Grain-boundary relaxation and its effect on plasticity in nanocrystalline Fe
نویسندگان
چکیده
Grain-boundary relaxation in nanocrystalline Fe was studied by high-resolution transmission electron microscopy HREM , and its effect on plasticity was characterized by nanoindentation. Samples with grain size of 9.8 nm were synthesized by mechanical attrition and subsequently annealed at low temperatures 80 and 100 °C without affecting the grain size. While the hardness is not significantly affected by annealing, the strain-rate sensitivity peaks as a function of annealing time, suggesting two competing processes. HREM images show grain-boundary relaxation during annealing. Initially disconnected lattice planes were observed to evolve into a more continuous and ordered structure with regularly spaced grain-boundary dislocations. © 2006 American Institute of Physics. DOI: 10.1063/1.2187417
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