A method for producing partially hardened steel components in which a blank composed of a hardenable sheet steel is subjected to a temperature increase and shaped into a component; the component is transferred to a tool in which the heated component is cooled and thus quench hardened; during the heating of the blank or component in order to achieve the temperature increase to a temperature required for the hardening in regions that are to have a lower hardness and/or higher ductility, cooling elements are spaced apart from the surface by a small gap; the cooling element is dimensioned so that the thermal energy acting on the region that remains ductile flows through the component into the cooling element, characterized in that in order to space the cooling element apart from the component, micro-nubs or knobs are used, which are distributed over the area of the cooling element.

A method to produce a molded part having at least two regions of different strength using a press-hardening tool. A heated blank is formed in the tool during a forming step and held therein for heat-treating during a cooling step. At least one region of lower strength is cooled more slowly than at least one region of higher strength. During the forming step, the entire blank is in contact with a molding surface of the tool. Then, the tool surface is changed such that one or more regions of lower strength have no tool contact during the cooling step. The tool surface associated with the one or more regions of lower strength is provided by tool segments that are adjustable relative to the remaining tool surface. The molding surface of the one or more tool segments is larger than the region of lower strength associated with such tool segment.

A formed and hardened component made from a metallic material is post-treated by a device for electric resistance heating that has at least one first pair of contact pieces and at least one second pair of contact pieces; contacting a first partial region of the component with the contact pieces of the first pair such that the first partial region is arranged between the contact pieces of the first pair; contacting the second partial region of the component with the contact pieces of the second pair such that the second partial region is arranged between the contact pieces of the second pair; heating of the first partial region of the component to a first temperature by conducting electric current through the component by the first pair of contact pieces; setting the second partial region of the component to a second temperature by the second pair of contact pieces, which is set independently of the first temperature.

The present invention relates to a method and an apparatus for treating already galvanized steel parts having a zinc coating, in particular for remanufacturing used galvanized steel parts. The method comprises the following steps: A) checking the galvanized steel part for suitability with a view to remanufacturing; B) preparing the galvanized steel part mechanically and/or chemically; and C) rejuvenating the zinc coating of the steel part.

The present disclosure relates to a system for manufacturing a hybrid component including a first thermal supplier configured to heat a steel plate, a rolling roll for undercut configured to pressurize the steel plate heated by the first thermal supplier, and to form an undercut on one surface of the steel plate, a first molding roll configured to pressurize the steel plate formed with the undercut to mold the steel plate in a shape of a component to be manufactured, a composite material feeder configured to supply a composite material tape to be seated on one surface of the steel plate formed with the undercut through the first molding roll, and a composite material pressurization roll configured to pressurize the steel plate on which the composite material tape is seated.

A vehicle underbody assembly including a pair of rockers, a pair of side rails, a first cross member, a second cross member, and a fuel tank is provided. Each of the pair of side rails is secured to a rearward portion of one of the rockers. The first cross member extends between the side rails and is thermally treated to form a first central hard strength zone between two first soft strength zones. The second cross member is arranged with the pair of side rails and the first cross member to form a rectilinear frame and is thermally treated to form a second central hard strength zone between two second soft strength zones. The fuel tank is secured between the pair of side rails so that the fuel tank is located within a rectilinear frame formed by the pair of side rails and the cross members.

A vehicle underbody assembly including a pair of rockers, a pair of rear rails, a first cross member, and a second cross member is provided. Each of the pair or rear rails extends from one of the rockers and each includes a rear portion, a first mid-portion, a second mid-portion, and a forward portion. Each of the forward portions is secured to one of the rockers at one of a first joint and a second joint. The first cross member extends between the rear rails at a transition region between the second mid-portion and the forward portion. The second cross member extends between the rear rails at locations adjacent the first and second joints. Each of the rear rails is thermally treated so that the second mid-portions form a hard strength zone. The hard strength zone may further be defined as a zone having a fully martensitic microstructure.

A bumper assembly may include a pair of crush cans and a bumper beam. The pair of crush cans are for securing to a vehicle body. The bumper beam is secured to the crush cans and includes a first end and a second end each extending outboard of one of the crush cans, and a middle portion extending between the first and second ends. The bumper beam is thermally treated to provide the first and second ends with less tensile strength than the middle portion. The middle portion may have a tensile strength between 1000 MPa and 1900 MPa. Each of the first and second ends may have a tensile strength between 600 MPa and 900 MPa.

In an austenitic stainless steel sheet, the arithmetic average roughness Ra is 0.2 ?m or more and 1.2 ?m or less. In addition, the dull pattern transfer rate on the steel sheet surface is 15% or more and 70% or less. Furthermore, micropits with a depth of 0.5 ?m or more and an open area of 10 ?m.sup.2 or more which are formed on the steel sheet surface have an existing density of 10.0 or less per 0.01 mm.sup.2 and an open area ratio of 1.0% or less. In addition, a film formed on the steel sheet surface is constituted from an oxide containing SiO.sub.2 as a main constituent, which oxide contains at least Si, N, Al, Mn, Cr, Fe, Nb, Ti and O as film-forming elements other than C, wherein the Si content is 10 at % or more, and the N content is 10 at % or less.

A die apparatus including a first die element, a plurality of second die elements, a plurality of actuators, and a controller is provided. Each of the plurality of actuators is mounted to one of the plurality of second die elements. The controller is programmed to activate the actuators to contact and compress portions of a blank disposed between the die elements at separate pressures to influence microstructure forming for one of a geometry transition region, a deformation region, and a joining region. One of the separate pressures applied to one of the portions of the blank may be approximately 5 N/mm.sup.2 or less to form a soft strength zone. The pressure of approximately 5 N/mm.sup.2 or less may be applied to the one of the portions of the blank for approximately one to two seconds.