Fine-grained ceramics

In 1986, Wakai et al. (1986) in Japan discovered that ultra-fine-grained ceramics can also be superplastically deformed they may be brittle with respect to dislocation... 

Ideally the product is a fine-grained ceramic containing interlocking crystals with sizes ranging from less than 10 nm in transparent glass-ceramics to several micrometres, with a residual, usually small, glass content. The behaviour of the material is largely determined by the choice of the cry-... 

Wang, J.G., Raj, R., Mechanism of superplastic flow in a fine-grained ceramic containing some liquid phase, J. Am. Ceram. Soc., 1984, 67(6) 399. 

Chokshi., A.H., Superplasticity in fine-grained ceramic and ceramic composites current understanding and future prospects , Mater. Scl. Eng., 1993, A166, 119-33. 

J.-G. Wang and R. Raj, Mechanism of Superplastic Flow in a Fine-Grained Ceramic Containing Some Liquid Phase, J. Am. Ceram. Soc., 67, 381-444 (1984). 

The substances involved are generally stable oxides with high melting points which make them suitable as technical refractory materials. In contrast to heavy refractories for industrial furnaces, these materials are fine-grained ceramics which, besides their ability to resist high temperature wiihout damage, also exhibit special mechanical, electrical and other properties. 

There will be a counter- A dimensionless constant and for fine-grained ceram-... 

Creep rate varies as fine-grained ceramics. 

The ability to cast thin layers (x3 pm) requires highly disperse, uniform, fine-grained ceramic powders (100-300 nm particle diameter). To achieve these particles sizes extensive milling may be used or the... 

The availability of nanopowders has led to the development of submicrometer, fine-grained ceramics, which exhibit improved mechanical properties. Many... 

Figure 6,9 Ferroelectric hysteresis loops, schematic (a) typical loop indicating P P and Ej (b) single crystal ABO (c) medium-grained ceramic ABO (d) fine-grained ceramic ABO,...

Figure 6.12 Strain versus applied electric field loops (a) symmetrical butterfly loop for a ferroelectric with a symmetrical P-E hysteresis loop (b) experimentally determined loop for a fine-grained ceramic 0.95Bi Nag iO -0.05KNbO ...

Finally we can note that the ferroelectric state of relaxors is characterised by an extremely narrow hysteresis loop with a low value for the remanent polarisation (Figure 6.19a). This sort of hysteresis loop can be considered to fall into the continuum described previously (Figure 6.9) and suggests that the microsttucture of the phases is at an even more reduced scale than the fine-grained ceramic samples. Indeed, the behaviour when the materials are either cooled in or without an external electric field (FC or ZFC) is also taken as indicative of a complex microstructure. The strain versus applied electric field loop has a U shape, rather like the central portion of the strain curve for an antiferroelectric (Figure 6.19b). 

Kaminskii AA, Rhee H, Eichler HJ, Ueda K, Takaichi K, Shirakawa A et al (2008) New nonlinear-laser effects in crystalline fine-grained ceramics based on cubic SC2O3 and LU2O3 oxides second and third harmonic generation, and cascaded self-sum-frequency mixing in UV spectral region. Laser Phys Lett 5 109-113... 

Fig. 2.62 Tensile ductility for fine-grained ceramics as a function of cxp( ) normalized by the material parameter [28]. With kind permission of Elsevier...

The term Advanced Ceramics is opposite in meaning to Traditional or Classical Ceramics. In the past. Advanced Ceramics were often confused with New or Newer Ceramics, Modern Ceramics, Special Ceramics and so on. Furthermore, Fine Ceramics, at least in the USA and Europe, is synonymous with Fine Grain Ceramic Products and/or Fine Grain Porcelain Fine Ceramics in Japan is similar to what we understand as Advanced Ceramics. So for this edition, the term Advanced Ceramics was chosen as the most suitable title for a book providing an in-depth survey of the current state of Ceramics Science and its applications. 

CorningWare CorningWare cookware is introduced. It is based on S. Donald Stookey s 1953 discovery that a heat-treatment process can transform glass into fine-grained ceramics. 

The slip-coating-sintering process is the most widely used. In this process, a porous ceramic support tube is made by pouring a dispersion of a fine-grain ceramic material and a binder into a mold and sintering at high temperature. The pores between the particles that make up this support tube are large. One surface of the tube is then coated with a suspension of finer particles in a solution of a cellulosic polymer or PVA which acts as a binder and viscosity enhancer to hold... 

Contrary to metals, ceramics do not yield plastically when loaded. Therefore, cracks cannot grow under cyclic loading by localised plastic deformation at the crack tip. Furthermore, no intrusions and extrusions can form on the surface of an initially smooth specimen by dislocation movement. Because of this, many ceramics do not exhibit any cyclic effects i. e., there is no difference between their behaviour under static and cyclic loads. All loads that they can bear once, they can bear infinitely many times. For example, this is the case in fine-grained ceramics with a single phase i.e., many technical ceramics. 

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