Magnesium-based composite material ribbon as well as preparation method and application thereof

Abstract

The invention discloses a magnesium-based composite material ribbon as well as a preparation method and application thereof. The preparation method of the magnesium-based composite material thin strip comprises the following steps: adding a metal particle reinforced magnesium-based composite material blank into a vacuum melt-spinning furnace with a melt viscosity real-time monitoring function, and electrifying an induction heating coil in the vacuum melt-spinning furnace to melt the blank into a melt; and the heating power of the induction heating coil is adjusted to enable the viscosity of the melt to reach the casting target viscosity, the melt is sprayed to a copper roller in a vacuum melt-spinning furnace for cooling and casting, and the magnesium-based composite material thin strip is obtained. The preparation method of the magnesium-based composite material thin strip has the advantages of being simple in technological process, high in production efficiency, high in yield and the like, and the prepared magnesium-based composite material thin strip is uniform in metal particle distribution, free of defects such as pores / looseness / cracks, excellent in mechanical property and suitable for large-scale industrial production and application.

Description

Technical Field

[0001] The invention relates to the technical field of metal-based composite materials, and in particular to a magnesium-based composite material thin strip and a preparation method and application thereof. Background Art

[0002] Magnesium alloy is an important lightweight material with a series of advantages such as low density, excellent thermal conductivity, good damping performance and electromagnetic shielding performance. It has a very broad application prospect in many fields such as automobiles, home appliances, 3C products, etc. However, due to the lower strength and toughness of magnesium alloy compared with non-ferrous metal materials such as aluminum and titanium, the scale development and market application of magnesium alloy strips are still in the primary stage.

[0003] The production process of magnesium alloy strip mainly includes casting and rolling, ingot hot rolling, ingot extrusion, etc. Ingot hot rolling and ingot extrusion are suitable for producing medium and thick strips with a thickness of more than 4 mm, while thin strips are generally produced by casting and rolling (first using casting and rolling to supply the billet, and then cold rolling at room temperature). At present, in order to improve the strength and toughness of magnesium alloys, the commonly used method is to add heterogeneous metal particles such as Ti and Mn to the magnesium alloy matrix as a reinforcing phase. However, since magnesium belongs to a close-packed hexagonal crystal structure, has few slip systems, low plasticity, and is prone to oxidation at high temperatures, and has poor pressure processing deformation ability, after adding metal particles to the magnesium alloy matrix, as the strength of the composite material increases, it becomes more difficult to prepare thin strips using conventional rolling, extrusion and other pressure processing methods. During the pressure processing, the thin strip is prone to defects such as pores, looseness, and cracks, and the production efficiency and yield rate are low, which is difficult to meet actual production requirements.

[0004] Therefore, it is of great significance to develop a method for preparing magnesium-based composite material thin strips with simple process flow, high production efficiency and high yield, and to prepare magnesium-based composite material thin strips with uniform metal particle distribution, no defects such as pores / looseness / cracks, and excellent mechanical properties. Summary of the invention

[0005] The purpose of the present invention is to provide a magnesium-based composite material thin strip and a preparation method and application thereof.

[0006] The technical solution adopted by the present invention is:

[0007] A method for preparing a magnesium-based composite material thin strip comprises the following steps:

[0008] The metal particle reinforced magnesium-based composite material blank is added into a vacuum belt spinning furnace with a real-time monitoring function of melt viscosity, and then the induction heating coil inside the vacuum belt spinning furnace is energized to melt the blank into a melt, and then the heating power of the induction heating coil is adjusted to make the viscosity of the melt reach the casting target viscosity, and then the melt is sprayed onto the copper roller inside the vacuum belt spinning furnace for cooling and casting, so as to obtain a magnesium-based composite material thin strip.

[0009] Preferably, the vacuum strip spinning furnace with real-time monitoring function of melt viscosity comprises a base and a furnace body installed on the base; the interior of the furnace body is provided with a high-temperature viscometer, a crucible, a spray hole blocking plate and a copper roller in sequence from top to bottom; the lower part of the high-temperature viscometer extends into the crucible and is in direct contact with the melt contained in the crucible; an induction heating coil is provided on the periphery of the crucible; a spray hole is provided at the bottom of the crucible; the spray hole blocking plate can be moved horizontally to open and close the spray hole at the bottom of the crucible; a furnace cover and a strip collecting tube are also provided on the outside of the furnace body away from the spray hole blocking plate.

[0010] Preferably, the viscosity measurement range of the high temperature viscometer is 0 to 10 Pa·s.

[0011] Preferably, the high temperature viscometer can move up and down.

[0012] Preferably, the crucible is made of graphite or quartz.

[0013] Preferably, the rotation speed of the copper roller is adjustable.

[0014] Preferably, the vacuum belt spinning furnace with real-time melt viscosity monitoring function also includes a vacuum pumping system.

[0015] Preferably, the vacuum belt-spinning furnace with real-time melt viscosity monitoring function also includes a water cooling system.

[0016] Preferably, the volume fraction of the metal particles in the metal particle reinforced magnesium-based composite material blank is 0.5% to 10%.

[0017] Preferably, the metal particles in the metal particle-reinforced magnesium-based composite material blank are at least one of Ti particles, TC4 particles, Mn particles, titanium metal compound particles, and manganese metal compound particles.

[0018] Preferably, the particle size of the metal particles in the metal particle reinforced magnesium-based composite material blank is 10 μm to 30 μm.

[0019] Preferably, the melting operation of the billet is carried out in an inert atmosphere.

[0020] Preferably, the inert atmosphere is at least one of argon, nitrogen, and a CO2 / SF6 mixed gas.

[0021] Preferably, the operating frequency of the induction heating coil is 50 Hz to 200 Hz. If the operating frequency of the induction heating coil is higher than 200 Hz, the electromagnetic stirring force is weak and the metal particles will settle in the crucible; if the operating frequency of the induction heating coil is lower than 50 Hz, the heating efficiency is low, the melting time of the blank is long, and the volatilization amount of magnesium element is large.

[0022] Preferably, the casting target viscosity is 0.5Pa·s to 3Pa·s. If the viscosity of the melt is lower than 0.5Pa·s, the metal particles will settle in the crucible, and the strip is prone to uneven distribution of metal particles; if the viscosity of the melt is higher than 3Pa·s, the melt has poor fluidity, the edge is poorly formed, and the strip is prone to defects such as pores and looseness.

[0023] Preferably, the cooling casting is performed at a copper roller speed of 20 m / s to 40 m / s and a melt cooling rate of 5×10 3 ℃ / s~10×10 3 ℃ / s. If the copper roller rotates too fast and / or the melt cools too fast, the strip will be too thin and prone to defects such as looseness; if the copper roller rotates too slow and / or the melt cools too slowly, the strip will be too thick and the matrix structure will coarsen, affecting the mechanical properties of the strip. The cooling rate of the melt is adjusted by adjusting the pressure and flow of the cooling water in the water cooling system.

[0024] Preferably, the cooling and casting operation of the melt is performed in an inert atmosphere.

[0025] Preferably, the inert atmosphere is at least one of argon, nitrogen, and a CO2 / SF6 mixed gas.

[0026] Preferably, the pressure of the inert atmosphere is ≤0.05 MPa.

[0027] A magnesium-based composite material thin strip is made by the above-mentioned preparation method.

[0028] Preferably, the magnesium-based composite material thin strip has a thickness of 0.5 mm to 2 mm.

[0029] Application of the magnesium-based composite material thin strip as described above in the aerospace field, automobile industry field, electronic product field, rail transportation field or medical device field.

[0030] The beneficial effects of the present invention are as follows: the method for preparing a magnesium-based composite material thin strip of the present invention has the advantages of simple process flow, high production efficiency, high yield rate, etc. The prepared magnesium-based composite material thin strip has uniform metal particle distribution, no defects such as pores / looseness / cracks, and excellent mechanical properties, and is suitable for large-scale industrial production and application.

[0031] Specifically:

[0032] 1) The present invention uses the melt viscosity as a judgment basis to adjust the heating power of the induction heating coil, the cooling rate of the melt, the rotation speed of the copper rod and other process parameters, thereby achieving the effect of adjusting the cooling rate and thickness of the magnesium-based composite material thin strip, with a simple process flow, high production efficiency and high yield;

[0033] 2) The present invention can produce magnesium-based composite material thin strips with good interface bonding and metal particles reinforcement in a short process and in a stable manner. The magnesium-based composite material thin strips have uniform metal particle distribution, no defects such as pores / looseness / cracks, and excellent mechanical properties, and are suitable for large-scale industrial production and application. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 It is a schematic structural diagram of a vacuum belt spinning furnace with a real-time melt viscosity monitoring function in the present invention.

[0035] Description of the symbols in the accompanying drawings: 10, base; 20, furnace body; 30, high temperature viscometer; 40, crucible; 50, injection hole blocking plate; 60, copper roller; 70, induction heating coil; 80, furnace cover; 90, strip collecting cylinder; 100, strip.

[0036] Figure 2 This is a physical picture of the magnesium-based composite material thin strip prepared in Example 1.

[0037] Figure 3 This is a metallographic microscope image of the magnesium-based composite material thin strip prepared in Example 1.

[0038] Figure 4 This is a metallographic microscope image of the magnesium-based composite material thin strip prepared in Example 2.

[0039] Figure 5 This is a physical picture of the magnesium-based composite material thin strip prepared in Comparative Example 1.

[0040] Figure 6 This is a metallographic microscope image of the magnesium-based composite material strip prepared in Comparative Example 1. DETAILED DESCRIPTION

[0041] The present invention will be further explained and illustrated below in conjunction with specific embodiments.

[0042] The vacuum belt-spinning furnace with real-time monitoring function of melt viscosity in Examples 1 to 10 and Comparative Examples 1 to 8 (schematic diagram as shown in FIG. Figure 1As shown; compared with the commercially available vacuum strip spinning furnace, the main difference is that it also includes a high-temperature viscometer, while the other structures have no obvious differences) consists of a base 10, a furnace body 20, a high-temperature viscometer 30, a crucible 40, a spray hole blocking plate 50, a copper roller 60, an induction heating coil 70, a furnace cover 80, a strip collecting cylinder 90, a vacuum system and a water cooling system; the furnace body 20 is installed on the base 10; the high-temperature viscometer 30, the crucible 40, the spray hole blocking plate 50 and the copper roller 60 are arranged in sequence from top to bottom inside the furnace body 20; the lower part of the high-temperature viscometer 30 extends into the crucible 40 and is in direct contact with the melt formed by the melting of the material inside the crucible 40; the high-temperature viscosity The viscometer 30 can move up and down; the viscosity measuring range of the high temperature viscometer 30 is 0 to 10 Pa·s; the induction heating coil 70 is arranged on the periphery of the crucible 40; the bottom of the crucible 40 is provided with a spray hole; the material of the crucible 40 is graphite or quartz; the spray hole blocking plate 50 can move horizontally and is used to open and close the spray hole at the bottom of the crucible 40; the rotation speed of the copper roller 60 is adjustable; the furnace cover 80 and the strip collecting cylinder 90 are arranged on the side of the outside of the furnace body 20 away from the spray hole blocking plate 50; the strip collecting cylinder 90 is used to collect the strip 100; the vacuum system (not shown) is used to evacuate the inside of the furnace body 20 to a vacuum; the water cooling system (not shown) is used to cool the copper roller 60.

[0043] Embodiment 1:

[0044] A magnesium-based composite material thin strip, the preparation method of which is as follows:

[0045] A titanium particle-reinforced AZ91D magnesium alloy composite material blank (the average particle size of the titanium particles is 20 μm, and the volume fraction in the blank is 5%) is added to a crucible (made of quartz) of a vacuum belt-spinning furnace with a real-time melt viscosity monitoring function, and the injection hole blocking plate is moved to close the injection hole at the bottom of the crucible. After closing the furnace cover, the furnace is evacuated to a vacuum degree of 5 Pa using a vacuum pumping system, and high-purity argon gas is introduced into the furnace. When the pressure in the furnace is balanced with the external atmospheric pressure, the pressure reducing valve is opened while argon gas is introduced into the furnace. On the one hand, exhaust gas is discharged to the outside of the furnace through the pressure reducing valve to keep the furnace in a slightly positive pressure state of ≤0.05MPa. Then, the induction heating coil is energized to melt the blank into a melt. The working frequency of the induction heating coil is 100Hz. Then, the heating power of the induction heating coil is adjusted to stabilize the viscosity of the melt at 1.5Pa·s. Then, the injection hole blocking plate is moved to open the injection hole at the bottom of the crucible, so that the melt is sprayed onto the copper roller for cooling and casting. The rotation speed of the copper roller is controlled to be 30m / s and the cooling speed of the melt is controlled to be 7.6×10 3 ℃ / s, and the strip is collected by a strip collecting tube to obtain a magnesium-based composite material thin strip (thickness of 1.25 mm).

[0046] Note:

[0047] The preparation process of the titanium particle reinforced AZ91D magnesium alloy composite material billet is as follows: the titanium particles and the AZ91D magnesium alloy particles are mixed evenly, and then pressed into a round rod-shaped prefabricated block, and then placed in a vacuum sintering furnace for sintering under a vacuum environment to obtain a titanium particle reinforced AZ91D magnesium alloy composite material billet (ingot).

[0048] The actual picture of the magnesium-based composite material strip prepared in this embodiment is as follows: Figure 2 As shown in the metallographic microscope picture (magnified 200 times) Figure 3 shown.

[0049] Depend on Figure 2 It can be seen that the edge of the magnesium-based composite material thin strip is completely formed, and no obvious defects such as pores, looseness, and cracks are observed.

[0050] Depend on Figure 3 It can be seen that the titanium particles are evenly distributed in the magnesium alloy matrix, the interface bonding is good, there is no agglomeration phenomenon, and there are no defects such as pores and looseness.

[0051] Embodiment 2:

[0052] A magnesium-based composite material thin strip, the preparation method of which is as follows:

[0053] The VW94 magnesium alloy composite material reinforced with titanium particles (the average particle size of the titanium particles is 15 μm, and the volume fraction in the billet is 2%) is added into the crucible (made of high-purity graphite) of a vacuum belt-spinning furnace with a real-time monitoring function for melt viscosity, and the injection hole blocking plate is moved to close the injection hole at the bottom of the crucible. After closing the furnace cover, the vacuum system is used to evacuate the furnace to a vacuum degree of 7 Pa, and then a CO2 / SF6 mixed gas is introduced into the furnace. When the pressure in the furnace is balanced with the external atmospheric pressure, the pressure reducing valve is opened while CO2 is introduced into the furnace. 2 / SF6 mixed gas, while exhausting it to the outside of the furnace through the pressure reducing valve, so that the furnace always maintains a micro-positive pressure state of ≤0.03MPa, and then the induction heating coil is energized to melt the billet into a melt. The working frequency of the induction heating coil is 50Hz, and then the heating power of the induction heating coil is adjusted to stabilize the viscosity of the melt at 1Pa·s, and then the injection hole blocking plate is moved to open the injection hole at the bottom of the crucible, so that the melt is sprayed onto the copper roller for cooling and casting. The rotation speed of the copper roller is controlled to be 20m / s and the cooling speed of the melt is controlled to be 6.8×10 3 ℃ / s, and the strip is collected by a strip collecting tube to obtain a magnesium-based composite material thin strip (thickness of 1.80 mm).

[0054] Note:

[0055] The preparation process of the titanium particle reinforced VW94 magnesium alloy composite material billet is as follows: the titanium particles and the VW94 magnesium alloy particles are mixed evenly, and then pressed into a round rod-shaped prefabricated block, and then placed in a vacuum sintering furnace for sintering under a vacuum environment to obtain a titanium particle reinforced VW94 magnesium alloy composite material billet (ingot).

[0056] The metallographic microscope image (magnified 200 times) of the magnesium-based composite material strip prepared in this embodiment is as follows: Figure 4 shown.

[0057] Depend on Figure 4 It can be seen that the titanium particles are evenly distributed in the magnesium alloy matrix, the interface bonding is good, there is no agglomeration phenomenon, and there are no defects such as pores and looseness.

[0058] Embodiment 3:

[0059] A magnesium-based composite material thin strip is identical to Example 1 except that the viscosity of the melt is adjusted from "1.5 Pa·s" to "2.8 Pa·s" during preparation.

[0060] Embodiment 4:

[0061] A magnesium-based composite material thin strip is identical to Example 1 except that the viscosity of the melt is adjusted from "1.5 Pa·s" to "0.7 Pa·s" during preparation.

[0062] Embodiment 5:

[0063] A magnesium-based composite material thin strip is prepared in the same manner as in Example 1 except that the rotation speed of the copper roller is adjusted from "30 m / s" to "38 m / s" during preparation.

[0064] Embodiment 6:

[0065] A magnesium-based composite material thin strip is prepared in the same manner as in Example 1 except that the rotation speed of the copper roller is adjusted from "30 m / s" to "22 m / s" during preparation.

[0066] Embodiment 7:

[0067] A magnesium-based composite material thin strip, in addition to cooling the melt from "7.6×10 3 ℃ / s" is adjusted to "9.8×10 3 Except for "℃ / s", the rest is exactly the same as Example 1.

[0068] Embodiment 8:

[0069] A magnesium-based composite material thin strip, in addition to cooling the melt from "7.6×10 3 ℃ / s" is adjusted to "5.3×10 3Except for "℃ / s", the rest is exactly the same as Example 1.

[0070] Embodiment 9:

[0071] A magnesium-based composite material thin strip is exactly the same as Example 1 except that the operating frequency of the induction heating coil is adjusted from "100 Hz" to "200 Hz" during preparation.

[0072] Embodiment 10:

[0073] A magnesium-based composite material thin strip is exactly the same as Example 1 except that the operating frequency of the induction heating coil is adjusted from "100 Hz" to "50 Hz" during preparation.

[0074] Comparative Example 1:

[0075] A magnesium-based composite material thin strip is identical to Example 1 except that the viscosity of the melt is adjusted from "1.5 Pa·s" to "3.5 Pa·s" during preparation.

[0076] The actual picture of the magnesium-based composite material strip prepared in this comparative example is as follows Figure 5 As shown in the metallographic microscope picture (magnified 500 times) Figure 6 shown.

[0077] Depend on Figure 5 It can be seen that the edge part of the magnesium-based composite material thin strip is not fully formed and has obvious defects such as pores and looseness.

[0078] Depend on Figure 6 It can be seen that the magnesium-based composite material strips have obvious looseness and particle agglomeration defects.

[0079] Comparative Example 2:

[0080] A magnesium-based composite material thin strip is identical to Example 1 except that the viscosity of the melt is adjusted from "1.5 Pa·s" to "0.3 Pa·s" during preparation.

[0081] Comparative Example 3:

[0082] A magnesium-based composite material thin strip is prepared in the same manner as in Example 1 except that the rotation speed of the copper roller is adjusted from "30 m / s" to "15 m / s" during preparation.

[0083] Comparative Example 4:

[0084] A magnesium-based composite material thin strip is prepared in the same manner as in Example 1 except that the rotation speed of the copper roller is adjusted from "30 m / s" to "45 m / s" during preparation.

[0085] Comparative Example 5:

[0086] A magnesium-based composite material thin strip, in addition to cooling the melt from "7.6×10 3 ℃ / s" is adjusted to "3.8×10 3 Except for "℃ / s", the rest is exactly the same as Example 1.

[0087] Comparative Example 6:

[0088] A magnesium-based composite material thin strip, in addition to cooling the melt from "7.6×10 3 ℃ / s" is adjusted to "13.0×10 3 Except for "℃ / s", the rest is exactly the same as Example 1.

[0089] Comparative Example 7:

[0090] A magnesium-based composite material thin strip is exactly the same as Example 1 except that the operating frequency of the induction heating coil is adjusted from "100 Hz" to "500 Hz" during preparation.

[0091] Comparative Example 8:

[0092] A magnesium-based composite material thin strip is exactly the same as Example 1 except that the operating frequency of the induction heating coil is adjusted from "100 Hz" to "10 Hz" during preparation.

[0093] Performance Test:

[0094] 1) The test results of the molding quality (thickness, appearance quality, particle distribution uniformity and casting defects) of the magnesium-based composite material thin strips in Examples 1 to 10 and Comparative Examples 1 to 8 are shown in the following table:

[0095] Table 1 Forming quality test results of magnesium-based composite strips

[0096]

[0097]

[0098]

[0099] It can be seen from Table 1 that the viscosity of the melt, the rotation speed of the copper roller, the cooling rate of the melt, the working frequency of the induction heating coil, etc. have an important influence on the forming and quality of the thin strip. The selection of reasonable process parameters can prepare a magnesium-based composite material thin strip with good forming, no macroscopic defects and uniform distribution of reinforcing particles.

[0100] 2) The mechanical properties test results of the magnesium-based composite material strips in Examples 1 to 10 and Comparative Examples 1 to 8 are shown in the following table:

[0101] Table 2 Mechanical properties test results of magnesium matrix composite strips

[0102] Test items Tensile strength(MPa) Yield strength(MPa) Elongation(%) Example 1 342 233 15.4 Example 2 480 312 10.6 Example 3 321 218 13.6 Example 4 335 228 15.1 Example 5 328 220 13.8 Example 6 330 225 14.2 Example 7 319 216 13.1 Example 8 316 219 13.5 Example 9 336 224 15.1 Example 10 332 221 14.9 Comparative Example 1 256 187 7.8 Comparative Example 2 287 198 9.1 Comparative Example 3 291 202 9.7 Comparative Example 4 298 210 7.2 Comparative Example 5 252 186 7.6 Comparative Example 6 266 193 7.9 Comparative Example 7 279 188 8.8 Comparative Example 8 264 176 9.3

[0103] Note:

[0104] Tensile strength: Tested in accordance with "GB / T 16865-2013 Specimens and methods for tensile testing of deformed aluminum, magnesium and their alloy products";

[0105] Yield strength: Tested in accordance with "GB / T 16865-2013 Specimens and methods for tensile testing of deformed aluminum, magnesium and their alloy products";

[0106] Elongation (elongation after fracture): Tested in accordance with "GB / T 16865-2013 Specimens and methods for tensile testing of deformed aluminum, magnesium and their alloy products".

[0107] It can be seen from Table 2 that the magnesium-based composite material thin strip prepared by the process of the present invention has excellent room temperature mechanical properties and elongation.

[0108] The above embodiments are preferred implementation modes of the present invention, but the implementation modes of the present invention are not limited to the above embodiments. Any other changes, modifications, substitutions, combinations, and simplifications that do not deviate from the spirit and principles of the present invention should be equivalent replacement methods and are included in the protection scope of the present invention.

Claims

1. A method for preparing a magnesium-based composite material thin strip, characterized in that: The following steps are involved: The metal particle reinforced magnesium-based composite material blank is added into a vacuum belt spinning furnace with a real-time monitoring function of melt viscosity, and then the induction heating coil inside the vacuum belt spinning furnace is energized to melt the blank into a melt, and then the heating power of the induction heating coil is adjusted to make the viscosity of the melt reach the casting target viscosity, and then the melt is sprayed onto the copper roller inside the vacuum belt spinning furnace for cooling and casting, so as to obtain a magnesium-based composite material thin strip.

2. The method for preparing the magnesium-based composite material strip according to claim 1, characterized in that: The vacuum strip spinning furnace with real-time melt viscosity monitoring function comprises a base and a furnace body installed on the base; the interior of the furnace body is provided with a high-temperature viscometer, a crucible, a spray hole blocking plate and a copper roller in sequence from top to bottom; the lower part of the high-temperature viscometer extends into the crucible and is in direct contact with the melt contained in the crucible; an induction heating coil is provided on the periphery of the crucible; a spray hole is provided at the bottom of the crucible; the spray hole blocking plate can be moved horizontally to open and close the spray hole at the bottom of the crucible; a furnace cover and a strip collecting tube are also provided on the side of the exterior of the furnace body away from the spray hole blocking plate.

3. The method for preparing the magnesium-based composite material strip according to claim 1 or 2, characterized in that: The volume fraction of the metal particles in the metal particle reinforced magnesium-based composite material blank is 0.5% to 10%.

4. The method for preparing a magnesium-based composite material strip according to claim 1 or 2, characterized in that: The metal particles in the metal particle reinforced magnesium-based composite material blank are at least one of Ti particles, TC4 particles, Mn particles, titanium metal compound particles, and manganese metal compound particles; the particle size of the metal particles in the metal particle reinforced magnesium-based composite material blank is 10μm to 30μm.

5. The method for preparing the magnesium-based composite material strip according to claim 1 or 2, characterized in that: The operating frequency of the induction heating coil is 50 Hz to 200 Hz.

6. The method for preparing a magnesium-based composite material strip according to claim 1 or 2, characterized in that: The casting target viscosity is 0.5 Pa·s to 3 Pa·s.

7. The method for preparing a magnesium-based composite material strip according to claim 1 or 2, characterized in that: The cooling casting is carried out at a speed of 20 m / s to 40 m / s for the copper roller and a cooling speed of 5×10 3 ℃ / s~10×10 3 ℃ / s.

8. A magnesium-based composite material thin strip, characterized in that: Prepared by the preparation method according to any one of claims 1 to 7.

9. The magnesium-based composite material strip according to claim 8, characterized in that: The thickness of the magnesium-based composite material thin strip is 0.5 mm to 2 mm.

10. Use of the magnesium-based composite material strip as claimed in claim 8 or 9 in the fields of aerospace, automobile industry, electronic products, rail transportation or medical equipment.

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