Tube hydroforming is nowadays widely used in automotive and aircraft industries. The technology presents strong advantages when compared to conventional stamping forming. Some of them include: less parts in process and, therefore, less operations and lower costs; the use of more complex geometries, with implications on reducing weight and increasing mechanical properties; the need for fewer secondary operations; the obtaining of reduced dimensional variations; better surface finish due to the reduced friction and, finally, reduced scrap [
]. Nevertheless, the process also has some disadvantages, such as: the larger cycle time for some components; the need for relatively expensive equipment and the lack of extensive knowledge base for both process and tool designs. In this sense, the use of a reliable computational-based design tool can be highly desirable. Tailor-welded blank processes, on the other hand, consist on two or more sheets that have been welded together in a single plane prior to forming [
]. The sheets can be identical or, alternatively, can have different thickness, mechanical properties or surface coatings, leading to a versatile production process, from the mechanical properties standpoint. This type of blanks has several advantages, namely the low cost; the reduction in part weight and the flexibility in mass production. Numerical investigations of tubular hydroforming processes, starting from tailor-welded tubes based on one butt welded joint, have been carried out [
]. The need to understand this process, mainly to reduce simulation time and to accurately predict the process, leads to the present study. For this purpose, using solid-shell finite elements [
], the inclusion of the geometry of the weld line will be studied.