An All-Atom Simulation Study of Gas Detonation Forming Technique

Abstract

The high-speed forming process is the key to attaining difficult and irregular profiles on ductile materials. In the present work, we proposed the all-atom model of the gas detonation forming process, wherein molecular dynamics (MD) simulations were performed on the aluminum workpiece at different loading speeds similar to the various pressure values in the process. The deformation response of an aluminum workpiece for a wide range of loading speeds, 0.1–8 Å/ps, was investigated. The dome-height, failure patterns, and formability of the aluminum workpiece were examined for these loading speeds. We obtained an inverse relationship between the formability of the aluminum workpiece and the applied loading speed. Moreover, in this work, the influence of the different percentage of defects in the workpieces on the mechanical behavior was investigated. We observed that at lower speeds (< 2 Å/ps), the deformation is observed throughout the workpiece starting from the point of contact in the middle and that is contrary to the deformations observed due to the higher loading speed where localized deformations occur due to creation of slipping planes. We also found that the internal voids lead to the rearrangement of atoms to facilitate the movement of slipping planes leading to better formability compared to the no-void workpieces. This work helps to get a fundamental understanding of deformation behavior in the high-speed forming process with and without defects in the aluminum workpiece at the nanoscale.