METHOD FOR PRODUCING WHEEL DISCS FROM A DUAL-PHASE STEEL WITH IMPROVED COLD WORKABILITY

摘要

The invention relates to a method for producing a wheel disc from a dual-phase steel, having improved cold workability of cold-solidified, mechanically separated sheet metal edges, comprising the following method steps: - providing a hot-rolled strip or a hot-rolled strip sheet of the claimed alloy composition having a dual phase structure, consisting of a ferritic matrix, into which a predominantly martensitic second phase is embedded in an insular manner, - cutting a sheet at room temperature and optionally carrying out further punching or cutting operations, - heating exclusively the sheet metal edge regions of the blank, which have been cold-solidified by the cutting or punching operations, to a temperature of at least 700 °C with a dwell time of at most 10 seconds and subsequent cooling with air, and - cold forming the blank in one or more steps to form a wheel disc at room temperature.