Ceramics structural analysis

Due to these virtues, solid state NMR is finding increasing use in the structural analysis of polymers, ceramics and glasses, composites, catalysts, and surfaces. 

Let us concentrate a little longer on ceramics. Here micro-analysis only slowly won ground and the application of solid state physics lagged behind. Very slowly the relationship between the properties of a material and its microstructure was being discovered. Metallurgy had already been characterized by a theoretical approach for some time and consequently metals were about 15 times as important as ceramic materials in 1960 (see Ashby s graph). This was of course influenced by the fact that metals have relatively simple structures which, in their turn, simplify theoretical comtemplations. Ceramic structures are very often complex and are characterized by multiphase systems. However, at present ceramic materials are approached much differently than for instance in 1900. 

Hydroxycarboxylic acids, which include citric acid, malic acid, lactic acid, etc., are benign to the environment and very convenient for the solution processing. Moreover, since these reagents can form stable complexes with other cations, they rarely yield a precipitate. For several complexes single crystals of well-defined composition suitable for the X-ray structural analysis were isolated. Thus, these water-soluble titanium complexes of hydroxycarboxylic acids are promising precursors for the synthesis of ceramics from an aqueous solution and their industrial utilization is expected in the future. In this chapter we decribe the method of synthesis, structural analysis, and stability of these complexes. The examples of multicomponent oxide materials preparation using these compounds are presented. 

Simultaneous Crystallite Size, Strain and Structure Analysis from X ray Powder Diffraction Patterns, S. A. Howard and R. L. Snyder, NYS College of Ceramics Technical Publication, New York State College of Ceramics, Alfred University, Alfred, NY 14802, USA... 

Takeda, M. 1996. Mechanical and structural analysis of silicon carbide fiber Hi-Nicalon types. Ceramic Engineering and Science Proceedings 17(4-5) 35 2. 

Hempel, H. and Wiest, H. (1986) Structural analysis and life prediction for ceramic gas turbine components for the Mercedes-Benz Research Car 2000. ASME Paper No. 86-GT-199. 

Leonard, A.). (1977) Structural analysis of the transition phases in the kaolinite-mullite thermal sequence. J. Am. Ceram. Soc., 60 (1-2), 37-43. 

M. Nakagawa, M. Senga and Y. Seino, Structural Analysis of Solid Elec-trol5des for Lithium Secondary Battery. Structural Analysis of Lithium Sullide/Diphosphorus Pentasullide-Based Glass and Glass Ceramics by Solid P-NMR Method , Idemitsu Giho, 2008, 51, 197. 

The ceramics structure data, from analysis of the fracture images obtained by AFM in "height" and "Mag-cos" modes (figures 9 and 10) prove the X-ray data In all cases the material consists of polycrystalline blocks, which shape and size depend on the dopant. The... 

S. Rahman, N. N. Nemeth, and J. P. Gyekenyesi, Life Prediction and Reliability Analysis of Ceramic Structures Under Combined Static and Cyclic Fatigue, 1998 ASME Turbo Expo Land, Sea, and Air, Stockholm Sweden, June 2 5, 1998, Paper No. 98 GT 569. 

D.M. Smith, T.E. Holt, D.P. Gallegos, and D.L. Stermer Pore structure analysis via NMR, mercury porosimetry, and dynamic methods, in Advances in Ceramics, Vol. 21, Ceramic Powder Sdence(Messing G.L., (Joe) Mazdiyasni K.S., McCauley J.W. Haber R.A., eds) The American Ceramic Sodety, Columbus, OH (1987) 779-791... 

One of the original applications of AES, and still one of the most important, is the analysis of grain boundaries in metals and ceramics. Very small amounts of impurity or dopant elements in the bulk material can migrate under appropriate temperature conditions to the boundaries of the grain structure and accumulate there. In that way the concentration of minor elements at the grain boundaries can become... 

The inherent sensitivity of NMR signals to the fluid-substrate interactions via a large number of mechanisms provides a direct connection between the NMR measurables, the pore structure and the motional characteristics of the imbibed fluid. While the large number of potential NMR variables makes the experimental design and analysis complex, it also provides the potential for a measurement method capable of measuring and spatially resolving the parameters of interest to functionalized ceramics. 

We will confine ourselves to those applications concerned with chemical analysis, although the Raman microprobe also enables the stress and strain imposed in a sample to be examined. Externally applied stress-induced changes in intramolecular distances of the lattice structures are reflected in changes in the Raman spectrum, so that the technique may be used, for example, to study the local stresses and strains in polymer fibre and ceramic fibre composite materials. 

---