Hot Nanoindentation of Nanocrystalline Ni-W Alloys
نویسندگان
چکیده
High temperature nanoindentation experiments are conducted to assess the activation enthalpy for deformation of nanocrystalline Ni-W alloys, for grain sizes between 3 and 80 nm. Thermal softening becomes less pronounced at finer grain sizes, and the activation enthalpy has an apparent inflection at a grain size near ~10-20 nm, in the vicinity the Hall-Petch breakdown. This inflection is related to that observed in the activation volume for deformation, and is associated with a shift to grain boundarymediated deformation at the finest grain sizes.
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Nanoindentation and micro-mechanical fracture toughness of electrodeposited nanocrystalline Ni–W alloy films
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