Many properties such as mechanical strength, thermal conductivity, electrical resistivity, and the performance of materials are determined by defects. To understand defects, it is necessary to understand ideal structures.
This book lays the foundation for structures and defects at the most basic level, with treatments similar to those found in introductory materials science and engineering textbooks. These include electron configurations, chemical bond types, and basic structures of metallic, covalent, and ionic materials. The book builds from this foundation by covering topics in greater depth and employing more sophisticated tools for its explanations, such as vector calculus, chemical and phase thermodynamics, and statistical mechanics.
The book is divided into six chapters, starting with a chapter on the properties of electron orbitals and their relation to the periodic table. The rules applied to the order in which electron orbitals are filled are described.
Chapter 2 recounts various types of chemical bonds that form in solids—the familiar ionic, covalent, and metallic bonds. The nature of bonding forces between point charges (Coulombic), permanent dipoles, induced dipoles, and the sharing of electrons between atoms are described. The dependence between electronic energy levels and the elastic modulus, melting temperature, and thermal properties are shown.
Chapter 3 describes a wide variety of crystal structures that solids form, as well as the rules and geometric constraints governing the structures. The structures of metal oxide compounds are covered in-depth. Specific structures of metal oxide compounds of technological relevance such as zinc oxide, titanium oxide, spinel, and perovskites are discussed.
Point defects, including the solubility of impurities and the equilibrium between cation and anion vacancies, interstitials, and mobile charges, are thoroughly covered in chapter 4. The equations controlling defect reactions such as the requirements of mass balances and electroneutrality are described and illustrated with several specific examples. Fang points out that incorporating even small concentrations of impurities into crystals inevitably reduces the material’s Gibbs free energy, which is why it becomes difficult to attain high purities.
Chapter 5 describes the structure of dislocations, the stress fields they create, their strain energies, and how they interact with externally applied forces and each other.
Chapter 6 covers two-dimensional defects, including grain boundaries, phase boundaries, and surfaces. Three-dimensional defects, including inclusions and pores, typically due to the formation of a second phase, are also covered. The tendency of a secondary phase to form at grain-boundary junctions is explained in terms of surface and interfacial energies.
Stylistically, the book is highly organized and logically sequenced. The author favors short passages and lists of key concepts. Then, the eight essential features of edge dislocations—the definition, the relative positions of its Burgers and sense vectors, and its response to stress—are given in a list in its subsection. The most significant concepts are depicted in plain schematic line drawings; there are very few images of actual materials.
This is a good advanced treatment of the relationships between structures and defects. The bibliography lists 76 books and journal articles ranging from 1953 to 2015, and includes many classic materials science and engineering textbooks on thermodynamics, ceramics, and crystal structures. Although it does not contain any problems, it is nevertheless a good textbook, as it has the breadth and depth necessary to provide an excellent foundation on these essential materials science and engineering topics.
Reviewer: J.H. Edgar, Department of Chemical Engineering, Kansas State University, USA.
