JP6649665B2 - Magnesium alloy manufacturing method, rolled magnesium alloy material, and magnesium alloy compact - Google Patents

Description

The present invention, magnesium alloy manufacturing process, magnesium alloy rolled material, and a magnesium alloy formed body.

Magnesium is the lowest density (= 1.7 g / cm ³ ) among practical structural metal materials, has easy recyclability unique to metal materials, and has abundant resources. It is attracting attention as a material.

  For example, in the automobile industry, members such as a steering wheel, a cylinder head cover, and an oil pan as exemplified in Patent Literature 1 below are made of a magnesium alloy cast material. In addition, for example, in the case of home appliances, housings of home appliances such as personal computers and mobile phones are made of a magnesium alloy casting.

JP 2008-24113 A

  However, there are issues in the production method of magnesium alloy castings by casting, such as the need for post-processing to compensate for casting defects, low yield, and problems with the strength and rigidity of the members. I do. In order to solve these problems, it is useful to study alloying elements added to the magnesium alloy. In addition, the plastic working process generally has a high yield, and can achieve high strength and high toughness at the same time as forming. Therefore, it can be said that the plastic working process is an effective means for expanding demand for magnesium alloys.

The present invention has been made in view of the above-described problems, and an object of the present invention is to provide a magnesium alloy manufacturing method capable of obtaining a high-performance magnesium alloy rolled material that simultaneously achieves high strength and high ductility. It is in. The present invention also aims at providing a high strength and high ductility at the same time achieving to luma magnesium alloy rolled material, and a magnesium alloy formed body.

The method for producing a magnesium alloy according to the present invention comprises: 7.0 to 10 mass% of Al, 0 to 1.5 mass% of Zn, 0.3 to 3.2 mass% of Ca, and 0.01 to 0.3 mass% of Mn. Containing, the balance is magnesium alloy having incombustible properties consisting of magnesium and unavoidable impurities, characterized in that the equivalent circular diameter of the network of the intermetallic compound is formed using a cast material that has been refined to 200μm or less, wherein the equivalent circular diameter for the network to form the intermetallic compound, assumes a circular intermetallic compound is observed in a predetermined cross-section, the crystal grains size: the circular calculated from the equation a = π / 4 × D ² It is characterized in that rolling is performed at a total reduction of 75% or more when the sample temperature exceeds 400 ° C to 450 ° C or less and the roll temperature is 80 to 150 ° C. The purpose is to produce a rolled Mg alloy material having a thickness of 3 mm or more.

  Further, the magnesium alloy manufacturing method according to the present invention may further include a step of annealing at 150 to 275 ° C. after rolling.

  Furthermore, in the magnesium alloy manufacturing method according to the present invention, in a room temperature tensile test at a quasi-static strain rate, when a tensile test is performed in a direction parallel to the rolling direction, a tensile strength of 330 MPa or more and a fracture of 11% or more A rolled Mg alloy material having a thickness of 3 mm or more that exhibits elongation can be produced.

The rolled magnesium alloy material according to the present invention contains 7.0 to 10 mass% of Al, 0 to 1.5 mass% of Zn, 0.3 to 3.2 mass% of Ca, and 0.01 to 0.3 mass% of Mn. It is a rolled material containing magnesium and unavoidable impurities, the balance being magnesium and inevitable impurities, and having a thickness of 3 mm or more, and having a recrystallization rate of a matrix of 5% or more and a crystal grain size of a recrystallized portion of 10 μm or less. , and the less the average value of 2μm equivalent circular diameter to form a network of intermetallic compounds, the maximum value of Ri der less 10 [mu] m, the equivalent circular diameter of the network of the intermetallic compound is formed, observed in a given cross-section Assuming that the intermetallic compound to be formed is a circle, the crystal grain area is the diameter (D) of the circle calculated from the formula of A = π / 4 × D ^2. To the direction When subjected to tensile test in a direction parallel, and is characterized in that indicating the above tensile strength and 11% or more of elongation at break 330 MPa.

  The magnesium alloy compact according to the present invention is obtained by processing the above-mentioned rolled material into a predetermined form.

ADVANTAGE OF THE INVENTION According to this invention, the magnesium alloy manufacturing method which can obtain the high performance magnesium alloy rolled material which achieves high strength and high ductility simultaneously can be provided. Further, according to the present invention, it is possible to provide a high strength and high ductility at the same time achieving to luma magnesium alloy rolled material, and a magnesium alloy formed body.

It is a figure for demonstrating the network which an intermetallic compound forms, The divisional diagram (a) in FIG. 1 is a figure which shows the network which an intermetallic compound forms in the casting material outside this invention, and FIG. 1 is a diagram showing a network formed by the intermetallic compound of the present invention. The diagram (a-1) and the diagram (b-1) in FIG. 1 are schematic diagrams for explaining a network formed by an intermetallic compound, and the diagram (a-2) in FIG. And (b-2) are SEM observation photographs showing an intermetallic compound. 3A and 3B are SEM observation photographs and element analysis results of a magnesium alloy cast material according to the present embodiment cast using AZX811. In FIGS. 2A to 2D, Mn is 0. 2, and FIG. 2 shows the fractions (e) to (h) in FIG. 2 containing 0.156% of Mn and the fractions (i) to (f) in FIG. (L) contains 0.283% of Mn. It is a figure which shows the SEM observation photograph and elemental analysis result of the magnesium alloy casting material concerning the comparative example cast using AZX811 containing 1.180% of Mn. It is a micro observation photograph of the magnesium alloy rolled material which concerns on this embodiment, The division | segmentation (a) in FIG. 4 and the division | segmentation (d) were produced using AZX810.3, Separation diagrams (b) and (e) were made using AZX811, and division diagrams (c) and (f) in FIG. 4 were made using AZX813. is there. 5 is an SEM observation photograph showing the magnesium alloy cast material and the magnesium alloy rolled material according to the present embodiment, and FIG. 5A is a SEM observation photograph of the magnesium alloy cast material according to the present embodiment; FIG. 5 (b) is a SEM observation photograph of a rolled magnesium alloy material manufactured using AZX810.3, and FIG. 5 (c) is a magnesium diagram manufactured using AZX811. FIG. 5 is a SEM observation photograph of a rolled alloy material, and FIG. 5D is a SEM observation photograph of a rolled magnesium alloy material produced using AZX813. It is a figure which shows the SEM observation photograph of the magnesium alloy rolled material which concerns on this embodiment produced using AZX810.5, and the subdivisions (a) to (e) of FIG. This is an observation of a visual field at an arbitrary location. It is a figure which shows the SEM observation photograph of the magnesium alloy rolled material which concerns on this embodiment produced using AZX811, and the subdivisions (a) to (e) in FIG. This is an observation of the field of view. It is a figure which shows the SEM observation photograph of the magnesium alloy rolled material which concerns on this embodiment produced using AZX812, and the subdivided figures (a) to (e) in FIG. This is an observation of the field of view.

  Hereinafter, a preferred embodiment for carrying out the present invention will be described with reference to the drawings. It should be noted that the following embodiments do not limit the invention according to each claim, and not all combinations of the features described in the embodiments are necessarily essential for solving the invention. .

  The inventors have conducted intensive studies to solve the above-described problems, and as a result, by performing rolling under predetermined conditions on a magnesium alloy cast material having a predetermined alloy composition and alloy structure, high strength and high strength are obtained. It has been found that a rolled magnesium alloy material that simultaneously achieves ductility can be obtained. Therefore, in the embodiments described below, analysis results and test results showing the characteristics of the magnesium alloy manufacturing method found by the inventors and the magnesium alloy cast material, magnesium alloy rolled material, and magnesium alloy molded body manufactured by the manufacturing method. Will be described. Here, FIG. 1 is a diagram for explaining a network formed by an intermetallic compound, and FIG. 1 (a) is a diagram showing a network formed by an intermetallic compound found in a casting material outside the present invention. FIG. 1B is a diagram showing a network formed by the intermetallic compound of the present invention. The diagram (a-1) and the diagram (b-1) in FIG. 1 are schematic diagrams for explaining a network formed by an intermetallic compound, and the diagram (a-2) in FIG. And (b-2) are SEM observation photographs showing an intermetallic compound. The SEM observation photograph of FIG. 1 was obtained using a scanning electron microscope (SEM; JCM-6000, manufactured by JEOL Ltd.).

  The magnesium alloy used in the magnesium alloy manufacturing method according to the present embodiment includes 7.0 to 10 mass% of Al, 0 to 1.5 mass% of Zn, 0.3 to 3.2 mass% of Ca, and 0.01 to 0 mass%. It contains 0.3 mass% of Mn, and the balance has a component composition consisting of magnesium and unavoidable impurities.

Aluminum (Al) is preferably added in a range of 7.0 to 10% in order to precipitate a precipitate with calcium (Al ₂ Ca) inside the magnesium alloy. If the addition amount of aluminum exceeds 10%, excessive precipitates precipitate and workability is reduced. On the other hand, if the addition amount of aluminum is less than 7.0%, it is not possible to expect sufficient precipitation of precipitates, and it is difficult to obtain a desired strength.

  Zinc (Zn) may be added within a range of 0 to 1.5%. Zinc contributes to improvement of mechanical properties such as castability and strength. However, when the amount of zinc exceeds 1.5%, castability decreases.

  Calcium (Ca) is preferably added in the range of 0.4 to 3.2% in order to provide the magnesium alloy with flame retardancy.

  Manganese (Mn) is preferably added in the range of 0.01 to 0.3%. By adding manganese within this range, the effect of iron, which is an impurity element that lowers corrosion resistance, can be reduced.

  In the method for manufacturing a magnesium alloy according to the present embodiment, a magnesium alloy having the above-described component composition is cast to obtain a magnesium alloy casting. Here, although not particularly limited, the magnesium alloy casting material according to the present embodiment is prepared by weighing AM60B base metal and Mg-30% Ca mother alloy so as to have a desired composition, and dissolving in a steel crucible in an Ar gas atmosphere. Then, after bubbling using Ar gas is performed, the temperature of the molten metal can be adjusted to the temperature of the molten metal during the calming of the molten metal to produce the molten metal. Then, although not particularly limited, slag of the molten metal was removed before casting, and antigravity casting was performed. Antigravity casting is a method in which a steel mold is directly immersed in a molten metal and cast using a pressure difference with a vacuum pump connected to the mold. The method for manufacturing a magnesium alloy according to the present embodiment is not limited to the above-described method. As will be described later, as long as the equivalent circular diameter formed by the network of the intermetallic compound is reduced to 200 μm or less, A casting method may be used.

In the magnesium alloy casting according to the present embodiment, the equivalent circular diameter formed by the network of the intermetallic compound is reduced to 200 μm or less. Here, the equivalent circular diameter to form a network of intermetallic compounds, the intermetallic compound assuming circular, grain size: the diameter calculated from the equation ^{A = π / 4 × D 2} (D). In the present embodiment, the rolling process described later can be easily performed by using a magnesium alloy casting material in which the equivalent circular diameter formed by the network of the intermetallic compound is reduced to 200 μm or less.

  As shown in FIG. 1A, the network of the intermetallic compound found in the casting material outside the present invention is formed continuously at the grain boundaries and becomes coarse grains. On the other hand, as illustrated in FIG. 1B, the network of the intermetallic compound according to the present invention is discontinuously formed at the grain boundaries and becomes fine grains. Although not limited to such a formation structure, in the method for manufacturing a magnesium alloy according to the present embodiment, it is preferable to use a magnesium alloy casting material in which an intermetallic compound is finely dispersed. In addition, in the SEM observation photographs of the distribution diagram (a-2) and the distribution diagram (b-2) in FIG. 1, the white and gray portions indicate intermetallic compounds.

  Next, in the magnesium alloy manufacturing method according to the present embodiment, a rolling process is performed on the magnesium alloy cast material according to the above-described embodiment. A general rolling mill can be used for the rolling process according to the present embodiment. The sample temperature during the rolling process of the magnesium alloy cast material is preferably set to a temperature exceeding 400 ° C. to 450 ° C. or less. Further, the roll temperature of the roll of the rolling mill is preferably in the range of 80 to 150 ° C. Further, it is preferable to perform rolling so that the total reduction is 75% or more, for example, at a reduction of 15 to 25% per pass. By setting the total rolling reduction to 75% or more, the alloy structure of the rolled magnesium alloy material is refined.

  In the present embodiment, after the rolling process is performed on the magnesium alloy cast material, annealing can be performed at 150 to 275 ° C. By performing the annealing after the rolling process, the elongation at break of the rolled magnesium alloy material can be increased.

  In the method of manufacturing a magnesium alloy according to the present embodiment, a magnesium alloy cast material having a thickness of 3 mm or more, which exhibits a tensile strength of 330 MPa or more and an elongation at break of 11% or more, by subjecting a magnesium alloy cast material to rolling under the above rolling conditions. Wood is obtained. Therefore, according to the method for manufacturing a magnesium alloy according to the present embodiment, it is possible to provide a high-performance magnesium alloy rolled material that simultaneously achieves high strength and high ductility.

  The method for manufacturing a magnesium alloy according to the present embodiment has been described above. Next, an analysis result and a test result showing characteristics of the magnesium alloy cast material manufactured by the magnesium alloy manufacturing method according to the present embodiment will be described.

  The present inventors observe the structure of the magnesium alloy casting obtained by the above-described magnesium alloy production method using an optical microscope and a scanning electron microscope (SEM; manufactured by JEOL Ltd., JCM-6000). Composition analysis was performed by image analysis using EDS (Energy Dispersive X-ray Spectrometry) attached to a scanning electron microscope and analysis software (Sigma Scan Pro5, manufactured by Hulinks Co., Ltd.). The equivalent circular diameter formed by the network of the intermetallic compound was calculated by the same method as described above. Specifically, it was read from the secondary electron image shown in FIGS. Here, FIG. 2 is a diagram showing a SEM observation photograph and a result of elemental analysis of the magnesium alloy cast material according to the present embodiment cast using AZX811. d) contains 0.016% of Mn, and the fractions (e) to (h) in FIG. 2 contain 0.156% of Mn, and the fractions in FIG. Figures (i) to (l) contain 0.283% Mn. FIG. 3 is a view showing an SEM observation photograph and an elemental analysis result of a magnesium alloy cast material according to a comparative example cast using AZX811 containing 1.180% of Mn. Here, the nomenclature of the alloy name is such that “A” represents “Al”, “Z” represents “Zn”, “X” represents “Ca”, and “M” represents “Mn”. Represent. The numbers following the alphabets indicate the approximate addition concentration (mass%) of each element. For example, the approximate concentration of the added element of AZX811 according to Example 1 is Mg-8 mass% Al-1 mass% Zn-1 mass% Ca.

  The magnesium alloy casting according to the present embodiment using AZX811 containing 0.016% Mn shown in FIG. 2 (a) had an equivalent circular diameter of 160 μm formed by the network of the intermetallic compound. . The magnesium alloy casting according to the present embodiment using AZX811 containing 0.156% of Mn shown in FIG. 2 (e) has an equivalent circular diameter of 160 μm formed by an intermetallic compound network. there were. Furthermore, the magnesium alloy casting according to the present embodiment using AZX811 containing 0.283% of Mn shown in FIG. 2 (i) has an equivalent circular diameter of 160 μm formed by a network of intermetallic compounds. there were. On the other hand, in the magnesium alloy casting according to the comparative example using AZX811 containing 1.180% Mn shown in FIG. 3A, the equivalent circular diameter formed by the network of the intermetallic compound was 156 μm. Was. From the above, it was confirmed that the magnesium alloy casting according to the present embodiment had a finer intermetallic compound. As described above, the rolling process can be easily performed by using a magnesium alloy cast material in which the equivalent circular diameter formed by the network of the intermetallic compound is reduced to 200 μm or less.

  Further, as shown in FIG. 2, it is found that the main components of the intermetallic compound forming the network of the magnesium alloy casting according to the present embodiment are Al and Ca. On the other hand, as shown in FIG. 3, it can be seen that the main components of the intermetallic compound forming the network of the magnesium alloy casting according to the comparative example are Al, Ca and Mn.

  The magnesium alloy casting according to the present embodiment has been described above. Next, analysis results and test results showing characteristics of the rolled magnesium alloy material manufactured by the magnesium alloy manufacturing method according to the present embodiment will be described. Here, FIG. 4 is a micro-observation photograph of the magnesium alloy rolled material according to the present embodiment, and the sub-diagrams (a) and (d) in FIG. 4 are produced using AZX810.3. 4A and 4B, and the diagram (b) and the diagram (e) in FIG. 4 are made using AZX811. The diagram (c) and the diagram (f) in FIG. It was produced using FIG. 5 is an SEM observation photograph showing the magnesium alloy cast material and the magnesium alloy rolled material according to the present embodiment, and FIG. 5 (a) shows the divided view (a) of the magnesium alloy cast material according to the present embodiment. FIG. 5B is an SEM observation photograph, and FIG. 5B is a SEM observation photograph of a rolled magnesium alloy material produced using AZX810.3, and FIG. 5C is a AZX811. FIG. 5 is a SEM observation photograph of a rolled magnesium alloy material manufactured using the method, and FIG. 5D is a SEM observation photograph of a rolled magnesium alloy material manufactured using AZX813.

  As shown in FIG. 4, it was confirmed that the rolled magnesium alloy material according to the present embodiment had a structure in which the crystal grains of the intermetallic compound were refined to 10 μm or less. In addition, it turned out that the magnesium alloy rolled material which concerns on this embodiment has a bimodal structure which has two peaks in distribution of a crystal grain size.

  Further, as shown in FIG. 5 (b) to FIG. 5 (d), the magnesium alloy rolled material according to the present embodiment relates to the present embodiment shown in FIG. 5 (a). It has been found that by performing a rolling process on a magnesium alloy cast material, an intermetallic compound which was in the form of a block or a plate at the time of casting becomes a needle, a fine grain, or a fine plate.

Next, the alloy composition and the rolling of the magnesium alloy rolled materials according to Examples 1 to 13 and Comparative Examples 1 to 3 of the magnesium alloy rolled material according to the present embodiment manufactured by changing the alloy composition and the rolling conditions. Table 1 shows the conditions. Table 2 shows the measurement results of the mechanical properties of the magnesium alloy rolled materials according to Examples 1 to 13 and Comparative Examples 1 to 3 of the magnesium alloy rolled material according to the present embodiment. Here, the measurement of the tensile strength of the rolled magnesium alloy material was a room temperature tensile test based on a quasi-static strain rate according to JIS Z2241 metal material tensile test method, and the test was performed in a direction parallel to the rolling direction. More specifically, in the tensile test, a magnesium alloy rolled material was prepared in parallel with the rolling direction to prepare a cylindrical test piece having a diameter of 12 mm and a height of 20 mm, and the initial strain rate was 1. The ^measurement was performed at 1 × 10 ⁻³ s ⁻¹ . The measurement of the elongation at break and the yield strength of the rolled magnesium alloy material was performed based on the JIS Z2241 tensile test method for metallic materials. In Tables 1 and 3, alloys having the same alloy name but different alloy compositions are due to different lots.

  As can be seen from Table 2, the rolled magnesium alloy material according to the present embodiment exhibited a tensile strength of 330 MPa or more, which is the target value of the present invention, and a breaking elongation of 11% or more. On the other hand, the rolled magnesium alloy material according to the comparative example could not simultaneously satisfy the tensile strength of 330 MPa or more and the elongation at break of 11% or more, which are the target values of the present invention. Therefore, it was confirmed that according to the magnesium alloy production method according to the present embodiment, it is possible to obtain a magnesium alloy rolled material that achieves both high strength and high ductility at the same time.

  Further, after performing rolling processing on the magnesium alloy cast material according to the present embodiment, the alloy composition of the magnesium alloy rolled material according to the present embodiment and the magnesium alloy rolled material according to the comparative example subjected to annealing under predetermined conditions, and rolling. Table 3 shows the conditions and annealing conditions. Furthermore, after rolling the magnesium alloy cast material under the above-mentioned rolling conditions, the measurement results of the mechanical properties of the magnesium alloy rolled material annealed under predetermined conditions and the mechanical properties of the magnesium alloy rolled material according to the comparative example Table 4 shows the measurement results of the properties.

  As can be seen from Table 4, after the magnesium alloy cast material was subjected to the rolling process under the above-described rolling conditions, and then annealed under the above-described conditions, the magnesium alloy rolled material according to the present embodiment had a tensile strength of 330 MPa or more and 11 MPa. % At the same time. On the other hand, the rolled magnesium alloy material according to the comparative example could not simultaneously satisfy the tensile strength of 330 MPa or more and the elongation at break of 11% or more. Therefore, according to the method for manufacturing a magnesium alloy according to the present embodiment, when the magnesium alloy cast material is subjected to rolling under the above-described rolling conditions, and then annealed under predetermined conditions, the same as in the above-described case. A magnesium alloy rolled material that achieves both strength and high ductility at the same time is obtained.

  Next, the present inventors, in order to investigate further features of the alloy structure of a magnesium alloy rolled material that simultaneously achieves high strength and high ductility, the magnesium alloy rolled material according to the present embodiment and the magnesium alloy according to the comparative example The recrystallized grain size and recrystallization rate of the rolled material were measured and calculated. Table 5 shows the results. Here, the particle size of the recrystallized particle size was obtained by using the intercept method.

  As can be seen from Table 5, in the rolled magnesium alloy material according to the present embodiment, the crystal grain size of the recrystallized portion is 10 μm or less, and the recrystallization rate of the parent phase is 5% or more. Further, from the results in Table 5, the crystal grain size of the recrystallized portion of the rolled magnesium alloy material according to the present embodiment is smaller than the crystal grain size of the recrystallized portion of the rolled magnesium alloy material according to the comparative example. It can be said that there is a tendency.

  Further, the equivalent circular diameter formed by the network of the intermetallic compound crystallized in the rolled magnesium alloy material according to the present embodiment was calculated by the same method as described above with reference to FIGS. Here, FIG. 6 is a view showing a SEM observation photograph of the rolled magnesium alloy material according to the present embodiment manufactured using AZX810.5, and FIG. Is an observation of a visual field of an arbitrary portion of a rolled magnesium alloy material. FIG. 7 is a view showing a SEM observation photograph of the rolled magnesium alloy material according to the present embodiment manufactured using AZX811. FIG. 7 (a) to FIG. This is an observation of a visual field at an arbitrary position of a rolled alloy material. Further, FIG. 8 is a diagram showing SEM observation photographs of the rolled magnesium alloy material according to the present embodiment manufactured using AZX812, and FIG. This is an observation of a visual field at an arbitrary position of a rolled alloy material.

  As shown in FIG. 6, the equivalent circular diameter formed by the network of the intermetallic compound of the magnesium alloy rolled material according to the present embodiment using AZX810.5 has a maximum value of 9.9 μm and an average value of 2 μm. there were. As shown in FIG. 7, the equivalent circular diameter formed by the network of the intermetallic compound of the magnesium alloy rolled material according to the present embodiment using AZX811 is a maximum value of 7.8 μm, and the average value is 1. It was 6 μm. Further, as shown in FIG. 8, the equivalent circular diameter formed by the network of the intermetallic compound of the magnesium alloy rolled material according to the present embodiment using AZX812 has a maximum value of 3.2 μm and an average value of 1 μm. 0.3 μm.

  Therefore, according to the magnesium alloy manufacturing method according to the present embodiment, by performing a rolling process on a magnesium alloy cast material whose equivalent circular diameter formed by a network of intermetallic compounds is reduced to 200 μm or less, The average value of the equivalent circular diameter formed by the compound network was 2 μm or less, and the maximum value was 10 μm or less, indicating that the intermetallic compound was finely dispersed.

From the above analysis and test results, in the magnesium alloy rolled material according to the present embodiment, the precipitate (Al ₂ Ca) precipitated inside the magnesium alloy, which was conventionally considered unnecessary, improves the mechanical properties. It has been clarified that it functions as a reinforcing material and that the strength is improved by the particle dispersion and the refinement of crystal grains.

  The rolled magnesium alloy material according to the present embodiment can be processed into a predetermined form to form a magnesium alloy compact.

Claims (5)

It contains 7.0 to 10 mass% of Al, 0 to 1.5 mass% of Zn, 0.3 to 3.2 mass% of Ca, and 0.01 to 0.3 mass% of Mn, with the balance being magnesium and inevitable impurities. comprising the Mg alloy having flame retardant properties, equivalent to equivalent circular diameter to form a network of intermetallic compound is characterized by using a cast material that is miniaturized to 200μm or less, the network of the intermetallic compound forms the circle diameter, the intermetallic compound is observed in a predetermined cross-section assumes a circular, grain size: a a = π / 4 × the circular diameter calculated from the equation D ² (D), sample temperature A rolled Mg alloy material having a thickness of 3 mm or more, characterized in that rolling is performed at a total draft of 75% or more in a temperature range from a temperature exceeding 400 ° C to 450 ° C or less and a roll temperature in a range of 80 to 150 ° C. For producing magnesium alloy.   A magnesium alloy production method for producing a rolled Mg alloy material having a thickness of 3 mm or more, characterized in that the magnesium alloy is produced by the method according to claim 1 and that annealing is performed at 150 to 275 ° C. after rolling. .   It is characterized by being produced by the method according to claim 1 or claim 2, and in a room temperature tensile test by a quasi-static strain rate, when a tensile test is performed in a direction parallel to a rolling direction, 330 MPa or more. A method for producing a magnesium alloy, which comprises producing a rolled Mg alloy material having a thickness of 3 mm or more and exhibiting a tensile strength and a breaking elongation of 11% or more. It contains 7.0 to 10 mass% of Al, 0 to 1.5 mass% of Zn, 0.3 to 3.2 mass% of Ca, and 0.01 to 0.3 mass% of Mn, with the balance being magnesium and inevitable impurities. It is a rolled material having a thickness of 3 mm or more and having flame retardancy, a recrystallization rate of a matrix of 5% or more, a crystal grain size of a recrystallized portion of 10 μm or less, and a network of an intermetallic compound. to the average value of equivalent circle diameter of 2μm or less, the maximum value of Ri der less 10 [mu] m, the equivalent circular diameter of the network of the intermetallic compound is formed, assuming a circular intermetallic compound is observed in a predetermined cross-section The crystal grain area is the diameter (D) of the circular shape calculated from the formula of A = π / 4 × D ^{2. In} a room temperature tensile test at a quasi-static strain rate, a tensile test is performed in a direction parallel to the rolling direction. When I went, 3 Magnesium alloy rolled material, characterized in that indicating the above tensile strength and 11% or more elongation at break 0 MPa. A magnesium alloy compact formed by using the rolled material according to claim 4 .