Our work is based on a phase field approach to simulate the evolution of domains in ferroelectric material. In particular we are focusing on materials with orthorhombic crystal symmetry, namely NaNbO3, which exhibit 12 admissible polarization directions in three dimensions. We present a novel approach to define a phase field potential to model the microstructure with the desired symmetry. The model is formulated in three dimensions as the orthorhombic symmetry does not allow for plane formulations anymore. Precipitation hardening has emerged as a new approach to enhance the mechanical properties of ferroelectric material, as recent studies have shown. As an alternative to doping, it effectively reduces domain wall mobility as well as heat dissipation. We are furthermore investigating the material system of NaNbO3 with LiNbO3 particles, where the orthorhombic ferroelectric is combined with precipitates of hexagonal symmetry. The interaction between matrix and precipitate produces new microstructure phenomena, contributing to the development of a new generation of ferroelectric material.