Grain-boundary dissociation by the emission of stacking faults.
نویسندگان
چکیده
A range of ^110& symmetric tilt grain boundaries ~GB’s! are investigated in several fcc metals with simulations and high-resolution electron microscopy. Boundaries with tilt angles between 50.5° and 109.5° dissociate into two boundaries 0.6 to 1.1 nm apart. The dissociation takes place by the emission of stacking faults from one boundary that are terminated by Shockley partials at a second boundary. This is a general mode of GB relaxation for low stacking fault energy metals. The reasons for the occurrence of this relaxation mode are discussed using the theory of GB dislocations.
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عنوان ژورنال:
- Physical review. B, Condensed matter
دوره 53 8 شماره
صفحات -
تاریخ انتشار 1996