CN110042290B - High-elongation wrought magnesium alloy and preparation method thereof - Google Patents

Abstract

The invention provides a high-elongation wrought magnesium alloy and a preparation method thereof, wherein the high-elongation wrought magnesium alloy consists of the following elements in percentage by mass: 1.80 to 2.50 percent of Gd, 0.20 to 0.30 percent of Zn, 0.10 to 0.60 percent of Zr, 0.001 to 0.20 percent of Sc, 0.01 to 0.20 percent of Ti, and the balance of Mg and impurity elements; the preparation method comprises the following steps of taking raw materials according to selected mass percentage; mixing the raw materials, and then smelting and refining to obtain a melt; casting the melt to obtain a cast ingot; homogenizing the cast ingot and cutting into blanks; and carrying out hot working forming on the blank to obtain the high-elongation wrought magnesium alloy. According to the high-elongation deformation magnesium alloy and the preparation method thereof, a small amount of rare earth and other precious elements are added into the magnesium alloy, the magnesium alloy structure is refined, the elongation of the material is greatly improved under the condition that the cost of the material is improved in a small range, and the like, and the high-elongation deformation magnesium alloy is suitable for industrial application.

Description

High-elongation wrought magnesium alloy and preparation method thereof

Technical Field

The invention belongs to the technical field of metal material processing, and particularly relates to a high-elongation wrought magnesium alloy and a preparation method thereof.

Background

The magnesium alloy is the lightest metal structure material, has the characteristics of high specific strength, specific rigidity, electromagnetic shielding property, heat dissipation and the like, is easy to cut, process and recycle, and has better application prospect. At present, the magnesium alloy has wider application in the fields of electronics, vehicles, aerospace, oil and gas exploitation and the like.

According to the forming process, the magnesium alloy can be divided into cast magnesium alloy and wrought magnesium alloy, and the difference between the cast magnesium alloy and the wrought magnesium alloy in the aspects of structure and performance is large. Compared with cast magnesium alloy, the wrought magnesium alloy has finer and denser structure, and thus higher strength and elongation. However, because the magnesium alloy has a close-packed hexagonal crystal structure, the basal plane slip system is few at room temperature, and cannot meet the 5 independent slip system criteria required by mises theory coordinated deformation, so that the deformation is difficult, the elongation is generally lower than 20%, and the plasticity is poor compared with body-centered cubic and face-centered cubic metals. In the prior art, high-elongation magnesium alloy is generally obtained through high alloying, low-temperature deformation or large plastic deformation, and because more and expensive other elements are needed to form the alloy, or a more complex production process is needed, the production cost is high, and the industrial application prospect is poor.

Disclosure of Invention

The invention solves the technical problem of providing a high-elongation deformation magnesium alloy and a preparation method thereof, and the high-elongation deformation magnesium alloy has the advantages that precious elements such as rare earth are added into the magnesium alloy in a small amount, the magnesium alloy structure is refined, the elongation of the material is greatly improved under the condition of slightly improving the cost of the material and the like, and the high-elongation deformation magnesium alloy is suitable for industrial application.

In order to solve the problems, the invention provides a high-elongation wrought magnesium alloy which comprises the following elements in percentage by mass: 1.80 to 2.50 percent of Gd, 0.20 to 0.30 percent of Zn, 0.10 to 0.60 percent of Zr, 0.001 to 0.20 percent of Sc, 0.01 to 0.20 percent of Ti, and the balance of Mg and impurity elements.

The impurity element means an inevitable impurity element which is introduced from a raw material for preparing an alloy during the preparation of the alloy, i.e., a metal or a non-metal element which is present in a metal but is not intentionally added or retained, preferably, the mass percentage of the inevitable impurity element is 0 to 0.12%, and more preferably, the mass percentage of the impurity element is 0 to 0.10%.

Wherein, because the magnesium alloy belongs to a close-packed hexagonal crystal structure, basal plane slip systems are few at room temperature, and cannot meet the 5 independent slip system criteria required by mis theory coordinated deformation, the deformation is difficult, and the elongation is generally lower than 20%. Through theoretical calculation, the critical shear stress of cylindrical surface slip of the magnesium alloy is more than the critical shear stress of conical surface slip and more than the critical shear stress of basal surface slip. The critical shear stress of cylindrical surface slip of pure magnesium is about 100 times of basal surface slip, so that the alloy deformation performance is improved by improving the alloy conical surface slip. The proper amount of Gd element is added, so that the activation capability of the conical surface sliding system of the alloy can be obviously improved, and the elongation of the alloy is improved. Meanwhile, Gd and Zn are added, the Gd can be matched with the Zn, the ratio of c/a of the alloy is reduced, the cylindrical surface sliding system is activated, the cylindrical surface sliding system can be better activated by adding the Zn and the Gd with proper content, and the elongation of the alloy is greatly improved. In addition, the rare earth element Gd has the effects of flame retardance and oxidation resistance, and the ignition point of the alloy is improved. Therefore, the consumption of protective gas in the smelting process can be reduced; no atmosphere protection is needed in the homogenization treatment process; the extrusion process may employ a faster extrusion rate.

The solid solubility of Ti, Zr and Sc elements in the magnesium alloy is low, interaction occurs among the added Ti, Zr and Sc, magnesium alloy ingot casting grains can be obviously refined in a heterogeneous nucleation mode, ingot segregation is further reduced, the distribution of material components is more uniform, the plasticity of deformed magnesium alloy plates, profiles and the like is further improved, namely, a small amount of expensive elements are added in a Ti, Zr and Sc multi-element micro-alloying mode, the magnesium alloy structure is refined, and the elongation of the material is greatly improved under the condition that the cost of the material is improved in a small range and the like. Wherein, the addition of a proper amount of Zr and Ti can obviously reduce the addition of Sc and the material cost.

In the technical scheme, preferably, the high-elongation wrought magnesium alloy consists of the following elements in percentage by mass: 2.0 to 2.20 percent of Gd, 0.20 to 0.28 percent of Zn, 0.20 to 0.50 percent of Zr, 0.01 to 0.10 percent of Sc, 0.05 to 0.20 percent of Ti, and the balance of Mg and impurity elements.

Further preferably, the high-elongation wrought magnesium alloy consists of the following elements in percentage by mass: 2.20 percent of Gd, 0.25 percent of Zn, 0.30 percent of Zr, 0.05 percent of Sc, 0.20 percent of Ti, and the balance of Mg and impurity elements.

Another object of the present invention is to provide a method for preparing the above high-elongation wrought magnesium alloy, comprising the steps of:

s1, taking raw materials according to selected mass percentage;

s2, mixing the raw materials in the step S1, and then smelting and refining to obtain a melt;

s3, casting the melt in the step S2 to obtain a cast ingot;

s4, homogenizing the cast ingot in the step S3, and cutting the cast ingot into blanks;

and S5, carrying out hot-forming on the blank in the step S4 to obtain the high-elongation wrought magnesium alloy.

In the technical solution, preferably, step S1 specifically includes: taking pure Mg, pure Zn, Mg-Gd intermediate alloy, Mg-Zr intermediate alloy, Mg-Sc intermediate alloy and Zn-Ti intermediate alloy according to the selected mass percentage. The intermediate alloy can be selected from any commercially available intermediate alloy with any proportion, for example, Mg-30% Gd and Mg-30% Zr can be used as Mg-Gd and Mg-Zr can be used as Mg-30% Zr.

In the technical solution, preferably, step S2 specifically includes: mixing the raw materials, heating at the temperature of 720-740 ℃ in protective atmosphere, smelting for 40-60min, refining for 15-40min, heating to the temperature of 740-760 ℃ after refining, and standing for 20-60 min. More preferably, step S2 specifically includes: mixing the raw materials, heating at 730 deg.C in protective atmosphere, smelting for 60min, refining for 20min, heating to 760 deg.C after refining, and standing for 40 min. Among them, it is further preferable to stir for 5 to 15min, and more preferably, for 10min before refining.

Among them, it is preferable that the protective atmosphere is CO₂And SF₆The mixed gas of (3); further preferably, the protective atmosphere is CO₂And SF₆The volume ratio is (100-) -200): 1 in the proportion of the mixed gas; more preferably, the protective atmosphere is CO₂And SF₆The volume ratio is 200:1, in the ratio of 1.

In the technical solution, the temperature during the casting in the step S3 is preferably 680-740 ℃, and more preferably the temperature during the casting in the step S3 is 700 ℃.

In the technical solution, preferably, the homogenization treatment in step S4 specifically includes: the ingot is kept at 350-450 ℃ for 12-48 h. And after the homogenization treatment is finished, the air cooling mode is preferably selected in the cooling process. More preferably, the homogenization treatment specifically comprises: and keeping the temperature of the cast ingot at 400 ℃ for 24 h.

In the technical scheme, preferably, the hot working forming in the step S5 adopts extrusion forming, the extrusion temperature is 350-450 ℃, the extrusion ratio is 4-60, and the extrusion speed is 0.1-20 m/min. More preferably, the extrusion temperature is 350 ℃, the extrusion ratio is 8, and the extrusion speed is 10 m/min. By adopting the extrusion ratio, the extruder with smaller tonnage can be used for preparing bars, plates and profiles with larger sizes.

Compared with the prior art, the invention has the following beneficial effects:

1. according to the high-elongation wrought magnesium alloy disclosed by the embodiment of the invention, only a small amount of expensive rare earth Gd element and trace Zr, Sc and Ti elements are added, and the elongation of the alloy is greatly improved by regulating and controlling the addition amount of each element, so that the alloy cost is slightly increased, and the high-elongation wrought magnesium alloy is suitable for industrial application;

2. in the high-elongation deformation magnesium alloy, Gd element is added to remarkably increase the activation capability of a conical surface sliding system of the alloy and improve the elongation of the alloy, Zn and Gd can form interaction and are matched with each other, so that the c/a ratio is reduced, and proper amount of Zn and Gd is added to activate a cylindrical surface sliding system better through regulation and control of the addition amount of Zn and Gd, so that the elongation of the alloy is greatly improved;

3. in the high-elongation deformation magnesium alloy provided by the embodiment of the invention, the rare earth element Gd also has flame retardant and antioxidant effects, so that the ignition point of the alloy is improved, the consumption of protective gas in the smelting process can be reduced, no atmosphere protection is required in the homogenization treatment process, and the extrusion process can adopt a faster extrusion rate;

4. in the high-elongation wrought magnesium alloy disclosed by the embodiment of the invention, the solid solubility of Ti, Zr and Sc elements in the magnesium alloy is low, the added Ti, Zr and Sc interact with each other, magnesium alloy ingot casting grains can be obviously refined in a heterogeneous nucleation mode, further ingot segregation is reduced, the distribution of material components is more uniform, and the plasticity of wrought magnesium alloy plates, sections and the like is further improved, namely, a small amount of expensive elements are added in a multi-element Ti, Zr and Sc microalloying mode to refine the structure of the magnesium alloy, and the elongation of the material is greatly improved under the condition of improving the cost of the material in a small amplitude and the like; and due to the addition of a proper amount of Zr and Ti, the addition amount of Sc can be obviously reduced, and the material cost is reduced;

5. the high-elongation-percentage wrought magnesium alloy disclosed by the embodiment of the invention can be obtained by adopting smaller deformation and smaller extrusion ratio through a conventional hot forming process, so that the deformation resistance of the material in the processing process can be reduced, and the power consumption of equipment is reduced; and a small-tonnage device can be adopted to process a large-size product, so that the equipment investment is reduced.

Detailed Description

The technical solutions of the present invention will be described clearly and completely with reference to the following embodiments of the present invention, and it should be understood that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Example 1

The high-elongation wrought magnesium alloy comprises the following elements in percentage by mass: 2.20 percent of Gd, 0.25 percent of Zn, 0.30 percent of Zr, 0.05 percent of Sc, 0.20 percent of Ti, less than 0.10 percent of impurity elements and the balance of Mg.

The preparation method of the high-elongation wrought magnesium alloy comprises the following specific steps:

s1, taking a pure magnesium ingot, a pure zinc ingot, an Mg-Gd intermediate alloy, an Mg-Zr intermediate alloy, an Mg-Sc intermediate alloy and a Zn-Ti intermediate alloy according to selected mass percentages;

s2, mixing the raw materials in the step S1 in CO₂And SF₆Heating the mixed gas with the volume ratio of 200:1 at 730 ℃ in a protective atmosphere, smelting for 60min, stirring for 10min, refining for 20min, raising the temperature to 760 ℃ after refining, and standing for 40min to obtain a melt;

s3, casting the melt in the step S2 into a semi-continuous ingot at 700 ℃;

s4, homogenizing the cast ingot in the step S3, preserving heat for 24 hours at 400 ℃, then cooling by air cooling, cutting into blanks and peeling;

s5, placing the blank in the step S4 into an extruder, and extruding the blank into a bar under the conditions that the extrusion temperature is 350 ℃, the extrusion ratio is 8 and the extrusion speed is 10m/min to obtain the high-elongation deformation magnesium alloy.

Example 2

The high-elongation wrought magnesium alloy comprises the following elements in percentage by mass:

2.0% of Gd, 0.20% of Zn, 0.20% of Zr, 0.01% of Sc, 0.05% of Ti, less than 0.10% of impurity elements and the balance of Mg.

The method for preparing the high elongation wrought magnesium alloy in this example is the same as that of example 1.

Example 3

The high-elongation wrought magnesium alloy comprises the following elements in percentage by mass:

2.20 percent of Gd, 0.28 percent of Zn, 0.50 percent of Zr, 0.10 percent of Sc, 0.20 percent of Ti, less than 0.10 percent of impurity elements and the balance of Mg.

The method for preparing the high elongation wrought magnesium alloy in this example is the same as that of example 1.

Example 4

The high-elongation wrought magnesium alloy comprises the following elements in percentage by mass:

2.10 percent of Gd, 0.25 percent of Zn, 0.30 percent of Zr, 0.10 percent of Sc, 0.10 percent of Ti, less than 0.10 percent of impurity elements and the balance of Mg.

The method for preparing the high elongation wrought magnesium alloy in this example is the same as that of example 1.

Example 5

The high-elongation wrought magnesium alloy comprises the following elements in percentage by mass:

1.80 percent of Gd, 0.20 percent of Zn, 0.10 percent of Zr, 0.001 percent of Sc, 0.01 percent of Ti, less than 0.10 percent of impurity elements and the balance of Mg.

The method for preparing the high elongation wrought magnesium alloy in this example is the same as that of example 1.

Example 6

The high-elongation wrought magnesium alloy comprises the following elements in percentage by mass:

2.50% of Gd, 0.30% of Zn, 0.60% of Zr, 0.20% of Sc, 0.20% of Ti, less than 0.10% of impurity elements and the balance of Mg.

The method for preparing the high elongation wrought magnesium alloy in this example is the same as that of example 1.

Example 7

The high-elongation wrought magnesium alloy comprises the following elements in percentage by mass:

2.50% of Gd, 0.20% of Zn, 0.40% of Zr, 0.02% of Sc, 0.10% of Ti, less than 0.12% of impurity elements and the balance of Mg.

The preparation method of the high-elongation wrought magnesium alloy comprises the following specific steps:

s1, taking a pure magnesium ingot, a pure zinc ingot, an Mg-Gd intermediate alloy, an Mg-Zr intermediate alloy, an Mg-Sc intermediate alloy and a Zn-Ti intermediate alloy according to selected mass percentages;

s2, mixing the raw materials in the step S1 in CO₂And SF₆Heating the mixed gas with the volume ratio of 100:1 at 740 ℃ in a protective atmosphere, smelting for 40min, stirring for 12min, refining for 25min, heating to 750 ℃ after refining, and standing for 30min to obtain a melt;

s3, casting the melt in the step S2 into a semi-continuous ingot at 680 ℃;

s4, homogenizing the cast ingot in the step S3, preserving heat for 48 hours at 350 ℃, then cooling by air cooling, and then cutting into blanks and peeling;

s5, placing the blank in the step S4 into an extruder, and extruding the blank into a bar under the conditions that the extrusion temperature is 400 ℃, the extrusion ratio is 4 and the extrusion speed is 5m/min to obtain the high-elongation deformation magnesium alloy.

Example 8

The high-elongation wrought magnesium alloy comprises the following elements in percentage by mass: 1.80 percent of Gd, 0.30 percent of Zn, 0.50 percent of Zr, 0.20 percent of Sc, 0.08 percent of Ti, less than 0.11 percent of impurity elements and the balance of Mg.

The preparation method of the high-elongation wrought magnesium alloy comprises the following specific steps:

s1, taking a pure magnesium ingot, a pure zinc ingot, an Mg-Gd intermediate alloy, an Mg-Zr intermediate alloy, an Mg-Sc intermediate alloy and a Zn-Ti intermediate alloy according to selected mass percentages;

s2, mixing the raw materials in the step S1 in CO₂And SF₆Heating the mixed gas with the volume ratio of 200:1 at 720 ℃ in a protective atmosphere, smelting for 60min, stirring for 15min, refining for 40min, heating to 740 ℃ after refining, and standing for 60min to obtain a melt;

s3, casting the melt in the step S2 into a semi-continuous ingot at 700 ℃;

s4, homogenizing the cast ingot in the step S3, preserving heat for 12 hours at 450 ℃, then cooling by air cooling, cutting into blanks and peeling;

s5, placing the blank in the step S4 into an extruder, and extruding the blank into a bar under the conditions that the extrusion temperature is 380 ℃, the extrusion ratio is 20 and the extrusion speed is 10m/min to obtain the high-elongation deformation magnesium alloy.

Example 9

The high-elongation wrought magnesium alloy comprises the following elements in percentage by mass: 2.10 percent of Gd, 0.22 percent of Zn, 0.10 percent of Zr, 0.06 percent of Sc, 0.14 percent of Ti, less than 0.10 percent of impurity elements and the balance of Mg.

The method for preparing the high elongation wrought magnesium alloy in this example is the same as that of example 1.

Example 10

The high elongation wrought magnesium alloy of this example has the same elemental composition as example 9.

The preparation method of the high-elongation wrought magnesium alloy comprises the following specific steps:

s1, taking a pure magnesium ingot, a pure zinc ingot, an Mg-Gd intermediate alloy, an Mg-Zr intermediate alloy, an Mg-Sc intermediate alloy and a Zn-Ti intermediate alloy according to selected mass percentages;

s2, mixing the raw materials in the step S1 in CO₂And SF₆Heating the mixed gas with the volume ratio of 200:1 at 740 ℃ in a protective atmosphere, smelting for 40min, stirring for 15min, refining for 20min, raising the temperature to 760 ℃ after refining, and standing for 50min to obtain a melt;

s3, casting the melt in the step S2 into a semi-continuous ingot at 680 ℃;

s4, homogenizing the cast ingot in the step S3, preserving heat for 15 hours at 400 ℃, then cooling by air cooling, and then cutting into blanks and peeling;

s5, placing the blank in the step S4 into an extruder, and extruding the blank into a bar under the conditions that the extrusion temperature is 400 ℃, the extrusion ratio is 60 and the extrusion speed is 4m/min to obtain the high-elongation deformation magnesium alloy.

Comparative example 1

The magnesium alloy of the present comparative example was AZ31 magnesium alloy, which had the chemical composition: mg-3.0 wt% Al-0.80 wt% Zn-0.3 wt% Mn, the preparation method of the magnesium alloy of the comparative example is the same as that of the example 1, and the raw materials are as follows: pure magnesium ingot, pure aluminum ingot, pure zinc ingot, and Mg-Mn intermediate alloy.

Comparative example 2

The magnesium alloy of the comparative example had the following chemical components: gd 1.70 wt%, Zn 0.10 wt%, Zr 0.30 wt%, Sc 0.05 wt%, Ti 0.20 wt%, impurity element < 0.10%, and Mg for the rest, and the preparation method of the magnesium alloy of this comparative example was the same as that of example 1.

Comparative example 3

The magnesium alloy of the comparative example had the following chemical components: gd 2.20 wt%, Zn 0.25 wt%, Zr 0.70 wt%, Sc 0.3 wt%, Ti 0.25 wt%, impurity element < 0.10%, and Mg for the rest, and the preparation method of the magnesium alloy of this comparative example was the same as that of example 1.

Comparative example 4

The magnesium alloy of the comparative example had the following chemical components: gd 2.20 wt%, Zn 0.25 wt%, impurity element < 0.10%, and the balance Mg, and the preparation method of the magnesium alloy of this comparative example was the same as that of example 1.

Comparative example 5

The magnesium alloy of the comparative example had the following chemical components: gd 2.20 wt%, Zn 0.25 wt%, Zr 0.30 wt%, Ti 0.20 wt%, impurity elements < 0.10%, and the balance Mg, and the method of preparing the magnesium alloy of this comparative example was the same as in example 1.

Comparative example 6

The magnesium alloy of the comparative example had the following chemical components: gd 2.20 wt%, Zn 0.25 wt%, Sc 0.05 wt%, Ti 0.20 wt%, impurity element < 0.10%, and the balance Mg, and the method of preparing the magnesium alloy of this comparative example was the same as in example 1.

Comparative example 7

The composition of the magnesium alloy in this comparative example was the same as that of example 1 except that the ingot was not subjected to homogenization treatment in the preparation method of the magnesium alloy in this comparative example.

Mechanical property tests are carried out on the high-elongation wrought magnesium alloy of the embodiment and the magnesium alloy of the comparative example, the mechanical property test method is carried out according to GB T228.1-2010, and the mechanical property indexes of the magnesium alloy of the embodiment and the comparative example are shown in Table 1.

TABLE 1 mechanical Properties at room temperature of magnesium alloys

The mechanical property test results show that the tensile strength of the high-elongation wrought magnesium alloy is more than or equal to 240MPa, the yield strength is more than or equal to 140MPa, and the elongation is more than or equal to 25%. The high-elongation wrought magnesium alloy of the present application can obtain good mechanical properties by adopting a small extrusion ratio, the extrusion ratio of the high-elongation wrought magnesium alloy in example 10 is 60, and the mechanical properties of the high-elongation wrought magnesium alloy are better than those of the magnesium alloy with the extrusion ratio of 4 under the same other conditions and element contents.

The AZ31 magnesium alloy of comparative example 1 is an alloy containing Mg, Al, Zn and Mn, and compared with comparative example 1, the tensile strength, yield strength and elongation of the high-elongation deformation magnesium alloy of the invention are all obviously higher than those of AZ31 magnesium alloy.

The magnesium alloy composition of comparative example 2 is the same as the high-elongation wrought magnesium alloy composition of the present application, but the c/a ratio of the magnesium alloy cannot be effectively improved due to the low content of Gd and Zn, so that the elongation is significantly lower than that of the high-elongation wrought magnesium alloy of the present application, and the tensile strength and the yield strength are also reduced to different degrees.

The magnesium alloy composition of comparative example 3 is the same as the high elongation wrought magnesium alloy composition of the present application, but the contents of Zr, Sc, and Ti are higher than the content range of the high elongation wrought magnesium alloy of the present application, resulting in significant precipitation of a second phase, resulting in a decrease in elongation of the magnesium alloy.

The magnesium alloys of comparative examples 4, 5, and 6, in which other elements have the same composition as that of the high-elongation wrought magnesium alloy of the present application, but do not contain Zr, Sc, Ti, Sc, or Ti, have low grain refinement, poor material uniformity, and significantly lower elongation than that of the high-elongation wrought magnesium alloy of the present application.

The magnesium alloy in comparative example 7 has the same composition as the high elongation wrought magnesium alloy of the present application, but is prepared without homogenization treatment to segregate the alloy components, and has a lower elongation than the magnesium alloy of example 1 of the present application.

Under the same preparation process conditions, the alloy element composition selects Gd 2.0-2.20%, Zn 0.20-0.28%, Zr 0.20-0.50%, Sc 0.01-0.10%, Ti 0.05-0.20%, and the balance of Mg and impurity elements, so that the comprehensive mechanical property is better, and the preparation method is a preferred scheme; wherein, the element composition is selected from Gd 2.20%, Zn 0.25%, Zr 0.30%, Sc 0.05%, Ti 0.20%, and the balance of Mg and impurity elements, which is the most preferable scheme.

It should be understood that the above examples are only for clarity of illustration and are not intended to limit the embodiments. Other variations and modifications will be apparent to persons skilled in the art in light of the above description. And are neither required nor exhaustive of all embodiments. And obvious variations or modifications therefrom are within the scope of the invention.

Claims (2)

1. The high-elongation wrought magnesium alloy is characterized by comprising the following elements in percentage by mass: 2.20% of Gd, 0.25% of Zn, 0.30% of Zr, 0.05% of Sc, 0.20% of Ti, and the balance of Mg and impurity elements; the preparation method of the high-elongation wrought magnesium alloy comprises the following steps of:

s1, taking a pure magnesium ingot, a pure zinc ingot, an Mg-Gd intermediate alloy, an Mg-Zr intermediate alloy, an Mg-Sc intermediate alloy and a Zn-Ti intermediate alloy according to selected mass percentages;

s2, mixing the raw materials in the step S1 in CO₂And SF₆Heating at 730 deg.C in a protective atmosphere of mixed gas with a volume ratio of 200:1, smelting for 60min, stirring for 10min, refining for 20min, heating to 760 deg.C after refining, and standing for 40min to obtain a melt;

s3, casting the melt in the step S2 into a semi-continuous ingot at 700 ℃;

s4, homogenizing the cast ingot in the step S3, preserving heat for 24 hours at 400 ℃, then cooling by air cooling, cutting into blanks and peeling;

s5, placing the blank in the step S4 into an extruder, and extruding the blank into a bar under the conditions that the extrusion temperature is 350 ℃, the extrusion ratio is 8 and the extrusion speed is 10m/min to obtain the high-elongation deformation magnesium alloy.

2. The high elongation wrought magnesium alloy of claim 1, wherein: the mass percentage of the impurity elements is 0-0.12%.