1. Introduction
Automakers around the world have focused their efforts on developing cars with lightweight structures to reduce
the energy consumption and environmental impact of vehicles. In 1964 the concept of tailor welded blank (TWB) was
introduced to the automotive industry, as a new way of manufacturing body panels, in order to reduce the weight of
structures and improve the body stiffness (Ono et al. 2004), (Eva et al. 2012). TWBs enable designers to include
different sheets of different thicknesses and material characteristics into one part, prior to forming, to optimize their