  Dust grains form in the clumpy ejecta of core-collapse supernovae where they
are subject to the reverse shock, which is able to disrupt the clumps and
destroy the grains. Important dust destruction processes include thermal and
kinetic sputtering as well as fragmentation and grain vaporization. In the
present study, we focus on the effect of magnetic fields on the destruction
processes. We have performed magneto-hydrodynamical simulations using AstroBEAR
to model a shock wave interacting with an ejecta clump. The dust transport and
destruction fractions are computed using our post-processing code Paperboats in
which the acceleration of grains due to the magnetic field and a procedure that
allows partial grain vaporization have been newly implemented. For the
oxygen-rich supernova remnant Cassiopeia A we found a significantly lower dust
survival rate when magnetic fields are aligned perpendicular to the shock
direction compared to the non-magnetic case. For a parallel field alignment,
the destruction is also enhanced but at a lower level. The survival fractions
depend sensitively on the gas density contrast between the clump and the
ambient medium and on the grain sizes. For a low-density contrast of $100$,
e.g., $5\,$nm silicate grains are completely destroyed while the survival
fraction of $1\,\mu$m grains is $86\,$per cent. For a high-density contrast of
$1000$, $95\,$per cent of the $5\,$nm grains survive while the survival
fraction of $1\,\mu$m grains is $26\,$per cent. Alternative clump sizes or dust
materials (carbon) have non-negligible effects on the survival rate but have a
lower impact compared to density contrast, magnetic field strength, and grain
size.
