Tailor-Welded Blanks

            Tailor-welded blank sounds like an insult that might be pitched at a dim–witted male model, but TWBs have become an important part of making cars stronger and lighter.

            A TWB is a pressed part made from two sheets of metal of different thicknesses. The sheets are laser welded together edge-to-edge to ensure a strong and smooth joint before being pressed into shape.

            The advantage of TWBs over plain sheet pressed parts is they can concentrate thicker and stronger metal where it is needed and this allows the use of thinner metal for less critical sections to save weight. Parts where strength in a crash is vital, such as engine mounting rails, floor pans, windscreen pillars and door openings, are made from TWBs in most new cars.

            Special care has to be taken in the press to avoid stressing or distorting the weld line between the two sheets.