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In this work, a process-structure-property relationship for additively manufactured Al-Si-Mg alloy was constructed, with the aid of an integrated multi-physics model. Specifically, first, a series of thermal simulations were performed to understand molten pool geometry under different additive manufacturing (AM) operating conditions, including laser beam power, scanning speed, and hatch spacing. The porosity formation was predicted based on thermal simulation results, which yield molten pool dimension information for predicting the lack-of-fusion porosity. Dream.3D was utilized to reconstruct synthetic microstructures with different volume fraction of porosity.

This paper presents a computational study to investigate effects of crystal orientations on plasticity and damage of copper crystal at atomic scale. In the present study, a single crystal copper model was created as a target, which was struck and penetrated by a single crystal nickel. Three orientations, single slip system [1 0 1, 1 2 -1, -1 1 1], double slip system [1 1 2, 1 1 0, 1 1 -1], and octal slip system [1 0 0, 0 1 0, 0 0 1], were applied to the copper crystal. Their effects on plasticity and damage behavior of the single crystal copper were studied and compared using molecular dynamics simulations. Modified Embedded Atom Method potentials were applied to determine the pair interactions between the copper and nickel atoms.

A common interaction between a penetrator and a target has been the use of copper and nickel materials. However, a multiscale analysis has not been performed on such a system. Compared to steels, aluminum alloys, titanium alloys and other metallic materials, a description of the mechanical behavior of pure ductile metals such as Cu struck by a penetrator comprises nickel under the high strain rate at different multiscale still remains unknown. In this research, Modified Embedded Atom Method (MEAM) Potential is utilized to study this system and the molecular dynamics simulation is employed in order to provide structure property evolution information for plasticity and shearing mechanisms.