Dislocations, Mesoscale Simulations and Plastic Flow

In the past twenty years, new experimental approaches, improved models and progress in simulation techniques have brought new insights into longstanding issues concerning dislocation-based plasticity in crystalline materials. During this period, three-dimensional dislocation dynamics (DD) simulations appeared and reached maturity. Their major objective is to contribute to the multiscale modelling of plastic flow by bridging the gap between atomic-scale studies of dislocation core properties and continuum models. Three-dimensional DD simulations are now becoming accessible to a wide range of users. This book presents to students and researchers in materials science and mechanical engineering a comprehensive coverage of the physical body of knowledge on which they are based and of current unsolved issues that deserve further investigation. The contents include classical studies, which are too often ignored, recent experimental and theoretical advances, and a discussion of selected applications on various topics. As the field is very broad, an extensive bibliography is provided. Chapter 1 presents an introduction to the topics discussed in the ensuing chapters. Chapters 2 and 3 are devoted to crystal plasticity, from elementary core and elastic dislocation properties to the mechanical response. The first of these discusses essentially FCC metals, and the second discusses BCC metals, some transition HCP metals and silicon. Chapter 4 presents basic elements that are common to all three-dimensional DD simulations, as well as characteristic features of each existing code, and Chapter 5 provides a synthesis of applications of DD simulations to large-scale crystals and to size effects in small-scale crystals.