Material Structure and Properties

In this branch of ceramics substances are used with many different properties. Of all these properties, high melting points and high hardnesses stand out. Table 11.7.1 lists nine sub-stances with high melting points, among which some ceramic materials. 

According to literature sources mainly oxides, nitrides, borides and carbides are used as ceramic raw materials of chemical and structural applications and the most common elements in these compounds are Be, Mg, Ca, Ti, V, Cr, Y, Zr, La, Hf, W, B, Al, Si and Sn. These elements can be found in rather small area of the periodic table, i.e. in the groups 2 up to and including 6, 13 and 14. So apparently relatively few ingredients are used in this branch of ceramics to produce a wide range of products. The tricks of the trade are in the preparation. The properties are determined by a number of factors, such as the nature of the building blocks, the kind of bonds, the strength of the bonds, the crystal structure and the reactivity of the material. 

In the chapter Chemisty we have seen that every bond is partly ionic and partly covalent. As a general rule materials which are mainly 

TiC 20% ionic directed covalent bonds melting point 3100 °C 

Let us now have a closer look at the four most used materials and some of their applications. 

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Advances in computational capability have raised our ability to model and simulate materials structure and properties to the level at which computer experiments can sometimes offer significant guidance to experimentation, or at least provide significant insights into experimental design and interpretation. For self-assembled macromolecular structures, these simulations can be approached from the atomic-molecular scale through the use of molecular dynamics or finite element analysis. Chapter 6 discusses opportunities in computational chemical science and computational materials science. 

Bertrand P, Jonas A, Laschewsky A, Legras R (2000) Ultrathin polymer coatings by complex-ation of polyelectrolytes at interfaces suitable materials, structure and properties. Macromol Rapid Commun 21 319-348... 

Fullerene-Based Materials Structures and Properties Volume Editor Prassides, K. 

R. A. McCurrie, Ferromagnetic Materials—Structure and Properties , Academic Press, London 1994. 

Following these two surveys, we conducted a literature review based upon Ceramic Abstracts for the years 1988-2002. The results are summarized in Table 2.1. The results presented in Table 2.1 indicate that there has been a significant increase in the literature on CBPCs in recent years. The major thrust of the research has been in biomaterials and dental cements. Though small in number, there have been several articles in structural materials applications, which also include oil well cements. Interest in conventional refractory materials has continued, and as expected, all the applications have been supported by research in materials structure and properties of the CBPCs. 

The early world of materials discovery consisted solely of empirical observations, without an understanding of the relationship between material structure and properties. Each civilization had specific needs e.g., materials for shelter, clothing, warfare), and adapted whatever materials were available at the time to address these desires. Although this suitably addressed whatever issues were of societal concern at the time, such a trial-and-error manner of materials design resulted in slow growth. 

K. Prassides, ed. (2004) Structure Bonding, vol. 109 - An entire volume of this journal with the theme Fullerene-based materials structures and properties . 

The modem methods of experimental and theoretical analysis of polymer materials structure and properties allow not only to confirm earlier propounded hypotheses, but to obtain principally new results. Let us consider some important problems of particulate-filled polymer nanocomposites, the solution of which allows to advance substantially in these materials properties understanding and prediction. Polymer nanocomposites multicomponentness (multiphaseness) requires their stmctural components quantitative characteristics determination. In this aspect interfacial regions play a particular role, since it has been shown earlier, that they are the same reinforcing element in elastomeric nanocomposites as nanofiller actually [1]. Therefore, the knowledge of interfacial layer dimensional characteristics is necessary for quantitative determination of one of the most important parameters of pol5mier composites in general their reinforcement degree [2, 3]. 

The underlying themes of this Chapter have been the value of ROMP in well-controlled polymer synthesis and the relationship between the structure and organisation of the electroactive polymers in the solid state and their physical properties. In the case of both polyacetylene and polar polymers, developments in initiator specification have resulted in increased precision and control in polymer synthesis with concomitant improvement in the definition of product material structures and properties. 

Reinforced matrix and composite material Beyond these kinds of fiber-reinforced biomaterials that aim to be cell-cultured, cell-infiltrated and then given compliant neo-tissue, fiber-reinforced biomaterials could have a much more structural function comparable to common composite materials used in automotive and aeronautic industry, for example. Fibers embedded in a polymer matrix could then, depending on materials structure and properties, provide a strong enough substitute to replace conventional biomaterials like stainless steel and titanium. Only fiber-reinforced composite materials allow to reach such high mechanical strength. 

P. Bertrand, A. Jonas, A. Laschewsky and R. Legras, Ultrathin polymer coatings by complexation of polyelectrolytes at interfaces Suitable materials, structure and properties. Feature Article., Macromol. Rapid Commun., 21,319-348 (2000). 

Legras R (2000) Ultrathin polymer coatings by complexation of polyelectrolytes at interfaces suitable materials, structure and properties. 

The observation of images of composites may lead to qualitative conclusions only, but it does mean that the existence of certain objects and their reciprocal relations may be confirmed. The quantitative data and their analysis is necessary for rational design of composite materials and for effective determination of the relation between the materials structures and properties. Computer image analysis has been developed over the last 20 years to enable quantitative analysis on the basis of images of any kind. Using a basically similar approach to an image as in manual or semi-automatic methods, the fully automatic approach offers much greater possibilities of quantitative determination of various parameters that characterize the structures of the materials. 

Leszczyhski W. Starch— industrial raw material, structure and properties. Zesz Probl Post p Nauk Rol 2004 500 69-98. (in pohsh). 

The different adhesion forces are highly dependent on the material properties which are a function of the material structure. Thus differences in material structure and properties are explained before the three mentioned adhesion principles are discussed. 

The literatme on indentation testing of UHMWPE has covered a variety of aspects of the behavior of UHMWPE. These include effects of processing, oxidation, prior deformation, extent of crystallinity, frequency of loading, and several other issues related to UHMWPE. Indentation tests have spanned a range of sizes from nanoindentation up to indentation tests in the scale of tens of microns. The advantages of these nano- and microscale tests include the ability to sample very small regions of the material, an ability to profile mechanical properties in a single sample at small intervals (hundreds of nanometers and tens of microns, respectively), and an ability to correlate the indentation response with other measurements of material structure and properties. 

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