Tailored Closed Sections for Seat Structures - Effect of Stress Risers

Tailored closed sections were created by Orbital Laser Welding tube sections from round steel tubes with differing thicknesses (1 mm wall joined to a 2 mm wall). The tubes were 38 mm outer diameter and constructed from high strength low alloy (HSLA) steel (E235 +c; 10308 per EN10305-1). The tailored closed sections were subjected to compressive and torsion loading conditions to assess the strength of the Orbital Laser Weld. The Orbital Laser Weld was found to have higher strength than the base materials and the performance of the tailored closed section was limited by the thinner section of tube. Results of this study enable automotive seating structures to be optimized for performance while minimizing mass and cost.