Abstract
A substantial amount of testing and analysis was performed over the 41 month-duration of this
Cooperative Research and Development Agreement (CRADA) between Vehma International (herein
referred to as Vehma) and the Oak Ridge National Laboratory (ORNL). ORNL's work focused on
supporting the further development of Vehma’s overcast technology. This effort characterized and
modeled the residual stresses present in the Al/steel bi-metallic joints before and after heat treatment and
demonstrated feasibility of a novel T6 heat treatment of these joints with a prototype IR furnace. This
work will enable Vehma and other Tier I automotive suppliers improved weight reduction in automotive
assemblies, which help to meet Lightweighting & VT goals. Engine cradles, incorporating the overcast
technology, have subsequently been validated by an OEM for durability, corrosion and crash
performance.
