A Mg-Al-Ta composite material with good interfacial bonding and its preparation method

Abstract

This invention discloses a Mg-Al-Ta composite plate with good interfacial bonding and its preparation method, comprising the following steps: S1, raw material preparation, including a pure tantalum plate, an AZ-based magnesium alloy plate with bimodal separation non-basal surface texture, and an aluminum plate; S2, stacking and fixing the raw materials in the order of magnesium alloy plate, aluminum plate, and pure tantalum plate to obtain a rolled billet; S3, rolling and deforming the rolled billet to obtain a deformed plate; S4, immersing the deformed plate in liquid nitrogen for cryogenic treatment, and then performing low-temperature recovery annealing to obtain a heat-treated plate; S5, rolling and deforming the heat-treated plate to obtain a secondary deformed plate; S6, performing high-temperature diffusion annealing on the secondary deformed plate to obtain a Mg-Al-Ta composite plate with good interfacial bonding. This method can improve the interfacial bonding strength of the Mg-Al-Ta composite plate, laying the foundation for the engineering application of this type of composite plate.

Description

Technical Field

[0001] This invention relates to the preparation of dissimilar metal composite plates, specifically to Mg-Al-Ta composite plates with good interfacial bonding and their preparation methods. Background Technology

[0002] Deep space exploration presents humanity with greater challenges, primarily due to the powerful magnetic fields on its surface and the high density of high-energy particles in its orbits. The resulting intense radiation environment places extremely stringent demands on the radiation resistance of spacecraft. Currently, existing radiation-resistant material systems mainly fall into categories such as bulk metal matrix composites, coating materials, and layered composite materials, including tungsten-infiltrated aluminum matrix composites, radiation-resistant coatings, and pure niobium or pure tantalum plates. However, these systems share common problems such as high weight, low shielding effectiveness, and poor tolerance to prolonged space environments, failing to meet the urgent need for lightweight radiation-resistant materials in deep space probe shielding structures.

[0003] The simulation study of the transport process of high-energy particles in multilayer materials, titled “Optimization Design of Radiation Vault in Jupiter Orbiting Mission” (JZ Wang, JN Ma, JW Qiu, D. Tian, ​​AW Zhu, QX Zhang, AS Zhou. IEEE Transactions on Nuclear Science, (66) 2019, 2179-2187.), found that the Mg / Ta composite plate had the highest equivalent shielding efficiency while achieving the same radiation shielding effect in Jupiter orbit. Compared with radiation shielding materials using Ta heavy metal elemental materials, the Mg / Ta composite plate can save about 45% of the weight while achieving the same shielding effect. However, due to the significant differences between Mg and Ta in terms of melting point (Ta's melting point is about 2995℃, and Mg's melting point is about 650℃), crystal structure (Ta has a body-centered cubic lattice, and Mg has a close-packed hexagonal lattice), and atomic radius (Ta's atomic radius is significantly larger than Mg's), there are currently few reports on the processing and preparation of Mg / Ta composite plates.

[0004] Chinese patent publication CN113733685A discloses a lightweight, high-strength Mg-Al-Ta composite metal sheet and its rolling forming method. While this method can achieve the processing and preparation of Mg / Ta composite sheets, its process involves separately heat-treating the Mg and Ta sheets at different temperatures before stacking and fixing them. The temperature change of the stacked sheets before rolling deformation is difficult to control effectively, resulting in low production efficiency. Chinese patent publication CN113352708A discloses a lightweight, high-strength Mg-Al-Ta composite metal sheet and its room-temperature rolling forming method. Although this method avoids the oxidation and energy consumption problems that may be introduced by medium- and high-temperature rolling, in order to effectively reduce the residual stress between different metal sheets and ensure smooth rolling deformation, low-temperature recovery annealing and high-temperature diffusion annealing need to be introduced between rolling passes, and multiple rolling deformation passes are required, resulting in low production efficiency. Chinese patent publication number CN112742870A reports a method for preparing a shielded magnesium-tantalum multilayer composite plate. Although it can realize the processing and preparation of Mg / Ta composite plates, its process involves high-temperature rolling in a vacuum to avoid oxidation of the plate. This places high demands on the rolling equipment and rolling environment, and the production efficiency is not high.

[0005] On the one hand, the magnesium alloy sheets used in the aforementioned patents are mostly traditional high-temperature hot-rolled base-textured magnesium alloy sheets, whose plastic deformation capacity and rollability are significantly inferior to bimodal non-base-textured magnesium alloy sheets. (See "Improved stretch formability of AZ31 sheet via texture control by introducing a continuous bending channel into equal channel angular rolling[J]" (DH Song, T. Zhou, J. Tu, LX Shi, B. Song, L. Hu, MB Yang, Q. Chen, LW Lu. Journal of Materials Processing Technology, 2018, 259: 380-386.). On the other hand, the aforementioned patents often employ low-temperature annealing to release residual stress within the deformed sheet, thereby ensuring the smooth progress of subsequent rolling deformation. “Investigation on microstructure and mechanical properties of hot-rolled AZ31 Mg alloy with various cryogenic treatments[J]” (B. Che, LW Lu, JL Zhang, J. Teng, L. Chen, Y. Xu, T. Wang, L. Huang, ZQ Wu. Journal of Materials Research and Technology, (19) 2022: 4457-4570.) shows that deep cryogenic liquid nitrogen treatment of deformed magnesium alloy plates can effectively release residual stress in the deformed plates. Summary of the Invention

[0006] The purpose of this invention is to provide a Mg-Al-Ta composite material with good interfacial bonding and its preparation method, which can improve the interfacial bonding force of the Mg-Al-Ta composite material and lay the foundation for the engineering application of this type of composite material.

[0007] The method for preparing the Mg-Al-Ta composite material with good interfacial bonding according to the present invention includes the following steps:

[0008] S1, Raw material preparation, including pure tantalum plate, AZ-series magnesium alloy plate with bimodal separation non-basal surface texture, and aluminum plate;

[0009] S2, the raw materials are stacked and fixed in the order of magnesium alloy plate, aluminum plate and pure tantalum plate to obtain the rolled billet;

[0010] S3, the rolled billet is rolled and deformed to obtain a deformed sheet;

[0011] S4, the deformed sheet is first immersed in liquid nitrogen for cryogenic treatment, and then subjected to low-temperature recovery annealing to obtain a heat-treated sheet;

[0012] S5, the heat-treated sheet is rolled and deformed to obtain a secondary deformed sheet;

[0013] S6. The secondary deformed plate is subjected to high-temperature diffusion annealing to obtain a Mg-Al-Ta composite plate with good interfacial bonding.

[0014] Furthermore, the specific process parameters for rolling deformation in S3 are as follows: rolling temperature is 100~150℃, thinning rate per rolling pass is 40~60%, roll temperature on the side closer to the AZ-based magnesium alloy plate is 100~160℃, and roll temperature on the side closer to the pure tantalum plate is 180~250℃.

[0015] Furthermore, the cryogenic treatment time in S4 is 60~360min.

[0016] Furthermore, the annealing temperature for the low-temperature recovery annealing treatment in S4 is 100~180℃, the annealing time is 30~75min, and the cooling method is furnace cooling or external furnace cooling.

[0017] Furthermore, the specific process parameters for rolling deformation in S5 are as follows: rolling temperature is 150~200℃, thinning rate per rolling pass is 40~60%, roll temperature on the side closer to the AZ-based magnesium alloy plate is 150~200℃, and roll temperature on the side closer to the pure tantalum plate is 220~300℃.

[0018] Furthermore, the uniform pressure of the high-temperature diffusion annealing treatment in S6 is 0.03~0.10MPa, the diffusion annealing temperature is 400~480℃, and the diffusion annealing time is 1.0~4.5h.

[0019] Furthermore, the aluminum plate is a pure aluminum plate or an aluminum alloy plate.

[0020] A Mg-Al-Ta composite material with good interfacial bonding is prepared by the method for preparing Mg-Al-Ta composite materials with good interfacial bonding described in this invention.

[0021] The beneficial effects of this invention are:

[0022] 1. This invention stacks and fixes AZ-based magnesium alloy plates with a bimodal non-basal texture and pure tantalum plates in a predetermined order using an intermediate aluminum plate. The arrangement of the aluminum plates helps to improve the atomic diffusion rate during high-temperature diffusion annealing. Low-temperature rolling achieves large deformation of the plate while minimizing oxidation. Subsequent cryogenic liquid nitrogen treatment and low-temperature recovery annealing effectively release residual stress within the deformed plate and plastic instabilities (shear bands, vacancies, cracks, etc.) at the interface. Finally, a second low-temperature rolling process further accumulates plastic strain, combined with subsequent high-temperature diffusion annealing, ultimately achieving a harmonious coexistence of mechanical and metallurgical bonding at the Mg / Ta composite plate interface, resulting in a well-bonded Mg-Al-Ta composite plate. This invention provides a feasible process route and theoretical guidance for the forming and preparation of Mg / Ta composite plates, laying the foundation for the engineering application of this type of composite plate.

[0023] 2. This invention uses AZ-series magnesium alloy sheets with bimodal separation non-base surface texture to replace traditional base surface textured sheets. These sheets are stacked and fixed with intermediate aluminum sheets and pure tantalum sheets in a set order. Under low temperature conditions of 100~150℃, single-pass large deformation (40%~60%) rolling deformation can be achieved, effectively avoiding the oxidation problem of sheets rolled at medium and high temperatures, as well as the easy cracking problem of conventional base surface textured magnesium alloy sheets under low temperature rolling conditions.

[0024] 3. In the process of low-temperature rolling deformation with large deformation, the temperature of the upper and lower rolls is controlled separately (the temperature of the rolls closer to the AZ-based magnesium alloy plate is lower than that of the rolls closer to the pure tantalum plate), so as to reduce the plasticity difference between the AZ-based magnesium alloy plate and the pure tantalum plate and enhance the coordinated deformation ability of the interface between the two during the low-temperature rolling process.

[0025] 4. This invention employs both cryogenic liquid nitrogen treatment and low-temperature recovery annealing, which effectively releases residual stress within the deformed sheet while significantly reducing plastic instability (shear bands, vacancies, cracks, etc.) at the interface of the deformed sheet, thus ensuring the smooth progress of subsequent low-temperature rolling deformation with large deformation.

[0026] 5. This invention achieves a certain degree of mutual "nesting and pressing" (mechanical bonding) and a certain degree of atomic diffusion layer (metallurgical bonding) at the plate interface through only two passes of high-deformation low-temperature rolling deformation. Subsequently, during high-temperature diffusion annealing, rapid atomic diffusion is achieved under the action of the intermediate aluminum plate, further enhancing the metallurgical bonding, ultimately forming a plate interface where mechanical and metallurgical bonding coexist harmoniously. This invention has no special requirements for rolling equipment, is applicable to a wide range of magnesium alloy plates, and is conducive to large-scale industrial applications.

[0027] 6. In the cryogenic treatment process of this invention, the liquid nitrogen used is a by-product of the oxygen production industry. It is inexpensive, widely available, energy-saving, easy to store and transport, chemically stable, non-toxic and pollution-free, and extremely low in cost. Attached Figure Description

[0028] Figure 1 This is a flowchart of the preparation method of the Mg-Al-Ta composite plate with good interfacial bonding as described in this invention. Detailed Implementation

[0029] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of the embodiments of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this invention, and not all embodiments. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention.

[0030] Example 1: A method for preparing a Mg-Al-Ta composite board with good interfacial bonding, comprising the following steps:

[0031] S1. Raw material preparation, including a pure tantalum plate with an initial thickness of 1.5 mm and a purity of 99.95%, an AZ31 magnesium alloy plate with a bimodal separation non-basal surface texture and an initial thickness of 1.5 mm, and a 1060 aluminum plate with an initial thickness of 0.1 mm. All the above plates are in the annealed state. The chemical composition of the AZ31 magnesium alloy plate and the intermediate 1060 aluminum plate should comply with the provisions of national standards GB / T5153-2016 and GB / T3190-2020. The selected pure tantalum plate and the AZ-series magnesium alloy plate with bimodal separation non-basal surface texture are surface ground for 3 min and 5 min respectively using an angle grinder, followed by subsequent pickling and acetone / alcohol cleaning to remove surface oxides and inclusions.

[0032] S2, the raw materials are stacked and fixed in the order of magnesium alloy plate, aluminum plate and pure tantalum plate to obtain the rolled billet.

[0033] S3, the rolled billet is rolled and deformed to obtain a deformed sheet. The rolling temperature is 110℃, the thinning rate per rolling pass is 45%, the speed of the upper and lower rolls is 300m / min, the temperature of the rolls near the AZ-based magnesium alloy plate is 120℃, and the temperature of the rolls near the pure tantalum plate is 180℃.

[0034] S4. First, the deformed sheet material is immersed in liquid nitrogen for cryogenic treatment for 75 minutes. Then, it undergoes low-temperature recovery annealing at 140°C for 45 minutes, with cooling either in-furnace cooling or external cooling, to obtain the heat-treated sheet material.

[0035] S5, the heat-treated sheet is rolled and deformed to obtain a secondary deformed sheet. The rolling temperature is 180℃, the thinning rate per rolling pass is 50%, the speed of the upper and lower rolls is 420m / min, the temperature of the rolls near the AZ-based magnesium alloy plate is 160℃, and the temperature of the rolls near the pure tantalum plate is 250℃.

[0036] S6. The secondary deformed plate is subjected to high-temperature diffusion annealing treatment with a uniform pressure of 0.04 MPa, a diffusion annealing temperature of 450℃, and a diffusion annealing time of 1.0 h to obtain a Mg-Al-Ta composite plate with good interfacial bonding.

[0037] Comparative Example 1: The preparation method of the Mg-Al-Ta composite plate with good interfacial bonding described in this comparative example is the same as that in Example 1, except that the AZ31 magnesium alloy plate selected as the raw material has a base surface texture feature.

[0038] Comparative Example 2: The preparation method of the Mg-Al-Ta composite plate with good interfacial bonding described in this comparative example is the same as that in Example 1, except that the intermediate 1060 aluminum alloy sheet is not used in the material.

[0039] Comparative Example 3: The preparation method of the Mg-Al-Ta composite plate with good interfacial bonding described in this comparative example is the same as that in Example 1, except that the cryogenic liquid nitrogen treatment was not performed in S4.

[0040] Comparative Example 4: The preparation method of the Mg-Al-Ta composite board with good interfacial bonding described in this comparative example is the same as that in Example 1, except that low-temperature recovery annealing treatment was not performed in S4.

[0041] The surface quality and field emission electron microscopy (SEM) observation of the prepared Mg-Al-Ta composite plate showed that the surface quality of the composite plate prepared in Example 1 was good, there were no obvious cracks at the edge of the plate, the diffusion width of the Mg-Al-Ta composite plate interface was 6.4 μm, and the interface bonding was good.

[0042] In Comparative Example 1, after the first pass of low-temperature rolling deformation with large deformation, obvious edge cracks appeared at the edge of the magnesium plate, and subsequent deformation could not be carried out. This indicates that the use of bimodal separation non-basal textured AZ31 magnesium alloy plate is the key factor for the successful preparation of Mg-Al-Ta composite plate in this invention.

[0043] The composite plate prepared in Comparative Example 2 has good surface quality, with no obvious cracks at the edge of the plate. The diffusion width at the interface of the Mg-Al-Ta composite plate is 2.6 μm, indicating that the presence of the 1060 aluminum alloy thin plate in the middle layer significantly enhances the interfacial bonding performance of the prepared composite plate.

[0044] The composite plate prepared in Comparative Example 3 had good surface quality, but cracks appeared at the edge of the plate. The diffusion width at the interface of the Mg-Al-Ta composite plate was 4.5 μm, indicating that cryogenic liquid nitrogen treatment was the key factor for the successful preparation of the Mg-Al-Ta composite plate in this invention.

[0045] The surface quality of the composite plate prepared in Comparative Example 4 was generally poor, with many cracks appearing at the edges of the plate. The diffusion width at the interface of the Mg-Al-Ta composite plate was 4.9 μm, indicating that low-temperature recovery annealing was the key factor for the successful preparation of the Mg-Al-Ta composite plate in this invention.

[0046] Example 2: A method for preparing a Mg-Al-Ta composite board with good interfacial bonding, comprising the following steps:

[0047] S1. Raw material preparation, including a pure tantalum plate with an initial thickness of 2.0 mm and a purity of 99.95%, an AZ31 magnesium alloy plate with a bimodal separation non-basal surface texture and an initial thickness of 2.0 mm, and a 1060 aluminum plate with an initial thickness of 0.2 mm. All the above plates are in the annealed state. The chemical composition of the AZ31 magnesium alloy plate and the intermediate 1060 aluminum plate should comply with the provisions of national standards GB / T5153-2016 and GB / T3190-2020. The selected pure tantalum plate and the AZ-series magnesium alloy plate with bimodal separation non-basal surface texture are surface ground for 5 min and 8 min respectively using an angle grinder, followed by subsequent pickling and acetone / alcohol cleaning to remove surface oxides and inclusions.

[0048] S2, the raw materials are stacked and fixed in the order of magnesium alloy plate, aluminum plate and pure tantalum plate to obtain the rolled billet.

[0049] S3, the rolled billet is rolled and deformed to obtain a deformed sheet. The rolling temperature is 140℃, the thinning rate per rolling pass is 40%, the speed of the upper and lower rolls is 400m / min, the temperature of the rolls near the AZ-based magnesium alloy plate is 150℃, and the temperature of the rolls near the pure tantalum plate is 220℃.

[0050] S4. First, the deformed sheet material is immersed in liquid nitrogen for cryogenic treatment for 120 minutes. Then, it undergoes low-temperature recovery annealing at 170°C for 60 minutes, with cooling either in-furnace cooling or external cooling, to obtain the heat-treated sheet material.

[0051] S5, the heat-treated sheet is rolled and deformed to obtain a secondary deformed sheet. The rolling temperature is 200℃, the thinning rate per rolling pass is 45%, the speed of the upper and lower rolls is 480m / min, the temperature of the rolls near the AZ-based magnesium alloy plate is 200℃, and the temperature of the rolls near the pure tantalum plate is 300℃.

[0052] S6. The secondary deformed plate is subjected to high-temperature diffusion annealing treatment with a uniform pressure of 0.07 MPa, a diffusion annealing temperature of 480℃, and a diffusion annealing time of 2.0 h to obtain a Mg-Al-Ta composite plate with good interfacial bonding.

[0053] The surface quality and field emission electron microscopy (SEM) observation of the prepared Mg-Al-Ta composite plate showed that the surface quality of the composite plate prepared in Example 2 was good, there were no obvious cracks at the edge of the plate, the diffusion width of the Mg-Al-Ta composite plate interface was 7.9 μm, and the interface bonding was good.

[0054] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A method for preparing a Mg-Al-Ta composite plate with good interfacial bonding, characterized in that, Includes the following steps: S1, Raw material preparation, including pure tantalum plate, AZ-series magnesium alloy plate with bimodal separation non-basal surface texture, and aluminum plate; S2, the raw materials are stacked and fixed in the order of magnesium alloy plate, aluminum plate and pure tantalum plate to obtain the rolled billet; S3, the rolled billet is rolled and deformed to obtain a deformed plate; the specific process parameters for rolling and deformation are: rolling temperature is 100~150℃, thinning rate per rolling pass is 40~60%, rolling temperature of the rolls near the AZ-based magnesium alloy plate is 100~160℃, and rolling temperature of the rolls near the pure tantalum plate is 180~250℃. S4. First, the deformed sheet is immersed in liquid nitrogen for cryogenic treatment for 60-360 minutes. Then, it is subjected to low-temperature recovery annealing treatment. The annealing temperature of the low-temperature recovery annealing treatment is 100-180°C and the annealing time is 30-75 minutes. The cooling method is furnace cooling or external cooling to obtain the heat-treated sheet. S5, the heat-treated sheet is rolled and deformed to obtain a secondary deformed sheet; the specific process parameters for rolling and deformation are: rolling temperature of 150~200℃, thinning rate of rolling pass of 40~60%, rolling temperature of the rolls near the AZ-based magnesium alloy plate of 150~200℃, and rolling temperature of the rolls near the pure tantalum plate of 220~300℃. S6. The secondary deformed plate is subjected to high-temperature diffusion annealing treatment. The uniform pressure of the high-temperature diffusion annealing treatment is 0.03~0.10MPa, the diffusion annealing temperature is 400~480℃, and the diffusion annealing time is 1.0~4.5h, to obtain a Mg-Al-Ta composite plate with good interfacial bonding.

2. A Mg-Al-Ta composite material with good interfacial bonding, characterized in that: The Mg-Al-Ta composite material with good interfacial bonding as described in claim 1 was prepared.

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