Patent ID: 6772499
Filing Date: 2004-08-10
Classification: B21B,B21K,B23P,Y10T

Abstract:
A method of producing a metal section, said method comprising the steps of:making a groove in a first section limb by microstructure-changing material deformation, whereby the degree of deformation is chosen in such a way that the material at least in a deformation zone below the groove is at least partially work-hardened in comparison with remaining material of the first section limb, providing an insertion depth region of a second section limb that is adapted for insertion into said groove in said first section limb and then treating said insertion depth region of said second section limb by microstructure-changing material deformation to increase frictional resistance of said insertion depth region with said groove in said first section limb; positioning said insertion depth region of said second section limb in the groove situated on an inside portion of the first section limb; and applying a pressure at which a flow limit of material situated on both sides of the groove is exceeded, further changing the microstructure of the material in the region near the groove and causing said material situated in said region near the groove of the first section limb to move toward at least one side of the second section limb to such an extent that at least a force fitting joint and a form fitting joint are achieved at substantially all contact locations, said force fitting joint being enhanced by the increased frictional resistance provided by the microstructure-changing material deformation of said insertion depth region of said second section limb section.