  In recent years, liquid metal dealloying (LMD) has emerged as a promising
material processing method to generate micro and nano-scale bicontinuous or
porous structures. Most previous studies focused on the experimental
characterization of the dealloying process and on the properties of the
dealloyed materials, leaving the theoretical study incomplete to fully
understand the fundamental mechanisms of LMD. In this paper, we use theoretical
models and phase-field simulations to clarify the kinetics and pattern
formation during LMD. Our study starts from a theoretical analysis of the 1D
dissolution of a binary precursor alloy, which reveals that the 1D dissolution
process involves two regimes. In the first regime, due to the low solubility of
one of the elements in the melt, it accumulates at the solid-liquid interface,
which reduces the dissolution kinetics. In the second regime, the interface
kinetics reaches a stationary regime where both elements of the precursor alloy
dissolve into the melt. Previous works revealed that in the early dealloying
stage, the dealloying front is destabilized by an interfacial spinodal
decomposition, which triggers the formation of interconnected ligaments. We
extend this line of work by proposing a linear stability analysis able to
predict the initial length-scale of the ligaments formed in the initial stage
of the dealloying. Combining this analysis with the 1D dissolution model
proposed here enables us to better understand the initial conditions
(composition of the precursor alloy and the melt) leading to a planar
dissolution without interface destabilization. Finally, we report a strong
influence of solid-state diffusion on dealloying that was overlooked in
previous studies. Although the solid-state diffusivity is four to five orders
of magnitude smaller than in the liquid phase, it is found to affect both
dissolution kinetics and ligament morphologies.
