Influence of grain boundary character on nanocrystalline plasticity
Tschopp, MA (Tschopp, M. A.); Tiwari, S (Tiwari, S.); Chosh, S (Chosh, S.); McDowell, DL (McDowell, D. L.)
PLASTICITY, FAILURE AND FATIGUE IN STRUCTURAL MATERIALS-FROM MACRO TO NANO: PROCEEDINGS OF THE HAEL MUGHRABI HONORARY SYMPOSIUM: 215-220 2008
The objective of this research is to use atomistic simulations to investigate the influence of grain boundary character on the plasticity of nanocrystalline materials. Specifically, the focus is on the grain size regime where plasticity is primarily dependent on dislocation nucleation from the grain boundaries. To demonstrate the influence of grain boundary character, an algorithm is developed that selectively increases the fraction of certain boundary misorientations - Sigma 3, Sigma 9 and Sigma 11 about the (110) misorientation axis - associated with favorable and detrimental properties, i.e., high and low nucleation stresses. Then, an embedded atom method potential for Cu is used along with a 36-grain columnar nanocrystalline grain structure to simulate the impact of grain boundary character and grain orientation distribution on uniaxial tension mechanical response.
Return to Publications page