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.

Abstract: The present invention provides a method for producing a magnesium alloy sheet capable of producing a magnesium alloy sheet having excellent plastic workability such as press workability. The method of the present invention includes rolling a magnesium alloy blank with a reduction roll. The rolling includes controlled rolling performed under the following conditions (1) and (2) wherein M (% by mass) is the Al content in a magnesium alloy constituting the blank: (1) the surface temperature Tb (° C.) of the magnesium alloy blank immediately before insertion into the reduction roll satisfies the following expression: 8.33×M+135?Tb?8.33×M+165 wherein 1.0?M?10.0; and (2) the surface temperature Tr of the reduction roll is 150° C. to 180° C.

Abstract: The present invention provides a method for producing a magnesium alloy sheet capable of producing a magnesium alloy sheet having excellent plastic workability such as press workability. The method of the present invention includes rolling a magnesium alloy blank with a reduction roll. The rolling includes controlled rolling performed under the following conditions (1) and (2) wherein M (% by mass) is the Al content in a magnesium alloy constituting the blank: (1) the surface temperature Tb (° C.) of the magnesium alloy blank immediately before insertion into the reduction roll satisfies the following expression: 8.33×M+135?Tb?8.33×M+165 wherein 1.0?M?10.0; and (2) the surface temperature Tr of the reduction roll is 150° C. to 180° C.

Abstract: The invention offers a magnesium alloy sheet material having excellent plastic processibility and rigidity and a magnesium alloy formed body having excellent rigidity. The sheet material has magnesium alloy that forms the matrix containing hard particles. The region from the surface of the sheet material to a position away from the surface by 40% of the thickness of the sheet material is defined as the surface region, and the remaining region as the center region. Hard particles existing in the center region have a maximum diameter of more than 20 ?m and less than 50 ?m, and hard particles existing in the surface region have a maximum diameter of 20 ?m or less. Because the hard particles existing at the surface side are fine particles, they are less likely to become the starting point of cracking or another defect at the time of plastic processing. Because the hard particles existing in the center region are coarse, they can increase the rigidity of the sheet material.

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: Provided is a high-strength stainless steel spring exhibiting a good workability and having a high load characteristic. Thus, the high-strength stainless steel spring of the invention has an chemical component containing 0.04 to 0.08% by mass of C, 0.15 to 0.22% by mass of N, 0.3 to 2.0% by mass of Si, 0.5 to 3.0% by mass of Mn, 16 to 20% by mass of Cr, 8.0 to 10.5% by mass of Ni, 0.5 to 3.0% by mass of Mo, and the balance of Fe and inevitable impurities, and when the average diameter of the coil is represented by D and further the diameter of the steel wire is represented by d in the case that cross sections of the stainless steel wire are in a complete round form or the value obtained by subtracting the average coil diameter from the outer diameter of the coil is represented by d? in the case that the cross sections of the stainless steel wire are in a form other than the complete round form, the spring has a spring index D/d or D/d? of 2 to 6.

Abstract: An oil-tempered wire that has high fatigue strength and toughness after the nitriding treatment, and a method of producing the same, and a spring using the oil-tempered wire are provided. The oil-tempered wire has a tempered martensite structure. A lattice constant of a nitride layer formed on a surface of the wire is 2.870 ? to 2.890 ? when the oil-tempered wire is nitrided. The oil-tempered wire is produced by wire drawing a steel wire and quenching and tempering the wire drawn steel wire. The quenching is performed after the radiation heating is performed at 850 to 950° C. for over 30 sec to 150 sec, and the tempering is performed at 400 to 600° C.

Abstract: Provided is a high-strength stainless steel spring exhibiting a good workability and having a high load characteristic. Thus, the high-strength stainless steel spring of the invention has an chemical component containing 0.04 to 0.08% by mass of C, 0.15 to 0.22% by mass of N, 0.3 to 2.0% by mass of Si, 0.5 to 3.0% by mass of Mn, 16 to 20% by mass of Cr, 8.0 to 10.5% by mass of Ni, 0.5 to 3.0% by mass of Mo, and the balance of Fe and inevitable impurities, and when the average diameter of the coil is represented by D and further the diameter of the steel wire is represented by d in the case that cross sections of the stainless steel wire are in a complete round form or the value obtained by subtracting the average coil diameter from the outer diameter of the coil is represented by d? in the case that the cross sections of the stainless steel wire are in a form other than the complete round form, the spring has a spring index D/d or D/d? of 2 to 6.

Abstract: A wire-harness use composite wire comprising a first element wire which comprises 0.01-0.25 mass % C, 0.01-0.25 mass % N, 0.5-4.0 mass % Mn, 16-20 mass % Cr,8.0-14.0 mass % Ni, and the balance of Fe and impurities and satisfies that a C+N content is in the range of 0.15 mass %?C+N?0.30 mass %, and a second element wire comprising at least one material selected from the group consisting of copper, copper alloy, aluminum, and aluminum alloy, the first element wire and the second element wire being twisted together.

Abstract: It is an object of the invention to provide a magnesium welding wire excellent in surface cleanliness and a method for manufacturing the same. A welding wire according to the invention can be manufactured by drawing a base material such as an extruded material made of pure magnesium or a magnesium-based alloy and, after then, by shaving the surface of the thus drawn wire. Execution of the shaving operation makes it possible not only to effectively remove a lubricant and a coating used in the drawing operation but also to effectively remove an oxide generated during the drawing operation. Thanks to this, the thus obtained welding wire is excellent in surface cleanliness. As a lubricant to be used in the drawing operation, preferably, there may be used an oil lubricant or a wet-type lubricant which can be removed easily by a cleaning operation or by a grease removing treatment.

Abstract: A magnesium base alloy pipe having high strength and toughness is provided along with a method of manufacturing such pipes. A magnesium base alloy pipe, wherein the pipe is produced by drawing a pipe blank of a magnesium base alloy comprising containing either of the following ingredients (1) or (2): (1) about 0.1-12.0 mass % of Al; or (2) about 1.0-10.0 mass % of Zn and about 0.1-2.0 mass % of Zr. The novel alloy pipe is manufactured by a method comprising steps of providing the above-described pipe blank, pointing the pipe blank, and drawing the pointed pipe blank. The drawing step is executed at a drawing temperature above approx. 50° C.

Abstract: The present invention provides a method for producing a magnesium alloy sheet capable of producing a magnesium alloy sheet having excellent plastic workability such as press workability. The method of the present invention includes rolling a magnesium alloy blank with a reduction roll. The rolling includes controlled rolling performed under the following conditions (1) and (2) wherein M (% by mass) is the Al content in a magnesium alloy constituting the blank: (1) the surface temperature Tb (° C.) of the magnesium alloy blank immediately before insertion into the reduction roll satisfies the following expression: 8.33×M+135?Tb?8.33×M+165 wherein 1.0?M?10.0; and (2) the surface temperature Tr of the reduction roll is 150° C. to 180° C.

Abstract: The present invention provides a spring steel wire which has a tempered martensitic structure brought about by quenching-tempering. The present spring steel wire has a 40% or higher reduction of area and a 1,000 MPa or higher shear yield stress after subjected to heat treatment for at least hours at a temperature ranging from 420° C. to 480° C. The present steel wire preferably constitutes, based on mass %, C: 0.50-0.75%, Si: 1.80-2.70%, Mn: 0.1-0.7%, Cr: 0.70-1.50%, Co: 0.02-1.00%, and remnants consisting of Fe and impurities, or constitutes, based on mass %, C: 0.50-0.75%, Si: 1.80-2.70%, Mn: over 0.7-1.50%, Cr: 0.70-1.50%, and remnants consisting of Fe and impurities.

Abstract: A high-strength steel wire for heat-resistant springs has both excellent high-temperature tensile strength and excellent high-temperature sag resistance at a temperature as high as 350 to 500° C., particularly at 400° C. or so (these properties are needed for spring materials). The steel wire contains (a) 0.01 to 0.08 wt % C, 0.18 to 0.25 wt % N, 0.5 to 4.0 wt % Mn, 16 to 20 wt % Cr, and 8.0 to 10.5 wt % Ni, (b) at least one constituent selected from the group consisting of 0.1 to 3.0 wt % Mo, 0.1 to 2.0 wt % Nb, 0.1 to 2.0 wt % Ti and 0.3 to 2.0 wt % Si, and (c) mainly Fe and unavoidable impurities both of which constitute the remainder. The steel wire has (a) a tensile strength of at least 1,300 N/mm2 and less than 2,000 N/mm2 before being treated with low-temperature annealing, and (b) a maximum crystal-grain diameter of less than 12 ?m in the ? phase (austenite) in a transverse cross section of the wire.

Abstract: [Object] To provide a wire-harness use composite wire having a further improved corrosion resistance, while having excellent conductivity and strength. [Solving means] A wire-harness use composite wire comprising a first element wire which comprises 0.01-0.25 mass % C, 0.01-0.25 mass % N, 0.5-4.0 mass % Mn, 16-20 mass % Cr, 8.0-14.0 mass % Ni, and the balance of Fe and impurities and satisfies that a C+N content is in the range of 0.15 mass %?C+N?0.30 mass %, and a second element wire comprising at least one material selected from the group consisting of copper, copper alloy, aluminum, and aluminum alloy, the first element wire and the second element wire being twisted together.

Abstract: A steel wire of pearlite structure containing 0.8-1.0 mass % of C and 0.8-1.5 mass % of Si is disclosed. In the cross section of the steel wire the difference in average hardness between a region up to 100 ?m from the surface thereof and a deeper region is within 50 in micro-Vickers hardness. The steel wire is manufactured by working a wire rod having the abovementioned chemical composition through shaving, patenting and drawing processes, then strain-relief annealing the resultant wire, and thereafter subjecting the thus annealed to a shot peening process. The steel wire has a high heat resistance and a high fatigue strength, and can be produced through a drawing process without applying a quenching and tempering process.