Ceramic powder processing concepts

Each chapter is broken into sections wdth the first section always stating the objectives of the chapter, and the last section always providing a summary of the chapter. In the text, problems are worked to elucidate the points discussed. Finally at the end of each chapter there are tmworked problems that the students can do for homework. The book attempts to provide a large list of references for specific concepts and ideas presented elsewhere, and we hope that the reader will refer to these references for the derivation of specific equations not presented. This book is hi ily mathematical in comparison with other texts in the field, because this field should be mudi more quantitative than heretofore presented. With these mathematics, the field of ceramic powder processing can become more quantitative in the future. 

Thus this book presents current developments and concepts in the chemical techniques for production and characterization of state-of-the-art ceramic materials in a truly interdisciplinary fashion. The 27 chapters are divided into five parts reflecting topical groups. The first part discusses the starting materials—how to prepare and modify them in the nanoscale range. Powders are the most heavily used form of starting ceramic materials. The synthesis, characterization, and behavior of ceramic powders are presented in parts I and II. In the third part, processing of ceramic films via the sol-gel technique is discussed. Fabrication of... 

Interfacial phenomena at metal oxide/water interfaces are fundamental to various phenomena in ceramic suspensions, such as dispersion, coagulation, coating, and viscous flow. The behavior of suspensions depends in large part on the electrical forces acting between particles, which in turn are affected directly by surface electrochemical reactions. Therefore, this chapter first reviews fundamental concepts and knowledge pertaining to electrochemical processes at metal oxide powder (ceramic powder)/aqueous solution interfaces. Colloidal stability and powder dispersion and packing are then discussed in terms of surface electrochemical properties and the particle-particle interaction in a ceramic suspension. Finally, several recent examples of colloid interfacial methods applied to the fabrication of advanced ceramic composites are introduced. 

LNA, which is an acid, can adsorb on alumina via acid-base interaction or hydrogen bonding. The structural formula of LNA and those of other organic dispersants are given in Fig. 2. The interaction between the solvent and LNA cannot be responsible for the viscosity curves because the most basic solvent, tetrahydrofuran (THF) [11], would interact with LNA the most. The acid-base interaction is based on Drago s work on Lewis acid-base interaction energies [12]. Fowkes [2,13,14] expanded the concept to ceramic processing. The relative acidity and basicity of solvents used are listed in Table 1. The ceramic powders used are listed in Table 2. 

Sintering is defined as a process in which distinct particles in a powder weld together and interdiffuse with each other at temperatures below their melting point. The concept has been employed in the fields of powder metallurgy and ceramics for hundreds of years. Sintering allows metal particles, whether nanoparticles for inkjet applications or larger particles for other printed electronics applications, to join together at a temperature below the melt phase in order to form the conductive path. 

The concept of pressure due to surface curvature is very important in ceramics because we often encounter very curved surfaces, e.g., at small grains, voids, or particles, which are present because we start processing with powders. Thus we can have a large pressure difference that... 

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