Multi-Scale Modelling of the Bound Metal Deposition Manufacturing of Ti6Al4V

Abstract

Nonlinear shrinkage of the metal part during manufacturing by bound metal deposition, both on the ground and under microgravity, is considered. A multi-scale physics-based approach is developed to address the problem. It spans timescales from atomistic dynamics on the order of nanoseconds to full-part shrinkage on the order of hours. This approach enables estimation of the key parameters of the problem, including the widths of grain boundaries, the coefficient of surface diffusion, the initial redistribution of particles during the debinding stage, the evolution of the microstructure from round particles to densely-packed grains, the corresponding changes in the total and chemical free energies, and the sintering stress. The method has been used to predict shrinkage at the levels of two particles, of the filament cross-section, of the sub-model, and of the whole green, brown, and metal parts.

Editorial Special Issue on Feature Papers of Thermo in 2022

“…A multiscale modeling approach for predicting the nonlinear shrinkage of metal parts during manufacturing by bound metal deposition was proposed by D.G. Luchinsky et al [8] This article provides deep physical insight into not only the associated mechanisms but also mutual connections between scales by exploring simulation data moving from atomic dynamics to finite element models.…”