Influence of Structure on Materials Properties

As mentioned above, properties of a material are influenced by that material s structure, which in turn is influenced by the material s processing. To complete the circular discussion, processing methods used for a material are often dictated by the material properties. Processing or fabrication methods and their influence on materials constitute the bulk of this chapter. A brief discussion of the influence of structure on properties will help put these effects into perspective. 

When discussing the properties of many materials, the term crystallographic orientation, or texture (introduced in Section 1.2.3), is often used. Crystallographic 

A component or object in which grain orientations are completely random is said to have no texture. If the material exhibits some preferred orientation, it is said to have a texture. The texture can be weak, moderate, or strong, depending on the percentage of grains that have the preferred orientation. Texture is produced in most materials, either as an unintended by-product of the processing method or with the intention to exploit favorable properties in one orientation. In some cases, processing methods or routes are chosen explicitly to develop a preferred texture. 

A pole figure references a particular Bragg reflection that is, a (100) pole figure in a textured sample would differ from a (111) pole figure (whereas for a 

Texture is nearly impossible to avoid in most material processing techniques. In some cases it may be advantageous to develop a particular texture, whereas 

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Because the stmctures of TPEs are diverse, the influence of structure on mechanical properties may not be universal for all materials. Nevertheless,... 

When he interviewed with Meyer in 1926, Mark outlined a typically thorough program. He proposed a team of organic and physical chemists, and physicists who would evaluate the influence of structure on properties such as rigidity, elasticity, melting point, and water absorption. Work, he proposed, would shift toward new material development and into the manufacturing facilities to evaluate the effects of processing... 

In the last chapter, the formal description of linear elasticity was introduced. It was shown that knowledge of the elastic constants for a particular material allows one to describe the strains produced by any arbitrary state of stress. In materials science one is often interested in controlling a material property and, thus, this chapter is concerned with the influence of structure on the elastic constants. At the most basic level, the elastic constants reflect the ease of deformation of the atomic bonds but it will be shown that other levels of structure can be very important, especially with the use of composite materials. 

The objectives of this work were to study the production of carbon molecular sieves from a Greek lignite with a high mineral matter content, to investigate the influence of the starting material properties (inorganic matter and pore structure) on the produced CMS surface area and separation capacity for CO2/CH4 and N2/O2 gases, and to determine the optimum experimental conditions for the production of molecular sieves with desired properties. 

The present investigation deals with the stress state of the SijN. -TiN-MgO system and with the influence of structure on physico-mechanical properties of the material. 

After a temptative structure-based classification of different kinds of polymorphism, a description of possible crystallization and interconversion conditions is presented. The influence on the polymorphic behavior of comonomeric units and of a second polymeric component in miscible blends is described for some polymer systems. It is also shown that other characterization techniques, besides diffraction techniques, can be useful in the study of polymorphism in polymers. Finally, some effects of polymorphism on the properties of polymeric materials are discussed. 

The paper first considers the factors affecting intramolecular reaction, the importance of intramolecular reaction in non-linear random polymerisations, and the effects of intramolecular reaction on the gel point. The correlation of gel points through approximate theories of gelation is discussed, and reference is made to the determination of effective functionalities from gel-point data. Results are then presented showing that a close correlation exists between the amount of pre-gel intramolecular reaction that has occurred and the shear modulus of the network formed at complete reaction. Similarly, the Tg of a network is shown to be related to amount of pre-gel intramolecular reaction. In addition, materials formed from bulk reaction systems are compared to illustrate the inherent influences of molar masses, functionalities and chain structures of reactants on network properties. Finally, the non-Gaussian behaviour of networks in compression is discussed. 

Unsaturated groups are very interesting for application development because this specific functionality opens up a broad range of possibilities for further (chemical) modification of the polymer structure, and therefore its physical and material properties. The direct microbial incorporation of other functional substituents to the polymer side chains, e.g. epoxy-, hydroxy-, aromatic-, and halogen functional groups, influences the physical and material properties of poly(HAMCL) even further [28,33,35,39-41]. This features many possibilities to produce tailor-made polymers, depending on the essential material properties that are needed for the development of a specific application. 

Furthermore, we believe that the stabilizing influence of boron in the structure of graphite is connected with enhancement of its acceptor properties, which manifest themselves when Boron atoms substitute carbon atoms in the crystalline structure (hexagon ring) of carbon. Such effects are mentioned in the literature for some types of carbon materials [3] and the influence of boron on TEG can be the similar. 

The interaction of microwaves with solid materials has proven attractive for the preparation and activation of heterogeneous catalysts. It has been suggested that micro-wave irradiation modifies the catalytic properties of solid catalysts, resulting in increasing rates of chemical reactions. It is evident that microwave irradiation creates catalysts with different structures, activity, and/or selectivity. Current studies document a growing interest in the preparation of microwave-assisted catalysts and in the favorable influence of microwaves on catalytic reactions. 

Shapovalova O.M., Babenko E.P., Babenko J.V. Influence of hydrogen on structure and property of titanic powders // VII International Conference "Hydrogen materials science and chemistry of metal hydrides". - Ukraine. -2001. 

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