A high-strength steel sheet has a chemical composition including 0.05% to 0.3% of C, 1% to 3% of Si, 0.5% to 3% of Mn, 0% to 0.1% of P, 0.001% to 0.1% of Al, and 0.002% to 0.03% of N, in mass percent; further includes iron and impurities; and has a structure including 50% to 90% of bainitic ferrite, 5% to 20% of retained austenite (.sub.R), a total of 10% to 50% of martensite and the retained austenite, and 0% to 40% of polygonal ferrite, in area percent based on the entire structure. The retained austenite has a carbon content (C.sub.R) of 0.5% to 1.2% by mass, an average equivalent circle diameter of 0.2 to 2 m, and an average aspect ratio (maximum diameter/minimum diameter) of less than 3.0. The high-strength steel sheet excels both in elongation and deep drawability while having a strength of 980 MPa or more.

The present invention relates to a torsional severe plastic deformation method for a metal bar to which surface polishing is applied to the metal bar to improve the mechanical properties of the metal bar. According to an embodiment of the present invention, there is provided a torsional severe plastic deformation method for a metal bar, which includes: applying torsion to a metal bar; and removing a surface defect on the surface of the metal bar, the surface defect being caused by the applying of torsion, wherein the removing of the surface defect is carried out in a continuous manner in which the removing of the surface defect is performed together with the applying of torsion or in a discontinuous manner in which the applying of torsion is temporarily stopped and then the applying of torsion is performed, and the removing of a surface defect increases the amount of torsional rotation or the shear strain applied to the metal bar.

The present invention relates to a torsional severe plastic deformation method for a metal bar to which surface polishing is applied to the metal bar to improve the mechanical properties of the metal bar. According to an embodiment of the present invention, there is provided a torsional severe plastic deformation method for a metal bar, which includes: applying torsion to a metal bar; and removing a surface defect on the surface of the metal bar, the surface defect being caused by the applying of torsion, wherein the removing of the surface defect is carried out in a continuous manner in which the removing of the surface defect is performed together with the applying of torsion or in a discontinuous manner in which the applying of torsion is temporarily stopped and then the applying of torsion is performed, and the removing of a surface defect increases the amount of torsional rotation or the shear strain applied to the metal bar.

A bender includes a rotatable bending shoe having a plurality of channels therein configured to receive a workpiece and a follower assembly. The follower assembly includes a mount, a follower bar attached to the mount, the follower bar having a plurality of channels therein configured to receive the workpiece, a roller attached to the mount and engaged against the follower bar, the roller having an eccentric shaft extending therefrom, and a motor for rotating the shaft and roller, wherein rotation of the shaft and roller causes the follower bar to translate toward or away from the bending shoe. A drive member can be provided to move the mount toward or away from the bending shoe.

A cut-to-length line for processing coiled sheet metal having a thickness of greater than 0.200 inches has an uncoiler, a descaler, and flattening machinery which may be a stretcher leveler or a temper mill. The line is operated in an advancement mode by (i) the advancing the sheet metal through the line; and (ii) descaling the sheet metal in the descaler. In one aspect, when a length of sheet metal to be stretch leveled is positioned in the stretcher leveler, the line may be operated in an idle mode by: (i) stopping the advancement of the sheet metal from the uncoiler through the descaler; (ii) stopping descaling of the sheet metal in the descaler; and (iii) stretch leveling the length of the sheet metal. When stretch leveling is complete, the line may be operated in the advancement mode.

A cut-to-length line for processing coiled sheet metal having a thickness of greater than 0.200 inches has an uncoiler, a descaler, and flattening machinery which may be a stretcher leveler or a temper mill. The line is operated in an advancement mode by (i) the advancing the sheet metal through the line; and (ii) descaling the sheet metal in the descaler. In one aspect, when a length of sheet metal to be stretch leveled is positioned in the stretcher leveler, the line may be operated in an idle mode by: (i) stopping the advancement of the sheet metal from the uncoiler through the descaler; (ii) stopping descaling of the sheet metal in the descaler; and (iii) stretch leveling the length of the sheet metal. When stretch leveling is complete, the line may be operated in the advancement mode.

A foil tab forming apparatus forms at least one foil tab of a positive electrode foil tab and a negative electrode foil tab respectively provided at a top portion and a bottom portion of an electrode assembly. The foil tab forming apparatus includes a pre-forming jig configured to bend the foil tab by pressing the foil tab, while moving in a direction from an outer circumferential portion of the electrode assembly to a winding center portion of the electrode assembly and a forming jig configured to press the foil tab that has been primarily bent by the pre-forming jig, by moving along a direction parallel to a winding axis of the electrode assembly.

A foil tab forming apparatus forms at least one foil tab of a positive electrode foil tab and a negative electrode foil tab respectively provided at a top portion and a bottom portion of an electrode assembly. The foil tab forming apparatus includes a pre-forming jig configured to bend the foil tab by pressing the foil tab, while moving in a direction from an outer circumferential portion of the electrode assembly to a winding center portion of the electrode assembly and a forming jig configured to press the foil tab that has been primarily bent by the pre-forming jig, by moving along a direction parallel to a winding axis of the electrode assembly.

A header beam couples between A-pillars of a vehicle frame. The header beam is formed from a generally straight beam segment that is extruded to have a hollow body portion with supportive legs extending within the hollow interior along the length of the beam segment, defining uninterrupted forward and rearward box sections for supporting continuous load paths on the header beam. The end portions of the beam segment are clamped and the beam segment is stretch bent to form a curvature between the end portions that remain generally straight. A front flange extends forward along the body portion and is struck proximate the end portions to form an edge that is parallel to the curvature formed between the end portions. The end portions are attached to the A-pillars and the edge of the front flange is attached to a windshield.

A header beam couples between A-pillars of a vehicle frame. The header beam is formed from a generally straight beam segment that is extruded to have a hollow body portion with supportive legs extending within the hollow interior along the length of the beam segment, defining uninterrupted forward and rearward box sections for supporting continuous load paths on the header beam. The end portions of the beam segment are clamped and the beam segment is stretch bent to form a curvature between the end portions that remain generally straight. A front flange extends forward along the body portion and is struck proximate the end portions to form an edge that is parallel to the curvature formed between the end portions. The end portions are attached to the A-pillars and the edge of the front flange is attached to a windshield.