Zirconia Drawing Machine Tower Round , Wire Wheels , Reel

The transformation of Zirconia from tetragonal to monoclinic is large around
5%. It results in limiting its elasticity and fracture and formation of cracks
in zirconia ceramics. Zirconia is mixed with calcium oxide (CaO),
magnesia
(MgO), or yttria (Y2O3) to stabilize in tetragonal or cubic phase. Partially
Stabilized Zirconia (PSZ) consists of cubic, tetragonal, including monoclinic
phases of zirconia. Tetragonal zirconia
polycrystals
(TZP) are the purest form of the tetragonal phase compared with other phases.
PSZ and TZP are considered for fabrication of the biomedical device and
scaffolds. Tables 1.7 and 1.8 summarize the mechanical properties of zirconia
ceramics. The strength and fracture toughness of Yttria-TZP ceramics is quite
considerable and almost twice that of alumina. Therefore, zirconia heads are
less susceptible to the stress when contacting with metal cones. Nowadays most
medical-grade zirconia from PSZ tetragonal zirconia is considered for medical
device development. It shows minimal
microhardness
and elastic modulus, good strength, and fracture toughness than that of
alumina. Developing ceramic ball heads below 32 mm is possible from Zirconia as
it has superior mechanical strength.

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