JP4332889B2 - Method for producing magnesium-based alloy compact - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method for producing a molded body made of a magnesium-based alloy by plastic working. In particular, the present invention relates to a method for producing a magnesium-based alloy compact having a high productivity by lowering the processing temperature during plastic processing.
[0002]
[Prior art]
Magnesium-based alloys are lighter than aluminum and have a higher specific strength and specific rigidity than steel and aluminum, and are widely used in the body of various electrical products as well as aircraft parts and automobile parts.
[0003]
However, since Mg and its alloys have a close-packed hexagonal lattice (hcp) structure, they have poor ductility and extremely poor plastic workability, but magnesium-based alloys have good workability by raising the temperature during processing. It is widely known that For example, Patent Documents 1 and 2 describe a technique for threading a magnesium-based alloy material to a temperature state in which a superplastic phenomenon appears.
[0004]
[Patent Document 1]
JP 2000-283134 A
[Patent Document 2]
JP 2000-343178 A
[0005]
[Problems to be solved by the invention]
However, when plastically processing a magnesium-based alloy material, the temperature at which the superplastic phenomenon occurs is a high temperature of 250 ° C. or higher, so that the conventional method cannot produce a molded body by plastic processing with high productivity. There is.
[0006]
Conventionally, when strong processing such as plastic processing is performed to obtain a compact made of a magnesium-based alloy, the extruded material or rolled material of the magnesium-based alloy, which is a workpiece, is generally raised to 250 ° C. or more, depending on the degree of processing. It is necessary to heat and process. Therefore, not only the heating equipment for high temperature such as 250 ° C. or more is required, but also the processing materials such as molds and rolls used for plastic working are exposed to high temperature, thereby shortening the life and increasing the cost. Invite. Therefore, heating above 250 ° C. is never preferable in industrial production.
[0007]
Then, the main objective of this invention is to provide the manufacturing method of the magnesium base alloy molded object which can manufacture the plastic-working molded object which consists of magnesium base alloys with sufficient productivity.
[0008]
[Means for Solving the Problems]
As a result of various investigations in a magnesium-based alloy that is usually difficult to perform a strong work such as plastic working, the present inventors have used a magnesium-based alloy material that has been subjected to a specific drawing process in advance. Even so, it has been found that plastic working is possible, and the present invention has been completed.
[0009]
That is, the manufacturing method of the magnesium-based alloy formed body of the present invention was obtained by drawing. An average crystal grain size of 10 μm or less A linear body made of a magnesium-based alloy is plastically processed into a molded body at a processing temperature of less than 250 ° C.
[0010]
Conventionally, when a magnesium-based alloy material is plastically processed to obtain a compact, an extruded material or a rolled material has been used as a workpiece. However, in the case of an extruded material or a rolled material, when plastic processing is performed, it must be heated to 250 ° C. or higher, and a reduction in processing temperature has been strongly desired. Therefore, the present invention achieves a reduction in processing temperature, that is, plastic processing at less than 250 ° C., particularly 200 ° C. or less, by using a linear body obtained by drawing rather than an extruded material or a rolled material. . As described above, in the present invention, by using the drawn wire, the processing temperature at the time of plastic processing can be made less than 250 ° C., and a conventional high-temperature heating means is unnecessary. In addition, the life of workpieces such as molds and rolls used for plastic working can be extended, and productivity can be improved. Hereinafter, the present invention will be described in more detail.
[0011]
In the present invention, examples of the linear body made of a magnesium-based alloy include a wire (linear body), a rod-shaped body, and a pipe. The cross section may be circular or non-circular such as a rectangle or an ellipse, that is, an irregular shape.
[0012]
In the present invention, for example, in the case of obtaining a wire or a rod-like body, the drawing rate is 1 ° C./sec to 100 ° C./sec, the processing temperature is 50 ° C. or more and 200 ° C. or less (more preferably 150 ° C.). In the following, the degree of processing: 10% or more with respect to one drawing process (one pass), and drawing the extruded material or rolled material at a linear speed of 1 m / sec or more. For example, when obtaining a pipe, the drawing temperature: 50 ° C. or more and 300 ° C. or less (more preferably 100 ° C. or more and 200 ° C. or less, more preferably 100 ° C. or more and 150 ° C. or less), the degree of processing: 5% for one drawing process Above (more preferably 10% or more, particularly preferably 20% or more), the temperature rise rate to the drawing temperature: 1 ° C./sec to 100 ° C./sec, the drawing rate: 1 m / sec or more, the extruded material or the rolled material is drawn. Can be mentioned. By performing such a specific drawing process, the alloy structure can be refined, specifically, the average crystal grain size can be 10 μm or less. And this invention is the above-mentioned alloy Organization By miniaturization, plastic workability can be improved even when the heating temperature is less than 250 ° C., and a desired molded body can be obtained. Also, after the drawing process, the obtained striatum The You may heat to the temperature of 100 to 300 degreeC, More preferably, it is 150 to 300 degreeC. This heat annealing is effective for recovery of strain introduced by drawing and further refinement of crystal grains by promoting recrystallization. The holding time of this heating temperature is preferably about 5 to 20 minutes.
[0013]
In the present invention, examples of the plastic working include forging, swaging, and bending. When forging is performed as plastic processing, the following temperature conditions are suitable. That is, the reduction rate is expressed as r. ₁ %, When the processing temperature is T ° C., T is 3r ₁ +150> T ≧ 3r ₁ +10 (however, 20% ≦ r ₁ <80%, T <250 ° C.). For example, reduction ratio r ₁ In the case of = 20 (%), the heating temperature T (° C.) can be less than 250 ° C., particularly 70 ° C. or more and less than 210 ° C. When extruding or rolling material that has not been drawn is subjected to forging with a reduction ratio of 20%, cracking and the like cannot occur unless it is heated to a high temperature of 210 ° C. or higher. When the temperature is raised as described above, the life of the workpiece such as a mold or a roll is shortened. On the other hand, in the present invention, by using the drawn material, the heating temperature at the time of forging with a rolling reduction of 20% can be set to less than 210 ° C. due to the fine effect of the alloy structure. The life of the processed material can be made longer. Reduction ratio r ₁ Is less than 33%, the lower limit of the heating temperature is 3r above. ₁ The upper limit of the heating temperature is set to less than 250 ° C. in consideration of the service life of a mold or a roll. Therefore, in the present invention, when plastic working with a rolling reduction exceeding 40%, which is industrially effective processing, can be performed sufficiently even if the processing temperature is less than 250 ° C. In strong processing with a rolling reduction of 80% or more, heating at 250 ° C. or higher is desired.
[0014]
When performing swaging as plastic working, the following temperature conditions are suitable. That is, the cross-sectional reduction rate is set to r ₂ %, When the processing temperature is T ° C., T is 3r ₂ +150> T ≧ 3r ₂ -30 (however, 20% ≦ r ₂ ≦ 80%, T <250 ° C.). For example, the cross-sectional reduction rate r ₂ In the case of 20%, the heating temperature T (° C.) can be less than 250 ° C., particularly 30 ° C. or more and less than 210 ° C. Therefore, when the cross-section reduction rate is 20%, the alloy structure is fine compared to the conventional method that requires heating at 210 ° C. or higher, using an extruded material or a rolled material that has not been drawn. The present invention using a drawing material can further extend the life of a workpiece such as a mold. Section reduction rate r ₂ Is over 33%, the lower limit of the heating temperature is 3r above. ₂ The upper limit of the heating temperature is set to less than 250 ° C. in consideration of the life of the mold and the like. In the present invention using a drawn material having a fine alloy structure, swaging can be performed at a processing temperature of less than 250 ° C. in processing with an area reduction ratio exceeding 40%, which is industrially effective processing. In strong processing where the cross-sectional reduction rate exceeds 80%, heating at 250 ° C or higher is desired.
[0015]
The following temperature conditions are suitable when bending as plastic working. That is, when the thickness of the linear body during bending is t mm, the bending radius is R mm, and the processing temperature is T ° C., when T is (1) 0.1 ≦ R / t ≦ 1.0, 250 > T ≧ 250−250 R / t, (2) When 1.0 <R / t ≦ 1.9, 500−250 R / t ≧ T> 0, (3) 1.9 <R / t ≦ 2.0 In this case, it is assumed that 25 ≧ T> 0. For example, when the ratio R / t between the bending radius R and the thickness t of the striate is 1.0 to 1.9, the heating temperature T (° C.) is less than 250 ° C., and particularly the upper limit is 500-250 R / t. It can be as follows. That is, as can be seen from the test results described later, the temperature can be set to less than 100 ° C. and further to about room temperature (for example, 20 ° C.). Moreover, when R / t is 1.9-2.0, heating temperature T (degreeC) can be 25 degrees C or less. In a conventional method using an extruded material or a rolled material that has not been subjected to drawing, a bending process with an R / t of 1.0 to 2.0, particularly a bending process of about 1.5 to 1.0 is performed. , Heating is required. On the other hand, according to the present invention, by using the drawing material, due to the effect of fine crystal grains, the bending process with a R / t of 1.0 to 2.0 is sufficiently performed without heating. It is possible to eliminate the need for heating equipment. Further, by not performing heating, it is possible to extend the life of a workpiece such as a mold. On the other hand, in the case of strong processing with R / t of less than 1.0, the lower limit of the heating temperature is the value determined by the above 250-250 R / t, and the upper limit of the heating temperature is in consideration of the life of the mold, The temperature is less than 250 ° C. In the conventional method using an extruded material, heating at 200 ° C. or higher is necessary for strong processing with R / t of 1.2 or less, and in particular, 250 ° C. with strong processing with R / t of 1.0 or less. The above heating is necessary. On the other hand, in the present invention, by using a drawing material having a fine alloy structure, even if the R / t is strong processing such as 0.1 to 1.0, the processing temperature is sufficiently less than 250 ° C. Processing can be performed.
[0016]
The thickness of the striated body is, for example, when the striated body is a wire (linear body) or a rod-shaped body and the cross-sectional shape is circular: the diameter, the striated body is a wire or rod-shaped body, and the cross-sectional shape is rectangular. In the case of shape: thickness, in the case where the filament is a pipe: the difference between the outer diameter and the inner diameter can be mentioned.
[0017]
In addition, when R / t is over 2.0, the degree of bending is low, and even extruded materials and rolled materials can be processed at normal temperature. Further, in strong working with R / t of less than 0.1, heating above 225 ° C. is desired. Therefore, in the present invention, it is not specified in consideration of the life of a workpiece such as a mold.
[0018]
The present invention , Go Regardless of the gold composition, it is effective in a magnesium-based alloy having an hcp structure with poor workability at about room temperature (for example, 20 ° C.). For example, a magnesium base alloy for casting or a magnesium base alloy for drawing can be used. Specifically, Al is 0.1 mass% 12 or more mass% What is contained below, Zn: 0.1 mass% 10 or more mass% The following and Zr: 0.1 mass% 2.0 mass% The thing containing is mentioned. When Al is contained, Mn: 0.1 mass% 2.0 mass% Hereinafter, Zn: 0.1 mass% More than 5.0 mass% Hereinafter, Si: 0.1 mass% More than 5.0 mass% What contains 1 or more types selected from the following is mentioned. As the alloy composition, AST, AS, AM, ZK and the like in typical ASTM symbols can be used. As the content of Al, mass% It may be distinguished between less than 0.1 to 2.0% and more than 2.0 to 12.0%. In general, it is used as an alloy containing Mg and impurities in addition to the above chemical components. Impurities include Fe, Si, Cu, Ni, Ca and the like.
[0019]
In the AZ system, the Al content is 2.0 to 12.0. mass% For example, AZ31, AZ61, AZ91, and the like can be given. AZ31 is, for example, mass% Al: 2.5-3.5%, Zn: 0.5-1.5%, Mn: 0.15-0.5%, Cu: 0.05% or less, Si: 0.1% or less, Ca: Magnesium-based alloy containing 0.04% or less. AZ61 is, for example, mass% Al: 5.5 to 7.2%, Zn: 0.4 to 1.5%, Mn: 0.15 to 0.35%, Ni: 0.05% or less, Si: 0.1% or less It is a magnesium-based alloy containing. AZ91 is for example mass% Al: 8.1 to 9.7%, Zn: 0.35 to 1.0%, Mn: 0.13% or more, Cu: 0.1% or less, Ni: 0.03% or less, Si: 0 A magnesium-based alloy containing up to 5%. In the AZ system, the Al content is 0.1 to 2.0. mass% As what becomes less than AZ10, AZ21 etc. are mentioned, for example. AZ10 is, for example, mass% Al: 1.0 to 1.5%, Zn: 0.2 to 0.6%, Mn: 0.2% or more, Cu: 0.1% or less, Si: 0.1% or less, Ca: 0 A magnesium-based alloy containing up to 4%. AZ21 is, for example, mass% Al: 1.4-2.6%, Zn: 0.5-1.5%, Mn: 0.15-0.35%, Ni: 0.03% or less, Si: 0.1% or less It is a magnesium-based alloy containing.
[0020]
In the AS system, the Al content is 2.0 to 12.0. mass% For example, AS41 and the like can be cited. AS41, for example, mass% Al: 3.7 to 4.8%, Zn: 0.1% or less, Cu: 0.15% or less, Mn: 0.35 to 0.60%, Ni: 0.001% or less, Si: 0 A magnesium-based alloy containing 6 to 1.4%. In the AS system, the Al content is 0.1 to 2.0. mass% AS21 etc. are mentioned as what becomes less than. AS21 is, for example, mass% Al: 1.4 to 2.6%, Zn: 0.1% or less, Cu: 0.15% or less, Mn: 0.35 to 0.60%, Ni: 0.001%, Si: 0.00. A magnesium-based alloy containing 6 to 1.4%.
[0021]
Examples of AM systems include AM60 and AM100. AM60 is, for example, mass% Al: 5.5 to 6.5%, Zn: 0.22% or less, Cu: 0.35% or less, Mn: 0.13% or more, Ni: 0.03% or less, Si: 0.5% A magnesium-based alloy containing: AM100 is, for example, mass% Al: 9.3 to 10.7%, Zn: 0.3% or less, Cu: 0.1% or less, Mn: 0.1 to 0.35%, Ni: 0.01% or less, Si: 0 A magnesium-based alloy containing 3% or less.
[0022]
In the ZK system, for example, ZK40, ZK60 and the like can be mentioned. ZK40 is, for example, mass% Zn: 3.5-4.5%, Zr: 0.45% or more magnesium-based alloy. ZK60 is, for example, mass% Zn: 4.8 to 6.2%, Zr: a magnesium-based alloy containing 0.45% or more.
[0023]
Although it is difficult to obtain sufficient strength with magnesium alone, preferable strength can be obtained by including the above chemical components.
[0024]
INDUSTRIAL APPLICABILITY The present invention can be applied to the manufacture of a molded body obtained by plastic processing of a linear body, for example, a reinforcing frame such as a spectacle frame or a portable electronic device, and a screw.
[0025]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below.
[0026]
Example 1
mass% And an extruded material (φ4.0 mm, including magnesium-based alloy (ASTM symbol AZ31 equivalent material) containing Al: 3.0%, Zn: 1.0%, Mn: 0.15%, the balance being Mg and impurities. φ3.0 mm) was prepared. The extruded material of φ4.0 mm was drawn to φ3.0 mm at a temperature of about 160 ° C. and a cross-section reduction rate per pass: 20% or less (temperature increase rate to 160 ° C .: about 10 (C / sec, linear velocity: 16 m / sec). Further, after the drawing process, a heat treatment was performed at 350 ° C. for 15 minutes to remove strain during the drawing process and to make the structure uniform and fine by recrystallization.
[0027]
The obtained φ3.0 mm drawn material and a φ3.0 mm extruded material that had not been drawn were cut into a length of 3 mm to obtain test pieces. These test pieces were forged in the direction of the linear axis at various rolling reductions. At this time, each test piece was heated to various temperatures in the range of 100 ° C. to 250 ° C. to perform forging. And it was investigated whether forging was possible. The result is shown in FIG. In FIG. 1, ○ indicates that forging was possible, × indicates that forging was not possible due to cracks, etc., Δ indicates that forging was possible but the heating temperature was high and the life of the mold Indicates what is problematic in terms of dots. Further, in FIG. 1, Equation (1) is T = 3r. ₁ +150, Equation (2) is T = 3r ₁ +10 is shown. In Equations (1) and (2), T is the heating temperature, r ₁ Is the rolling reduction.
[0028]
When the forging process is performed on the drawn material as shown in FIG. ₁ (%), T ≧ 3r ₁ Forging was possible by heating to a temperature T ° C. satisfying +10. That is, it can be seen that when a drawn material is used, forging can be sufficiently performed even with heating at less than 250 ° C. In particular, when the rolling reduction is about 20 to 30%, T <3r ₁ Forging could be performed sufficiently even at a temperature satisfying +150. When heated to 250 ° C., forging could be performed at any reduction rate of 20 to 80%. However, considering the life of the mold, processing by heating below 250 ° C. is desired.
[0029]
On the other hand, as shown in FIG. 1B, when the forging process is performed on the extruded material that has not been drawn, the reduction ratio r ₁ (%), T ≧ 3r ₁ Processing could not be performed unless heating satisfying +150 was performed. In particular, in the case of forging with a rolling reduction exceeding 40%, which is an industrially effective process, it is understood that heating at 250 ° C. or higher must be performed.
[0030]
A similar test was conducted on magnesium-based alloys having different compositions. That is, after the above-described drawing process was performed on the extruded material, the heat-treated drawing material was subjected to forging in the linear axis direction at various reduction rates and at various temperatures in the range of 100 to 250 ° C. The composition of the magnesium-based alloy tested is shown below.
[0031]
mass% A magnesium-based alloy containing Al: 1.2%, Zn: 0.4%, Mn: 0.3%, with the balance being Mg and impurities (ASTM symbol AZ10 equivalent material)
mass% A magnesium-based alloy containing Al: 6.4%, Zn: 1.0%, Mn: 0.28%, the balance being Mg and impurities (ASTM symbol AZ61 equivalent material)
mass% A magnesium-based alloy containing Al: 9.0%, Zn: 0.7%, Mn: 0.1% with the balance being Mg and impurities (ASTM symbol AZ91 equivalent material)
mass% Al: 1.9%, Mn: 0.45%, Si: 1.0% Magnesium-based alloy consisting of Mg and impurities (ASTM symbol AS21 equivalent material)
mass% A magnesium-based alloy containing Al: 4.2%, Mn: 0.50%, Si: 1.1%, the balance being Mg and impurities (ASTM symbol AS41 equivalent material)
mass% And containing Al: 6.1%, Mn: 0.44%, the balance being a magnesium-based alloy consisting of Mg and impurities (ASTM symbol AM60 equivalent material)
mass% Zn: 5.5%, Zr: 0.45%, and the remaining magnesium-based alloy consisting of Mg and impurities (ASTM symbol ZK60 equivalent material)
[0032]
Then, each sample has a reduction ratio r ₁ (%), T ≧ 3r ₁ Forging could be carried out by heating to a temperature T ° C. satisfying +10, and even heating below 250 ° C. could be sufficiently processed.
[0033]
(Example 2)
For a φ3.0 mm drawn material (ASTM symbol AZ31 equivalent material) produced under the same drawing conditions as in Example 1, and a φ3.0 mm extruded material (ASTM symbol AZ31 equivalent material) that has not been drawn, Swaging processing was performed. In the swaging process, each test material was heated to various temperatures in the range of 100 ° C. to 250 ° C., and φ2.7 mm (cross-sectional reduction rate 19%), φ2.4 mm (36%), φ2.3 mm (41) .2%), φ2.1mm (51%), φ1.9mm (59.9%), φ1.6mm (71.6%), φ1.4mm (78.2%) The cross-section reduction rate was changed so as to obtain a diameter. And it was investigated whether swaging processing was possible. The result is shown in FIG. In FIG. 2, ○ indicates that swaging can be performed, × indicates that cracking or the like has occurred and swaging cannot be performed, and Δ indicates that swaging can be performed but the heating temperature is high. Indicates a problem in terms of life. Further, in FIG. 2, Equation (3) is T = 3r. ₂ +150, Formula (4) is T = 3r ₂ -30. In Equations (3) and (4), T is the heating temperature, r ₂ Is the cross-sectional reduction rate.
[0034]
When swaging the drawn material as shown in FIG. ₂ (%), T ≧ 3r ₂ Swaging was possible by heating to a temperature T ° C. satisfying −30. That is, it can be seen that when the drawn material is used, sufficient swaging can be performed even with heating below 250 ° C. In particular, when the cross-section reduction rate is about 20 to 30%, T <3r ₂ Even at a temperature satisfying +150, sufficient processing was possible. In addition, when heated to 250 ° C., the swaging process could be performed at any cross-section reduction rate of 20 to 80%. However, considering the life of the mold, processing by heating at less than 250 ° C. is desirable. It is.
[0035]
On the other hand, when the swaging process is performed on the extruded material that has not been drawn as shown in FIG. ₂ Is about 20-30%, T ≧ 3r ₂ If it was not heated to the temperature T ° C. satisfying +150, it could not be processed. In particular, when the cross-section reduction rate is 40% or more, swaging cannot be performed without heating at 250 ° C. or higher.
[0036]
A similar test was conducted on magnesium-based alloys having different compositions. That is, after subjecting the extruded material to the same drawing process as in Example 1, the drawn material subjected to the heat treatment was subjected to various cross-sectional reduction ratios in a range of 100 to 250 ° C. so as to have the above seven diameters. Swaging processing was performed at various temperatures. As the magnesium-based alloy, the same AZ10 equivalent material, AZ61 equivalent material, AZ91 equivalent material, AS21 equivalent material, AS41 equivalent material, AM60 equivalent material, and ZK60 equivalent material as the components shown above were used.
[0037]
As a result of the test, the cross-section reduction rate r of any sample ₂ (%), T ≧ 3r ₂ Swaging processing could be performed by heating to a temperature T ° C. satisfying −30, and sufficient processing was possible even with heating below 250 ° C.
[0038]
(Example 3)
The φ3.0 mm drawn material (ASTM symbol AZ31 equivalent material) produced under the same drawing conditions as in Example 1 was further drawn (temperature 160 ° C., cross-sectional reduction rate per pass: about 15-18%, Temperature rising rate to 160 ° C .: about 10 ° C./sec, linear velocity: 20 m / sec), rectangular cross section (thickness t
1 mm × width 3 mm) was obtained. This wire was heat-treated at 350 ° C. for 15 minutes to obtain a test piece. Further, a rolled material having a thickness t 1 mm was prepared using the same components (ASTM symbol AZ31 equivalent material) as used in Example 1, and cut into a width of 3 mm to obtain a test piece.
[0039]
Each test piece of the obtained drawn material having a thickness t 1 mm × width 3 mm and a rolled material having a thickness t 1 mm × width 3 mm was bent at various bending radii R. The bending process was performed by heating each test piece to various temperatures in the range of 20 to 250 ° C. And it was investigated whether the bending process was possible. The result is shown in FIG. In FIG. 3, ○ indicates that bending was possible, × indicates that cracking occurred and bending was not possible, and Δ indicates that bending was possible but the heating temperature was high, and the life of the mold Shows what is wrong. In FIG. 3, Equation (5) represents T = −250 R / t + 250, and Equation (6) represents T = −250 R / t + 500. In Equations (5) and (6), T is the heating temperature, R is the bending radius, and t is the thickness of the test piece.
[0040]
When bending the drawn material as shown in FIG. 3A, the ratio R / t between the bending radius R (mm) and the thickness t (mm) of the test piece is 0.1 ≦ R / t ≦. When 1.0 is satisfied, bending was possible by heating to a temperature T ° C. that satisfies T ≧ −250 R / t + 250. In particular, when R / t is more than 1.0 and less than 2.0, bending can be sufficiently performed even at a temperature of T <−250 R / t + 500, specifically, 20 ° C. which is about room temperature. It was. Further, even when R / t was 2.0, bending could be sufficiently performed at 20 ° C. That is, it can be seen that when the drawn material is used, sufficient bending can be performed even with heating below 250 ° C. In addition, when heated to 250 ° C., bending could be performed at any R / t of 0.1 to 2.0. However, considering the life of the mold, processing by heating below 250 ° C. Is desired.
[0041]
On the other hand, as shown in FIG. 3B, when bending a rolled material that has not been drawn, T ≧ −250 R / t + 500 is satisfied even if R / t is 1.0 or more. Processing could not be performed without heating to a temperature of T ° C. Further, in the strong working with R / t of 0.5 or less, the bending work could not be performed even if heating at 250 ° C. was performed.
[0042]
A similar test was conducted on magnesium-based alloys having different compositions. That is, the same drawing process as in Example 1 was performed on the extruded material, and then the drawn material was subjected to a heat treatment after being drawn into a rectangular cross section. R / t is 0.1-2.0 Become Bending was performed at various bending radii and at various temperatures ranging from 20 to 250 ° C. As the magnesium-based alloy, the same AZ10 equivalent material, AZ61 equivalent material, AZ91 equivalent material, AS21 equivalent material, AS41 equivalent material, AM60 equivalent material, and ZK60 equivalent material as the components shown above were used.
[0043]
As a result of the test, all samples could be sufficiently bent by heating to a temperature T ° C. satisfying T ≧ −250 R / t + 250 when 0.1 ≦ R / t ≦ 1.0. Further, when 1.0 <R / t ≦ 1.9, the temperature T (° C.) is lower than −250 R / t + 500, and when R / t is 1.0 or more, the temperature is about 20 ° C. Also, it was possible to bend sufficiently. As described above, all of the samples could be sufficiently bent even when heated at less than 250 ° C.
[0044]
【The invention's effect】
As described above, according to the method for producing a magnesium-based alloy molded body of the present invention, it is possible to perform plastic working at a processing temperature of less than 250 ° C. by using a linear body obtained by drawing. Can have an effect. Therefore, the present invention does not require a high temperature such as 250 ° C. or higher during plastic processing as in the conventional case where plastic processing is performed on an extruded material or rolled material as it is. The length can be increased, and a magnesium-based alloy compact can be obtained with high productivity.
[Brief description of the drawings]
BRIEF DESCRIPTION OF DRAWINGS FIG. 1 is a graph showing whether forging can be performed when forging is performed by changing the rolling reduction at various temperatures, (a) shows a drawn material, and (b) shows an extruded material. .
FIG. 2 is a graph showing whether swaging can be performed when swaging is performed by changing the cross-section reduction rate at various temperatures, (a) is a drawing material, and (b) is extrusion. Indicates the material.
FIG. 3 is a graph showing whether bending can be performed when bending is performed by changing the ratio R / t of the bending radius R and the thickness t of the workpiece at various temperatures; (A) shows a drawn material, and (b) shows a rolled material.

Claims (7)

A step of preparing a linear body made of a magnesium-based alloy having an average crystal grain size of 10 μm or less, obtained by drawing;
A step of plastically processing the linear body at a processing temperature of less than 250 ° C. to obtain a molded body ,
The plastic working is performed at a satisfying working temperature T ° C. below, the manufacturing method of the magnesium-based alloy molded reduction ratio, characterized in that it is a forging of 20% or more.
When the rolling reduction is r ₁ % and the processing temperature is T ° C., T is
3r ₁ +150> T ≧ 3r ₁ +10
However, 20% ≦ r ₁ <80%, T <250 ° C.
Meet. A step of preparing a linear body made of a magnesium-based alloy having an average crystal grain size of 10 μm or less, obtained by drawing;
A step of plastically processing the linear body at a processing temperature of less than 250 ° C. to obtain a molded body,
The method for producing a magnesium-based alloy molded body, wherein the plastic working is a swaging process with a cross-sectional reduction rate of 20% or more, which is performed at a processing temperature T ° C. that satisfies the following conditions.
Section reduction rate is r ₂ %, Where T is the processing temperature, T is
3r ₂ +150> T ≧ 3r ₂ -30
However, 20% ≦ r ₂ ≦ 80%, T <250 ° C
Meet. A step of preparing a linear body made of a magnesium-based alloy having an average crystal grain size of 10 μm or less, obtained by drawing;
A step of plastically processing the linear body at a processing temperature of less than 250 ° C. to obtain a molded body,
The method for producing a magnesium-based alloy molded body, wherein the plastic working is a bending work with an R / t of 2.0 or less performed at a working temperature T ° C. that satisfies the following conditions.
When the thickness of the linear body during bending is t mm, the bending radius is R mm, and the processing temperature is T ° C., T is:
When 0.1 ≦ R / t ≦ 1.0, 250> T ≧ 250−250 R / t
When 1.0 <R / t ≦ 1.9, 500−250 R / t ≧ T> 0
1.9 <R / t ≦ 2.0, 25 ≧ T> 0
Meet. The method for producing a magnesium-based alloy molded body according to any one of claims 1 to 3, wherein the linear body is heat-annealed at 100 to 300 ° C for 5 to 20 minutes. The said magnesium base alloy contains 0.1-12 mass% of Al, The manufacturing method of the magnesium base alloy molded object in any one of Claims 1-4 characterized by the above-mentioned. The magnesium-based alloy is further one or more selected from Mn: 0.1 to 2.0%, Zn: 0.1 to 5.0%, and Si: 0.1 to 5.0% by mass%. The manufacturing method of the magnesium-based alloy molded object of Claim 5 characterized by the above-mentioned. The magnesium-based alloy molding according to any one of claims 1 to 4 , wherein the magnesium-based alloy contains Zn: 0.1 to 10% and Zr: 0.1 to 2.0% by mass%. Body manufacturing method.

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