Glissile Motion of Sharp Interfaces by Interfacial Dislocation Glide

1 Glissile Motion of Sharp Interfaces by Interfacial Dislocation Glide 

Sharp boundaries of several different types can move conservatively by the glide of interfacial dislocations. In many cases, this type of motion occurs over wide ranges of temperature, including low temperatures where little thermal activation is available. 

Small-Angle Grain Boundaries. As described in Appendix B, these semicoherent boundaries are composed of arrays of discretely spaced lattice dislocations. For 

2Shuffles are small displacements of atoms (usually smaller than an atomic spacing) in a local region, such as the displacements that occur in the core of a gliding dislocation. 

Heterophase Interfaces. In certain cases, sharp heterophase interfaces are able to move in military fashion by the glissile motion of line defects possessing dislocation character. Interfaces of this type occur in martensitic displacive transformations, which are described in Chapter 24. The interface between the parent phase and the newly formed martensitic phase is a semicoherent interface that has no long-range stress field. The array of interfacial dislocations can move in glissile fashion and shuffle atoms across the interface. This advancing interface will transform 

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