Surface Properties of Ceramics

Szymezyk, A. et al.. Characterisation of surface properties of ceramic ultrafiltration membranes by studying diffusion-driven transport and streaming potential. Desalination, 119, 303, 1998. 

Various techniques have been developed to characterize the surface properties of ceramic powders [43 5]. Generally, the principles of surface characterization techniques are to use the interactions of the samples with atomic particles, such as atoms, ions, neutrons, and electrons, or radiations, such as X-rays and ultraviolet rays. Various emissions are produced during the interactions, which are collected as signals to analyze the samples. Figure 4.8 shows the principal emissions caused by the interactions of an electron beam with solid particles. 

A. Surface Properties of Nanophase Ceramics for Enhanced Orthopedic and Dental Implant Efficacy... 

Due to their ability to selectively promote both osteoblast and osteoclast function, nanophase ceramics provide a preferable alternative to conventional orthopedic and dental implants that fail to integrate with surrounding bone it is undoubtedly highly desirable to minimize, if not avoid, clinical complications that necessitate removal of failed implants as a result of poor surface properties that lead to insufficient osseointegration. These results provide evidence that nanoceramics may be synthesized to match surface properties of bone and, thus, demonstrate strong promise and potential for their use in orthopedic and dental applications. 

Macroscopic properties of ceramic materials are often dominated by localized imperfections such as defects, impurities, surfaces and interfaces. Systematically-doped polycrystalline materials exhibit wider variety of properties as compared with monolithic single crystals. Some of them serve key roles in high-tech society and they are referred to as fine ceramics or advanced ceramics. An ultimate objective of the ceramic science and technology is to understand the nature and functions of the localized imperfections in order to achieve desired performances of materials intellectually without too much accumulation of empirical knowledge. 

The optical properties of ceramics are useful in the ultraviolet, visible, and infrared ranges of the electromagnetic spectrum, and one key quantity used to describe the optical property of a material is the refractive index, which is a function of the frequency of the electromagnetic radiation. Other quantities used to characterize optical performance are absorption, transmission, and reflection these three properties sum to unity and are also frequency dependent. The last three properties govern many aspects of how light interacts with materials in windows, lenses, mirrors, and filters. In many consumer, decorative, and ornamental applications, the esthetic qualities of the ceramic, such as color, surface texture, gloss, opacity, and translucency, depend critically on how light interacts with the material. 

Bergstrom, L. et al.. The effect of wet and dry milling on the surface properties of silicon nitride powders, in Ceramics Today—Tomorrow s Ceramics, Vincenzini, P., ed., Elsevier, New York, 1991, p. 1005. 

As the properties of ceramics monoliths are examined, it s important to note that changes or improvements in melting temperature, thermal shock resistance, strength, back pressure and/or catalyst surface area each have an effect on other properties. The present ceramic monolith design is the result of a compromise of these interrelated variables. 

The major physical properties of ceramic powders constitute size distribution of primary particles and agglomerates, specific surface area, density, porosity, and morphology (e.g., shape, texture, and angularity). 

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