Mechanically-driven grain boundary relaxation in nanocrystalline metals

We recently published an article in Philosophical Magazine Letters, where we explored the ability of cyclic mechanical loading to evolve grain boundary structure and alter the mechanical behavior of nanocrystalline metals.  Molecular dynamics simulations are used to show that cyclic mechanical loading can relax the non-equilibrium grain boundary structures of nanocrystalline Ni by dissipating energy and reducing the average atomic energy of the system, leading to higher strengths. The GB processes that dominate deformation in these materials allow low-energy boundary configurations to be found through kinematically irreversible structural changes during cycling, which increases the subsequent resistance to plastic deformation.

Our article can be found at:

http://dx.doi.org/10.1080/09500839.2011.619507