Beyond Elastocapillarity: Plastic Deformation by Surface Tension

We study how capillary forces can plastically deform yield stress materials on small scales. We present an elastoviscoplastic continuum model to simulate flows with deformable interfaces, from elastocapillarity to plastocapillarity (arXiv:2306.06640). We will first focus on the deformation of droplets under fully wetting conditions and show how different non-dimensional groups, including Plastocapillarity and Deborah numbers, govern the dynamics and final shape of the droplets. Next, we present a class of problems in which plastic deformation by surface tension becomes important. Finally, we discuss a number of open problems. Our work finds applications in 3D printing and small-scale coating of complex fluids