ABSTRACT
For all the diversity of SHS systems, presented in the first chapter, there are common fundamental principles of materials synthesis in the combustion mode. Consideration of these principles is the focus of this chapter. The literature on combustion synthesis of materials regularly uses terms such as stationary, equilibrium, reversibility, and stability, which are applied to both the reaction systems and the process, and sometimes to the products of synthesis. It is often assumed that these concepts are well known and their definitions are not necessary. Also many thermodynamic functions and values, such as internal energy, enthalpy, thermodynamic potentials, chemical potentials, the heat of reaction, and so on are widely used without explanations of their meanings. No wonder one gets lost in all these complexities, because even in different books on thermodynamics one can find different definitions of basic concepts and thermodynamic quantities. An even more difficult case is the kinetics of heterogeneous combustion: what is the rate of reaction in a multiphase system or what is the effective activation energy of the heterogeneous process. These and many other questions require separate discussion and analysis before the corresponding concepts can be correctly used.
