Abstract: High strength steel sheet which secures tensile maximum strength 900 MPa or more high strength while having excellent shapeability, which high strength steel sheet which is excellent in shapeability characterized by having a predetermined composition of ingredients, by the steel sheet structure including a ferrite phase and martensite phase, by the ratio of Cu particles incoherent with the bcc iron being 15% or more with respect to the Cu particles as a whole, by a density of Cu particles in the ferrite phase being 1.0×1018/m3 or more, and by an average particle size of Cu particles in the ferrite phase being 2.0 nm or more.

Abstract: Disclosed is a press forming method press forming a workpiece between a die and a punch, while pushing the punch into the die by means of a relative motion of the die and the punch, the method includes: producing an intermediate molding (100B) having ridges (100d) formed in predetermined parts of the workpiece, and then press forming the intermediate molding (100B) into a final shape, to thereby substantially thicken and work-harden the predetermined parts of the workpiece.

Abstract: Disclosed is a press forming method press forming a workpiece between a die and a punch, while pushing the punch into the die by means of a relative motion of the die and the punch, the method includes: producing an intermediate molding (100B) having ridges (100d) formed in predetermined parts of the workpiece, and then press forming the intermediate molding (100B) into a final shape, to thereby substantially thicken and work-harden the predetermined parts of the workpiece.

Abstract: A method for manufacturing a press-formed product includes: a first step of preparing a long material having a bending portion; and a second step of decreasing curvature of the bending portion while restricting both ends of the long material in a longitudinal direction.

Abstract: A bending fracture limit stress is calculated for each of (bend radius at sheet thickness center of a metal sheet)/(initial sheet thickness of the metal sheet); a fracture limit curve and a fracture limit stress are calculated from work hardening characteristics; a fracture limit curve corresponding to (the metal sheet bend radius at sheet thickness center)/(the initial sheet thickness of the metal sheet) is calculated; a corresponding fracture limit stress is calculated from stress of the element subject to determination and the fracture limit curve; a risk ratio that is a ratio between the stress of the element subject to determination and the fracture limit stress is computed; and performing fracture determination for the element subject to determination based on the risk ratio.

Abstract: The present invention provides a high-strength galvanized steel sheet with maximum tensile strength of 900 MPa or more. The high-strength galvanized steel sheet has an alloyed galvanized layer formed on a surface of a base steel sheet containing predetermined amounts of C, Si, Mn, P, S, Al, N, O with a balance being constituted of iron and inevitable impurities, in which in a structure of the base steel sheet, retained austenite is limited to 8% or less in volume fraction, kurtosis K* of the hardness distribution between 2% hardness and 98% hardness is ?0.30 or less, a ratio between Vickers hardness of surface layer of the base steel sheet and Vickers hardness of ¼ thickness of the base steel sheet is 0.35 to 0.70, and a content of iron in the alloyed galvanized layer is 8 to 12% in mass %.

Abstract: A vehicle frame member structure has a closed cross-sectional structure including a pair of first wall portions, and a pair of second wall portions connected to the pair of the first wall portions, in which first beads are provided on the pair of first wall portions along a circumferential direction of the closed cross-sectional structure, a second bead is provided on either of the pair of second wall portions along the closed cross-sectional circumferential direction on a line extending from the first bead in the circumferential direction, the first and second beads are connected in two corner portions between the first wall portions and the second wall portion, a recessed embossed portion is provided in a connection portion of the first and second beads in at least one of the corner portions, and the sheet thickness of the embossed portion is larger than that of the first or second wall portion.

Abstract: A cold-rolled steel sheet containing: in mass %, C: 0.0005 to 0.0045%; Mn: 0.80 to 2.50%; Ti: 0.002 to 0.150%; B: 0.0005 to 0.01%, in which (1) Expression is satisfied, and a balance being composed of iron and impurities, in which at the position of ¼ thickness of a sheet thickness, a random intensity ratio (A) of the {332}<110> orientation is 3 or less, a random intensity ratio (B) of the {557}<9 16 5> orientation and a random intensity ratio (C) of the {111}<112> orientation are both 7 or more, and {(B)/(A) 5} and {(B)>(C)} are satisfied.

Abstract: A vehicle frame member structure has a closed cross-sectional structure including a pair of first wall portions, and a pair of second wall portions connected to the pair of the first wall portions, in which first beads are provided on the pair of first wall portions along a circumferential direction of the closed cross-sectional structure, a second bead is provided on either of the pair of second wall portions along the closed cross-sectional circumferential direction on a line extending from the first bead in the circumferential direction, the first and second beads are connected in two corner portions between the first wall portions and the second wall portion, a recessed embossed portion is provided in a connection portion of the first and second beads in at least one of the corner portions, and the sheet thickness of the embossed portion is larger than that of the first or second wall portion.

Abstract: According to exemplary embodiments of the present invention, using a fracture limit stress line obtained by converting a hole expansion ratio into a stress as a criterion for a fracture, the risk of fracture in a material can be evaluated quantitatively by comparing the relationship between data obtained from a numerical analysis using a finite element method and the fracture limit stress line. Thus, when determining a fracture limit in a stretch flange portion in a thin plate in a process including one or more deformation path variations, it is possible to obtain the fracture limit curve easily and efficiently and predict the fracture with high accuracy, and the risk of fracture upon press forming or crash can be evaluated.

Abstract: The present invention provides a press forming simulation method using a finite element method for a sheet metal, in which a deformation state of a pressing tool is represented with high accuracy by superimposing at least one natural mode, for the surface shape of the pressing tool, in a no-load state.

Abstract: There are provided a paper conveying apparatus which can drive paper set guides, paper feed rollers, retard rollers, and conveyor rollers by a single motor. The paper conveying apparatus includes a paper set guide for setting paper, a paper feed roller for feeding paper set at the paper set guide, a retard roller arranged facing the paper feed roller, a conveyor roller for further conveying paper fed by the paper feed roller, a motor for generating a drive force for driving the paper set guide, and a transmission mechanism, arranged straddling a transport path of the paper, for transmitting the drive force to the paper feed roller and the retard roller, wherein the conveyor roller is driven by the transmission mechanism.

Abstract: The present invention provides a high-strength galvanized steel sheet with maximum tensile strength of 900 MPa or more. The high-strength galvanized steel sheet has an alloyed galvanized layer formed on a surface of a base steel sheet containing predetermined amounts of C, Si, Mn, P, S, Al, N, O with a balance being constituted of iron and inevitable impurities, in which in a structure of the base steel sheet, retained austenite is limited to 8% or less in volume fraction, kurtosis K* of the hardness distribution between 2% hardness and 98% hardness is ?0.30 or less, a ratio between Vickers hardness of surface layer of the base steel sheet and Vickers hardness of ¼ thickness of the base steel sheet is 0.35 to 0.70, and a content of iron in the alloyed galvanized layer is 8 to 12% in mass %.

Abstract: A metallic hollow columnar member with a polygonal cross-section having at least five vertices and sides extending between the vertices, is disclosed. The polygonal cross-section is divided by two vertices (A, B) with small inside angles into two perimeter segments with a perimeter comprising one or more sides, and at least one of the two perimeter segments contains at least four sides. The respective inside angles of at least three vertices (V(i)) included in the perimeter segment which includes the at least four sides are equal to or less than 180°, the distance (SS(i)) between each of the at least three vertices (V(i)) and a straight line (L) connecting the two vertices (A, B) is shorter than ½ of the distance between the two vertices (A, B), and the inside angle of the vertex (C) with the smallest inside angle among the at least three vertices (V(i)) is larger than the inside angles of the two vertices (A, B).

Abstract: There are provided a paper conveying apparatus that can prevent a drop in quality of the image data while enabling stable conveyance of paper. The paper conveying apparatus includes a first image capture unit, a second image capture unit, a pair of conveyor rollers including a first roller and a second roller, a first conveyor guide, and a second conveyor guide, wherein a nip position of the pair of conveyor rollers is arranged above an extended plane of a top surface of the first image capture unit extended to the pair of conveyor rollers side, an axis of rotation of the second roller is arranged offset to the first image capture unit side compared with an axis of rotation of the first roller at projections on the extended plane, and the first conveyor guide guides the medium conveyed to above from the extended plane, to make the medium turn downward.

Abstract: Disclosed is a press forming method press forming a workpiece between a die and a punch, while pushing the punch into the die by means of a relative motion of the die and the punch, the method includes: producing an intermediate molding (100B) having ridges (100d) formed in predetermined parts of the workpiece, and then press forming the intermediate molding (100B) into a final shape, to thereby substantially thicken and work-harden the predetermined parts of the workpiece.

Abstract: High strength steel sheet which secures tensile maximum strength 900 MPa or more high strength while having excellent shapeability, which high strength steel sheet which is excellent in shapeability characterized by having a predetermined composition of ingredients, by the steel sheet structure including a ferrite phase and martensite phase, by the ratio of Cu particles incoherent with the bcc iron being 15% or more with respect to the Cu particles as a whole, by a density of Cu particles in the ferrite phase being 1.0×1018/m3 or more, and by an average particle size of Cu particles in the ferrite phase being 2.0 nm or more.

Abstract: There are provided a paper conveying apparatus that can prevent a drop in quality of the image data while enabling stable conveyance of paper. The paper conveying apparatus includes a first image capture unit, a second image capture unit, a pair of conveyor rollers including a first roller and a second roller, a first conveyor guide, and a second conveyor guide, wherein a nip position of the pair of conveyor rollers is arranged above an extended plane of a top surface of the first image capture unit extended to the pair of conveyor rollers side, an axis of rotation of the second roller is arranged offset to the first image capture unit side compared with an axis of rotation of the first roller at projections on the extended plane, and the first conveyor guide guides the medium conveyed to above from the extended plane, to make the medium turn downward.

Abstract: There are provided a paper conveying apparatus which can drive paper set guides, paper feed rollers, retard rollers, and conveyor rollers by a single motor. The paper conveying apparatus includes a paper set guide for setting paper, a paper feed roller for feeding paper set at the paper set guide, a retard roller arranged facing the paper feed roller, a conveyor roller for further conveying paper fed by the paper feed roller, a motor for generating a drive force for driving the paper set guide, and a transmission mechanism, arranged straddling a transport path of the paper, for transmitting the drive force to the paper feed roller and the retard roller, wherein the conveyor roller is driven by the transmission mechanism.