Interstitial emission at grain boundary in nanolayered alpha-Fe
نویسندگان
چکیده
The Autonomous Basin Climbing method and Rate Theory are applied to investigate the interstitial emission mechanism in alpha-Fe. The atomic trajectories and potential energy landscape of the interstitial emission process induced by the S3<110>{111} symmetrical tilt grain boundary are presented. By comparing with vacancy hopping mechanism, the grain boundary influence range at finite temperature is revealed. We uncover the energetic and geometric essentials of the interstitial emission mechanism, and find connections between two previously reported defect-grain boundary interactions at long time scale. Surprisingly in nanolayered structures, higher grain boundary density raises the activation energy barriers of interstitial emission. This phenomenon is strongly correlated with the energy and local stress distribution of the grain boundary. © 2015 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.
منابع مشابه
Equal Channel Angular Pressing to Produce Ultrafine Pure Copper with Excellent Electrical and Mechanical Properties
In this article, commercially pure copper samples were severely deformed by equal channel angular pressing (ECAP) up to eight passes at room temperature. The effects of severe plastic deformation on the microstructure, mechanical properties, and electrical conductivity of the copper were investigated. The microstructure evolution was followed by optical microscope and field emission scanning el...
متن کاملThe Distribution of Grain Boundary Planes in Interstitial Free Steel
The grain boundary character distribution in a commercial IF steel has been measured as a function of lattice misorientation and boundary plane orientation. The grain boundary plane distribution revealed a relatively low anisotropy with a tendency for grain boundaries to terminate on low index planes having relatively low surface energy and large interplanar spacings. Although the most common g...
متن کاملDefect annihilation at grain boundaries in alpha-Fe
Understanding radiation responses of Fe-based metals is essential to develop radiation tolerant steels for longer and safer life cycles in harsh reactor environments. Nanograined metals have been explored as self-healing materials due to point-defect recombination at grain boundaries. The fundamental defect-boundary interactions, however, are not yet well understood. We discover that the intera...
متن کاملA modified embedded-atom method interatomic potential for the Fe–C system
A modified embedded-atom method (MEAM) interatomic potential for the Fe–C binary system has been developed using previous MEAM potentials of Fe and C. The potential parameters were determined by fitting to experimental information on the dilute heat of solution of carbon, the vacancy–carbon binding energy and its configuration, the location of interstitial carbon atoms and the migration energy ...
متن کاملHydrogen embrittlement of grain boundaries in nickel: an atomistic study
The chemomechanical degradation of metals by hydrogen is widely observed, but not clearly understood at the atomic scale. Here we report an atomistic study of hydrogen embrittlement of grain boundaries in nickel. All the possible interstitial hydrogen sites at a given grain boundary are identified by a powerful geometrical approach of division of grain boundary via polyhedral packing units of a...
متن کامل