Zirconia-toughened ceramics

N. Claussen and G. Petzow, Whisker-Reinforced Zirconia-Toughened Ceramics , in Tailoring Multiphase and Composite Ceramics, eds. R. E. 

Zirconia Toughened Ceramics. Zirconia particles can be embedded in host matrices to form a variety7 of transformation-toughened... 

Zirconia-toughened ceramics (ZTCs). These consist of tetragonal or monoclinic zirconia particles finely dispersed in other ceramic matrices such as alumina, mullite, and spinel. 

N. Claussen and G. Petzow, Whisker-Reinforced Zirconia-Toughened Ceramics pp. 649-62 in Tailoring Multiphase and Composite Ceramics, Vol 20. Edited by R. E. Tiessler, G. L. Messing, C. G. Pantano, and R. E. Newnham. Plenum Press, New Yoik, 1986. 

SWA 85] SWAIN M.V., Inelastic deformation of pg-psz and its significance for strength-toughness relationship of zirconia-toughened ceramics , Acta MetalL, 33, 11,... 

Becher, P.F. and Tiegs, T.N. (1987). Toughening behavior involving multiple mechanisms whisker reinforcement and zirconia toughening. J. Am. Ceram. Soc. 70, 651-654. 

P. F. Becher and T. N. Tiegs, Toughening Behavior Involving Multiple Mechanisms Whisker Reinforcement and Zirconia Toughening, J. Am. Ceram., 70[9], 651-654 (1987). 

Pratapa, S. and Low, I.M. (1996). The Effects of Spodumene Addition on Properties of Functionally-graded Aluminium Titanate/Zirconia-toughened Alumina Composites . In Proceedings of the 2nd International Meeting of Pacific Rim Ceramic Societies. 

It has been known for some time that considerable improvement of the mechanical properties of alumina in terms of flexural strength, fracture toughness, yield strength and elastic modulus can be achieved by adding particles of stabilised zir-conia as a structural reinforcement (see Chapter 4.1.2). Such ceramics are known as ZTA (zirconia-toughened alumina), duplex ceramics or dispersion ceramics. 

Figure 4.2 Reinforcement mechanism of a ZTA (zirconia-toughened alumina) duplex ceramics with agglomerated Y-PSZ particles.

At this stage, three classes of toughened zirconia-containing ceramics have been identified ... 

The surface of transformation-toughened ceramics can be transformed by grinding. For a single-phase, yttria-stabilized zirconia,... 

FIGURE 24.27 Two-phase ceramics, (a) As sintered and (b) heat treated at 1600°C for 30 hours. ZTA 30% (zirconia-toughened aiumina with 30 voi% YSZ containing 10 moiar% yttria). 

The ceramic materials investigated in this paper are hot-pressed silicon nitride (HPSN), reaction-bonded silicon nitride (RBSN), zirconia-toughened alumina (AI2O3), and porous SiC. The available material properties for these ceramics are given in Table 4.3. The HPSN and zirconia-toughened alumina ceramics were in the shape of flexural strength test bars cut from billets. The RBSN ceramic was molded into bars of the shape of flexural test specimens. The porous SiC ceramic was provided in the shape of flexural test specimens. 

For determining the depth of damage caused by the grinding of RBSN and zirconia-toughened alumina, the ceramic materials were first ground under a range of grit depth of cut conditions and then lapped to establish the depth... 

Grinding Test Conditions for Zirconia Toughened Alumina Ceramic... 

Flexural strength versus depth of material removed by lapping results for zirconia-toughened alumina ceramic are shown in Figure 4.11a through... 

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