Abstract: Provided are a magnesium alloy sheet having excellent corrosion resistance and a method for producing the same. The magnesium alloy sheet has dispersed therein particles of an intermetallic compound containing an additive element (e.g., Al) and Mg (a typical example of which is Mg17Al12), and the ratio obtained by dividing the diffraction intensity of the main diffraction plane (4,1,1) of the intermetallic compound by the diffraction intensity of the c plane (0,0,2) of the Mg alloy phase in an XRD analysis of the surface of the sheet is 0.040 or more. The method for producing a magnesium alloy sheet includes the following steps: a casting step of producing a cast material composed of a magnesium alloy containing an additive element by continuous casting; a heat treatment step of holding the cast material at 400° C. or higher and then cooling the cast material at a cooling rate of 30° C.

Abstract: A magnesium alloy member having mechanical properties and corrosion resistance and a method of manufacturing the magnesium alloy member are provided. A magnesium alloy member has a base material made of a magnesium alloy, and an anticorrosive film formed on the base material. The base material is a rolled magnesium alloy including 5 to 11% by mass of Al. By using a base material including a large amount of Al, a magnesium alloy member having excellent mechanical properties and high corrosion resistance can be produced. In addition, by using a rolled material, the number of surface defects at the time of casting is small, and the frequency of compensation processes such as undercoating and puttying can be reduced.

Abstract: Provided is a composite material suitable for forming a part for continuous casting capable of producing cast materials of excellent surface quality for a long period of time and with which a molten metal is inhibited from flowing into a gap between a nozzle and a moving mold. A composite material (nozzle 1) includes a porous body 2 having a large number of pores and a filler incorporated in at least part of a portion that comes into contact with the molten metal, the portion being part of a surface portion of the porous body. The filler incorporated in the porous body 2 is at least one selected from a nitride, a carbide, and carbon.

Abstract: There is provided a lightweight, high strength impact-resistant component having a good impact energy absorptive property. The impact-resistant component is composed of a magnesium alloy containing Al in an amount of more than 7.3% by mass and 12% or less by mass. A rectangular test piece is produced from the impact-resistant component; an iron ball 30 having a mass of 225 g is allowed to freely fall toward a central portion of the test piece while both end portions of the test piece are fixed to supports 21 and 22; and, when a distance between a position from which the iron ball 30 is allowed to freely fall and the test piece is assumed to be a fall height, a fall height H at which a dent is not generated on the test piece by the iron ball 30 is measured. The impact-resistant component has a fall height H of more than 340 mm. In the impact-resistant component of the present invention, the fall height at which a dent is not generated is large.

Abstract: Magnesium-based alloy wire excelling in strength and toughness, its method of manufacture, and springs in which the magnesium-based alloy wire is utilized are made available. The magnesium-based alloy wire contains, in mass %, 0.1 to 12.0% Al, and 0.1 to 1.0% Mn, and is provided with the following constitution. Diameter d that is 0.1 mm or more and 10.0 mm or less; length L that is 1000 d or more; tensile strength that is 250 MPa or more; necking-down rate that is 15% or more; and elongation that is 6% or more. Such wire is produced by draw-forming it at a working temperature of 50° C. or more, and by heating it to a temperature of 100° C. or more and 300° C. or less after the drawing process has been performed.

Abstract: There are provided a magnesium alloy coil stock having good flatness and a method for producing the magnesium alloy coil stock, and a magnesium alloy structural member that uses the coil stock and a method for producing the magnesium alloy structural member. The coil stock is obtained by coiling a sheet composed of a magnesium alloy in a cylindrical shape, and the internal diameter of the coil stock is 1000 mm or less. When a test piece 1 for warpage amount obtained by cutting the coil stock is paced on a horizontal table 100, the ratio of the maximum distance h in a vertical direction regarding a gap 110 between the test piece 1 and the horizontal table 100 relative to the width w of the test piece 1 is 0.5% or less. The coil stock can be produced by rolling a cast material obtained by subjecting a magnesium alloy to continuous casting, subjecting the rolled sheet to warm leveling, and coiling the worked sheet in a cylindrical shape while the temperature just before coiling is decreased to 100° C. or less.

Abstract: An alloy screw producing method includes a head forging step in which a head working for forming a head portion of a screw on a wire made of magnesium-based alloy obtained by drawing is carried out by warm working to produce a screw blank, and a thread rolling step in which thread rolling for forming screw thread on the screw blank is carried out by warm working to produce a screw. The head working in the head forging step is carried out using holding die which fixes the wire and a punch which forms a head portion of the screw. The holding die and the punch are heated, in which at least the holding die are heated to 140° C. or higher and 250° C. or lower.

Abstract: There are provided a method for producing a magnesium alloy sheet having good press formability and a magnesium alloy coil stock obtained by coiling the magnesium alloy sheet. After a raw material sheet 1 composed of a magnesium alloy is preheated to 280° C. or less, the heated raw material sheet 1 is rolled with a reduction roll 3 and the obtained long rolled sheet is coiled. The surface temperature of the reduction roll 3 is set to be 230° C. or more and 290° C. or less. The preheating, rolling, and coiling are repeatedly performed in a continuous manner. By setting both the temperatures of the raw material sheet 1 and reduction roll 3 to be certain temperatures, the rolling property of the raw material sheet can be improved and the raw material sheet can be properly rolled in a continuous manner. In addition, a variation in temperature in the width direction of the reduction roll can be suppressed and uniform rolling can be performed, resulting in the production of a long magnesium alloy sheet.

Abstract: A coil material capable of contributing to an improvement of the productivity of a high-strength magnesium alloy sheet and a method for manufacturing the coil material are provided. Regarding the method for manufacturing a coil material through coiling of a sheet material formed from a metal into the shape of a cylinder, so as to produce the coil material, the sheet material is a cast material of a magnesium alloy discharged from a continuous casting machine and the thickness t (mm) thereof is 7 mm or less. The sheet material 1 is coiled with a coiler while the temperature T (° C.) of the sheet material 1 just before coiling is controlled to be a temperature at which the surface strain ((t/R)×100) represented by the thickness t and the bending radius R (mm) of the sheet material 1 becomes less than or equal to the elongation at room temperature of the sheet material 1.

Abstract: The method of producing a magnesium alloy joined part has the following steps: a joining step of joining a reinforcing material made of metal to a plate material made of magnesium alloy without allowing an organic material to remain at the joined portion and a plastic-working step of performing plastic working on the plate material to which the reinforcing material is joined. A desirable means of joining the reinforcing material to the plate material can be to use an inorganic adhesive. Because the magnesium alloy joined part is formed by a structure in which the reinforcing material is joined to the plate material, in comparison with the case where the reinforcing material is formed by machining or the like, the magnesium alloy structural member can be obtained with high production efficiency.

Abstract: A magnesium alloy sheet having good press formability, a magnesium alloy structural member produced by pressing the sheet, and a method for producing a magnesium alloy sheet are provided. The magnesium alloy sheet is composed of a magnesium alloy containing Al and Mn. When a region from a surface of the alloy sheet to 30% of the thickness of the alloy sheet in a thickness direction of the magnesium alloy sheet is defined as a surface region and when a 200 ?m2 sub-region is arbitrarily selected from this surface region, the number precipitated impurity grains containing both Al and Mg and having a maximum diameter of 0.5 to 5 ?m is 5 or less. When a 50 ?m2 subregion is arbitrarily selected from the surface region, the number of crystallized impurity grains containing both Al and Mn and having a maximum diameter of 0.1 to 1 ?m is 15 or less. In the grains of the crystallized phases, the mass ratio Al/Mn of Al to Mn is 2 to 5.

Abstract: A magnesium alloy sheet having high impact resistance at low temperature, a magnesium alloy structural member using this sheet, and a method for producing a magnesium alloy sheet are provided. The magnesium alloy sheet is composed of a magnesium alloy containing Al and Mn. When a region from a surface of the alloy sheet to 30% of the thickness of the alloy sheet in a thickness direction of the magnesium alloy sheet is defined as a surface region and when a 50 ?m2 sub-region is arbitrarily selected from this surface region, the number of grains that are crystallized phases containing both Al and Mn is 15 or less. The maximum diameter of each of the crystallized phases is 0.1 to 1 ?m and the mass ratio Al/Mn of Al to Mn is 2 to 5. This magnesium alloy sheet has high impact resistance since it contains crystallized phases that are small in size and in amount contained and cause breaking and the like, and exhibits good mechanical properties even in a low-temperature environment.

Abstract: A magnesium alloy structural member includes a base material composed of a magnesium alloy having an aluminum content of 4.5% by mass to 11% by mass, in which the base material has a pair of first and second surfaces, the first surface and the second surface being opposite each other, in which when a distance between the first surface and the second surface is defined as a thickness and when surface area regions are defined as regions extending from the first and second surfaces to positions 20 ?m from the respective first and second surfaces in the thickness direction, in at least both the surface area regions, 10 or more fine precipitates are present in any 20 ?m×20 ?m subregion of each of the surface area regions, each of the fine precipitates containing both Mg and Al and having a greatest dimension of 0.5 ?m to 3 ?m.

Abstract: The method of producing a magnesium alloy joined part has the following steps: a joining step of joining a reinforcing material made of metal to a plate material made of magnesium alloy without allowing an organic material to remain at the joined portion and a plastic-working step of performing plastic working on the plate material to which the reinforcing material is joined. A desirable means of joining the reinforcing material to the plate material can be to use an inorganic adhesive. Because the magnesium alloy joined part is formed by a structure in which the reinforcing material is joined to the plate material, in comparison with the case where the reinforcing material is formed by machining or the like, the magnesium alloy structural member can be obtained with high production efficiency.

Abstract: A plurality of magnesium alloy parts are joined to one another through an inorganic joining layer (an reinforcing material 2, a boss 3, and a pin 4 are joined to a base material 1). Concrete examples of the inorganic joining layer include a layer of an inorganic adhesive and a metal thin film formed on the magnesium alloy part at the time of hot cladding. Because the magnesium alloy parts are joined together through the inorganic joining layer, in comparison with the case where a reinforcing material and the like are formed by machining, waste of the material can be reduced. The use of the inorganic joining layer can produce a magnesium alloy structural member that does not generate hazardous smoke and soot even when it is melted for recycling.

Abstract: There is provided a magnesium alloy member having mechanical properties and corrosion resistance and a method of manufacturing the magnesium alloy member. A magnesium alloy member has a base material made of a magnesium alloy, and an anticorrosive film formed on the base material. The base material is a rolled magnesium alloy including 5 to 11% by mass of Al. By using a base material including a large amount of Al, a magnesium alloy member having excellent mechanical properties and high corrosion resistance can be produced. In addition, by using a rolled material, the number of surface defects at the time of casting is small, and the frequency of compensation processes such as undercoating and puttying can be reduced.

Abstract: A formed product of a magnesium alloy having excellent impact resistance and a magnesium alloy sheet suitable as a material for the formed product are provided. The formed product is produced by press-forming a magnesium alloy sheet having an Al content of 7% by mass to 12% by mass and has a flat portion that is not subjected to drawing deformation. In a metal texture in a cross section of the flat portion in the thickness direction, the number of coarse intermetallic compound (Mg17Al12) particles having a particle size of 5 ?m or more present in a surface area region extending from a surface of the flat portion to a position one-third of the thickness from the surface in the thickness direction is five or less. The formed product has a texture in which the number of coarse precipitations d1 is small and in which fine precipitations d0 are dispersed.

Abstract: The invention offers a magnesium alloy sheet having excellent warm plastic formability, a production method thereof, and a formed body produced by performing warm plastic forming on this sheet. The magnesium alloy sheet is produced by giving a predetermined strain to a rolled sheet RS that is not subjected to a heat treatment aiming at recrystallization. The sheet is not subjected to the foregoing heat treatment even after the giving of a strain. The strain is given through the process described below. A rolled sheet RS is heated in a heating furnace 10. The heated rolled sheet RS is passed between rollers 21 to give bending to the rolled sheet RS. The giving of a strain is performed such that the strain-given sheet has a half peak width of 0.20 deg or more and 0.59 deg or less in a (0004) diffraction peak in monochromatic X-ray diffraction. The alloy sheet exhibits high plastic deformability by forming continuous recrystallization during warm plastic forming through the use of the remaining strain.

Abstract: The invention offers a pressed product (F) produced by press-forming a metal plate (1). The pressed product (F) has a peripheral surface that has a corner portion (12) connecting two surfaces in the peripheral surface. The corner portion (12) has an outside corner radius R that is equal to or smaller than the thickness “t” of the metal plate (1). That is, the pressed product (F) has the sharp corner portion (12).

Abstract: The invention offers a magnesium alloy structural member having a high metallic texture. The magnesium alloy structural member is provided with a base material made of magnesium alloy and a covering layer formed on the base material. The base material is provided, in at least one part of its surface, with a surface-processed portion that is subjected to a fine asperity-forming processing so as to obtain a metallic texture. The covering layer is transparent. The structural member can effectively increase the metallic texture by having the surface-processed portion. Because the structural member is provided with the covering layer, it has excellent corrosion resistance. Because the covering layer is transparent, the metallic texture in the surface-processed portion is readily sensed. The asperity-forming processing is performed through hairline finish, diamond cut finish, and the like.