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Combining Tight-binding and Molecular dynamics Methods to Model the Behaviour of Metals in the Plastic Regime

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 نشر من قبل Jacek Dziedzic
 تاريخ النشر 2005
  مجال البحث فيزياء
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Ultra-precision machining of metals, the breaking of nanowires under tensile stress and fracture of nanoscale materials are examples of technologically important processes which are both extremely difficult and costly to investigate experimentally. We describe a multiscale method for the simulation of such systems in which the energetically active region is modelled using a robust tight-binding scheme developed at the Naval Research Laboratory (NRL-TB) and the rest of the system is treated with molecular dynamics. We present a computer code implementing the method, geared towards non-equilibrium, cross-scaled tight-binding and molecular dynamics simulations. Apart from the presentation of the method and implementation, we discuss preliminary physical results obtained and discuss their validity.



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