the 500 DEG C high temperature tensile strength is 675 MPa-700 MPa, the yield strength is 520 MPa-550 MPa, the elongation after fracture is 17%-22%, the reduction of area is 72%-80%, the 500 DEG C endurance satisfies 50 h, and all the properties meet the requirements of GJB 2505A-2018 "Titanium and Titanium Alloy Plate and Strip Specification for Aviation".

[0045] In summary, the metallographic structure of the ultra-wide TA15 (B type) titanium alloy long plate prepared in the embodiment meets the organization requirements of TA15 (B type) titanium alloy, and the mechanical properties are excellent.

[0046] Embodiment 3

[0047] The embodiment includes the following steps:

[0048] Step one, a Ti-89 anti-oxidation coating is cross-coated on the surface of a TA15 (B type) titanium alloy slab, and the last coating is carried out along the rolling direction, and then gradient temperature heating treatment is carried out by cooling the furnace: first, heating to 800 DEG C for 2 h, and then heating to 940 DEG C for 5 h; the thickness of the TA15 (B type) titanium alloy slab is 240 mm, the width is 1400 mm, and the length is 1500 mm;

[0049] Step two, the TA15 (B type) titanium alloy plate blank after heating treatment in step one is rolled by one pass, and a spraying system is introduced for temperature control during rolling, to obtain TA15 (B type) titanium alloy plate; the one pass rolling is reversing rolling, and the opening rolling temperature is 915℃, and the final rolling temperature is 820℃, and the specific process is as follows: first, the TA15 (B type) titanium alloy plate blank after heating treatment is subjected to 4-pass pre-reversing rolling, and the pass deformation rate of the pre-reversing rolling is 5.7%, 6.5%, 5.9%, and 5.8% in turn, the rolling speed is 4m / s, the total deformation rate is 25%, and a first rolling plate blank with a thickness of 180mm and a width of 1800mm is obtained, the first rolling plate blank is subjected to online reheat temperature compensation at 940℃, and then two-pass reversing rolling is carried out, wherein the pass deformation rate of the first rolling pass is 7.1%, 8.2%, 10.3%, 11.5%, 12.2%, and 10.9% in turn, the pass number is 6, the total deformation rate of the first rolling pass is 47%, the rolling speed is 4m / s, and after the first-pass reversing rolling, a second rolling plate blank with a thickness of 90mm and a width of 1800mm is obtained, the second rolling plate blank is subjected to online reheat temperature compensation at 940℃, and then the second-pass reversing rolling is carried out, the pass deformation rate of the second rolling pass is 10%, 11.1%, 15.3%, 19.7%, and 18.4% in turn, the total deformation rate is 50%, the pass number is 5, the rolling speed is 4m / s, and the rolling directions of the two passes are the same, AGC thickness automatic control is adopted during rolling, and TA15 (B type) titanium alloy plate with a thickness of 40mm, a width of 1800mm, and a length of 5700mm is obtained, and the plate difference of the plate after rolling is controlled within 0.42mm;

[0050] Step three, the TA15 (B type) titanium alloy plate obtained in step two is sequentially and quickly subjected to 4-pass reciprocating straightening through a rolling mill and 6-pass reciprocating straightening through an 11-roller straightening machine, and the speed of the reciprocating straightening is 2m / s, and then rapid air cooling is carried out, to obtain straightened TA15 (B type) titanium alloy plate with a thickness of 40mm, a width of 1800mm, and a length of 5700mm; the temperature of the TA15 (B type) titanium alloy plate before straightening is 820℃, and the temperature after straightening is 640℃;

[0051] Step four, the straightened TA15 (B type) titanium alloy plate obtained in step three is subjected to heat treatment, the heat treatment temperature is 830℃, the holding time is 100min, air cooling is carried out after annealing to room temperature, then 8-pass reciprocating straightening is carried out through a straightening machine, and then air cooling is carried out to room temperature, to obtain ultra-wide TA15 (B type) titanium alloy long-thick plate with a thickness of 40mm, a width of 1800mm, and a length of 5700mm.

[0052] Figure 3 The metallographic structure chart (200x) of the ultra-wide TA15 (B type) titanium alloy long-thick plate prepared in the embodiment is shown in Figure 1. Figure 3 It can be seen that the microstructure of the ultra-wide TA15 (B type) titanium alloy long-thick plate is a uniform structure processed through the α+β two-phase zone, the original β grains are fully broken, there is no continuous and flat grain boundary α phase, and the microstructure morphologies at different positions are basically consistent.

[0053] Through detection, the room temperature tensile strength of the ultra-wide TA15 (B type) titanium alloy long-thick plate prepared in the embodiment is 980 MPa-1000 MPa, the yield strength is 905 MPa-930 MPa, the elongation after fracture is 17%-20%, the reduction of area is 48%-52%, the impact toughness value is 57 J / cm 2 -62 J / cm 2 , the fracture toughness is 75 MPa·m 1 / 2 -82 MPa·m 1 / 2 , the 500℃ high temperature tensile strength is 685 MPa-705 MPa, the yield strength is 525 MPa-550 MPa, the elongation after fracture is 19%-24%, the reduction of area is 70%-80%, the 500℃ endurance satisfies 50 h, and all the performances satisfy the requirements of GJB 2505A-2018 “Titanium and Titanium Alloy Plate and Strip Specification for Aviation”.

[0054] In summary, the metallographic structure of the ultra-wide TA15 (B type) titanium alloy long-thick plate prepared in the embodiment satisfies the organization requirements of the TA15 (B type) titanium alloy, and the mechanical properties are excellent.

[0055] The above is only a preferred embodiment of the present application, and does not limit the present application in any way. Any simple modification, change and equivalent change made according to the technical essence of the present application to the above embodiment are still within the protection scope of the technical solution of the present application.

Claims

1. A short process for the production of an ultra-wide TA15 (Class B) titanium alloy plate, characterized in that, The method comprises the following steps: Step one, the TA15 (B type) titanium alloy slab surface is coated with an oxidation-resistant coating, and then gradient heating treatment is carried out by cooling furnace charging; the thickness of the TA15 (B type) titanium alloy slab is 220mm-260mm, the width is 1200mm-1600mm, and the length is 1000mm-2000mm; Step two, the TA15 (B type) titanium alloy slab after the heating treatment in step one is subjected to one-pass rolling, and a temperature control is introduced in the rolling process by using a spraying system, thereby obtaining TA15 (B type) titanium alloy plate; the one-pass rolling is reversing rolling, and the specific process is as follows: first, the TA15 (B type) titanium alloy slab after the heating treatment is subjected to pre-reversing rolling, the pass deformation rate of the pre-reversing rolling is 5%-12%, the pass number is 3-5 passes, and the rolling speed is 3m / s-4m / s, thereby obtaining a first rolling slab with a thickness of 160mm-200mm and a width of 1600mm-2000mm; the first rolling slab is subjected to online reheat temperature compensation at 920°C-940°C, and then two-pass reversing rolling is carried out, wherein the pass deformation rate of the first rolling pass is 5%-20%, the pass number is 5-8 passes, and the rolling speed is 3m / s-4m / s; after the first rolling pass, a second rolling slab with a thickness of 80mm-100mm and a width of 1600mm-2000mm is obtained; the second rolling slab is subjected to online reheat temperature compensation at 920°C-940°C, and then second-pass reversing rolling is carried out; the pass deformation rate of the second rolling pass is 8%-20%, the pass number is 5-6 passes, and the rolling speed is 3m / s-4m / s; the rolling directions of the two rolling passes are the same; AGC thickness automatic control is adopted in the rolling process, thereby obtaining TA15 (B type) titanium alloy plate with a thickness of 30mm-50mm, a width of 1600mm-2000mm, and a length of 4000mm-7000mm; the unevenness of the TA15 (B type) titanium alloy plate is less than 3mm / m, and the spacing between the platforms of each angle is not greater than 5mm; Step three, the TA15 (B type) titanium alloy plate obtained in step two is sequentially and rapidly subjected to 2-4-pass reciprocating straightening by a rolling mill and 6-8-pass reciprocating straightening by a straightening machine, and then rapid air cooling is carried out, thereby obtaining straightened TA15 (B type) titanium alloy plate; Step four, the straightened TA15 (B type) titanium alloy plate obtained in step three is subjected to heat treatment, and then subjected to 6-8-pass reciprocating straightening by a straightening machine, and then air cooling is carried out to room temperature, thereby obtaining ultra-wide TA15 (B type) titanium alloy long-thick plate with a thickness of 30mm-50mm, a width of 1600mm-2000mm, and a length of 4000mm-7000mm.

2. The short process preparation method of the ultra-wide TA15 (Class B) titanium alloy plate according to claim 1, characterized in that, In step one, the TA15 (B type) titanium alloy slab surface is cross-coated with Ti-89 oxidation-resistant coating, and the last coating is carried out along the rolling direction; the heating treatment temperature is 920°C-940°C, and the holding time is 4h-6h.

3. The short process preparation method of ultra-wide TA15 (Class B) titanium alloy plate according to claim 1, characterized in that, The open rolling temperature in step two is not less than 900℃, the finish rolling temperature is not less than 780℃, the total deformation rate of the pre-reversing rolling is 20% to 30%, in the reversing rolling of the two rolling processes, the total deformation rate of the first rolling process is 40% to 55%, and the total deformation rate of the second rolling process is 50% to 65%.

4. The short process preparation method of ultra-wide TA15 (Class B) titanium alloy plate according to claim 1, characterized in that, In step three, the temperature of the TA15 (class B) titanium alloy plate before straightening is not less than 780℃, the temperature after straightening is not less than 600℃, and the speed of the reciprocating straightening is 1m / s to 2m / s.

5. The short process preparation method of ultra-wide TA15 (Class B) titanium alloy plate according to claim 1, characterized in that, In step four, the temperature of the heat treatment is 800℃ to 850℃, the holding time is 70min to 120min, and the air cooling after annealing is to room temperature.

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