Аннотация:In this paper, we develop a phase field model for microstructure evolution in
laser powder-bed additive manufacturing processes, which allows for the effect of elastic
stresses due to diffusion of atomic defects (vacancy and interstitial atom) generated at the
moving liquid-solid interface. The governing equations of the model including a timedependent Ginsburg-Landau equation for the phase field with additional stress term, a
diffusion-drift Cahn–Hilliard like equation describing atomic defect dynamics, an energy
balance equation for the temperature change, and finally the mechanical equilibrium equation
for the elastic displacement fields are derived within a thermodynamic framework based
on entropy generation guaranteeing thermodynamic consistency. The most simple 1D
and isothermal equilibrium situation is considered to study phenomenon of diffusionflexural instability with the atomic defect clustering and periodic distributions of defects.
The effect of this instability on the exfoliation of deposited thin layers on a substrate is also
discussed.