| Theoretical model describing stress-driven migration of low-angle grain boundaries (GBs) in the vicinity of growing crack in metal matrix nanocomposites with reinforcing (metallic or ceramic) incoherent nanoinclusions is proposed. Using two-dimensional discrete dislocation dynamics approach profiles of migrating GBs are analytically calculated and critical stress for transition into unstable migration mode is found. It is shown that the presence of crack always promotes stress-driven migration and thus grain growth. |
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