This chapter provides an overview of the thermodynamics of extrusion. It begins by presenting a thermodynamic model of the extrusion process expressed in the form of finite difference equations. It then explains how the model accounts for multiple sources of heat generation, the influence of principal variables on temperature rise, and different types of temperature measurements. It also discusses the benefits of isothermal extrusion and how it achieves consistent mechanical properties in extruded components.

This chapter covers the analytical methods developed to characterize ordering phenomena in crystal structures. The chapter gives examples of ordering phenomena and discusses models for long-range ordering, such as the Bragg-Williams-Gorsky (B-W-G) model, and for short-range ordering. Examples of ordering and phase separation due to ordering by the B-W-G model are described. The chapter includes an appendix covering the effect of phase separation inversion type.

This chapter reviews the fundamentals of classical nucleation theory, with application examples. The discussion covers the basic subjects of nucleation, spontaneous nucleation in solution, nucleation by inoculation, and nucleation in solids.

This chapter provides a classification of the types of microstructural changes and transformations and then reviews each type. It presents the Johnson-Mehl-Avrami-Kolmogorov (JMAK) equation and explains the thermodynamics of eutectic solidification and eutectoid transformation. An appendix covers growth of eutectoid structure in carburized pearlite.

This chapter explains the idea of solution theory and the nature of mixed materials. The chapter considers approximation of free energy by the regular solution model and sublattice model. It discusses chemical potential and nonrandom distribution based on the interactions between solute atoms.

This chapter explains the significance of the phase diagram and its use in the development of new materials. The chapter describes the basic rules of heterogeneous equilibrium, presents a comparison between liquidus line and solidus line, and provides information on the solubility curve and the binodal curve.

This chapter considers various behaviors of microstructural interfaces from a thermodynamics viewpoint. It discusses energy of surface and interface, the Gibbs-Thomson Effect, grain-boundary segregation, smooth and rough interfaces, and grain growth.

This chapter provides a detailed discussion on the Brownian motion, diffusion coefficient , and Fick's diffusion laws. It presents a review of solid phase diffusion and discusses the mechanism of diffusion and diffusion coefficient.

This chapter provides a thorough introduction to the electrochemical thermodynamics that govern electrode reactions associated with corrosion. It begins with a review of the thermodynamic criteria for the stability of chemical reactions based on Gibbs free energy and explains how energies of formation are determined using the oxidation of iron as an example. It then considers how iron reacts with hydrochloric acid, explaining how it can be expressed as two half reactions modeled as electrodes in an electrochemical cell. It goes on to describe the chemical reactions occurring at each electrode, accounting for different variables, mechanisms, and electrochemical effects. The chapter concludes with an in-depth review of Pourbaix diagrams, explaining what they reveal about the stability of metal-water systems and the formation of corrosion products.

This chapter explains how the principles of chemical thermodynamics are used in the construction and interpretation of phase diagrams. After a brief review of the laws of thermodynamics, it describes the concept of Gibbs free energy and its application to transformations that occur in single-component and binary solid solutions. It then examines the relationship between the free energy of a solution and the chemical potentials of the individual components. It also explains how to account for the heat of mixing using quasi-chemical models, discusses the effect of interatomic bond energies and chemical potentials, and shows how the equilibrium state of an alloy can be obtained from free-energy curves.

This chapter provides a fundamental understanding of beryllium reduction thermodynamics as a prerequisite for subsequent chapters on extraction, chemical processing, and corrosion. It examines a number of reduction methods along with a potential refining process, highlighting the challenges encountered with each.

This chapter describes the basics of energy and entropy and “free energy.” Fundamentals of internal energy U , the enthalpy H , entropy S , free energies G , and F of a substance are presented. The chapter also presents the thermal vibration model to promote a better understanding of the U , S , and F of the crystal. It covers basic concepts of thermodynamics of magnetic transition and discusses the role and the meaning of magnetic transition in iron and steel. The chapter concludes with a general discussion on an amorphous phase from a thermodynamic viewpoint.

This chapter explains the distinction between materials and matter through the concept of microstructure. It presents the history of matter science and the establishment of metallography. The chapter provides an overview of the progress of steel technology, progress in synthetic polymers and ceramics, and establishment and development of materials science.

This chapter provides an overview of a computational method, called CALPHAD, used for the study of phase equilibria in multicomponent systems. It describes the thermodynamic models and calculation techniques employed in the software and explains how it applies to complex alloys used in industry. It also provides examples showing how CALPHAD has been used to determine the formability of metallic glass, calculate the dilation of stainless steel during phase transformation, and predict the beta transus and approach curves of commercial titanium alloys.