JP5640363B2 - Magnesium alloy rolled plate straightening method and straightening machine, magnesium alloy rolled plate manufacturing method - Google Patents

Description

  The present invention relates to a method for manufacturing a magnesium alloy rolled sheet, and particularly to a method for correcting an aluminum alloy rolled sheet having a high aluminum ratio.

  Magnesium alloys have been studied as housing materials for electric devices such as mobile phones and portable computers. Magnesium alloys have features such as lighter weight, stronger strength than weight, and shock absorption compared to conventional resin casings, aluminum alloys, and stainless steel casing materials. Because of these characteristics, it is expected not only for electric devices but also as exterior and interior materials for automobiles and railways. Conventionally, a casing made of a magnesium alloy is generally formed of a cast material by a die casting method or a thixo mold method. This is because the magnesium alloy has a crystal structure of fine hexagonal crystals and is inferior in plastic workability at room temperature. However, it is difficult to produce a thin plate material by casting using a die casting method or the like, and there are problems such that the surface becomes rough due to an increase in the crystal grain size and breaks easily during processing. Therefore, various materials and manufacturing methods for forming and rolling a plate made of AZ31 alloy of ASTM (American Society for Testing and Materials) standard have been studied (for example, patents). Literature 1, Patent Literature 2).

  The inventors of the present application have also studied a method for producing a rolled material suitable for press working by using an alloy material equivalent to AZ91 as a stretched material having a high aluminum content and excellent corrosion resistance and strength. For example, in Patent Document 2, a magnesium alloy material plate obtained from a twin-roll casting material or the like is rolled with a rolling roll so as to suppress the coarsening of crystal grains and to prevent cracks from occurring on the surface. A method is disclosed.

Japanese Patent No. 3821074 Japanese Patent No. 3659208 JP 2007-98470 A

  Thus, although a method for producing a thin plate by rolling a magnesium alloy material has been studied, the yield at the time of production is still not sufficient for practical use. In particular, when a large amount of aluminum is included as an alloy component, defects such as cracks are likely to occur in mechanical processing because the plastic deformability is inferior compared to an alloy having a low aluminum ratio, which has been a factor in yield reduction.

  The inventors of the present application have arrived at the present invention while paying attention to the yield in the correction process after rolling while studying the manufacturing process. That is, it is possible to provide a rolled sheet with few defects as a product after correction, ascertaining that one of the causes of defects such as cracks in the straightening process is caused by defects at both ends of the rolled sheet. .

  The first invention of the present application includes a supply preparation step of preparing a rolled plate of a coil-shaped magnesium alloy so that the rolled plate can be fed, a warm correction step of correcting the rolled plate with a plurality of rolls in a heated state, and the correction And a winding process for winding up the rolled sheet material, and an end part for continuously cutting both side edges of the rolled sheet before the warming process. A magnesium alloy rolled sheet straightening method comprising a removing step (claim 1).

  The rolled magnesium alloy sheet after rolling has a warp in the width direction due to residual strain during processing, a winding in the length direction due to coil winding, and the like, which affects the flatness when cut as a plate material. The straightening process is a process for removing such distortion, and a straightening process using a roller leveler, which performs straightening by passing a rolled plate between a plurality of upper and lower rolls, is generally used. Magnesium alloys are hard as described above and are characterized by being easily cracked in plastic working. In relation to this characteristic, the magnesium alloy rolled sheet that has been rolled from casting is dotted with numerous indentations and cracks at both ends. When passing through a roller leveler in the straightening process, starting from the cracks at both side ends, the cracks progress further, so the cracks from both ends become deep, and it is impossible to secure the necessary plate width as a good product. They paid attention. Therefore, as in the present invention, prior to the straightening step, both ends of the rolled plate are cut and removed (hereinafter also referred to as “trimming” in the present specification), so that the starting point of the crack is eliminated and the ends of the both ends are removed. It becomes possible to obtain a plate material having no defects.

  When the rolled sheet is a rolled sheet produced by subjecting a cast material, which is a magnesium alloy containing 5% by mass or more of aluminum, to roll rolling (Claim 2), the effect of the first invention can be further enhanced. .

  In a magnesium alloy containing 5% by mass or more of aluminum, plastic processing is particularly difficult, and cracks and the like during processing are likely to occur. Therefore, the effect of cutting both end portions of the rolled plate before correction is greatly exhibited in the correction process. In particular, in AZ91 (alloy material containing about 9% aluminum and about 1% zinc) defined in the ASTM standard, a manufacturing method with a higher yield than before is desired, and the yield is greatly improved by applying the above process. Can be expected.

  The warm straightening step may include a preheating step of heating the fed rolled plate before straightening, and a roll straightening step of correcting the preheated rolled plate with a plurality of rolls (Claim 3).

  In the case of a magnesium alloy, plastic deformation is easier particularly when heated to about 150 ° C. to about 300 ° C. In particular, it is preferable to provide a preheating step before passing through a roll for correcting the roll, and to heat the roll itself from the viewpoint of preventing defects such as cracks during correction.

  Before the end removing step, an end position detecting step for controlling the position to be cut by detecting the end position of the rolled-out rolled sheet, that is, detecting the position in the width direction of the rolled sheet, is provided. (Claim 4).

  The rolled sheet fed out from the coil has a dimensional variation in the width direction and a positional deviation in the width direction due to uneven winding. If the end of such a coil is to be cut with a cutter whose position is fixed, it will be necessary to cut the coil with a margin at both ends. For example, when the necessary plate width after cutting is 210 mm and the cutting width considering the unevenness at both side ends is 10 mm, it is only necessary to supply a 230 mm rolled plate, but there is ± 10 mm of winding deviation. If so, it is necessary to prepare a 250 mm rolled sheet with a margin of 10 mm on the left and right sides. Here, if a sensor that detects the position in the width direction from the end position of the rolled sheet fed from the supply is provided, and the left and right positions of the supply are controlled according to the detection position, ideally ± It is sufficient to prepare a rolled plate having a width of 230 mm without requiring 10 mm.

  Further, the second invention of the present application is a casting process in which a magnesium alloy material is melted and a rolling base material is continuously cast by twin roll casting, and the rolling base material is rolled to form a coiled magnesium alloy rolled plate. A rolling step, a straightening step for warm-correcting the magnesium alloy rolled plate, and a polishing step for polishing the warm-corrected magnesium alloy rolled plate, wherein the straightening step is performed by the correction method described above. It is a manufacturing method of the magnesium alloy rolled sheet which is the process of giving warm correction (Claim 5).

  By manufacturing the magnesium alloy rolled sheet in this way, the yield in the straightening process is improved, and a desired magnesium alloy rolled sheet can be obtained efficiently.

  Furthermore, the third invention of the present application is a supply unit for holding a rolled plate of a coil-shaped magnesium alloy so that the rolled plate can be fed, and an end removing unit for continuously cutting both side ends of the rolled plate fed from the supply unit. And a magnesium alloy rolled plate comprising a warm straightening portion that is straightened by a plurality of rolls in a heated state of the rolled plate having both side edges cut, and a winding portion that winds the straightened rolled plate. A straightening machine (claim 6).

  As described above, according to the present straightening machine, it is possible to efficiently produce a magnesium alloy rolled sheet with few uneven defects such as cracks that are likely to occur at both ends in the width direction in the conventional straightening process.

  According to the invention of the present application, in the production of a magnesium alloy rolled plate, it is possible to provide a rolled plate with less uneven defects such as cracks at both end portions in the plate width direction with a higher yield than before.

It is a figure explaining the structure of the straightening machine provided with the correction method of the magnesium alloy rolled sheet by this invention. It is a figure which illustrates the structure of trimming typically, (a) is the figure which looked at the rolled sheet from the top, (b) is the figure seen from the conveyance direction. It is a figure explaining the state of the rolled-sheet edge part cut | judged by trimming. It is a figure explaining plate width detection in a trimming device typically, (a) is a figure which looked at a rolled sheet from the horizontal direction, and (b) is a figure seen from the top. It is a figure which shows the structure of an edge part detector. It is a figure explaining an effect | action of an edge part detector and a board width detection apparatus.

  Below, the manufacturing method of a magnesium alloy rolled sheet including the correction method of the magnesium alloy rolled sheet concerning this invention is demonstrated. Here, as an example, a method for producing the AZ91 material, in which the effect of the present invention is remarkable, is shown, but the present invention is not limited to this, and is shown by the scope of the claims, meaning equivalent to the scope of the claims. And all changes within the scope are intended to be included.

"composition"
Examples of the magnesium alloy include those having various compositions containing an additive element in Mg (the balance other than the additive element is Mg and inevitable impurities). The plate according to the present invention is made of an Mg—Al-based alloy containing at least 5 mass% to 12 mass% of Al as an additive element. Examples of the additive element other than Al include one or more elements selected from Zn, Mn, Si, Ca, Sr, Cu, Ag, and rare earth elements. When these elements are contained, the content is 0.01% by mass or more and 10% by mass or less, preferably 0.1% by mass or more and 5% by mass or less. More specific Mg-Al alloys include, for example, AZ-based alloys (Mg-Al-Zn-based alloys, Zn: 0.2 to 1.5 mass%) and AM-based alloys (Mg-Al-Mn) according to ASTM standards. Alloy, Mn: 0.15 to 0.5 mass%), Mg-Al-RE (rare earth element) alloy, and the like. In particular, an Mg—Al alloy containing 8.3 to 9.5 mass% Al and 0.5 to 1.5 mass% Zn, typically AZ91 alloy is another Mg—Al alloy such as AZ31 alloy. Compared to alloys, it has excellent mechanical properties such as corrosion resistance, strength, and plastic deformation resistance. On the other hand, it is hard and inferior in plastic workability because of its large Al composition ratio. The effect of applying the invention is great. That is, the present invention is preferably applied to a magnesium alloy containing 5% by mass or more of Al, more preferably, a magnesium alloy having an Al content of 7% by mass or more, particularly preferably 9% by mass or more.

<Magnesium alloy rolled plate size>
The magnesium alloy rolled plate to which the present invention is applied is a rolled plate provided in a coil shape and is wound up again, or cut into a plate shape, and its width is related to the equipment to be manufactured. If it can manufacture, it will not specifically limit. On the other hand, the magnesium alloy rolled plate targeted by the present invention is subjected to press forming such as bending and drawing, and is often used as a material for a thin and lightweight member such as a casing. For this reason, the thickness of the rolled plate is preferably 2.0 mm or less, particularly 1.5 mm or less, and more preferably 1 mm or less.

"Production method"
[Preparation process]
As the cast plate, it is preferable to use a cast plate produced by a continuous casting method such as a twin roll method, in particular, a casting method described in WO / 2006/003899. Since the continuous casting method can be rapidly solidified, it is possible to reduce oxides and segregation and to obtain a cast plate having excellent rolling properties. The size of the cast plate is not particularly limited, but segregation is likely to occur if it is too thick, and is preferably 10 mm or less, particularly 5 mm or less.

[Heat treatment process]
The cast plate is subjected to a solution treatment so as to homogenize the composition. The solution treatment is performed at a holding temperature of 350 ° C. or higher. In particular, the holding temperature is preferably 380 to 420 ° C. and the holding time is 60 to 2400 minutes, and the holding time is preferably increased as the Al content is higher.

[Rolling process]
The plate material subjected to the solution treatment is rolled to produce a thin plate. In order to improve plastic workability (rollability), it is preferable to perform rolling in a state where at least the plate material is heated to a temperature of 250 ° C. or higher. The higher the heating temperature, the higher the plastic workability, but if it exceeds 350 ° C, there is a problem such as seizure occurring or the crystal grains coarsen and the mechanical properties of the plate after rolling deteriorate. 350 degreeC or less is preferable and more preferable heating temperature is 270 degreeC or more and 330 degrees C or less. By carrying out rolling a plurality of times (multi-pass), it is possible to achieve a desired plate thickness, to reduce the average crystal grain size, and to improve press workability.

[Correction process]
The distortion is corrected by applying a predetermined strain to the rolled sheet. A roller leveler is preferably used for correction. A roller leveler is provided with one or more rollers and imparts bending with the rollers. In particular, a roller leveler can be repeatedly bent by passing the rolled plate between rollers arranged in a staggered manner. Is preferably used. More preferably, the roller is a heating means, for example, one having a heater. The amount of distortion applied for correction can be adjusted by adjusting the size and number of rollers, the interval between rollers, and the like.

FIG. 1 is a diagram schematically illustrating a configuration of a straightening machine including a straightening method according to the present invention. At the left end of the figure, a supply device 10 is arranged in which the magnesium alloy rolled plate 1 rolled in the above-described process and wound in a coil shape is prepared so as to be able to be fed out. The rolled plate 1 typically has a width of 200 mm to 350 mm and a plate thickness of 0.2 mm to 1.0 mm.
From the supply device 10, the magnesium alloy rolled sheet 1 is fed out by means such as driving of the supply or drawing of the coil material, and supplied to the trimming device 20. As described above, the present invention is characterized in that both end portions in the width direction of the plate material are continuously cut by the trimming device before the plate material supplied from the supply is distorted by a roller leveler or the like. The trimming device 20 will be described later.

  The plate cut by the trimming device is then heated to a temperature suitable for correction by the preheating device 30 in order to perform warm correction. The heating means is not particularly limited, but a method using electromagnetic induction or a method using hot air is preferably used. Thus, the application of strain is performed in a state where the rolled plate is heated. The specific heating temperature is preferably 100 ° C. or higher and 250 ° C. or lower. Below 100 ° C including normal temperature, the amount of applied strain becomes excessive, and dislocation density increases during subsequent warm plastic processing, resulting in work hardening, and in addition to breakage, cracking occurs when strain is applied. There is a fear. If it exceeds 250 ° C., the amount of strain applied is small, and there is a disadvantage that continuous recrystallization hardly occurs during warm plastic working. More preferably, it is 150 degreeC or more and 200 degrees C or less.

  Here, it is preferable that the roller itself of the roller leveler 40 is also heated. The specific heating temperature is preferably 150 ° C. or higher and 300 ° C. or lower. If it is less than 150 degreeC including normal temperature, it will be difficult to maintain a rolled sheet at desired temperature, the temperature of a rolled sheet will fall, and the distortion amount provided as mentioned above will become excessive easily, and if it exceeds 300 degreeC, As the temperature rises, the strain applied as described above tends to be small. More preferably, it is 200 degreeC or more and 250 degrees C or less.

  The roller leveler 40 is a device that applies a bending strain by arranging a plurality of rollers 41 and 42 in a staggered manner and passing a plate material therebetween. What is necessary is just to select the magnitude | size and number of rollers according to conditions, such as the material of a board made into object, a size, and the distortion amount to give. As an example, there are 20 upper rolls 42 and 21 lower rolls 41, for a total of 41 rolls (FIG. 1 shows the number of rolls in a simplified manner), each roll having a diameter of 40 mm, the center of the upper and lower rolls. The horizontal distance between them is 43 mm. The roll interval (the vertical distance between the centers of the upper roll and the lower roll) is preferably changed linearly from the upstream side to the downstream side of the roll part. Specifically, the roll interval is narrower toward the upstream side and wider toward the downstream side, and the roll interval on the side of introducing the rolled plate conveyed from the preheating device 30 is 39 mm. The roll interval on the side discharged to the outside is preferably 41 mm.

  The rolled magnesium alloy sheet 1 that has been distorted by the roller leveler and has been corrected is wound into a coil shape by the winding device 50 again. In the above description, an accompanying device is omitted. For example, a laverbera for taking up the rolled plate 1 fed from the supply device 10 is provided in front of the trimming device 20, cutting waste cut by trimming is collected in front of the preheating device, and other devices that are attached. Provision is made as appropriate.

[Trimming device]
FIG. 2 is a schematic diagram for explaining the function of the trimming apparatus. 2A is a view of the rolled plate 1 in the trimming apparatus as viewed from above, and FIG. 2B is a view of the rolled plate 1 as viewed from the rear. Although the cutting part 21 corresponding to the blade to be cut here is schematically shown in the upper part of the rolled plate for explanation, it does not represent the structure of the cutting part 21 but shows the cutting position. Rolled sheet 1 (width L1) fed out from the supply and conveyed in the direction of the arrow is cut into a constant width L2 by cutting portions 21 provided at both end portions in the width direction. In this example, L1 is 200 mm to 350 mm, both ends are cut by 10 to 15 mm, and L2 is about 170 mm to 320 mm. The cutting unit 21 is a cutting device generally used for cutting a metal plate, such as a disk cutter or a laser cutter. FIG. 3 shows an enlarged explanatory view of the end portion to be cut. There are many irregularities 2 due to cracks, chips, etc. at both ends of the magnesium alloy rolled sheet 1. The trimming apparatus is an apparatus for finishing a rolled sheet to a sheet width L2 as a product and removing such irregularities and supplying a rolled sheet without irregularities to the distortion applying step. By supplying a rolled plate without unevenness to the strain applying step in this way, in the strain applying step, cracks and the like at the end progress and the unevenness 2 becomes larger (deeper), which means that it is easy to crack unique to the magnesium alloy rolled plate. It prevents problems. Therefore, the defect rate after cutting is reduced, and the manufacturing yield can be improved.

  Here, the trimming apparatus preferably includes a plate width detecting means. FIG. 4 shows the flow of the rolled plate 1 from the supply device 10 to the cutting part 21. FIG. 4A is a view of the rolled plate viewed from the side, and FIG. 4B is a view of the rolled plate viewed from above. As described above, both end portions of the rolled plate are cut at the cutting portion 21. If there is winding unevenness on the coiled rolled plate provided for the supply, the rolled plate conveyed to the cutting portion is equivalent to the winding unevenness. The position will shift in the left-right width direction. The length indicated by d in FIG. 4B is the maximum value of winding unevenness. That is, the cutting width from the edge of the plate on both side edges to be cut is shifted by the width of the winding unevenness d. When the winding unevenness d is large, the unevenness at both end portions that are originally intended to be cut is not appropriately cut, and in order to prevent this, it is necessary to increase the width of the coiled rolled plate in advance. In FIG. 4, a sheet width detection device 22 is provided in front of the cutting part 21, and the positional relationship in the width direction between the cutting part and the rolled sheet is measured by detecting both side ends. An existing laser sensor or image sensor can be applied to the plate width detection device 22. The measurement result is fed back to the shaft drive of the supply device, the shaft 11 of the coiled rolled plate is displaced in the width direction, and the feed position is adjusted (not shown), thereby the width direction of the rolled plate reaching the cutting part 21. The position can be stabilized.

  The main object of the plate width detecting device is to detect the displacement in the width direction of the rolled plate, in other words, the center position of the plate, and therefore it is not always necessary to measure the plate width itself. In addition, it is not always necessary to detect the positions of both end portions. FIG. 5 shows an end detector preferably used in the plate width detecting device. This detector detects the displacement of the end position by mechanically pressing the roller against the side edge of the rolled plate and measuring the position displacement of the roller. By giving a characteristic to the diameter and configuration of the roller, it is possible to detect an average position change in the width direction of the plate without being affected by irregularities such as fine cracks at the end.

  The configuration of FIG. 5 will be described. Two rollers 61a and 61b are connected to each other by upper and lower connecting members 62 so that the shafts can rotate. Between the connecting members 62, the vertical connecting members 63 are fixedly or pivotably attached. A shielding plate 65 is attached to the vertical connecting member.

  FIG. 6 is a schematic diagram for explaining the functions of the end detector and the plate width detecting device. FIG. 6A is a diagram for explaining a state in which the end detector pressed against the side edge of the rolled plate is viewed from above the plate, and FIG. 6B is also viewed horizontally from the traveling direction of the rolled plate. FIG. Here, the plate width detection function is schematically shown together. The following description will be given with reference to these figures. A roller 61 a and a roller 61 b are pressed against the end by a spring 80 so as to follow the end of the rolled plate 1. In the figure, the unevenness 2 at the end of the rolled plate is schematically shown. As the spring 80, a coil spring, a leaf spring, and other elastic members can be applied as long as they act in a direction to press the vertical connecting member of the end detector in the direction of the rolling plate. The shielding plate 65 is fixed to the vertical connecting member, and when the roller is displaced along the end of the rolled plate, the shielding plate 65 is also displaced in the plate width direction. Such displacement of the shielding plate is detected by a light beam detector. The light beam detector includes a light source unit 71 and a light receiving unit 72, and receives and measures the intensity of parallel light emitted from the light source unit 71 by the light receiving unit 72. A region 70 indicated by a dotted line in FIG. 6A indicates a range of light rays from the light source unit 71 to the light receiving unit 72. The shielding plate 65 is arranged so as to block the region 70, and the area of the blocking region changes according to the displacement of the shielding plate, that is, the displacement of the roller that follows the end of the rolled plate. Therefore, the change in the end position of the rolled sheet can be detected from the change in the received light intensity.

  Here, if the width of the plate can be treated as being constant, by placing a plate width detection device only at one end of the plate, by taking a distance of 1/2 of the constant plate width from the detected end. Since the center of the plate is required, if the supply of the rolled plate is changed in accordance with the displacement of the plate center, the rolled plate can be fed out with the center kept constant. On the other hand, when the plate width itself may vary, by placing this plate width detection device at both ends, it is possible to detect a change in the plate width as well as the displacement of the center position. Based on the principle as described above, a plate width detection apparatus using the end detector of FIG. 5 can be configured.

  One feature of the end detector is the diameter of the roller. There are many irregularities such as cracks to be cut off at the end of the rolled sheet. Such irregularities have a depth of about several millimeters to several tens of millimeters and are not periodic, but on average, occur at a pitch of about 5 to 10 mm. The purpose of edge detection is not the detection of irregularities such as cracks, but the positional deviation in the width direction of the entire plate (the center position of the plate width), and it is preferable that it is not affected by such irregularities. Therefore, by setting the diameter of the roller to be twice or more the average pitch of the unevenness, it is possible to detect a change in the position in the width direction of the entire plate without following the fine unevenness. The upper limit of the roller diameter may be designed in consideration of installation and arrangement on the equipment, but if it is too large, the weight of the roller itself increases, and the force for pressing the roller against the plate increases. When the side edge of the plate is pressed with a large force, there is an adverse effect such as further chipping of the aforementioned irregularities such as cracks. Therefore, the diameter of the roller is 2 to 10 times, preferably 2 to 5 times the uneven pitch. Here, the pitch of the unevenness is determined by measuring the number of the bottoms (valleys) of the recesses that occur in a predetermined length of the plate (preferably 50 times or more of the assumed pitch, for example, 1 m), and the predetermined length is the bottom of the recesses. It can be obtained as a value divided by the number of. In this example, the roller diameter was 30 mm and the roller length was 40 mm.

  Next, the second feature is that two rollers are used. When there is only one roller, the roller shaft does not follow the unevenness that is smaller than the roller diameter, but it follows the tip of the convex portion as it is. However, by detecting the displacement of the connecting member using a plurality of rollers, it is possible to detect the average displacement of the plurality of rollers. Therefore, it is possible to capture a change in the end portion more like an average envelope. Typically, it is convenient and preferable to measure the change in the center position of the connecting member with two rollers. In this example, the roller interval was 200 mm.

Hereinafter, the edge detector and the plate width detection device used in the present invention as the specific embodiments described above will be summarized as appendices.
(Appendix 1)
It has one or a plurality of rollers arranged so that the outer surface is in contact with the side end portion of the rolled plate to be detected and is displaced in the plate width direction according to the shape change in the plate width direction of the side end portion. A plate width detection apparatus comprising an end detector and a displacement detector that detects a displacement of the roller in the plate width direction.
(Appendix 2)
The diameter of the said roller is a board width detection apparatus which is 2 to 5 times the average pitch of the unevenness | corrugation of the side edge part of the said rolled sheet.
(Appendix 3)
The number of the rollers is two, and the two rollers are connected to each other by a connecting member, and the displacement detector is configured to detect the displacement of the connecting member. .

1 Magnesium alloy rolled plate 2 Concavity and convexity 10 Supply device 11 Shaft 20 Trimming device 21 Cutting part 22 Plate width detection device 30 Preheating device 40 Roller levelers 41 and 42 Roller 50 Winding devices 61a and 61b Roller 62 Connecting member 63 Vertical connecting member 65 Shielding Plate 71 Light source portion 72 Light receiving portion 70 Area 80 Spring

Claims (6)

A supply preparation process for preparing a rolled plate of a coil-shaped magnesium alloy so that it can be fed out;
A warm straightening step of straightening with a plurality of rolls in a heated state of the rolled sheet;
A method for correcting a magnesium alloy comprising a winding step of winding the straightened plate material,
Before the warm straightening step, a magnesium alloy comprising an end portion removing step of continuously cutting the both side end portions of the rolled-out rolled sheet so as to remove defects at both end portions. How to straighten rolled plates.   2. The method for correcting a magnesium alloy rolled plate according to claim 1, wherein the rolled plate is a rolled plate produced by subjecting a cast material, which is a magnesium alloy containing 5% by mass or more of aluminum, to roll rolling. . The warm straightening step includes a preheating step of heating the rolled-out rolled sheet before straightening,
The method for straightening a magnesium alloy rolled sheet according to claim 1 or 2, comprising a roll straightening step of straightening the preheated rolled sheet with a plurality of rolls. The end position detecting step of detecting an end position of the rolled-out rolled sheet and controlling a cutting position is provided before the end removing step. The correction method of the magnesium alloy rolled sheet of any one of Claims 1. A casting process in which a magnesium alloy material is melted and a rolling base material is continuously cast by twin roll casting;
A rolling step of rolling the base material for rolling to form a coiled magnesium alloy rolled plate;
A straightening process for warm straightening the rolled magnesium alloy sheet;
Polishing step for polishing the warm-adjusted magnesium alloy rolled plate,
The method for producing a magnesium alloy rolled sheet, wherein the straightening step is a step of performing warm straightening by the straightening method according to any one of claims 1 to 4. A supply unit that holds a rolled plate of a coil-shaped magnesium alloy so that it can be fed out;
An end removing unit that continuously cuts both side ends of the rolled sheet fed from the supply unit;
A warm straightening portion that is straightened by a plurality of rolls in a heated state of the rolled plate whose both ends are cut;
A winding portion for winding the straightened rolled plate ,
A magnesium alloy rolled plate straightening machine in which the end removing section is disposed between the supply section and the warm straightening section .

Images