Fivefold twin formation during annealing of nanocrystalline Cu

E.M. BRINGA; D. FARKAS; A. CARO; Y.M. WANG; J.M. MCNANEY; R. SMITH

SCRIPTA MATERIALIA

PERGAMON-ELSEVIER SCIENCE LTD

Año: 2008 vol. 59 p. 1267 - 1270

1359-6462

Contrary to the common belief that many-fold twins in nanophase materials are due to the action of significant external stresses, we report molecular dynamics simulations of 5 nm grain size Cu samples annealed at 800 K showing the formation of fivefold twins with no external pressure. The structure of the many-fold twins is remarkably similar to those we have found to occur under uniaxial shock loading in nanocrystalline NiW. The formation mechanism of the many-fold twins is discussed.