  A novel phase field model has been developed to study the effect of coherent
precipitate on the Zener pinning of matrix grain boundaries. The model accounts
for misfit strain between precipitate and matrix as well as the elastic
inhomogeneity and anisotropy between them. The results show that increase in
elastic misfit, elastic inhomogeneity, and elastic anisotropy increases the
coarsening rate of the precipitates. Increased coarsening of precipitates in
turn decreases the pinning of grain boundaries. Therefore, increase in misfit
strain, elastic inhomogeneity and anisotropy negatively affect the Zener
pinning through coherent precipitate. This study shows elastic anisotropy gives
rise to the needle shape precipitate. It has also been shown that these needle
shaped precipitates are not very effective in Zener pinning. This study
provides an understanding into the effect of coherent precipitate on the Zener
pinning of matrix grain boundaries.
