The Deformation of Nano-whiskers of Mono-crystalline Copper: Shape Effect, Properties, Shear Banding and Necking
نویسندگان
چکیده
This paper discusses some theoretical aspects in deforming nano-whiskers of monocrystalline copper by uniaxial tension. With the aid of the molecular dynamics analysis, the present study revealed that the behaviour of a nano-whisker is very sensitive to its size, crystal orientation and geometry. The most stable surface is with (111) atomic structure and the most reliable whisker for testing is a hexagonal specimen composed of four (111) and two (100) surfaces and two (11 0) ends. The elastic modulus of a nano-whisker is very close to that of a micro-whisker but the ultimate tensile strength of the former is much higher. The mechanisms of shear banding and necking are far more complex than ever thought.
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