We investigate the drying process of monodisperse colloidal film over a
wide range of Péclet number (Pe) by using the Brownian dynamics
simulation. We analyze the detailed process in three aspects;
accumulation front, normal stress, and microstructure. The evolution of
particle distribution is quantified by tracking the accumulation front.
The accumulated particles contribute to the continuous increase of the
normal stress at the interface. At the substrate, the normal stress
first stays constant and then increases as the accumulation front
touches the substrate. We quantitatively analyze the stress development
by a scaled normal stress difference between the two boundaries. At all
tested Pe, the stress difference increases to the maximum, followed by a
decrease during drying. Interestingly, a mismatch is observed between
the stress difference maximum and the initial stress increase at the
substrate. The microstructural analysis reveals that this mismatch is
related to the microstructural development at the substrate.
Microstructures and mechanics in the colloidal film drying process
