CN115491559A - Rare earth magnesium alloy and preparation method thereof - Google Patents
Rare earth magnesium alloy and preparation method thereof Download PDFInfo
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- 229910052761 rare earth metal Inorganic materials 0.000 title claims abstract description 91
- 229910000861 Mg alloy Inorganic materials 0.000 title claims abstract description 77
- 150000002910 rare earth metals Chemical class 0.000 title claims abstract description 69
- 238000002360 preparation method Methods 0.000 title claims abstract description 13
- 229910045601 alloy Inorganic materials 0.000 claims abstract description 69
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- 239000011777 magnesium Substances 0.000 claims abstract description 51
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Classifications
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C23/00—Alloys based on magnesium
- C22C23/06—Alloys based on magnesium with a rare earth metal as the next major constituent
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C1/00—Making non-ferrous alloys
- C22C1/02—Making non-ferrous alloys by melting
- C22C1/03—Making non-ferrous alloys by melting using master alloys
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22F—CHANGING THE PHYSICAL STRUCTURE OF NON-FERROUS METALS AND NON-FERROUS ALLOYS
- C22F1/00—Changing the physical structure of non-ferrous metals or alloys by heat treatment or by hot or cold working
- C22F1/02—Changing the physical structure of non-ferrous metals or alloys by heat treatment or by hot or cold working in inert or controlled atmosphere or vacuum
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22F—CHANGING THE PHYSICAL STRUCTURE OF NON-FERROUS METALS AND NON-FERROUS ALLOYS
- C22F1/00—Changing the physical structure of non-ferrous metals or alloys by heat treatment or by hot or cold working
- C22F1/06—Changing the physical structure of non-ferrous metals or alloys by heat treatment or by hot or cold working of magnesium or alloys based thereon
Abstract
The invention relates to a rare earth magnesium alloy and a preparation method thereof, belonging to the technical field of metal materials. The general formula of the rare earth alloy is Mg-Gd-Nd, and the rare earth magnesium alloy comprises the following components in percentage by mass: gd is between 1 and 3 percent, nd is between 1 and 3 percent, and the balance is Mg and some inevitable impurity elements. According to the invention, the rare earth magnesium alloy is processed by hot extrusion, the three-dimensional stress during hot extrusion can inhibit the crack from growing, so that the magnesium alloy is completely extruded, the crystal grains can be refined, and the internal structure is more uniform. The rare earth magnesium alloy prepared by the method has weaker basal plane texture strength, lower anisotropy, difficult dynamic instability in the compression process, plasticity of more than 40 percent at room temperature, and ultimate strength of 280MPa, and the good comprehensive mechanical property makes the wide application possible.
Description
Technical Field
The invention belongs to the technical field of metal materials, and particularly relates to a rare earth magnesium alloy and a preparation method thereof.
Background
In recent years, the international society has more stringent requirements on energy conservation and emission reduction, and as a green engineering structural material in the 21 st century, the magnesium alloy has better development prospect in the fields of aerospace, automobile industry, military industry and the like due to low density, high specific strength and specific stiffness, good damping and shock absorption and excellent electromagnetic shielding performance.
Magnesium has an HCP structure, the crystal symmetry is poor, the < a > type slip can only provide 4 independent slip systems, the requirements of at least five independent slip systems required by polycrystalline body for uniform plastic deformation cannot be met, and the < a > type slip cannot coordinate the strain of the alloy in the c-axis direction, so that the magnesium alloy has poor plastic deformation capability at room temperature and is easy to have brittle fracture. In addition, magnesium has high chemical activity, low equilibrium potential, is susceptible to galvanic corrosion when in contact with various metals, and serves as an anode. At room temperature, the magnesium surface reacts with oxygen in the air to form a magnesium oxide film, but since the magnesium oxide film is relatively loose, its densification factor is only 0.79, i.e., the volume of magnesium oxide formed after magnesium oxidation is reduced, and therefore the corrosion resistance is poor.
The refined crystal grains are particularly important for improving the microstructure and the mechanical property of the magnesium alloy, the critical shear stress of the < c + a > slippage can be reduced by the refinement of the crystal grains of the magnesium alloy, and the plastic deformation capability of the alloy can be greatly improved by the starting of the < c + a > slippage. The rare earth element is used as a surface activation element, and the surface tension of fluid can be reduced in the alloy casting process, so that the critical nucleation work is reduced, the number of crystal cores is increased, the supercooling degree of the alloy can be increased, and the growth of crystal grains is hindered, so that the crystal grains are refined.
The rare earth resources in China are rich, and the development of the rare earth magnesium alloy with excellent performance has great advantages. Gd is a heavy rare earth element which is widely concerned in recent years, and has larger solid solubility in magnesium, and the solid solubility is rapidly reduced along with the reduction of temperature, so that supersaturated solid solution is easily formed, therefore, the Mg-Gd series alloy has better solid solution strengthening and precipitation strengthening effects, and part of the rare earth element is dissolved in the magnesium alloy matrix to strengthen crystal grains, increase the dislocation slip resistance and improve the alloy strength. The other part and magnesium form a high-temperature stable intermetallic compound which is dispersed and distributed in the alloy to play a role in strengthening. In addition, rare earthThe composite addition of the elements can also reduce the solid solubility of the elements in the magnesium matrix, change the kinetic process of aging precipitation of the opposite side from the magnesium matrix and increase the strengthening effect, and Nd serving as a light rare earth element can be combined with O at the grain boundary to generate Nd 2 O 3 The passive film obviously improves the corrosion resistance of the alloy, can also reduce the density and the cost of the alloy and improve the deformation processing performance of the alloy.
The traditional magnesium alloy is usually prepared by adopting a casting process, but the casting performance of the magnesium alloy is poor, and various defects such as looseness, slag inclusion, cracks, air holes and the like are easy to appear in the production of castings of the magnesium alloy and are difficult to eliminate. Therefore, how to solve various defects generated after casting of the rare earth magnesium alloy becomes the research focus of the invention.
Disclosure of Invention
Aiming at the problems that the plasticity, corrosion resistance and other properties of the existing magnesium alloy are poor and casting technology can bring various defects such as looseness, cracks and the like, the invention provides the rare earth magnesium alloy and the preparation method thereof. In addition, the invention utilizes the hot extrusion process to inhibit the generation of alloy cracks after casting, reduces the deformation resistance and improves the plasticity of the magnesium alloy.
The technical scheme adopted by the invention is as follows:
the preparation method of the rare earth magnesium alloy is characterized by comprising the following steps:
1) Preparing materials: selecting Mg and Mg rare earth intermediate alloy Mg-25wt% Gd and Mg-25wt% Nd as raw materials, and calculating and weighing the raw materials according to the mass percentage of each component after removing oxide skin; wherein, the mass percent of each component is between 1 and 3 percent of Gd, between 1 and 3 percent of Nd, between 0.002 percent of Fe, between 0.005 percent of Si and the balance of Mg;
2) Smelting: adding the weighed Mg blocks into a graphite crucible furnace, and reacting in SF 6 +CO 2 Heating the Mg block to melt under the protection of atmosphere, adding Mg-25wt% of Mg-rare earth master alloy, gd, mg-25 w%t% of Nd, and continuously heating until the Nd is completely melted; after removing scum, raising the temperature in the furnace to 983K-1000K, and preserving the temperature to obtain molten rare earth magnesium alloy;
3) Casting: selecting a crystallization mold, preheating the mold, and pouring the molten rare earth magnesium alloy obtained in the step 2) into the mold for casting to obtain an as-cast rare earth magnesium alloy;
4) Solution treatment: removing oxide skin of the as-cast rare earth magnesium alloy obtained in the step 3), then carrying out solid solution under the protection of argon atmosphere, and cooling the as-cast rare earth magnesium alloy to room temperature after the solid solution is finished;
5) Hot extrusion: and heating the as-cast rare earth magnesium alloy again to an extrusion temperature of 628K-733K, preserving the heat, and then carrying out hot extrusion to obtain the rare earth magnesium alloy plate which is subjected to hot extrusion deformation and is cooled to room temperature.
Further, the purity of Mg selected in step 1) is greater than or equal to 99.9wt.%.
Furthermore, in the step 1), the mass percentage of each component is between 3% and 5% of Gd, between 3% and 5% of Nd, between 0.002% of Fe, between 0.005% of Si and the balance of Mg.
Further, the heat preservation time in the step 2) is 0.25-0.5 h.
Further, in the step 3), the casting manner is direct cooling type semi-continuous casting.
Further, in the step 4), the solid solution temperature is 763K to 778K, the solid solution time is 15 to 18 hours, and the cooling mode is water cooling.
Further, the heat preservation time before hot extrusion in the step 5) is 0.5-1 h, and the cooling mode after hot extrusion is water cooling.
Further, the extrusion ratio of the rare earth magnesium alloy plate in the hot extrusion deformation process in the step 5) is 5-10.
Further, the rare earth magnesium alloy plate after being subjected to hot extrusion deformation and cooled to room temperature in the step 5) needs to be subjected to straightening treatment by a pressure straightener.
The rare earth magnesium alloy prepared by any one of the preparation methods is characterized in that when the extrusion temperature is 653K, the maximum compressive stress of the prepared rare earth magnesium alloy plate is 278MPa; when the extrusion temperature is 723K, the maximum compressive stress of the prepared rare earth magnesium alloy plate is 228MPa.
The invention has the following beneficial effects:
1. the rare earth elements Gd and Nd have higher solid solubility in magnesium, and rare earth atoms are dissolved in a magnesium matrix, so that the atom diffusion rate can be slowed down, and dislocation movement is hindered, thereby strengthening the matrix and improving the strength and high-temperature creep property of the alloy; the rare earth elements can form a compact composite oxide film on the surface of the melt, so that the contact between the melt and the atmosphere is effectively prevented, and the oxidation resistance and the corrosion resistance of the material are improved.
2. The hot extrusion processing is in a three-dimensional pressure stress state, so that the initiation of cracks can be inhibited, the magnesium rare earth alloy is completely extruded, the density of an internal structure is improved, and the internal structure is more uniform. And the hot extrusion temperature is generally higher than the recrystallization temperature, so that the magnesium rare earth alloy can be dynamically recrystallized in the hot extrusion process, thereby obtaining a uniform and fine isometric crystal structure. After hot extrusion, the compressive strength and the fracture strain of the alloy can be improved by 46 percent to the maximum extent, the plasticity of the alloy is over 40 percent at room temperature, and the maximum true stress of room-temperature equal-strain-rate compression can reach 278MPa.
3. The hot extrusion operation is simple, the productivity is high, the material utilization rate is high, the total cost is lower, the continuous forming can be realized, the production efficiency is favorably improved, and the application of the magnesium rare earth alloy in engineering structure materials is expanded.
4. After hot extrusion, the magnesium rare earth alloy inevitably has a certain degree of curvature, and the sectional material also has the defects of distortion, flaring, parallel opening, clearance and the like, and the main reasons are that the magnesium rare earth alloy has uneven flow, uneven stress change in the alloy and bending and distortion of the product, so that straightening treatment is needed to avoid the defects, the tensile strength and the yield strength of the alloy after the straightening treatment are improved to a certain degree, and the internal stress is eliminated or reduced.
Drawings
FIG. 1 is a microstructure of a rare earth magnesium alloy after casting in example 1 of the present invention.
FIG. 2 is a microstructure morphology of the rare earth magnesium alloy after hot extrusion deformation in example 1 of the present invention.
FIG. 3 is an XRD contrast pattern of the alloy after casting and after hot extrusion deformation in example 1 of the present invention.
FIG. 4 is a graph comparing the true stress-strain curves of the alloys after casting and after hot extrusion deformation at room temperature equal strain rate compression in example 1 of the present invention.
FIG. 5 is a microstructure of the rare earth magnesium alloy after hot extrusion in example 2 of the present invention.
FIG. 6 is an XRD contrast of the alloy after casting and after hot extrusion deformation in example 2 of the present invention.
FIG. 7 is a graph comparing the true stress-strain curves of the alloys after casting and after hot extrusion deformation at room temperature equal strain rate compression in example 2 of the present invention.
Detailed Description
The invention will be further described with reference to the following figures and specific examples, but the scope of the invention is not limited thereto.
Example 1
The preparation steps of the rare earth magnesium alloy in the embodiment are as follows:
step S1: preparing Mg and Mg-rare earth intermediate alloy Mg-25wt% Gd and Mg-25wt% Nd as raw materials, before weighing, descaling the raw materials by 200-mesh sand paper, heating to remove water vapor of the raw materials, and then calculating and weighing according to the mass percentage of each component, wherein the purity of Mg is more than or equal to 99.9wt%, and the mass percentage of each component in the prepared rare earth magnesium alloy is Gd:1.5%, nd:1.5%, fe:0.001%, si:0.002%, and the balance Mg, but considering that the rare earth elements Gd and Nd will be burned out in the preparation process, the present embodiment increases the mass percentage of the rare earth elements Gd and Nd when calculating the raw material ratio, and finally, the ratio of Gd:3.5%, nd:3.5%, fe:0.001%, si:0.002% and the balance of Mg.
Step S2: adding weighed Mg into a graphite crucible, and adding the Mg into SF 6 +CO 2 Under the protection of atmosphere, firstly, M is addedg heating to 973K, after Mg melts, adding Mg-25wt% Gd and Mg-25wt% Nd of the magnesium rare earth master alloy until all melts, removing dross, raising the temperature to 993K, and standing for 0.25h, thereby reducing oxide inclusions formed in the melting process.
And step S3: and (3) pouring the molten alloy obtained in the step (S2) into a pre-preheated crystallization mold, and performing direct-cooling type semi-continuous casting by using a casting machine at a casting speed of 100mm/min to obtain the as-cast rare earth magnesium alloy.
Polishing a cast-state rare earth magnesium alloy sample on waterproof abrasive paper smoothly, firstly, roughly polishing a gold velvet polishing cloth coated with 2.5 mu m diamond polishing paste, then finely polishing the gold velvet polishing cloth by using magnesium oxide suspension until the surface has no scratch or polishing mark, then shooting the microscopic appearance of the alloy by using a field emission scanning electron microscope, and then carrying out X-ray diffraction (XRD) analysis on the cast-state magnesium rare earth alloy, wherein an X-ray source adopts Cu Kalpha rays, the scanning angle 2 theta is 20-90 degrees, and the scanning speed is 5 DEG/min. And performing equal strain rate compression at room temperature to draw a true stress-strain curve graph.
And step S4: and (4) removing the oxide skin on the surface layer of the as-cast rare earth magnesium alloy obtained in the step (S3) by turning, processing the alloy into a cylindrical blank, carrying out solid solution for 16h under the protection of 773K and argon atmosphere, fully diffusing element atoms to obtain a uniform structure, and cooling the alloy to room temperature after the solid solution is finished.
Step S5: and heating the cooled as-cast rare earth magnesium alloy to 653K, keeping the temperature for 50min to uniformly heat the alloy ingot, and extruding the alloy ingot at the extrusion speed of 1mm/s by a 630-ton horizontal extruder to finally obtain the deformed alloy plate with the extrusion ratio of 8. Because the hot extrusion temperature is higher than the recrystallization temperature, the alloy can be dynamically recrystallized in the hot extrusion process, so that a uniform and fine isometric crystal structure is obtained. And cooling with flowing water at the alloy extrusion position so as to better retain the high-temperature deformation structure and enable the extruded alloy to have a higher-quality surface.
Step S6: and (4) cooling the extrusion plate to room temperature, and then treating the material by using a pressure straightener to obtain the rare earth magnesium alloy after hot extrusion deformation. And performing scanning electron microscope analysis and X-ray diffraction (XRD) analysis on the rare earth magnesium alloy after the hot extrusion deformation, performing equal strain rate compression at room temperature, and drawing a true stress-strain curve, wherein the operation steps and various measurement parameters are consistent with those in the step S3.
The actual mass percentage of the finally obtained rare earth magnesium alloy is analyzed by using an X-ray photoelectron spectroscopy technology (XPF), and the alloy is measured to contain 1.487% of Gd,1.511% of Nd,0.001% of Fe,0.002% of Si and the balance of Mg.
The microstructure of the as-cast alloy is shown in FIG. 1, and the alloy consists of a dark-colored portion of a magnesium matrix and a light-colored portion of a semi-continuous network and granular compound of magnesium and rare earth. FIG. 2 shows the SEM morphology of the rare earth magnesium alloy after hot extrusion deformation in example 1, after hot extrusion, the alloy is composed of equiaxed grains and fine recrystallized grains, and shows the structural feature of alternating large and small grains, a small amount of second phase is present in the structure and is dispersedly distributed in the grain boundary or intragranular equiaxed grain structure, the grains are obviously refined compared with the as-cast alloy, the reticular second phase is extruded and crushed into fine grains and is uniformly distributed in the structure, and the reticular Mg5RE phase is transformed into a granular phase after extrusion by combining with the XRD pattern of FIG. 3 and the records of related documents. FIG. 4 is a graph of compressive stress and strain for an alloy, which shows that the compressive strength and the strain at break of the alloy are improved by 20% compared to the cast alloy after hot extrusion, and the maximum compressive stress that can be sustained by the alloy can reach 278MPa.
Example 2
The preparation steps of the rare earth magnesium alloy in the embodiment are as follows:
step S1: preparing Mg and Mg-rare earth intermediate alloy Mg-25wt% Gd and Mg-25wt% Nd as raw materials, before weighing, descaling the raw materials by 200-mesh sand paper, heating to remove water vapor of the raw materials, and then calculating and weighing according to the mass percentage of each component, wherein the purity of Mg is more than or equal to 99.9wt%, and the mass percentage of each component in the prepared rare earth magnesium alloy is Gd:1.5%, nd:1.5%, fe:0.001%, si:0.002%, and the balance Mg, but considering that the rare earth elements Gd and Nd will be burned during the preparation process, the mass percentage of the rare earth elements Gd and Nd is increased during the calculation of the raw material ratio in this embodiment, and finally, the ratio of Gd:3.5%, nd:3.5%, fe:0.001%, si:0.002% and the balance of Mg.
Step S2: adding weighed Mg into a graphite crucible in SF 6 +CO 2 Under the protection of atmosphere, mg is heated to 973K, after Mg is melted, gd and Nd are added into the Mg-rare earth intermediate alloy according to the proportion of Mg-25wt% and the proportion of Mg-25wt% until the Mg is completely melted, the temperature is raised to 993K after scum is removed, and the mixture is kept stand for 0.25h, so that oxide inclusions formed in the melting process are reduced.
And step S3: and finally pouring the mixture into a pre-preheated crystallization mold, and carrying out direct-cooling type semi-continuous casting by using a casting machine at the casting speed of 100mm/min to obtain the as-cast rare earth magnesium alloy.
Polishing a cast-state rare earth magnesium alloy sample on waterproof abrasive paper smoothly, firstly, roughly polishing a gold velvet polishing cloth coated with 2.5 mu m diamond polishing paste, then, finely polishing the gold velvet polishing cloth by using magnesium oxide suspension until the surface has no scratch or polishing mark, then, shooting the alloy microscopic appearance by using a field emission scanning electron microscope, and then, carrying out X-ray diffraction (XRD) analysis on the cast-state magnesium rare earth alloy, wherein an X-ray source adopts Cu Kalpha rays, the scanning angle 2 theta is 20-90 degrees, and the scanning speed is 5 DEG/min; and performing equal strain rate compression at room temperature to draw a true stress-strain curve graph.
And step S4: and (4) removing the oxide skin on the surface layer of the as-cast rare earth magnesium alloy obtained in the step (S3) by turning, processing the alloy into a cylindrical blank, carrying out solid solution for 16h under the protection of 773K and argon atmosphere, fully diffusing element atoms to obtain a uniform structure, and cooling the alloy to room temperature after the solid solution is finished.
Step S5: and heating the cooled as-cast rare earth magnesium alloy to 723K, preserving heat for 50min to uniformly heat the alloy ingot, and extruding at the extrusion speed of 1mm/s by a 630-ton horizontal extruder to obtain the deformed alloy plate with the extrusion ratio of 8. Because the hot extrusion temperature is higher than the recrystallization temperature, the alloy can be dynamically recrystallized in the hot extrusion process, so that a uniform and fine isometric crystal structure is obtained. And then cooling with flowing water at the alloy extrusion position so as to better retain the high-temperature deformation structure and enable the extruded alloy to have a surface with higher quality.
Step S6: and (3) cooling the extrusion plate to room temperature, and then treating the material by using a pressure straightener to obtain the required rare earth magnesium alloy after hot extrusion deformation. And performing scanning electron microscope analysis and X-ray diffraction (XRD) analysis on the rare earth magnesium alloy after the hot extrusion deformation, performing equal strain rate compression at room temperature, and drawing a true stress-strain curve, wherein the operation steps and various measurement parameters are consistent with those in the step S3.
The actual mass percentage of the finally obtained rare earth magnesium alloy is analyzed by using an X-ray photoelectron spectroscopy technology (XPF), and the alloy is measured to contain 1.487% of Gd,1.511% of Nd,0.001% of Fe,0.015% of Si and the balance of Mg.
Fig. 5 shows the SEM morphology of the rare earth magnesium alloy after hot extrusion in example 2, after hot extrusion, the alloy is composed of equiaxed grains and fine recrystallized grains, and exhibits the structural feature of alternating large and small grains, a small amount of second phase is present in the structure and is dispersedly distributed in the grain boundary or intragranular equiaxed grain structure, the grains are significantly refined compared with the as-cast alloy, the reticular second phase is crushed by extrusion into fine particles and is uniformly distributed in the structure, and similar to example 1, in combination with the XRD pattern of fig. 6 and the related literature, the reticular Mg5RE phase is transformed into a particle phase after extrusion. As can be seen from the compressive stress strain plot 7 of the alloy, the fracture strain of the alloy increased by 46% after hot extrusion compared to the cast alloy.
The present invention is not limited to the above-described embodiments, and any obvious improvements, substitutions or modifications can be made by those skilled in the art without departing from the spirit of the present invention.
Claims (10)
1. The preparation method of the rare earth magnesium alloy is characterized by comprising the following steps:
1) Preparing materials: selecting Mg, mg rare earth intermediate alloy Mg-25wt% Gd, mg-25wt% Nd as raw material, removing oxide skin, calculating and weighing the raw material according to the mass percentage of each component; wherein, the mass percent of each component is between 1 and 3 percent of Gd, between 1 and 3 percent of Nd, between 0.002 percent of Fe, between 0.005 percent of Si and the balance of Mg;
2) Smelting: adding the weighed Mg blocks into a graphite crucible furnace, and reacting in SF 6 +CO 2 Under the protection of atmosphere, heating the Mg block to be molten, adding Mg-25wt% of Mg-rare earth intermediate alloy, namely Gd and Mg-25wt% of Nd, and continuously heating until the Mg block is completely molten; after removing scum, raising the temperature in the furnace to 983K-1000K, and preserving the temperature to obtain molten rare earth magnesium alloy;
3) Casting: selecting a crystallization mold, preheating the mold, and pouring the molten rare earth magnesium alloy obtained in the step 2) into the mold for casting to obtain an as-cast rare earth magnesium alloy;
4) Solution treatment: removing oxide skin of the as-cast rare earth magnesium alloy obtained in the step 3), then carrying out solid solution under the protection of argon atmosphere, and cooling the as-cast rare earth magnesium alloy to room temperature after the solid solution is finished;
5) Hot extrusion: and heating the as-cast rare earth magnesium alloy again to an extrusion temperature of 628K-733K, preserving the heat, and then carrying out hot extrusion to obtain the rare earth magnesium alloy plate which is subjected to hot extrusion deformation and is cooled to room temperature.
2. The method for preparing a rare earth-magnesium alloy as claimed in claim 1, wherein the purity of Mg selected in step 1) is 99.9wt.% or more.
3. The method for preparing a rare earth magnesium alloy according to claim 1, wherein in the step 1), the mass percentage of each component is 3% to 5% of Gd, 3% to 5% of Nd, less than 0.002% of Fe, less than 0.005% of Si, and the balance of Mg.
4. The method for preparing rare earth-magnesium alloy according to claim 1, wherein the holding time in step 2) is 0.25 to 0.5h.
5. The method for preparing a rare earth-magnesium alloy as set forth in claim 1, wherein the casting in step 3) is direct-cooling type semi-continuous casting.
6. The method for preparing the rare earth magnesium alloy according to claim 1, wherein in the step 4), the solid solution temperature is 763K to 778K, the solid solution time is 15 to 18 hours, and the cooling mode is water cooling.
7. The method for preparing the rare earth magnesium alloy according to claim 1, wherein the heat preservation time before the hot extrusion in the step 5) is 0.5 to 1 hour, and the cooling mode after the hot extrusion is water cooling.
8. The method for preparing a rare earth magnesium alloy according to claim 1, wherein the extrusion ratio of the rare earth magnesium alloy sheet in the hot extrusion deformation process in the step 5) is 5 to 10.
9. The method for preparing a rare earth magnesium alloy as set forth in claim 1, wherein the rare earth magnesium alloy sheet after the hot extrusion deformation cooling to room temperature in the step 5) is further subjected to a straightening treatment by a pressure straightener.
10. The rare earth magnesium alloy prepared by the preparation method according to any one of claims 1 to 9, wherein the mass percentage of each component in the rare earth magnesium alloy is Gd:1.487%, nd:1.511%, fe:0.001%, si:0.015 percent and the balance of Mg; wherein the content error of Gd and Nd is +/-0.05 percent, and the content error of Fe and Si is +/-0.005 percent.
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| WO2005035811A1 (en) * | 2003-10-10 | 2005-04-21 | Magnesium Elektron Limited | Castable magnesium alloys |
| WO2005123972A1 (en) * | 2004-06-15 | 2005-12-29 | Toudai Tlo, Ltd. | High toughness magnesium-base alloy, drive component using same, and method for producing high toughness magnesium-base alloy material |
| CN108774703A (en) * | 2018-08-23 | 2018-11-09 | 中国科学院长春应用化学研究所 | A kind of high-strength light magnesium alloy and preparation method thereof containing Li |
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|---|---|---|---|---|
| WO2005035811A1 (en) * | 2003-10-10 | 2005-04-21 | Magnesium Elektron Limited | Castable magnesium alloys |
| WO2005123972A1 (en) * | 2004-06-15 | 2005-12-29 | Toudai Tlo, Ltd. | High toughness magnesium-base alloy, drive component using same, and method for producing high toughness magnesium-base alloy material |
| CN108774703A (en) * | 2018-08-23 | 2018-11-09 | 中国科学院长春应用化学研究所 | A kind of high-strength light magnesium alloy and preparation method thereof containing Li |
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| XIU-LI HOU ET AL.: "Rare earth texture analysis of rectangular extruded Mg alloys and a comparison of different alloying adding ways", RARE METALS * |
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Application publication date: 20221220 |