  Diffuse interface descriptions offer many advantages for the modeling of
microstructure evolution. However, the numerical representation of moving
diffuse interfaces on discrete numerical grids involves spurious grid friction,
which limits the overall performance of the model in many respects.
Interestingly, this intricate and detrimental effect can be overcome in Finite
Difference (FD) and Fast Fourier Transformation (FFT) based implementations by
employing the so-called Sharp Phase-Field Method (SPFM). The key idea is to
restore the discretization induced broken Translational Invariance (TI) in the
discrete phase-field equation by using analytic properties of the equilibrium
interface profile. We proof that this method can indeed eliminate spurious grid
friction in the three dimensional space. Focussing on homogeneous driving
forces, we quantitatively evaluate the impact of spurious grid friction on the
overall operational performance of different phase-field models. We show that
the SPFM provides superior degrees of interface isotropy with respect to energy
and kinetics. The latter property enables the frictionless motion of
arbitrarily oriented diffuse interfaces on a fixed 3D grid.
