Abstract: A method for manufacturing an ultra-high-tensile sheet method product of steel, at which the initial work piece used is constituted of a metal work piece of iron, alloyed with chromium, nickel and carbon in predetermined proportions. The initial work piece is wholly or partially plastically cold worked by stretch forming or stretch bending at a predetermined temperature and/or deformation degree, that determines and is determining for the yield point of the final product, in providing a strong deformation hardening, that gives the final product a totally or partially many times increased strength or higher yield point, as compared to the yield point of the initial work piece.

Abstract: The invention relates to workpiece control shaping of metal, preferably in the form of plates or bands, which metal workpiece has a high tensile limit, preferably about 1000 N/mm2, and is intended to be further shaped. Along predetermined folding notches or zones across the workpiece, the tensile limit of the material is reduced by heating to a tensile limit, which is substantially lower than that of adjacent base material, and when the workpiece has cooled it is subjected to subsequent bending, folding, or shaping operations to provide a two- or three-dimensional shape/extension of the workpiece along the treated folding notches or zones.

Abstract: The invention relates to a method and device for manufacturing a closed profile in a profile structure and a closed profile manufactured according to the method. The closed profile used and constituted by a metal material of iron, alloyed with chromium, nickel and carbon in predetermined proportions is plastically formed, wherein a strong strain hardening of the closed profile is obtained.

Abstract: The invention relates to workpiece control shaping of metal, preferably in the form of plates or bands, which metal workpiece (1) has a high tensile limit, preferably above 1000 N/MM2 and is intended to be further shaped. Along predetermined folding notches or zones (2, 3) across the workpiece (1) the tensile limit of the material is reduced by heating to a tensile limit, which is substantially lower than that of adjacent base material, whereafter the workpiece (1) directly or when it has got cold is subjected to subsequent bending, folding- or shaping operations to provide a two- or three-dimensional shape/extension of the workpiece (1 along the treated folding notches or zones (2, 3).