The impact welding is gaining popularity in joining of dissimilar metals as any intermetallics are
often very thin or discontinous with little to no heat affected zone resulting from the process. This
work focuses on a recently developed impact welding technique, known as the Vaporizing Foil Actuator
Welding (VFAW), which uses the pressure created from the electrically driven rapid vaporization
of a thin metallic conductor to drive the flyer. A typical characteristic of an impact-welded joint is
the wavy weld interface which is attributed to the complex interfacial kinematics resulting from the
high-speed oblique impact of the metal plates. A numerical simulation framework based on the finite
element method (FEM) with Eulerian formalism is developed to model the high-speed impact between
the metal plates. The model accounts for the thermomechanical interactions in the process and captures
the complex interfacial deformations. A thorough validation of the model is achieved by comparing the
wave characteristics obtained from numerical simulations with the experimental results from vaporizing
foil actuator welding. The amplitude and wavelength of the interfacial waves and the resulting joint
microstructure is shown to be strongly dependent on the process conditions and the specific material
system, which is well captured by the model.
Revised: January 11, 2019 |
Published: February 1, 2019
Citation
Gupta V., T. Lee, A. Vivek, K. Choi, Y. Mao, X. Sun, and G. Daehn. 2019.A robust process-structure model for predicting the joint interface structure in impact welding.Journal of Materials Processing Technology 264.PNNL-SA-132656.doi:10.1016/j.jmatprotec.2018.08.047