We also produce our standard range of ceramic crucibles made from
zirconia. Because of a larger shrink rate during the sintering
process, zirconia crucibles are slightly smaller than Alumina
crucibles. The dimensions provided below are for Discounts are
available for volume orders, please contact us for further details.
We can also produce special crucibles for specific requirements
Zirconia (ZrO2) offers three advantages over alumina: it is more
refractory, having a melting point some 500oC above alumina, it is
readily machined and gives a high quality surface finish and it is
a useful oxygen anion conductor for use in sensors and fuel cells.
However it is considerably more expensive than alumina.
Zirconia has the complication of being metastable and needs to be
stabilised before it can be put to use. The addition of small
quantities of stabilising oxides such as CaO, MgO and best of all
Y2O3 allow the high temperature cubic phase to stabilise itself.
Partially stabilised zirconia can also be used as a toughening
agent in alumina. The zirconia-toughened alumina (ZTA) shows a
considerable improvement in strength and more importantly
toughness. As a result, these ceramics can be used in areas of
extreme mechanical abrasion and thermal shock.
Fully stabilised zirconia (FSZ) produces a high-density ceramic on
sintering. The grain size is relatively large at 10-40m m and the
ceramics are often translucent in appearance. Recent optimisation
of zirconia powders have resulted in a readily sinterable high