Material Zirconium oxide - Zirconia
Zirconia is used as high temperature refractory material, and for cutting blades. The melting-point is very high (about 2700C).
To maintain its properties zirconium oxide needs to be stabilised by addition of calcium, magnesium, or yttrium oxides.

The addition of MgO yields partially stabilised zirconia (PSZ), a relatively coarse microstructure (50-100 micron), used as refractory material (e.g. thermal barriers for high efficiency heat engines), as it retains its properties up to 1100C.

Additions of yttria (Y2O3) yield tetragonal zirconia polycrystal (TZP), a fine grained microstructure (less than 1 micron) with high strength, toughness, and flexibility (up to 500C), used as structural material or for durable cutting blades.
Danish Name Zirkonoxid
Products Ceramic advanced wet shave razor
Ceramic knife
Ceramic scissors
Honeycomb thermal insulator
Processes Powder technology
References Atlantic Equipment Engineers
Johnson Matthey GmbH
Price Zirconia is a relatively expensive material.
Zirconia powder, stabilised with calcia (CaO), purity 99.9%, costs from 200 to 500 DKK/kg depending on the amount purchased.
PSZ and TZP are more expensive and prices are available inquiring suppliers.
Additional Info The first value refers to PSZ, the second to TZP.
Colour: white to tan - yellow to brown;
Density [kg/l]: 5.75 - 6.04;
Max use temperature [C]: 1100 - 500;
E-modulus [GPa]: 200 - 206;
Thermal conductivity [W/mK]: 1.8 - 2.7.
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Copyright © 1996, 97, 98 Torben Lenau