Home

ceramicshell

Ceramicshell is a term used to describe a high-temperature ceramic shell used in molding and coating processes, most commonly in investment casting. In this context, a wax or polymer pattern is formed in the shape of the desired part. The pattern is repeatedly dipped into a ceramic slurry and coated with a ceramic particulate layer, building up a thin, thermo-stable shell around the pattern. After several coatings and drying, the shell is a rigid mold. The pattern is burnt out in a furnace, leaving a hollow ceramic shell that can withstand molten metal at casting temperatures. The shell is then filled with molten metal, which cools to form the final part. Once solidified, the ceramic mold is fractured and removed.

Ceramic shells are typically made from refractory silica- or alumina-based materials, sometimes incorporating zirconia or other

See also: investment casting, ceramic mold, ceramic coatings.

additives
to
improve
strength
and
thermal
shock
resistance.
Shell
thickness
is
tuned
for
specific
metals
and
part
geometry,
often
on
the
order
of
1
to
3
millimeters.
The
process
allows
complex
geometries
and
fine
surface
finishes,
enabling
near-net-shape
components
used
in
aerospace,
automotive,
and
power
generation
sectors.
Limitations
include
the
brittleness
of
ceramic
molds,
long
production
cycles,
and
cost,
especially
for
low-volume
runs.
Variants
of
the
process
include
different
slurry
chemistries
and
firing
regimes
to
control
strength,
permeability,
and
surface
quality.