1st Edition
Mechanisms of Diffusional Phase Transformations in Metals and Alloys
Developed by the late metallurgy professor and master experimentalist Hubert I. Aaronson, this collection of lecture notes details the fundamental principles of phase transformations in metals and alloys upon which steel and other metals industries are based.
Mechanisms of Diffusional Phase Transformations in Metals and Alloys is devoted to solid-solid phase transformations in which elementary atomic processes are diffusional jumps, and these processes occur in a series of so-called nucleation and growth through interface migration. Instead of relying strictly on a pedagogical approach, it documents the evolution of phase transformation concepts. The authors present topics by describing a phenomenon and then following up with a corresponding hypothesis or alternative explanation. In this way, the book also shows how the field continues to evolve and meet new challenges.
Integrated with information from a number of key papers and review articles, this volume reflects this revered and influential instructor’s unique and passionate way of introducing well-established theories and knowledge in a systematic way, at the same time introducing, in great detail, how a new idea or interpretation of a phenomenon has emerged, evolved, and gained its current status. If the published version of a theory or a model was too condensed, Aaronson worked the problem out in painstaking detail so that graduate students could follow the derivations. This collection is full of such unique "Aaronsonian idiosyncrasies," which add immense value as a powerful tool for learning in this challenging materials field.
Applied Thermodynamics
Free Energy-Composition Relationships for Binary Substitutional Solid Solutions
Free Energy-Composition Diagram and Applications to Driving Force Calculations
Thermodynamics of Interstitial Solid Solutions through Application to the Proeutectoid Ferrite Reaction in Fe-C Alloys
Diffusional Nucleation in Solid–Solid Transformations
Introduction through Qualitative General Statements
Brief Comparative Survey of Nucleation in the Four Basic Types of Phase Transformation
Outline of Approach for Development of Nucleation Theory
Proof that the Equilibrium Concentration of Critical Nuclei Is Proportional to exp(_DG*=kT)
Fictitious Equilibrium Nucleation Rate
Derivation of Steady-State Nucleation Rate
Estimation of b*
Time-Dependent Nucleation Rate
Feder et al.’s Treatment of t
Time-Dependent Nucleation Rate for Homogeneous Nucleation with Isotropic g
Ancillary Parameters
Preliminary Consideration of the Approximation for f¼DGvþW
Nonclassical Nucleation Theory
Modifications of Homogeneous Nucleation Kinetics by Anisotropic Interfacial Energy
Nucleation Kinetics at the Faces of Disordered Grain Boundaries
Comparative Nucleation Kinetics at Grain Faces, Edges, and Corners Relative to Homogeneous Nucleation: Trade-Offs between N and DG* When gab Is Isotropic Nucleation at Dislocations
Comparisons of Theory and Experiment
Diffusional Growth
Basic Differences between Diffusional Nucleation and Diffusional Growth
A General Theory of Precipitate Morphology
Disordered Interphase Boundaries
Partially and Fully Coherent Interphase Boundaries
Relative Growth Kinetics of Disordered and Partially Coherent Interphase Boundaries
Precipitation
Introduction
Metastable Equilibrium Phase Boundaries
GP Zones
Transition Phases
Nucleation Sites
Successive Reactions Involving Different Phases
Precipitate Free Zones
Coarsening (Ostwald Ripening)
Overall Evolution of the Microstructure
Massive Transformation
Definition and History
Phase Diagrams
Thermodynamics
Overall Reaction Kinetics and the Existence Range
Nucleation of Massive Transformation
Growth Kinetics
Interfacial Structure, Habit Planes, Orientation Relationships, and Growth Mechanisms
Note on the Driving Force for Trans-Interphase Boundary Diffusion during Massive Transformation in a Two-Phase Field
Cellular Reaction
Definition and Introduction
Systematics of Cellular Reactions
Nucleation of Cellular Reactions
Growth Kinetics of Cells
Pearlite Reaction
Systematics
Crystallography, Nucleation, and Growth Mechanisms
Edgewise Growth Kinetics of Pearlite
Martensitic Transformations
Definition
Salient Characteristics (Described Briefly)
Thermodynamics of Martensite Transformation
Overall Kinetics of Martensite Transformation
Nucleation of Martensite
Crystallography and Growth (or Propagation) of Martensite
Bainite Reaction and Role of Shear in Diffusional Phase Transformations
Introduction
Three Definitions of Bainite
Upper Bainite vs. Lower Bainite, and Inverse Bainite
Sources of Carbide Precipitation
References
Index
Biography
Hubert Irwin Aaronson (Hub) received his BS, MS, and Ph.D. in metallurgical engineering at Carnegie Institute of Technology, Pittsburgh, Pennsylvania (now Carnegie Mellon University). He was a worldwide leader in the field of phase transformations of metals and alloys for more than half a century. He published more than 300 technical papers, organized numerous symposia and conferences, served a number of technical committees, and was recognized with many awards. He was a member of the U.S. National Academy of Engineering, Washington, District of Columbia; a fellow of both The Minerals, Metals and Material Society and ASM International; and an honorary member of the Japan Institute of Metals, Sendai, Japan. As R.F. Mehl Professor Emeritus at Carnegie Mellon University, Hub continued his professional activities to the very end until his passing in December 2005.
Masato Enomoto received his BS and MS in physics from Tokyo University, and his Ph.D. from Carnegie Mellon University, Pittsburgh, Pennsylvania. He received many honors and awards both in the United States and in Japan for his research on phase transformations in metallic materials. He authored a book, Phase Transformations in Metals, in Japanese, and served on the editorial boards of several technical journals, including ISIJ International as editor-in-chief. He was elected a fellow of ASM International. He is currently a professor of materials science and engineering, Ibaraki University, Hitachi City, Japan.
Jong K. Lee received his BS from Seoul National University, Seoul, South Korea; his MS from the University of Washington, Seattle; and his Ph.D. from Stanford University, California. He taught at Michigan Technological University, Houghton, for over three decades. He is a fellow of ASM International, and a foreign member of both the Korean Academy of Science and Technology and the National Academy of Engineering of Korea. He continues his research activities as a professor emeritus and research professor at the Department of Materials Science and Engineering, Michigan Technological University.