摘要: Atomic level simulations are used to study crack propagation mechanisms in nanocrystalline Ni. Digital samples with a mean grain size of 5 and 8 nm containing 125 grains were used. For both sizes, the mechanism involves formation nanocracks along boundaries vicinity main crack. Crack resistance curves for two sizes indicate that smaller more ductile, requiring higher stress intensities propagation. This result is consistent softer behavior inverse Hall–Petch regime, where deformation accommodated by boundary mechanisms. The present specifically show sliding also plays an important role blunting observed these materials. In many cases, arrested as it encounters its path, showing increased Increased ductility this regime indicates there minimum function materials, located around 10- 12-nm size.
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