Nonlinearity and Domain Switching in a 3D‐Printed Architected Ferroelectric

Recent advances in 3D printing have enabled fabrication of architected functional ceramics with tunable functionalities at reduced weight and cost. An essential cornerstone of materials design is to determine structure–property relations. For polycrystalline ferroelectrics, such relationships can be complex due to several microscopic mechanisms, such as lattice strains and/or domain switching, which show nonlinear dependence on external stimuli and are furthermore dependent on grain orientations. For architected materials, these microscopic mechanisms can also be spatially nonuniform. Herein, the development of appropriate methodology is entailed to correlate functional properties of architected ferroelectrics with spatial‐ and orientation‐resolved microscopic mechanisms. Herein, using in situ orientation‐resolved X‐ray microdiffraction, it is shown that nonlinear polarization and strain responses in a 3D‐printed architected ferroelectric are driven by localized progression of non‐180° domain switching, which depends not only on the internal distribution of electric‐field lines but also on the evolving long‐range stress fields resulting from inhomogeneous domain‐switching transformation strains. In this current study, it is indicated that nonlinear behavior in architected ferroelectrics can be effectively tuned by appropriate design of sample geometry, which controls the internal electric‐field distribution in the material.