Cooperative dissociations of misfit dislocations at bimetal interfaces
K. Liu,
R. F. Zhang,
I. J. Beyerlein,
X. Y. Chen,
H. Yang,
T. C. Germann
Affiliations
K. Liu
School of Materials Science and Engineering, and International Research Institute for Multidisciplinary Science, Beihang University, Beijing 100191, People’s Republic of China
R. F. Zhang
School of Materials Science and Engineering, and International Research Institute for Multidisciplinary Science, Beihang University, Beijing 100191, People’s Republic of China
I. J. Beyerlein
University of California at Santa Barbara, Santa Barbara, California 93106, USA
X. Y. Chen
School of Materials Science and Engineering, and International Research Institute for Multidisciplinary Science, Beihang University, Beijing 100191, People’s Republic of China
H. Yang
School of Materials Science and Engineering, and International Research Institute for Multidisciplinary Science, Beihang University, Beijing 100191, People’s Republic of China
T. C. Germann
Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
Using atomistic simulations, several semi-coherent cube-on-cube bimetal interfaces are comparatively investigated to unravel the combined effect of the character of misfit dislocations, the stacking fault energy difference between bimetal pairs, and their lattice mismatch on the dissociation of interfacial misfit dislocations. Different dissociation paths and features under loadings provide several unique deformation mechanisms that are critical for understanding interface strengthening. In particular, applied strains can cause either the formation of global interface coherency by the migration of misfit dislocations from an interface to an adjoining crystal interior or to an alternate packing of stacking faults connected by stair-rod dislocations.
