Abstract: There are provided a magnesium alloy material and a method for producing the magnesium alloy material. In a magnesium (Mg) alloy material (e.g., Mg alloy sheet) having a sheet-shaped portion with a thickness of 1.5 mm or more, when a region having ¼ the thickness of the sheet-shaped portion in a thickness direction from a surface of the sheet-shaped portion is defined as a surface region and a remaining region is defined as an internal region, the ratio OF/OC of the basal plane peak ratio OF in the surface region to the basal plane peak ratio OC (degree of orientation of (002) planes) in the internal region satisfies 1.05<OF/OC. A sheet-shaped Mg alloy material is obtained by performing rolling on a twin-roll continuous cast material with multiple passes at a reduction ratio of each pass of 25% or less.

Abstract: There are provided a magnesium alloy material and a method for producing the magnesium alloy material. In a magnesium (Mg) alloy material having a sheet-shaped portion with a thickness of 1.5 mm or more, when a region having ¼ the thickness of the sheet-shaped portion in a thickness direction from a surface of the sheet-shaped portion is defined as a surface region and a remaining region is defined as an internal region, the ratio OF/OC of the basal plane peak ratio OF in the surface region to the basal plane peak ratio OC (degree of orientation of (002) planes) in the internal region satisfies 0.95?OF/OC?1.05. A sheet-shaped Mg alloy material is obtained by performing at least one pass of the rolling at a reduction ratio of 25% or more and the remaining passes of the rolling at a reduction ratio of 10% or more.

Abstract: Provided are a rolled Mg alloy material which has a wide width and whose mechanical properties are uniform in a width direction, a Mg alloy structural member produced by plastically working the rolled Mg alloy material, and a method for producing the rolled Mg alloy material. The method for producing a rolled Mg alloy material includes rolling a Mg alloy material with a reduction roll. The Mg alloy material has a width of 1,000 mm or more, and the reduction roll has three or more regions in the width direction. The temperature is controlled in each of the regions so that a difference between a maximum temperature and a minimum temperature is 10° C. or less in the width direction of a surface of the reduction roll. The variation in the rolled state in the width direction can be reduced by reducing a difference in temperature over the width direction of the reduction roll.

Abstract: Provided are a rolled Mg alloy material whose mechanical properties are locally different in a width direction, a Mg alloy structural member produced by plastically working the rolled Mg alloy material, and a method for producing the rolled Mg alloy material. The method for producing a rolled Mg alloy material includes rolling a Mg alloy material with a reduction roll. The reduction roll has three or more regions in the width direction. The temperature is controlled in each of the regions so that a difference between a maximum temperature and a minimum temperature exceeds 10° C. in the width direction of a surface of the reduction roll. The rolled state in the width direction is varied by varying a difference in temperature over the width direction of the reduction roll. As a result, it is possible to produce a rolled Mg alloy material whose mechanical properties are locally different in the width direction.

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 composite structural member having high rigidity even at a small thickness, the composite structural member being easily attachable to a target object. A composite structural member 1A includes a metal base material 10A, a resin formed article 11, and a resin film layer 12 that covers a surface of the metal base material 10A. The metal base material 10A is a plastically formed material formed by subjecting a flat sheet material having a thickness of 50 ?m or more to press forming. The metal base material 10A and the resin film layer 12 are joined together using a constituent resin of the resin formed article 11. The composite structural member 1A includes the metal base material 10A and thus can have excellent strength and rigidity even at a smaller thickness. The composite structural member 1A includes the resin formed article 11. An attaching portion to the target object can be easily formed in the resin formed article 11.

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: A magnesium alloy material having excellent impact resistance is provided. The magnesium alloy material is composed of a magnesium alloy that contains more than 7.5% by mass of Al and has a Charpy impact value of 30 J/cm2 or more. Typically, the magnesium alloy material has an elongation of 10% or more at a tension speed of 10 m/s in a high-speed tensile test. The magnesium alloy is composed of a precipitate, typically made of an intermetallic compound containing at least one of Al and Mg, and contains particles having an average particle size of 0.05 ?M or more and 1 ?m or less dispersed therein. The total area of the particles accounts for 1% by area or more and 20% by area or less. The magnesium alloy material containing fine precipitate particles dispersed therein has high impact absorption capacity through dispersion strengthening and has excellent impact resistance.

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: 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: A magnesium alloy sheet having an adequate strength and an excellent bendability is provided along with a method of manufacturing such an alloy sheet. The method comprises, rolling a magnesium alloy sheet through a reduction roll, the alloy thereof containing about 0.1-10.0 mass % of Al and about 0.1-4.0 mass % of Zn, wherein the magnesium alloy sheet has a surface temperature of about 100° C. or below at the time just before it is fed in the reduction roll, and the reduction roll has a surface temperature in the range of about 100° C. to 300° C. Particularly, when executing multipass rolling, at least the last pass is accomplished in non-preheat rolling wherein the magnesium alloy sheet and the reduction roll have specified surface temperatures, respectively.

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.