Zirconia slip casting

Slip-casting of technical ceramics has been steadily introduced over the past 60 years or so, and now it is standard practice to cast alumina crucibles and large tubes. The process has been successfully extended to include silica, beryllia, magnesia, zirconia, silicon (to make the preforms for reaction-bonded silicon nitride articles) and mixtures of silicon carbide and carbon (to make the preforms for a variety of self-bonded silicon carbide articles). Many metallics and intermetallics, including tungsten, molybdenum, chromium, WC, ZrC and MoSi2, have also been successfully slip-cast. 

Mixed ion and electronic conducting ceramic membranes (e.g. yttria-stabilized zirconia doped with titania or ceria) can be slip cast into a tubular form from the pastes containing the constituent oxides in an appropriate proportion and other ingredients and the cast tubes are then subject to sintering at 1,200 to 1,500X to render them gas impervious [Hazbun, 1988]. 

Moreno, R., Requena, J., and Moya, J.S., Slip casting yttria-stabilized tetragonal zirconia polycrystals, J. Am. Ceram. Soc., 71,1036, 1988. 

Shan, H. and Zhang, Z., Slip casting of nanometre sized tetragonal zirconia powder, Br. Ceram. Trans., 95, 35, 1996. 

R. Moreno, A. J. S nchez-Herencia, and J. S. Moya, "Functionally Gradient Materials by Sequential Slip Casting Alumina-Yttria Tetragonal Zirconia" pp. 149-56 in Ceramic Transactions, Vol. 34, Functionally Gradient Materials. Edited by J. B. Holt, M. Koizumi, T. Hirai, and Z. A. Munir. American Ceramic Society, Westerville, OH, 1993. 

Huisman, W., Graule, T., and Gauckler, L.J., Centrifugal slip casting of zirconia... 

By this method, the grain size, particle shape, agglomerate size, and specific surface area can be modified within a certain degree by controlling the precipitation and calcination conditions. Furthermore, its purity is also more easily controlled. For the applications of zirconiain the slip casting, tape casting, mold injection, particle size, specific surface, etc. are important characteristics. Well-controlled precipitated zirconia powder can be fairly uniform and fine. 

Figure 3. Effective tensile modulus of dense alumina-zirconia composite ceramics Voigt bound (crosses slightly above the upper solid line calculated from the Voigt values of the effective shear and bulk moduli), approximate Voigt bound (according to the mixture rule, upper solid line), Reuss boimd (results of both calculations identical, crosses and lower solid curve), upper and lower Hashin-Shtrikman bounds (dashed curves) and values measured by the resonant frequency method for dense (porosity < 3 %) alumina-zirconia composite ceramics prepared by slip casting.

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