Rolling process of Ti / Al / Mg / Al / Ti composite plate

Abstract

The application relates to a rolling process of a Ti / Al / Mg / Al / Ti composite plate and belongs to the technical field of rolling processes. The rolling process comprises the following steps: raw material preparation, including 6061 aluminum alloy plates, Ti-6Al-4V titanium alloy plates and Mg-Zn-Zr magnesium alloy plates; after surface treatment, the plates are sequentially laminated according to the interval alternating order of Ti+Al+Mg+Al+Ti and then are uniformly preheated in a resistance furnace; the laminated plates after preheating are subjected to hot rolling deformation; then, heat diffusion treatment is carried out to obtain heat-treated plates; the heat-treated plates are subjected to asynchronous cold rolling deformation to obtain asynchronous cold rolling deformation plates; the asynchronous cold rolling deformation plates are subjected to cross cold rolling treatment to obtain Ti / Al / Mg / Al / Ti composite plates with good interface bonding. The method can improve the interface bonding force of the Ti / Al / Mg / Al / Ti composite plates and lays a foundation for the engineering application of the composite plates.

Description

Technical Field

[0001] This invention belongs to the field of rolling technology, and specifically relates to a hot rolling, asynchronous and cross cold rolling process for Ti / Al / Mg / Al / Ti composite plates. Background Technology

[0002] With the increasing demand for lightweight materials in industries such as transportation and aerospace, magnesium alloys have become a very important new type of green lightweight structural material. However, the disadvantages of magnesium alloys in terms of corrosion resistance, strength, stiffness, and surface modifiability severely restrict their widespread application. Magnesium-aluminum composite plates have significantly improved the defects of magnesium alloys in terms of plasticity and corrosion resistance, but their mechanical strength is still relatively low. Therefore, high-strength and high-stiffness titanium alloys can be used on the surface of the composite plates to compensate for their insufficient stiffness and strength. Ti and Mg have low mutual solid solubility and do not form intermetallic compounds, making direct composite of these two metals difficult; even if successfully composited, the interfacial bonding strength is also very low. Al and Mg have high solid solubility and can form solid solutions or intermetallic compounds under certain conditions; Al has high solid solubility in Ti, but Ti has low solid solubility in Al, and under certain conditions, they can form intermetallic compounds. Therefore, Al is selected as a binder to connect magnesium alloys and titanium alloys to achieve high-strength composites.

[0003] For composite plates that use Al as a binder to join magnesium alloys and titanium alloys, a cold-rolled composite plate method can be used. The surface of the composite plate is less prone to oxide layer formation, resulting in a higher quality bonding interface.

[0004] However, due to the low rolling temperature, the prepared composite plate is prone to large residual stress. At the same time, the rolling process requires large rolling pressure and rolling torque, resulting in high energy consumption. If the rolling force is large, it can also easily cause cracking at the edge of the composite plate (along the rolling direction), affecting the bonding of the composite plate interface and causing the loss of the component plate. Summary of the Invention

[0005] This invention provides a rolling process for Ti / Al / Mg / Al / Ti composite plates, including hot rolling, asynchronous cold rolling, and cross cold rolling, which can effectively overcome the shortcomings of existing technologies.

[0006] Therefore, the present invention proposes the following technical solution:

[0007] This invention discloses a rolling process for Ti / Al / Mg / Al / Ti composite plates, wherein the composite plates comprise: 6061 aluminum alloy, Ti-6Al-4V titanium alloy, and Mg-Zn-Zr magnesium alloy plates; Al is selected as a binder to connect the magnesium alloy and the titanium alloy; the rolling process includes: hot rolling and asynchronous cold rolling;

[0008] The asynchronous cold rolling includes: performing a single-pass asynchronous rolling with a reduction rate of 40% to 60% on a cold rolling mill, with a rolling force of 150 to 170 kN, asynchronously cold rolling to 2.8 to 8.6 mm, and an all-speed ratio of 1.1 to 1.3;

[0009] The hot rolling process includes: rolling a preheated Ti / Al / Mg / Al / Ti composite slab with a thickness of 15-25 mm and a width of 500-1000 mm in nine passes using a two-roll reversible hot rolling mill; wherein the upper and lower rolls are adjusted to 100-200°C, the total rolling reduction is 42.4-52.7%, the roll speed is 0.05-0.15 m / s, the hot rolling temperature is 400-500°C, and the slab is hot rolled to a thickness of 7.1-14.4 mm; no lubricant is used in the entire hot rolling process.

[0010] Furthermore, the asynchronous rolling is carried out on a reversible asynchronous cold rolling mill, with two work rolls of the same diameter. The asynchronous rolling conditions are achieved by the different speeds of the upper and lower work rolls. During the rolling process, the lower roll is a slow roll with a constant speed, while the upper roll is a fast roll with its speed adjusted according to the speed ratio.

[0011] Furthermore, the speed of the lower roller is 0.1 to 0.3 m / s, and the speed of the upper roller is 0.13 to 0.33 m / s.

[0012] Furthermore, the asynchronous rolling process includes cross-cold rolling; the cross-cold rolling process includes: first, rotating the composite plate 90° through a steel turning mill for cross rolling, with a reduction rate of 10% to 15% and a rolling force of 110 to 130 kN; then, feeding the plate along its length into the rolling mill for two passes of rolling, with a pass reduction rate of 10% to 15% and a rolling force of 110 to 130 kN, finally rolling to a thickness of 2 to 5.3 mm.

[0013] Furthermore, the rolling mill used for the cross-cold rolling is a four-roll cold rolling mill.

[0014] Furthermore, the nine-pass rolling process includes:

[0015] The first two passes have a reduction rate of 3-5%, a rolling force of 50-60 kN, and a rolling speed of 0.2-0.4 m / s;

[0016] The reduction rate for the third to fifth passes is 6-8%, the rolling force is 60-80 kN, and the rolling speed is 0.6-0.8 m / s.

[0017] The reduction rate of the sixth and seventh passes is 11-13%, the rolling force is 110-130kN, and the rolling speed is 0.3-0.5m / s;

[0018] The reduction rate of the eighth pass is 6-8%, the rolling force is 60-80kN, and the rolling speed is 0.6-0.8m / s;

[0019] The ninth pass controls the reduction rate to 1-3%, the rolling force to be 40-50 kN, and the rolling speed to be 1.0-1.2 m / s.

[0020] Furthermore, before the hot rolling and stacking, the process includes: preheating; the preheating includes: wrapping the multi-layer slab with aluminum foil, placing the wrapped Ti / Al / Mg / Al / Ti initial plate into a resistance furnace for preheating at a temperature of 350-450°C for a holding time of 10-30 minutes.

[0021] Furthermore, the process before preheating includes: surface pretreatment; the surface pretreatment includes: mechanical grinding and ultrasonic cleaning with acetone to remove surface oil; five thin sheets of magnesium alloy, aluminum alloy and titanium alloy of the same thickness are stacked and assembled in an alternating order of Ti+Al+Mg+Al+Ti to form a multi-layer slab blank with a thickness of 15-25mm.

[0022] Furthermore, the hot-rolled composite plate is further subjected to a thermal diffusion treatment. The thermal diffusion treatment includes placing the hot-rolled Ti / Al / Mg / Al / Ti composite plate in a resistance furnace, heating it to 300-350°C and holding it at that temperature for 24-30 hours to perform the thermal diffusion treatment of the composite plate.

[0023] Furthermore, the process after the thermal diffusion treatment also includes: surface treatment; the surface treatment includes: polishing the surface of the composite board.

[0024] The beneficial effects of this invention are:

[0025] This invention uses high-strength and high-rigidity titanium alloy on the surface of magnesium-aluminum composite plate to compensate for its lack of rigidity and strength, and improves the defects of magnesium alloy in terms of plasticity and corrosion resistance.

[0026] This invention employs an asynchronous cold rolling process. The speed difference between the upper and lower rolls subjects the material to a pair of shear stresses, causing internal crystal tilting, weakening the basal texture, accelerating dislocation movement, increasing the deformation per unit time, and storing more dislocations. This process coordinates the storage of geometrically necessary dislocations that are incompatible with plastic deformation, thereby improving the strength and toughness of the material.

[0027] This invention employs a cross-rolling process to control the amount and force of reduction at the edges of the sheet metal, thereby solving the problem of inconsistent thickness variations at the edges and in the middle of the rolled piece. It also straightens warped sheet metal, demonstrating good practical results and significant advancements. Attached Figure Description

[0028] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0029] Figure 1 A simplified flowchart of the rolling process for Ti / Al / Mg / Al / Ti composite plates;

[0030] Figure 2 The image shows the backscattering pattern at the interface of the Ti / Al / Mg / Al / Ti composite plate.

[0031] Figure 3 Optical microstructure of the central region of the Mg-Zn-Zr magnesium alloy substrate in Ti / Al / Mg / Al / Ti composite plates after different asynchronous rolling: (a) Example 1 with a rate ratio of 1.1; (b) Example 2 with a rate ratio of 1.2; (c) Example 3 with a rate ratio of 1.3;

[0032] Figure 4 The stress-strain curves are from the tensile test after rolling. Detailed Implementation

[0033] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0034] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0035] This invention provides a Ti / Al / Mg / Al / Ti composite plate, which comprises: 6061 aluminum alloy, Ti-6Al-4V titanium alloy and Mg-Zn-Zr magnesium alloy plate; Al is selected as a binder to connect the magnesium alloy and the titanium alloy.

[0036] The chemical composition of 6061 aluminum alloy by weight percentage is as follows: Si 0.4-0.8%, Fe 0.6-0.8%, Cu 0.15-0.40%, Mn 0.1-0.2%, Mg 0.9-1.1%, Cr 0.04-0.35%, Ti 0.1-0.2%, Zn 0.1-0.4%, C<0.01%, P<0.01%, S<0.01%, N<0.05%, O<0.05%, balance Al.

[0037] The chemical composition of Ti-6Al-4V titanium alloy by weight percentage is as follows: Al 5.0~7.0%, V 3.8~4.2%, Fe 0.15~0.25%, C<0.01%, Mn<0.01%, P<0.01%, S<0.01%, N<0.05%, O<0.08%, balance Ti.

[0038] The chemical composition of Mg-Zn-Zr magnesium alloy by weight percentage is as follows: Zn 5.5-6.5%, Zr 0.30-0.50%, C<0.01%, Mn<0.1%, Fe<0.03%, Si<0.01%, P<0.01%, S<0.01%, N<0.05%, O<0.08%, with the balance being Mg.

[0039] For the aforementioned Ti / Al / Mg / Al / Ti composite plate, this invention proposes a rolling process, such as... Figure 1 As shown, the process flow includes:

[0040] S1. Surface pretreatment;

[0041] The surface pretreatment includes: mechanical grinding and ultrasonic cleaning with acetone to remove surface oil; specifically, mechanical grinding involves sanding the surface of the heat-diffused composite board.

[0042] After surface treatments such as silicon carbide sandpaper polishing and acetone ultrasonic cleaning, five thin sheets of magnesium alloy, aluminum alloy and titanium alloy of the same thickness are stacked and assembled in an alternating order of Ti+Al+Mg+Al+Ti to form a multi-layer slab blank with a thickness of 15-25mm.

[0043] S2, Preheating;

[0044] The multi-layer slab is wrapped with aluminum foil to prevent misalignment during rolling, and then placed in an electric resistance furnace for uniform preheating. The wrapped Ti / Al / Mg / Al / Ti initial plate is then placed in the electric resistance furnace for preheating at 350–450℃ for 10–30 minutes. After preheating, the aluminum foil-wrapped plate is removed for rolling, and the rolling speed must be fast to prevent heat loss from affecting the interfacial bonding during rolling.

[0045] S3, hot-rolled stacked rolls;

[0046] The hot rolling process is as follows: a preheated Ti / Al / Mg / Al / Ti composite slab with a thickness of 15-25 mm and a width of 500-1000 mm is rolled in nine passes using a two-roll reversible hot rolling mill; the upper and lower rolls are adjusted to 100-200℃, the total rolling reduction is 42.4-52.7%, the roll speed is 0.05-0.15 m / s, the hot rolling temperature is 400-500℃, and the thickness is rolled to 7.1-14.4 mm. No lubricant is used in the entire hot rolling process.

[0047] The first two passes have a reduction rate of 3-5%, a rolling force of 50-60 kN, and a rolling speed of 0.2-0.4 m / s;

[0048] The reduction rate for the third to fifth passes is 6-8%, the rolling force is 60-80 kN, and the rolling speed is 0.6-0.8 m / s.

[0049] The reduction rate of the sixth and seventh passes is 11-13%, the rolling force is 110-130kN, and the rolling speed is 0.3-0.5m / s;

[0050] The reduction rate of the eighth pass is 6-8%, the rolling force is 60-80kN, and the rolling speed is 0.6-0.8m / s;

[0051] The ninth pass controls the reduction rate to 1-3%, the rolling force to be 40-50 kN, and the rolling speed to be 1.0-1.2 m / s.

[0052] In the hot rolling and stacking process of composite plates, aluminum foil is used to cover the plates before stacking to prevent misalignment during rolling and ensure the bonding quality of the magnesium-aluminum-titanium interface.

[0053] S4, thermal diffusion treatment;

[0054] The steps of the thermal diffusion treatment are as follows: place the hot-rolled Ti / Al / Mg / Al / Ti composite plate in a resistance furnace, heat it to 300-350℃ and keep it at that temperature for 24-30 hours to carry out the thermal diffusion treatment of the composite plate.

[0055] S5. Surface treatment;

[0056] The composite board is sanded.

[0057] S6, asynchronous cold rolling;

[0058] The asynchronous cold rolling process is as follows: After sanding the surface of the heat-diffusion treated composite plate, it is then subjected to single-pass asynchronous rolling with a reduction rate of 40% to 60% on a cold rolling mill. The rolling force is 150 to 170 kN, and the asynchronous cold rolling is carried out to 2.8 to 8.6 mm. The speed ratio is 1.1 to 1.3. The lower roll is a slow roll, and the roll speed is kept constant. The upper roll is a fast roll, and the upper roll speed is adjusted according to the speed ratio. The lower roll speed is 0.1 to 0.3 m / s, and the upper roll speed is 0.13 to 0.33 m / s.

[0059] Asynchronous rolling is carried out on a reversible asynchronous cold rolling mill. The two work rolls have the same diameter. The asynchronous rolling conditions are achieved by the different speeds of the upper and lower work rolls. During the rolling process, the lower roll is a slow roll with a constant speed, while the upper roll is a fast roll with its speed adjusted according to the speed ratio.

[0060] This invention proposes an asynchronous cold rolling process for rolling the aforementioned composite plate. This process increases shear deformation in the interface region by changing the linear velocity on both sides of the plate during rolling, thereby improving the interface stability during conventional cold rolling and enhancing the metallurgical bonding at the interface. The backscattering pattern at the interface of the Ti / Al / Mg / Al / Ti composite plate is shown below. Figure 2 As shown.

[0061] In another embodiment, considering that asynchronous cumulative rolling technology cannot effectively control the amount and force of reduction at the edge of the sheet, resulting in inconsistent thickness variation at the edge and in the middle, causing sheet warping, the present invention performs cross rolling after asynchronous rolling.

[0062] S7, cross-cold rolling.

[0063] The steps of cross-cold rolling are as follows: First, the composite plate is rotated 90° by a steel turning machine for cross rolling with a reduction rate of 10% to 15% and a rolling force of 110 to 130 kN. Then, the plate is fed into the rolling mill along the length direction for two passes of rolling with a reduction rate of 10% to 15% and a rolling force of 110 to 130 kN, finally rolled to 2 to 5.3 mm.

[0064] The rolling mill used for cross-cold rolling is a four-roll cold rolling mill.

[0065] In the above technical solution, the purpose of the cross-rolling step of the composite plate is to control the pressing force and amount at the edge of the multi-layer slab, to prevent the plate from warping and cracking after rolling, and to ensure the shape and quality of the finished product.

[0066] The hot rolling, asynchronous, and cross-cold rolling processes of the above-mentioned Ti / Al / Mg / Al / Ti composite plates are described below with specific examples. In the examples, rectangular standard tensile specimens were prepared according to GB / T228-2002 (Metallic Materials - Tensile Testing at Room Temperature), and tensile tests were conducted on a CMT5105-SANS microcomputer-controlled electronic universal testing machine.

[0067] Example 1

[0068] A hot-rolling, asynchronous, and cross-cold rolling process for Ti / Al / Mg / Al / Ti composite plates includes the following steps:

[0069] S11. Raw material preparation: Prepare Mg-Zn-Zr magnesium alloy plate, 6061 aluminum alloy plate and Ti-6Al-4V titanium alloy plate with an initial thickness of 5mm. All the above plates are in the annealed state.

[0070] S12. Surface Pretreatment: The selected aluminum alloy, titanium alloy, and magnesium alloy plates are polished with silicon carbide sandpaper, followed by acetone cleaning to remove surface oxides and inclusions. The plates are then stacked in an alternating order of Ti+Al+Mg+Al+Ti to produce a multi-layer slab with a thickness of 25mm.

[0071] S13. Preheating: After wrapping the multi-layer slab with aluminum foil, place it in an electric resistance furnace for uniform preheating. The heating temperature is 450℃ and the holding time is 30min.

[0072] S14. Hot Rolling and Stacking: After preheating, the rolls are quickly removed and rolled on a two-roll hot rolling mill. The upper and lower rolls are set to 200°C, the total reduction is 42.4%, the roll speed is 0.05 m / s, and the hot rolling temperature is 500°C. The first two passes have a reduction of 3%, a rolling force of 50 kN, and a rolling speed of 0.4 m / s; the third to fifth passes have a reduction of 6%, a rolling force of 60 kN, and a rolling speed of 0.8 m / s; the sixth and seventh passes have a reduction of 11%, a rolling force of 110 kN, and a rolling speed of 0.5 m / s; the eighth pass has a reduction of 6%, a rolling force of 60 kN, and a rolling speed of 0.8 m / s; and the ninth pass has a reduction of 1%, a rolling force of 40 kN, and a rolling speed of 1.2 m / s. It is hot rolled to 14.4mm in 9 passes, and no lubricant is used in the entire hot rolling process.

[0073] S15: Thermal diffusion treatment: The hot-rolled Ti / Al / Mg / Al / Ti composite plate is placed in a resistance furnace and heated to 350℃ and held for 24 hours to carry out the thermal diffusion treatment of the composite plate.

[0074] S16: Surface treatment: Polish the surface of the composite board.

[0075] S17: Asynchronous cold rolling: Single-pass asynchronous cold rolling is performed using a four-roll cold rolling mill with a reduction rate of 40%, a rolling force of 150kN, a speed ratio of 1.1, a lower roll speed of 0.3m / s, an upper roll speed of 0.33m / s, and asynchronous cold rolling to 8.6mm.

[0076] S18: Cross-cold rolling: Cross-cold rolling is performed on a four-roll cold rolling mill. The composite plate is rotated 90° by a steel turner for cross rolling with a reduction rate of 15% and a rolling force of 130kN. The plate is then fed into the rolling mill along its length for two passes of rolling with a reduction rate of 15% and a rolling force of 130kN, finally rolling to 5.3mm.

[0077] Example 2

[0078] A hot-rolling, asynchronous, and cross-cold rolling process for Ti / Al / Mg / Al / Ti composite plates includes the following steps:

[0079] S21: Raw material preparation. Prepare Mg-Zn-Zr magnesium alloy plate, 6061 aluminum alloy plate and Ti-6Al-4V titanium alloy plate with an initial thickness of 4mm. All the above plates are in the annealed state.

[0080] S22: Surface pretreatment: The selected aluminum alloy, titanium alloy, and magnesium alloy plates are polished with silicon carbide sandpaper, followed by acetone cleaning to remove surface oxides and inclusions. The plates are then stacked in an alternating order of Ti+Al+Mg+Al+Ti to form a multi-layer slab with a thickness of 20mm.

[0081] S23: Preheating: After wrapping the multi-layer slab with aluminum foil, place it in an electric resistance furnace for uniform preheating. The heating temperature is 400℃ and the holding time is 20min.

[0082] S24: Hot rolling: After preheating, quickly remove the rolls and roll them on a two-roll hot rolling mill. The upper and lower rolls are set to 150°C, the total rolling reduction is 47.5%, the roll speed is 0.1 m / s, and the hot rolling temperature is 450°C.

[0083] The first two hot rolling passes have a reduction rate of 4%, a rolling force of 55 kN, and a rolling speed of 0.3 m / s; the third to fifth passes have a reduction rate of 7%, a rolling force of 70 kN, and a rolling speed of 0.7 m / s; the sixth and seventh passes have a reduction rate of 12%, a rolling force of 120 kN, and a rolling speed of 0.4 m / s; the eighth pass has a reduction rate of 7%, a rolling force of 70 kN, and a rolling speed of 0.7 m / s; and the ninth pass has a reduction rate of 2%, a rolling force of 45 kN, and a rolling speed of 1.1 m / s. The material is hot rolled to 10.5 mm in nine passes, without the use of lubricant throughout the entire hot rolling process.

[0084] S25: Thermal diffusion treatment: The hot-rolled Ti / Al / Mg / Al / Ti composite plate is placed in a resistance furnace and heated to 330℃ and held for 27 hours to carry out the thermal diffusion treatment of the composite plate.

[0085] S26: Surface treatment: Polish the surface of the composite board.

[0086] S27: Asynchronous cold rolling: Single-pass asynchronous cold rolling is performed using a four-roll cold rolling mill with a reduction rate of 50%, a rolling force of 160kN, a speed ratio of 1.2, a lower roll speed of 0.2m / s, an upper roll speed of 0.24m / s, and asynchronous cold rolling to 5.3mm.

[0087] S28: Cross-cold rolling: Cross-cold rolling is performed on a four-roll cold rolling mill. The composite plate is rotated 90° by a steel turner for cross rolling with a reduction rate of 12% and a rolling force of 120kN. The plate is then fed into the rolling mill along the length direction for two passes of rolling with a pass reduction rate of 12% and a rolling force of 120kN, finally rolled to 3.6mm.

[0088] Example 3

[0089] A hot-rolling, asynchronous, and cross-cold rolling process for Ti / Al / Mg / Al / Ti composite plates includes the following steps:

[0090] S31: Raw material preparation, including Mg-Zn-Zr magnesium alloy plate, 6061 aluminum alloy plate and Ti-6Al-4V titanium alloy plate with an initial thickness of 3mm. All of the above plates are in the annealed state.

[0091] S32: The selected aluminum alloy, titanium alloy, and magnesium alloy plates are polished with silicon carbide sandpaper, followed by acetone cleaning to remove surface oxides and inclusions. The plates are then stacked in an alternating order of Ti+Al+Mg+Al+Ti to produce a multi-layer slab with a thickness of 15mm.

[0092] S33: After wrapping the multi-layer slab with aluminum foil, place it in an electric resistance furnace for uniform preheating at a temperature of 350℃ and a holding time of 10 minutes.

[0093] S34: After preheating, quickly remove the rolls and roll them on a two-roll hot rolling mill. Adjust the upper and lower rolls to 100°C. The total rolling reduction is 52.7%, the roll speed is 0.15 m / s, and the hot rolling temperature is 400°C. The first two passes have a reduction of 5%, a rolling force of 60 kN, and a rolling speed of 0.2 m / s. The third to fifth passes have a reduction of 8%, a rolling force of 80 kN, and a rolling speed of 0.6 m / s. The sixth and seventh passes have a reduction of 13%, a rolling force of 130 kN, and a rolling speed of 0.3 m / s. The eighth pass has a reduction of 8%, a rolling force of 80 kN, and a rolling speed of 0.6 m / s. The ninth pass has a reduction of 3%, a rolling force of 50 kN, and a rolling speed of 1.0 m / s. After nine passes, the thickness is reduced to 7.1 mm. No lubricant is used throughout the hot rolling process.

[0094] S35: The hot-rolled Ti / Al / Mg / Al / Ti composite plate is placed in a resistance furnace, heated to 300℃ and held for 30 hours to carry out the thermal diffusion treatment of the composite plate.

[0095] S36: Surface treatment: Polish the surface of the composite board.

[0096] S37: Single-pass asynchronous cold rolling is performed using a four-roll cold rolling mill with a reduction rate of 60%, a rolling force of 170kN, a speed ratio of 1.3, a lower roll speed of 0.1m / s, an upper roll speed of 0.13m / s, and asynchronous cold rolling to 2.8mm.

[0097] S38: Cross-cold rolling is performed on a four-roll cold rolling mill. The composite plate is rotated 90° by a steel turner for cross rolling with a reduction rate of 10% and a rolling force of 110kN. The plate is then fed into the rolling mill along its length for two passes of rolling with a reduction rate of 10% and a rolling force of 110kN, finally rolled to 2mm.

[0098] In the three embodiments described above, different asynchronous rolling processes were performed on plates with different initial thicknesses, such as... Figure 3 As shown, the optical microstructure of the central region of the Mg-Zn-Zr magnesium alloy substrate in Ti / Al / Mg / Al / Ti composite plates after different asynchronous rolling processes is illustrated: (a) Example 1 with a rate ratio of 1.1; (b) Example 2 with a rate ratio of 1.2; (c) Example 3 with a rate ratio of 1.3. The tensile stress-strain curves after rolling are shown in the figure. Figure 4 As shown, the Ti / Al / Mg / Al / Ti composite plate formed by the above rolling process has high toughness.

[0099] The sequence numbers of the above embodiments of the present invention are for descriptive purposes only and do not represent the superiority or inferiority of the embodiments.

[0100] In the above embodiments of the present invention, the descriptions of each embodiment have different focuses. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions of other embodiments.

[0101] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions 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 rolling process of a Ti / Al / Mg / Al / Ti composite sheet material, characterized in that, The composite plate comprises: 6061 aluminum alloy, Ti 6Al 4V titanium alloy and Mg-Zn-Zr magnesium alloy plate; Al is selected as the binder to connect the magnesium alloy and the titanium alloy; the rolling process comprises: hot rolling stacking, asynchronous cold rolling and cross cold rolling; The asynchronous cold rolling comprises: single-pass asynchronous rolling on a cold rolling mill with a reduction ratio of 40% to 60%, a rolling force of 150 to 170 kN, asynchronous cold rolling to 2.8 to 8.6 mm, and an asynchronous ratio of 1.1 to 1.3; The hot rolling comprises: nine-pass rolling treatment of the Ti / Al / Mg / Al / Ti composite plate blank with a thickness of 15 to 25 mm and a width of 500 to 1000 mm after preheating through a two-roller reversible hot rolling mill; wherein the upper and lower rollers are adjusted to 100 to 200 DEG C, the total rolling reduction is 42.4 to 52.7%, the roller rotating speed is 0.05 to 0.15 m / s, the hot rolling temperature is 400 to 500 DEG C, the hot rolling is to 7.1 to 14.4 mm, and no lubricant is used in the whole hot rolling process; the nine-pass rolling treatment comprises: a reduction ratio of 3 to 5% in the first two passes, a rolling force of 50 to 60 kN, and a rolling speed of 0.2 to 0.4 m / s; a reduction ratio of 6 to 8% in the third to fifth passes, a rolling force of 60 to 80 kN, and a rolling speed of 0.6 to 0.8 m / s; a reduction ratio of 11 to 13% in the sixth to seventh passes, a rolling force of 110 to 130 kN, and a rolling speed of 0.3 to 0.5 m / s; a reduction ratio of 6 to 8% in the eighth pass, a rolling force of 60 to 80 kN, and a rolling speed of 0.6 to 0.8 m / s; and a control reduction ratio of 1 to 3% in the ninth pass, a rolling force of 40 to 50 kN, and a rolling speed of 1.0 to 1.2 m / s. The cross cold rolling comprises: first, transversely rolling the composite plate by 90 DEG through a steel turning machine with a reduction ratio of 10% to 15% and a rolling force of 110 to 130 kN, and then inputting the rolled plate along the length direction into a rolling mill for two-pass rolling with a reduction ratio of 10% to 15% and a rolling force of 110 to 130 kN to finally roll to 2 to 5.3 mm.

2. The rolling process of Ti / Al / Mg / Al / Ti composite sheet according to claim 1, characterized in that, The asynchronous rolling is performed on a reversible asynchronous cold rolling mill, the two work rolls have the same diameter, and the asynchronous rolling condition is realized by different rotating speeds of the upper and lower work rolls, the lower roll is a slow roll, the roll speed is kept constant during rolling, and the upper roll is a fast roll, the roll speed of the upper roll is adjusted according to the asynchronous ratio.

3. The rolling process of Ti / Al / Mg / Al / Ti composite sheet according to claim 2, characterized in that, The roll speed of the lower roll is 0.1 to 0.3 m / s, and the roll speed of the upper roll is 0.13 to 0.33 m / s.

4. The rolling process of the Ti / Al / Mg / Al / Ti composite sheet according to claim 1, characterized in that, The rolling mill used in the cross cold rolling is a four-roller cold rolling mill.

5. The rolling process of the Ti / Al / Mg / Al / Ti composite sheet according to claim 1, characterized in that, The hot rolling further comprises: preheating before the hot rolling; the preheating comprises: wrapping the multilayer plate blank with aluminum foil, and preheating the wrapped Ti / Al / Mg / Al / Ti initial plate in a resistance furnace at a temperature of 350 to 450 DEG C for 10 to 30 min.

6. The rolling process of a Ti / Al / Mg / Al / Ti composite sheet according to claim 5, characterized in that, The preheating further comprises: surface pretreatment before the preheating; the surface pretreatment comprises: mechanical polishing and acetone ultrasonic cleaning to remove surface oil stains; five magnesium alloy, aluminum alloy and titanium alloy thin plates with the same thickness are sequentially stacked and assembled according to the order of Ti + Al + Mg + Al + Ti interval alternation to form a multilayer plate blank with a thickness of 15 to 25 mm.

7. The rolling process of Ti / Al / Mg / Al / Ti composite sheet according to claim 1, characterized in that, The hot rolling and the accumulative rolling further comprise a heat diffusion treatment; the heat diffusion treatment comprises: placing the hot-rolled Ti / Al / Mg / Al / Ti composite plate in a resistance furnace, heating to 300-350 DEG C and keeping for 24-30 hours to perform the heat diffusion treatment of the composite plate.

8. The rolling process of a Ti / Al / Mg / Al / Ti composite sheet according to claim 7, characterized in that, The heat diffusion treatment further comprises a surface treatment; the surface treatment comprises: polishing the surface of the composite plate.

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