BEARINGS | CERAMICS
CERAMIC BEARINGS KEY QUESTIONS TO ASK
Just 20 years ago, scientists
discovered zircon in rocks
that showed life might have
started 500 million years
earlier than previously thought. This
incredible compound has made
a huge impact, as has its oxide,
zirconia, which is used to make full
ceramic bearings.
Are the increased costs worth it?
Full ceramic bearings are generally
rounder, smoother and harder than
steel, offering superior corrosion
and heat resistance, higher
dimensional stability and lower
density. However, this comes at a cost.
Ceramic bearings are significantly
more expensive than their steel
counterparts.
So, when does investing in
ceramic bearings become
worth it?
High value applications, like lab
equipment, have exact requirements
that need to be hit every time the
application is used. Using the wrong
components in such equipment can
contaminate study conditions or
cause the study to cease
altogether. This is the same
with medical equipment,
Chris Johnson, managing director of specialist bearing
supplier, SMB Bearings, explains the three most
overlooked factors concerning full ceramic bearings.
where the non-contaminating and
non-magnetic properties of
ceramic bearings prove vital.
Take Magnetic Resonance
Imaging (MRI) for example, the
imaging technique associated mostly
with hospital MRI scanners. This
technology uses a strong magnetic
field to generate two- or threedimensional
images of any living
subject. Standard steel bearings
cannot be used in these scanners
due to their magnetic properties, so
ceramic bearings are the best choice
to use in these high-value applications.
Similarly, as integrated circuit
manufacturers strive to make
their chips faster, smaller and less
expensive, semiconductor fabrication
equipment companies become more
dependent on advanced ceramic
components to achieve the desired
performance. Using bearings made
from silicon nitride, rather than the
standard alumina (aluminium oxide),
provides electrical insulation and
good corrosion resistance.
Silicon nitride’s resistivity and
dielectric constant are similar to that
of alumina, but the material is far
stronger due to its microstructure.
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