Atomistic simulations of Mg-Cu metallic glasses:
mechanical properties
(1) Center for Atomic Scale Materials Physics (CAMP) and
Department of Physics, Building 307, Technical University of Denmark,
DK-2800 Lyngby, Denmark
(2) Materials Research Department, Risø National
Laboratory, DK-4000 Roskilde, Denmark
Abstract
The atomistic mechanisms of plastic deformation in amorphous metals
are far from being understood. We have derived potential parameters
for molecular dynamics simulations of Mg-Cu amorphous alloys using the
Effective Medium Theory. We have simulated the formation of alloys by
cooling from the melt, and have used these glassy configurations to
carry out simulations of plastic deformation. These involved different
compositions, temperatures (including zero), and types of deformation
(uniaxial strain/pure shear), and yielded stress-strain curves and
values of flow stress. Separate simulations were carried out to study
specific features in the stress-strain curves associated with
transitions involving internal rearrangements of atoms. Energy
barriers were calculated as a function of stress, as was the plastic
strain associated with events. The latter leads to a characteristic
volume of an event which seems to correspond with the derivative of
the barrier with respect to stress.
Materials Science and Engineering A, (in press, doi:10.1016/j.msea.2003.11.092)
Note for DTU users: We no longer have direct access to the journal
homepages, but have to go through the library service. Go to the library home page; click "Log in",
then choose "List of Journals", find Materials Science and Engineering
A, click on "Journal Homepage". Then you get the possibility to type
volume, page etc, but click instead on "Elsevier" to get to the
journal homepage, and find the paper manually under "in press". Yes,
I do have an opinion about this elegant procedure.
Last modified: 20 August 2004.
Jakob Schiøtz,
schiotz@fysik.dtu.dk
