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Vaporizing Foil Actuators (VFA) are based on the phenomenon of rapid vaporization of thin metallic foils and wires, caused by passage of a capacitor bank driven current on the order of 100 kA. The burst of the conductor is accompanied with a high-pressure pulse, which can be used for working metal at high strain rates. This paper focuses on the use of VFA for collision welding of dissimilar metals, in particular, aluminum and steel. Aluminum alloy 6061 sheets of 1 mm thickness were launched to velocities in excess of 650 m/s with input electrical energy of 8 kJ into 0.0762 mm thick, dog-bone shaped aluminum foil actuators. Target sheets made from dual phase steel (DP780) were impacted with the aluminum flyer sheet, and solid state impact welds were created. During mechanical testing, many samples failed outside the weld area, thereby indicating that the weld was stronger than the parent aluminum.

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.