A patch is a piece of steel which is welded directly to a ‘mother’ blank before stamping. The steel grade and/or the thickness of the patch can differ from that of the mother blank.
Using a patch enables OEMs to tailor a specific area of a final component. For example, a patched blank can cost-effectively improve a vehicle’s crash performance.
Patched blanks are ideal for managing energy absorption and are already helping automakers to meet crash test requirements.
Patched blanks provide a localised solution to improve the behaviour of a part and avoid the risk of failure. By using a patch made from a different grade or thickness to the mother blank, the properties of the final assembly can be tailored very precisely.
That gives OEMs a high degree of flexibility. For example, patches of different grades or thicknesses can be used for different versions of a vehicle. In this way, OEMs can use the same part design for a battery electric version and a plug-in hybrid version of the same vehicle.
Using patches also enables OEMs to reduce the number of tools required. The nesting of blanks for different vehicles models can be optimised using the same cutting die.
The total cost of the part is reduced significantly thanks to these advantages. As the stamping operation is done in just one stroke for both the part and reinforcement, cycle time is also reduced.
Patched blanks provide flexible solutions for all types of vehicles, particularly when they are combined with laser welded blanks.
ArcelorMittal has built a new patch line at its Tailored Blanks plant in Liège (Belgium) to make patch technology more widely available to the global automotive industry. The line can handle almost all automotive steels including ArcelorMittal’s latest press hardenable steels (PHS). This enlarges the portfolio of options ArcelorMittal Tailored Blanks can offer OEMs, ensuring we are ready to meet the automotive industry challenges ahead.
Watch the video to see how the new patch line works: