ATOMISTIC STUDIES OF JOGGED SCREW DISLOCATIONS IN y-TIAL ALLOYS
نویسندگان
چکیده
The behavior of jogged screw dislocations in y-TiAl alloys has been investigated with large-scale molecular dynamics (MD) simuIations. We find a new mechanism for formation of pinning points in jogged screw dislocations. We also find that the critical height for the jogs in the +[i10] directions on the (001) plane to move nonconservatively is between 3ro and 4r0, where ro is the nearest neighbor distance of aluminum atoms. Interstitials and vacancies are created during the nonconservative motions of the jogs. In addition, the formation of dislocation dipole and loops around the jogs is also observed.
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تاریخ انتشار 2008